463 results on '"Ultrasound (US)"'
Search Results
2. Ultrasound-Compatible Electrode for Functional Electrical Stimulation.
- Author
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Moon, Sunho, Xue, Xiangming, Ganesh, Vidisha, Shukla, Darpan, Kreager, Benjamin C., Cai, Qianqian, Wu, Huaiyu, Zhu, Yong, Sharma, Nitin, and Jiang, Xiaoning
- Subjects
ELECTRIC stimulation ,MUSCLE fatigue ,MUSCLE strength ,PATIENT monitoring ,NEUROREHABILITATION - Abstract
Functional electrical stimulation (FES) is a vital method in neurorehabilitation used to reanimate paralyzed muscles, enhance the size and strength of atrophied muscles, and reduce spasticity. FES often leads to increased muscle fatigue, necessitating careful monitoring of the patient's response. Ultrasound (US) imaging has been utilized to provide valuable insights into FES-induced fatigue by assessing changes in muscle thickness, stiffness, and strain. Current commercial FES electrodes lack sufficient US transparency, hindering the observation of muscle activity beneath the skin where the electrodes are placed. US-compatible electrodes are essential for accurate imaging and optimal FES performance, especially given the spatial constraints of conventional US probes and the need to monitor muscle areas directly beneath the electrodes. This study introduces specially designed body-conforming US-compatible FES (US-FES) electrodes constructed with a silver nanowire/polydimethylsiloxane (AgNW/PDMS) composite. We compared the performance of our body-conforming US-FES electrode with a commercial hydrogel electrode. The findings revealed that our US-FES electrode exhibited comparable conductivity and performance to the commercial one. Furthermore, US compatibility was investigated through phantom and in vivo tests, showing significant compatibility even during FES, unlike the commercial electrode. The results indicated that US-FES electrodes hold significant promise for the real-time monitoring of muscle activity during FES in clinical rehabilitative applications. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
3. Comparing the effect of FUAS and myomectomy on the elasticity of myometrium around targeted uterine fibroid
- Author
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Ziyao Wang, Yan Ma, Jia Zhou, Feng Jiang, Jin-yun Chen, and Wen-zhi Chen
- Subjects
Shear wave elastography (SWE) ,focused ultrasound ablation surgery (FUAS) ,uterine fibroid (UF) ,myomectomy (ME) ,ultrasound (US) ,Medical technology ,R855-855.5 - Abstract
Background Focused ultrasound ablation surgery (FUAS) has been widely employed to treat patients with uterine fibroid (UF). This study aimed to estimate myometrial stiffness changes in patients who received FUAS for UFs or myomectomy (ME) and compare the recovery of surrounding myometrium between FUAS and ME groups. Our results may provide more evidence for guiding the proper conception timing in patients with UF.Methods This study enrolled 173 patients from May 2022 to August 2023. Shear wave elastography (SWE) was used to dynamically monitor myometrial elasticity changes in patients before and after surgery. Moreover, our study monitored and analyzed the stiffness changes in the targeted fibroid after FUAS, as well as in the myometrium around after FUAS or ME.Results The stiffness of the myometrium around the resected fibroid was significantly higher than at the preoperative level until 6 months. Conversely, the stiffness of the surrounding myometrium was only temporarily increased 1 day after FUAS. The comparison between FUAS and ME groups regarding the stiffness of the surrounding myometrium showed that nonsignificant differences were detected between the two groups before the treatment. The stiffness of the surrounding myometrium in the ME group was statistically significantly higher than that of the FUAS group 1 day as well as 1, 3, and 6 months after the treatment, respectively.Conclusion The FUAS had less impact on the surrounding myometrium than the ME, which may be more conducive to the recovery of myometrial elasticity in patients with UF.
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- 2024
- Full Text
- View/download PDF
4. Evaluating Imaging Techniques for Diagnosing and Drainage Guidance of Psoas Muscle Abscess: A Systematic Review.
- Author
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Al-Khafaji, Murtadha Qais, Al-Smadi, Mohammad Walid, Al-Khafaji, Mustafa Qais, Aslan, Siran, Al-Khafaji, Yousif Qais, Bagossy-Blás, Panna, Al Nasser, Mohammad Hakem, Horváth, Bálint László, and Viola, Árpád
- Subjects
- *
PSOAS muscles , *MAGNETIC resonance imaging , *CONE beam computed tomography , *MEDICAL drainage , *ABSCESSES - Abstract
Background: Psoas muscle abscess (PMA) is an uncommon yet severe condition characterized by diagnostic and therapeutic challenges due to its varied etiology and nonspecific symptoms. This study aimed to evaluate the effectiveness and accuracy of various imaging techniques used in the image-guided percutaneous drainage (PD) of PMA. Methods: A systematic review was conducted following the PRISMA guidelines. We searched PubMed, Google Scholar, and Science Direct for studies published in English from 1998 onwards that reported on the use of PD in treating PMA, detailing outcomes and complications. Imaging modalities guiding PD were also examined. Results: We identified 1570 articles, selecting 39 for full review. Of these, 23 met the inclusion criteria; 19 were excluded due to unspecified PMA, absence of imaging guidance for PD, or inconclusive results. Eleven studies utilized computed tomography (CT) for PD, with six also using magnetic resonance imaging (MRI). Ten studies implemented ultrasound (US)-guided PD; variations in diagnostic imaging included combinations of US, CT, and MRI. A mixed approach using both CT and US was reported in two articles. Most studies using CT-guided PD showed complete success, while outcomes varied among those using US-guided PD. No studies employed MRI-guided PD. Conclusions: This review supports a multimodal approach for psoas abscess management, using MRI for diagnosis and CT for drainage guidance. We advocate for Cone Beam CT (CBCT)-MRI fusion techniques with navigation systems to enhance treatment precision and outcomes, particularly in complex cases with challenging abscess characteristics. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
- View/download PDF
5. An Adaptive SCG-ECG Multimodal Gating Framework for Cardiac CTA
- Author
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Ganesh, Shambavi, Abozeed, Mostafa, Aziz, Usman, Tridandapani, Srini, and Bhatti, Pamela T.
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- 2024
- Full Text
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6. Comparison of ultrasound risk stratification systems for pediatric thyroid nodules.
- Author
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Jing Yu, Yiyang Cui, Chao Fu, Xiao Ma, Caifeng Si, Yuanjing Huang, Kefei Cui, and Yan Zhang
- Subjects
THYROID nodules ,THYROID cancer ,ULTRASONIC imaging ,CHILD patients ,NEEDLE biopsy - Abstract
Background: There is currently insufficient data to validate adult-based US risk stratification systems (RSSs) for the identification of malignant thyroid nodules in a pediatric population. Methods: From October 2016 and May 2023, 173 thyroid nodules of pediatric patients (age ≤ 18 years) with definitive pathology results and ultrasound (US) examination within 1 month before surgery or fine-needle aspiration (FNA) biopsy in our institution were enrolled in this study. The clinical and US characteristics of these nodules were retrospectively reviewed and categorized according to the ACR-TIRADS, C-TIRADS, and ATA guidelines. The diagnostic performance of US-based FNA criteria (original and simulating) of the three guidelines in thyroid cancer detection was estimated. Results: The three RSSs had similar AUC according to the categories(0.849-0.852, all P > 0.05). When combined with the original FNA criteria of the three RSSs to manage the nodules, the FNA rate of ACR-TIRADS and C-TIRADS were significantly less than ATA guidelines (53.18% vs. 64.63%, P < 0.05, and 52.60% vs. 64.63%, P < 0.05). The missed malignancy rate (MMR) and unnecessary FNA rate (UFR) of ATA guidelines (50.00%, 35.85%) was highest among the three RSSs, followed by the C-TIRADS (37.80%, 19.57%) and the ACR-TIRADS (37.04%, 19.57%). When nodules < 1 cm with the highest category in each RSS biopsied, that is when using the simulating FNA thresholds, the MMR was reduced overall (all P < 0.001), without a change in the UFR (all P > 0.05). All the three RSSs showed a substantial improvement in accuracy and malignant detection rate (all P < 0.05). Conclusion: The ACR-TIRADS, C-TIRADS, and ATA guidelines showed high missed malignancy rates when using their original recommended FNA criteria. When nodules < 1 cm with the highest category in each RSS biopsied, the missed malignancy rate of each RSS was decreased. Decreasing the FNA thresholds for highly suspicious malignant nodules may therefore be an effective means of managing malignant thyroid nodules in pediatric patients. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
7. Ultrasound Image Analysis with Vision Transformers—Review.
- Author
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Vafaeezadeh, Majid, Behnam, Hamid, and Gifani, Parisa
- Subjects
- *
TRANSFORMER models , *IMAGE analysis , *ULTRASONIC imaging , *CONVOLUTIONAL neural networks , *COMPUTER vision - Abstract
Ultrasound (US) has become a widely used imaging modality in clinical practice, characterized by its rapidly evolving technology, advantages, and unique challenges, such as a low imaging quality and high variability. There is a need to develop advanced automatic US image analysis methods to enhance its diagnostic accuracy and objectivity. Vision transformers, a recent innovation in machine learning, have demonstrated significant potential in various research fields, including general image analysis and computer vision, due to their capacity to process large datasets and learn complex patterns. Their suitability for automatic US image analysis tasks, such as classification, detection, and segmentation, has been recognized. This review provides an introduction to vision transformers and discusses their applications in specific US image analysis tasks, while also addressing the open challenges and potential future trends in their application in medical US image analysis. Vision transformers have shown promise in enhancing the accuracy and efficiency of ultrasound image analysis and are expected to play an increasingly important role in the diagnosis and treatment of medical conditions using ultrasound imaging as technology progresses. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
8. Hepatic Hemangioma: Review of Imaging and Therapeutic Strategies.
- Author
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Kacała, Arkadiusz, Dorochowicz, Mateusz, Matus, Iwona, Puła, Michał, Korbecki, Adrian, Sobański, Michał, Jacków-Nowicka, Jagoda, Patrzałek, Dariusz, Janczak, Dariusz, and Guziński, Maciej
- Subjects
CAVERNOUS hemangioma ,MINIMALLY invasive procedures ,HEMANGIOMAS ,CHEMOEMBOLIZATION ,LIVER tumors ,CONTRAST-enhanced ultrasound - Abstract
Hepatic hemangiomas are the most common benign liver tumors. Typically, small- to medium-sized hemangiomas are asymptomatic and discovered incidentally through the widespread use of imaging techniques. Giant hemangiomas (>5 cm) have a higher risk of complications. A variety of imaging methods are used for diagnosis. Cavernous hemangioma is the most frequent type, but radiologists must be aware of other varieties. Conservative management is often adequate, but some cases necessitate targeted interventions. Although surgery was traditionally the main treatment, the evolution of minimally invasive procedures now often recommends transarterial chemoembolization as the treatment of choice. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
9. A High Efficiency and High Power Density Active AC/DC Converter for Battery-Less US-Powered IMDs in a 28-nm CMOS Technology
- Author
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Andrea Ballo, Alfio Dario Grasso, and Marco Privitera
- Subjects
Active rectifier ,energy harvesting ,implanted biomedical device (IMD) ,power management ,ultrasound (US) ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
In this paper, the design and experimental validation of an active rectifier for ultrasound-based implanted biomedical devices are presented. One of the main contributions is the adoption of an optimized design procedure based on the $g_{m}/I_{D}$ of the transistors. Implemented in a 28-nm CMOS technology and powered by a 0.5-mm thickness and 1-mm2 surface area piezoelectric transducer, the rectifier delivers 1-mW of power to the output load. The adoption of a square wave to drive the transmitting power transducer is experimentally demonstrated to be more power effective. The rectifier exhibits a measured peak power conversion efficiency and a power density equal to 95% and 222mW/ $mm^{2}$ , respectively, revealing itself as the best trade-off between measured power conversion efficiency and power density within the literature of US-powered AC/DC converters.
- Published
- 2024
- Full Text
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10. Antenatal ultrasound needs-analysis survey of Australian rural/remote healthcare clinicians: recommendations for improved service quality and access
- Author
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Amber Bidner, Eva Bezak, and Nayana Parange
- Subjects
Antenatal ,Obstetrics ,Ultrasound (US) ,Point-of-Care Ultrasound (PoCUS) ,Medical education/training ,Service equality ,Public aspects of medicine ,RA1-1270 - Abstract
Abstract Background Ultrasound is the primary diagnostic tool in pregnancy, capable of identifying high-risk pregnancies and life-threatening conditions, allowing for appropriate management to prevent maternal and fetal morbidity and mortality. Women and babies from rural and remote Australia and low-resource areas worldwide experience poorer health outcomes and barriers to accessing antenatal care and imaging services. Healthcare clinicians working in these regions face significant challenges practising with limited resources and accessing training opportunities. Objective To perform an exploratory needs-analysis survey investigating the availability, accessibility and use of antenatal ultrasound in rural Australia, exploring rural clinicians’ interest in and access to ultrasound training opportunities. Methods The survey tool for this cross-sectional study was designed and distributed as an anonymous online questionnaire targeting healthcare clinicians (doctors, nurses, midwives, clinic managers, Aboriginal healthcare workers) providing antenatal care in rural regions. Descriptive analysis was applied to quantitative data and thematic analysis was used to explore qualitative components. Results A total of 114 valid survey responses were analysed. Overall, 39% (43/111) reported ultrasound was not used when providing antenatal care to patients at their clinic, stating ‘Lack of ultrasound equipment (73%,29/40) and inaccessibility of training opportunities (47%,19/40) as the main reasons. For those with ultrasound (61%,68/111), estimating due date (89%,57/64) was the main use, and limited training/skills to operate the equipment (59%,38/64) and inaccessibility/distance of training opportunities (45%,29/64) were the most commonly reported barriers. Clinicians described a lack of childcare options (73%,74/102), long distances to reach ultrasound services (64%,65/102), appointment (59%,60/102) and transport availability/times (46%,47/102) as the main obstacles to patient access. Increased attendance, compliance with care directives, parental bonding and improved lifestyle choices were described by respondents as positive outcomes of antenatal ultrasound use. Conclusions Future efforts to combat inequitable service access must adopt a coordinated approach to meet the needs of pregnant women in low-resource settings. Providing portable ultrasound equipment, training in antenatal Point-of-Care ultrasound (PoCUS) with ongoing support/mentoring and accreditation of health professionals could strengthen rural workforce capacity. This, along with addressing the complex economic, environmental and socio-cultural barriers faced by patients, could improve service access and pregnancy outcomes in rural and remote communities.
- Published
- 2023
- Full Text
- View/download PDF
11. Ultrasound-Compatible Electrode for Functional Electrical Stimulation
- Author
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Sunho Moon, Xiangming Xue, Vidisha Ganesh, Darpan Shukla, Benjamin C. Kreager, Qianqian Cai, Huaiyu Wu, Yong Zhu, Nitin Sharma, and Xiaoning Jiang
- Subjects
body-conforming ultrasound-compatible electrode ,functional electrical stimulation (FES) ,silver nanowire (AgNW) electrode ,ultrasound (US) ,wearable ultrasound ,Biology (General) ,QH301-705.5 - Abstract
Functional electrical stimulation (FES) is a vital method in neurorehabilitation used to reanimate paralyzed muscles, enhance the size and strength of atrophied muscles, and reduce spasticity. FES often leads to increased muscle fatigue, necessitating careful monitoring of the patient’s response. Ultrasound (US) imaging has been utilized to provide valuable insights into FES-induced fatigue by assessing changes in muscle thickness, stiffness, and strain. Current commercial FES electrodes lack sufficient US transparency, hindering the observation of muscle activity beneath the skin where the electrodes are placed. US-compatible electrodes are essential for accurate imaging and optimal FES performance, especially given the spatial constraints of conventional US probes and the need to monitor muscle areas directly beneath the electrodes. This study introduces specially designed body-conforming US-compatible FES (US-FES) electrodes constructed with a silver nanowire/polydimethylsiloxane (AgNW/PDMS) composite. We compared the performance of our body-conforming US-FES electrode with a commercial hydrogel electrode. The findings revealed that our US-FES electrode exhibited comparable conductivity and performance to the commercial one. Furthermore, US compatibility was investigated through phantom and in vivo tests, showing significant compatibility even during FES, unlike the commercial electrode. The results indicated that US-FES electrodes hold significant promise for the real-time monitoring of muscle activity during FES in clinical rehabilitative applications.
- Published
- 2024
- Full Text
- View/download PDF
12. Comparing the effect of FUAS and myomectomy on the elasticity of myometrium around targeted uterine fibroid.
- Author
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Wang, Ziyao, Ma, Yan, Zhou, Jia, Jiang, Feng, Chen, Jin-yun, and Chen, Wen-zhi
- Subjects
- *
MYOMETRIUM , *SHEAR waves , *ELASTICITY , *ULTRASONIC imaging , *ELASTOGRAPHY , *MYOMECTOMY - Abstract
Background: Focused ultrasound ablation surgery (FUAS) has been widely employed to treat patients with uterine fibroid (UF). This study aimed to estimate myometrial stiffness changes in patients who received FUAS for UFs or myomectomy (ME) and compare the recovery of surrounding myometrium between FUAS and ME groups. Our results may provide more evidence for guiding the proper conception timing in patients with UF. Methods: This study enrolled 173 patients from May 2022 to August 2023. Shear wave elastography (SWE) was used to dynamically monitor myometrial elasticity changes in patients before and after surgery. Moreover, our study monitored and analyzed the stiffness changes in the targeted fibroid after FUAS, as well as in the myometrium around after FUAS or ME. Results: The stiffness of the myometrium around the resected fibroid was significantly higher than at the preoperative level until 6 months. Conversely, the stiffness of the surrounding myometrium was only temporarily increased 1 day after FUAS. The comparison between FUAS and ME groups regarding the stiffness of the surrounding myometrium showed that nonsignificant differences were detected between the two groups before the treatment. The stiffness of the surrounding myometrium in the ME group was statistically significantly higher than that of the FUAS group 1 day as well as 1, 3, and 6 months after the treatment, respectively. Conclusion: The FUAS had less impact on the surrounding myometrium than the ME, which may be more conducive to the recovery of myometrial elasticity in patients with UF. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
13. Multiparametric Ultrasound for Diagnosing Testicular Lesions: Everything You Need to Know in Daily Clinical Practice.
- Author
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Pozza, Carlotta, Tenuta, Marta, Sesti, Franz, Bertolotto, Michele, Huang, Dean Y., Sidhu, Paul S., Maggi, Mario, Isidori, Andrea M., and Lotti, Francesco
- Subjects
- *
DIFFERENTIAL diagnosis , *DOPPLER ultrasonography , *DIAGNOSTIC imaging , *HEALTH , *INFORMATION resources , *MEN'S health , *TESTIS tumors , *MEDICAL practice , *CONTRAST media - Abstract
Simple Summary: Testicular lesions (TLs) are challenging clinical or ultrasound findings. When large, hard palpable lumps, TL management is mainly clinical, requiring conventional color-Doppler ultrasound (CDUS) to confirm that they are solid, vascularized lesions suggesting malignancy. However, when their CDUS characteristics are uncertain or when nonpalpable, multiparametric US (mp-US) (i.e., the combination of CDUS and more recent US techniques such as contrast-enhanced US and sonoelastography) plays a key role in their characterization, aimed at differentiating benign from malignant TL. This is relevant, since TLs are frequent, testicular tumors are the most common malignancies in young men, and the accurate assessment of a TL is critical to define its correct management including testicular salvage and US follow-up or orchiectomy. In this scenario, this narrative and pictorial review reports a practical mp-US "identity card" and iconographic characterization of several benign and malignant TLs, useful to the physician in daily clinical practice. Background: Ultrasonography (US) represents the gold standard imaging method for the assessment of testicular lesions (TL). The gray-scale (GSUS) and color-Doppler (CDUS) ultrasound examination allow sonographers to investigate the size, margins, echotexture, and vascular features of TLs with the aim to differentiate benign from malignant lesions. Recently, the use of contrast-enhanced US (CEUS) and sonoelastography (SE) has led to further improvements in the differential diagnosis of TL. Although GSUS and CDUS are often sufficient to suggest the benign or malignant nature of the TL, CEUS can be decisive in the differential diagnosis of unclear findings, while SE can help to strengthen the diagnosis. The contemporary combination of GSUS, CDUS, CEUS, and SE has led to a new diagnostic paradigm named multiparametric US (mp-US), which is able to provide a more detailed characterization of TLs than single techniques alone. This narrative and pictorial review aimed to describe the mp-US appearance of several TLs. Methods: An extensive Medline search was performed to identify studies in the English language focusing on the mp-US evaluation of TLs. Results: A practical mp-US "identity card" and iconographic characterization of several benign and malignant TLs is provided herein. Conclusions: The mp-US characterization of TL reported herein can be useful in daily clinical practice. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
14. Incidental Focal Spleen Lesions: Integrated Imaging and Pattern Recognition Approach to the Differential Diagnosis.
- Author
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Corvino, Antonio, Granata, Vincenza, Tafuri, Domenico, Cocco, Giulio, and Catalano, Orlando
- Subjects
- *
DIFFERENTIAL diagnosis , *IMAGE recognition (Computer vision) , *SPLEEN , *POSITRON emission tomography , *DIAGNOSTIC imaging - Abstract
Spleen lesions and pseudolesions, detected incidentally in imaging, are not uncommon and may require further work-up. The imaging appearance of focal splenic lesions (FSLs) may not be pathognomonic, because of considerably overlapping features. Consequently, all imaging techniques lack specificity to fully characterize FSLs. Clinical correlation is mandatory, so as, first of all, to categorize the patient as having or not having a history of solid or hematologic malignancy. Nowadays, many patients have old imaging studies available for comparison and, consequently, it is important to understand if the lesion was previously present or not, and if the size is the same or has changed. In the absence of comparison studies, and with a lack of imaging features of benignity, further investigation may be necessary, using PET, biopsy, or short-term follow-up. Some algorithms have been proposed to manage incidental FSLs; however, none of these strategies has been validated by prospective studies to date. In this review we illustrate the topic of incidental FSLs and we analyze a number of published algorithms. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
15. Evaluation of antenatal point-of-care ultrasound training workshops for rural/remote healthcare clinicians: a prospective single cohort study
- Author
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Amber Bidner, Eva Bezak, and Nayana Parange
- Subjects
Medical education/training ,Obstetrics and gynaecology ,Ultrasound (US) ,Sonography ,Point-of-care- ultrasound (PoCUS) ,Antenatal ,Special aspects of education ,LC8-6691 ,Medicine - Abstract
Abstract Background There is limited access to life-saving antenatal ultrasound in low-resource rural and remote settings worldwide, including Australia, mainly due to shortages in skilled staff. Point-of-care ultrasound (PoCUS) offers a viable solution to this service deficit, however, rural clinicians face many barriers accessing training and professional development critical to advancing their clinical practice. Standards for PoCUS training and competency assessment are unclear. Regulation is lacking globally, allowing untrained and inexperienced clinicians to practice PoCUS clinically. Methods This prospective single cohort study aimed to evaluate antenatal PoCUS training workshops for General Practitioners (GPs) and Midwives/Nurses (M/Ns) from rural/remote Australia, assessing the impact of the training on trainees’ knowledge, confidence and translation of PoCUS into clinical practice. Two-day antenatal ultrasound workshops were delivered at the University of South Australia (UniSA) in 2018 and 2019 to 41 rural/remote clinicians . The training was designed and evaluated using the New world Kirkpatrick Evaluation Framework. Sixteen GPs and 25 M/Ns with mixed prior ultrasound experience were funded to attend. The course consisted of lectures interspaced with hands-on training sessions using high-fidelity simulators and live pregnant models. Pre- and post-knowledge assessments were performed. Post-workshop evaluation and follow-up surveys (3- and 6-month post-training) assessed the workshops and changes to trainees’ clinical practice. A 2-day follow-up training session was conducted 12 months after the workshops for 9 trainees. Results Pre/post knowledge testing demonstrated a 22% mean score improvement (95% CI 17.1 to 27.8, P
- Published
- 2022
- Full Text
- View/download PDF
16. Ultrasound Image Analysis with Vision Transformers—Review
- Author
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Majid Vafaeezadeh, Hamid Behnam, and Parisa Gifani
- Subjects
transformer ,ultrasound (US) ,deep learning ,convolutional neural network (CNN) ,vision transformer (ViT) ,swin transformer ,Medicine (General) ,R5-920 - Abstract
Ultrasound (US) has become a widely used imaging modality in clinical practice, characterized by its rapidly evolving technology, advantages, and unique challenges, such as a low imaging quality and high variability. There is a need to develop advanced automatic US image analysis methods to enhance its diagnostic accuracy and objectivity. Vision transformers, a recent innovation in machine learning, have demonstrated significant potential in various research fields, including general image analysis and computer vision, due to their capacity to process large datasets and learn complex patterns. Their suitability for automatic US image analysis tasks, such as classification, detection, and segmentation, has been recognized. This review provides an introduction to vision transformers and discusses their applications in specific US image analysis tasks, while also addressing the open challenges and potential future trends in their application in medical US image analysis. Vision transformers have shown promise in enhancing the accuracy and efficiency of ultrasound image analysis and are expected to play an increasingly important role in the diagnosis and treatment of medical conditions using ultrasound imaging as technology progresses.
- Published
- 2024
- Full Text
- View/download PDF
17. Hepatic Hemangioma: Review of Imaging and Therapeutic Strategies
- Author
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Arkadiusz Kacała, Mateusz Dorochowicz, Iwona Matus, Michał Puła, Adrian Korbecki, Michał Sobański, Jagoda Jacków-Nowicka, Dariusz Patrzałek, Dariusz Janczak, and Maciej Guziński
- Subjects
hepatic hemangiomas ,atypical hepatic hemangioma ,computed tomography (CT) ,magnetic resonance (MR) ,ultrasound (US) ,contrast-enhanced ultrasound (CEUS) ,Medicine (General) ,R5-920 - Abstract
Hepatic hemangiomas are the most common benign liver tumors. Typically, small- to medium-sized hemangiomas are asymptomatic and discovered incidentally through the widespread use of imaging techniques. Giant hemangiomas (>5 cm) have a higher risk of complications. A variety of imaging methods are used for diagnosis. Cavernous hemangioma is the most frequent type, but radiologists must be aware of other varieties. Conservative management is often adequate, but some cases necessitate targeted interventions. Although surgery was traditionally the main treatment, the evolution of minimally invasive procedures now often recommends transarterial chemoembolization as the treatment of choice.
- Published
- 2024
- Full Text
- View/download PDF
18. Biomimetic nanobubbles for triple-negative breast cancer targeted ultrasound molecular imaging
- Author
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Natacha Jugniot, Tarik F. Massoud, Jeremy J. Dahl, and Ramasamy Paulmurugan
- Subjects
Triple negative breast cancer ,Nanobubble ,Molecular imaging ,Cancer early detection ,Cancer cell membrane ,Ultrasound (US) ,Biotechnology ,TP248.13-248.65 ,Medical technology ,R855-855.5 - Abstract
Abstract Triple-negative breast cancer (TNBC) is a highly heterogeneous breast cancer subtype with poor prognosis. Although anatomical imaging figures prominently for breast lesion screening, TNBC is often misdiagnosed, thus hindering early medical care. Ultrasound (US) molecular imaging using nanobubbles (NBs) capable of targeting tumor cells holds great promise for improved diagnosis and therapy. However, the lack of conventional biomarkers in TNBC impairs the development of current targeted agents. Here, we exploited the homotypic recognition of cancer cells to synthesize the first NBs based on TNBC cancer cell membrane (i.e., NBCCM) as a targeted diagnostic agent. We developed a microfluidic technology to synthesize NBCCM based on the self-assembly property of cell membranes in aqueous solutions. In vitro, optimal NBCCM had a hydrodynamic diameter of 683 ± 162 nm, showed long-lasting US contrast enhancements and homotypic affinity. In vivo, we demonstrated that NBCCM showed increased extravasation and retention in a TNBC mouse model compared to non-targeted NBs by US molecular imaging. Peak intensities and areas under the curves from time-intensity plots showed a significantly enhanced signal from NBCCM compared to non-targeted NBs (2.1-fold, P = 0.004, and, 3.6-fold, P = 0.0009, respectively). Immunofluorescence analysis further validated the presence of NBCCM in the tumor microenvironment. Circumventing the challenge for universal cancer biomarker identification, our approach could enable TNBC targeting regardless of tumor tissue heterogeneity, thus improving diagnosis and potentially gene/drug targeted delivery. Ultimately, our approach could be used to image many cancer types using biomimetic NBs prepared from their respective cancer cell membranes.
- Published
- 2022
- Full Text
- View/download PDF
19. The diagnostic performance of magnetic resonance imaging (MRI) in the evaluation of breast ultrasound non-mass lesions: A systematic review.
- Author
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Ahmadinejad, Nasrin, Golezar, Mohammad Hossein, Rouzbahani, Maedeh, Hassanzadeh, Sara, and Rastkar, Mohsen
- Subjects
- *
MAGNETIC resonance imaging , *BREAST ultrasound , *LITERATURE reviews , *DUCTAL carcinoma - Abstract
Aim: This study aims to conduct a systematic review of the current knowledge regarding the diagnostic performance of MRI in the investigation of non-mass lesions of the breast. Method: Up to July 2022, PubMed, Scopus, Web of Science, and Embase were searched comprehensively. All studies examining the diagnostic performance of MRI in non-mass lesions were included except review articles, articles published in a language other than English, and case reports or series of cases. Two independent reviewers performed a literature review and data extraction. A checklist for cross-sectional studies developed by the Joanna Briggs Institute (JBI) was used to assess sources of bias. Results: The systematic review included two studies. If any enhancement is present on MRI, most ultrasound NMLs exhibit a non-mass-enhancement. We found that the distribution of non-mass enhancement lesions was primarily segmental and regional. The highest number of malignancies is associated with segmental distributions since 81.8% of the cases with segmental enhancement were ductal carcinomas, specifically DCIS. Conclusion: Non-mass lesions of the US that do not enhance in MRI have a good prognosis. Breast cancer is very unlikely in these cases, so follow-up is acceptable unless there is a suspicion of malignancy on mammography. In cases where regional and segmental enhancement of NMLs occurs on CE-MRI, ductal carcinomas may be present, and a pathological examination is warranted. [ABSTRACT FROM AUTHOR]
- Published
- 2023
20. Evaluation of antenatal point-of-care ultrasound training workshops for rural/remote healthcare clinicians: a prospective single cohort study.
- Author
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Bidner, Amber, Bezak, Eva, and Parange, Nayana
- Subjects
RURAL nursing ,ADULT education workshops ,ULTRASONIC imaging ,MEDICAL personnel ,COHORT analysis ,POINT-of-care testing - Abstract
Background: There is limited access to life-saving antenatal ultrasound in low-resource rural and remote settings worldwide, including Australia, mainly due to shortages in skilled staff. Point-of-care ultrasound (PoCUS) offers a viable solution to this service deficit, however, rural clinicians face many barriers accessing training and professional development critical to advancing their clinical practice. Standards for PoCUS training and competency assessment are unclear. Regulation is lacking globally, allowing untrained and inexperienced clinicians to practice PoCUS clinically. Methods: This prospective single cohort study aimed to evaluate antenatal PoCUS training workshops for General Practitioners (GPs) and Midwives/Nurses (M/Ns) from rural/remote Australia, assessing the impact of the training on trainees' knowledge, confidence and translation of PoCUS into clinical practice. Two-day antenatal ultrasound workshops were delivered at the University of South Australia (UniSA) in 2018 and 2019 to 41 rural/remote clinicians. The training was designed and evaluated using the New world Kirkpatrick Evaluation Framework. Sixteen GPs and 25 M/Ns with mixed prior ultrasound experience were funded to attend. The course consisted of lectures interspaced with hands-on training sessions using high-fidelity simulators and live pregnant models. Pre- and post-knowledge assessments were performed. Post-workshop evaluation and follow-up surveys (3- and 6-month post-training) assessed the workshops and changes to trainees' clinical practice. A 2-day follow-up training session was conducted 12 months after the workshops for 9 trainees. Results: Pre/post knowledge testing demonstrated a 22% mean score improvement (95% CI 17.1 to 27.8, P < 0.0001). At 6 months, 62% of trainees were performing PoCUS that had assisted in patient management and clinical diagnosis, and 46% reported earlier diagnosis and changes to patient management. 74% of trainees had increased scanning frequency and 93% reported improved scanning confidence. Conclusion: This study demonstrated intensive 2-day workshops can equip clinicians with valuable antenatal PoCUS skills, offering a viable solution to assist in the assessment and management of pregnant women in the rural/resource-poor setting where access to ultrasound services is limited or non-existent. Geographical isolation and lack of onsite specialist supervision poses an ongoing challenge to the continuing professional development of remote trainees and the implementation of PoCUS. [ABSTRACT FROM AUTHOR]
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- 2022
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21. Energy, Waves, and Forces in Bilateral Fracture of the Femoral Necks: Two Case Presentations and Updated Critical Review.
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Baciu, Cosmin Constantin
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FEMORAL neck fractures , *HIP fractures , *STRESS waves , *SHOCK waves , *FEMUR neck , *TYPE 1 diabetes - Abstract
Two case reports and an updated critical review on bilateral fractures of the femoral neck are presented. Bilateral fractures of the femoral neck have been investigated for at least 80 years and are treated as rare cases. The primary cause is usually considered an external shock; however, aside from high energy shocks (e.g., falling and impact with hard, rigid surfaces, traffic accidents, etc.) the underlying causes of femoral neck frailty have not yet been fully understood. Although not exhaustive, the review spans cases reported as early as 1944 and compares their conclusions in line with medicine developments at the time of the reports until present. The discussion is perhaps controversial at times; it brings to the fore the energy balance between shock waves and stress waves. The two cases reported here add to the review, one highlighting the biomechanics, and the other supporting more recent findings on metabolic disorders, which ultimately lead to enhanced frailty of the femoral neck. Investigation of the fractures has been performed with X-ray radiographs, MRI, and CT, with a follow up using a Doppler US to check blood flow in the lower zone of the limbs. The second case was investigated both for fractures and metabolic diseases, e.g., type I diabetes and kidney failure (dialysis). In Case 1 the second fracture was not observable at the time of admission, and therefore two surgery operations were performed at seven days interval. Taperloc Complete prostheses (Zimmer Biomet) were applied. Case 2 suffered a second fracture in the right hip in the segment above the knee and required better fixation with cables. Despite this, she returned one month later with a new crack in the femur. Case 1 is a typical case of wear consequences on the biomechanics of the hill pad-tibia-femur-femoral neck system, where tension of the neck occurred due to a stress wave rather than a shock wave. This can be proven by the absence of a second fracture from the images first acquired, the only evidence being pain and walking difficulty. Case 2 shows that metabolic diseases can dramatically enhance the frequency of bilateral femoral neck fractures. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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22. Model based on ultrasound and clinicopathological characteristics for early prediction of pathological complete response to neoadjuvant chemotherapy in breast cancer.
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Wen X, Chen J, Zhong J, Zhuang Y, Deng B, Lin Y, and Su Z
- Abstract
Background: Accurate assessment of pathological complete response (pCR) to neoadjuvant chemotherapy (NAC) in breast cancer (BC) is crucial for mitigating chemotherapy-related toxicity in patients who do not respond to the treatment. Conventional ultrasound (US) has become a pivotal method for evaluating treatment response due to its cost-effectiveness, convenience, and absence of ionizing radiation. The objective of this study was to develop a model combining US and clinicopathological characteristics at baseline, as well as US features after one cycle of NAC, to predict the pCR to NAC in BC., Methods: This retrospective study included 74 patients with invasive BC who underwent NAC from January 2022 to December 2023. Data from US and clinicopathological characteristics before NAC (pre-NAC) and US features after one cycle of NAC were collected from all patients. Univariate and multivariate analyses were used to screen the factors independently associated with pCR and to develop the prediction model. Receiver operating characteristic (ROC) curve analysis was performed, and the area under the curve (AUC), sensitivity, and specificity were calculated to assess the predictive efficiency., Results: Four characteristics, including human epidermal growth factor receptor 2 (HER2)-positive [odds ratio (OR) 9.265; 95% confidence interval (CI): 1.617-53.095, P=0.012] and absence of posterior feature or posterior acoustic enhancement of the breast mass on the US pre-NAC (OR 9.435; 95% CI: 1.585-56.180, P=0.014), the maximum diameter reduction measured with the US (OR 1.081; 95% CI: 1.009-1.157, P=0.026), and the angular or spiculated margin of the breast lesion with the US after one cycle of NAC (OR 9.475; 95% CI: 1.247-71.969, P=0.030), were screened as independent predictors. The AUC, sensitivity, and specificity of the prediction model were 0.912, 90.0%, and 79.6%, respectively., Conclusions: US and clinicopathological characteristics at baseline and the US features after one cycle of NAC helped predict pCR for BC. The prediction model may enable early evaluation of the efficacy of treatment strategies and guide less invasive surgical options or personalized post-treatment plans., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-24-1268/coif). The authors have no conflicts of interest to declare., (2024 AME Publishing Company. All rights reserved.)
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- 2024
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23. Ultrasound (US) of the fingers: anatomy and pathology.
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Quílez Caballero E, Bueno Horcajadas ÁL, Cebada Chaparro E, De Iruarrizaga Gana M, López-Vidaur Franco I, and Martel Villagrán J
- Abstract
The development and evolution of high-frequency probes in current ultrasound systems have enabled us to obtain more detailed information about small and superficial structures, such as the fingers, which are frequently injured in a significant portion of the population (traumatic injuries account for 28% of musculoskeletal system injuries) and can result in substantial disability for affected patients. Due to its superior accessibility, resolution, and ability to perform dynamic studies, ultrasound has become the imaging technique of choice for evaluating these conditions. It covers a range of pathologies, including tendinous, ligamentous, and articular injuries, as well as soft tissue tumors and pseudotumors, which will be described in detail in the main body of the article. However, given the complexity and small size of these structures, along with the necessity for early diagnosis to enable surgical treatment and minimize functional impairment, it is essential to be well-versed in the anatomy, examination techniques, and basic pathologies of the fingers to perform a thorough evaluation and achieve an accurate diagnosis. Therefore, the primary objective of this article is to present this content in a practical and straightforward manner, making it useful not only for radiology professionals but also for other specialists, since ultrasound is the most commonly used imaging method outside of radiology., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-24-591/coif). The special issue “Advances in Diagnostic Musculoskeletal Imaging and Image-guided Therapy” was commissioned by the editorial office without any funding or sponsorship. J.M.V. served as the unpaid Guest Editor of the issue. The authors have no other conflicts of interest to declare., (2024 AME Publishing Company. All rights reserved.)
- Published
- 2024
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24. Myosteatosis: diagnostic significance and assessment by imaging approaches.
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Garcia-Diez AI, Porta-Vilaro M, Isern-Kebschull J, Naude N, Guggenberger R, Brugnara L, Milinkovic A, Bartolome-Solanas A, Soler-Perromat JC, Del Amo M, Novials A, and Tomas X
- Abstract
Myosteatosis has emerged as an important concept in muscle health as it is associated with an increased risk of adverse health outcomes, a higher rate of complications, and increased mortality associated with ageing, chronic systemic and neuromuscular diseases, cancer, metabolic syndromes, degenerative events, and trauma. Myosteatosis involves ectopic infiltration of fat into skeletal muscle, and it exhibits a negative correlation with muscle mass, strength, and mobility representing a contributing factor to decreased muscle quality. While myosteatosis serves as an additional biomarker for sarcopenia, cachexia, and metabolic syndromes, it is not synonymous with sarcopenia. Myosteatosis induces proinflammatory changes that contribute to decreased muscle function, compromise mitochondrial function, and increase inflammatory response in muscles. Imaging techniques such as computed tomography (CT), particularly opportunistic abdominal CT scans, and magnetic resonance imaging (MRI) or magnetic resonance spectroscopy (MRS), have been used in both clinical practice and research. And in recent years, ultrasound has emerged as a promising bedside tool for measuring changes in muscle tissue. Various techniques, including CT-based muscle attenuation (MA) and intermuscular adipose tissue (IMAT) quantification, MRI-based proton density fat fraction (PDFF) and T1-T2 mapping, and musculoskeletal ultrasound (MSUS)-based echo intensity (EI) and shear wave elastography (SWE), are accessible in clinical practice and can be used as adjunct biomarkers of myosteatosis to assess various debilitating muscle health conditions. However, a stan¬dard definition of myosteatosis with a thorough understanding of the pathophysiological mechanisms, and a consensus in assessment methods and clinical outcomes has not yet been established. Recent developments in image acquisition and quantification have attempted to develop an appropriate muscle quality index for the assessment of myosteatosis. Additionally, emerging studies on artificial intelligence (AI) may provide further insights into quantification and automated assessment, including MRS analysis. In this review, we discuss the pathophysiological aspects of myosteatosis, all the current imaging techniques and recent advances in imaging assessment as potential biomarkers of myosteatosis, and the most common clinical conditions involved., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-24-365/coif). The special issue “Advances in Diagnostic Musculoskeletal Imaging and Image-guided Therapy” was commissioned by the editorial office without any funding or sponsorship. X.T. served as the unpaid Guest Editor of the issue. The authors have no other conflicts of interest to declare., (2024 AME Publishing Company. All rights reserved.)
- Published
- 2024
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25. Magnetic resonance classification proposal for medial gastrocnemius muscle injuries.
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Isern-Kebschull J, Pedret C, García-Diez AI, Del Amo M, Balius R, Alomar X, Soler-Perromat JC, Bartolomé-Solanas A, Porta-Vilaró M, Tomas X, and Rodas G
- Abstract
Calf muscle injuries are common among athletes and occupational populations, with highly variable recovery times that are challenging to be predicted at the initial clinical evaluation. Specifically, in distal gastrocnemius muscle injuries, an ultrasound-based severity classification has shown to be useful for estimating the recovery time. According to the location of lesions and the recognition of some US signs, four types of injuries of the distal gastrocnemius muscle were described. Since magnetic resonance imaging (MRI) has proven to be useful in diagnosing and prognosticating muscle injuries by assessing the extent of affected connective tissue, a specific MRI protocol involving T1-weighted and fluid-sensitive static and dynamic acquisitions has been developed aimed to characterize the four types of injuries. We here describe the characteristics of this new MRI protocol and the interpretation of images, which will be useful to improve the recognition of acute and delayed distal gastrocnemius muscle injuries. The proposed classification includes: myoaponeurotic muscle injury without aponeurotic discontinuities (type 1), myoaponeurotic muscle injury with aponeurotic discontinuities (type 2), isolated free aponeurosis discontinuity (type 3), and a mixed myoaponeurotic-aponeurotic injury pattern (type 4). A comprehensive understanding of the MRI features associated with each injury type, in conjunction with multidisciplinary team collaboration, is essential for optimizing the athlete's recovery and return to play., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-24-298/coif). The special issue “Advances in Diagnostic Musculoskeletal Imaging and Image-guided Therapy” was commissioned by the editorial office without any funding or sponsorship. X.T. served as the unpaid Guest Editor of the issue. The authors have no other conflicts of interest to declare., (2024 AME Publishing Company. All rights reserved.)
- Published
- 2024
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26. Non-palpable contraceptive implants localization: review of imaging techniques and algorithm proposal.
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Soler-Perromat JC, Bartolomé-Solanas Á, Del Amo M, Isern-Kebschull J, Porta-Vilaró M, García-Diez AI, de Guirior C, and Tomás X
- Abstract
Contraceptive arm implants provide long-acting contraception through a subdermal rod. The device is intended to be placed on the medial side of the non-dominant upper arm. There are two main types of implants: etonogestrel (ENG)-releasing devices, such as Implanon NXT
® /Nexplanon® , and levonorgestrel (LNG)-releasing devices, including Sino-implant II® and Jadelle® . Since the rods are not biodegradable, the implants must be removed after the device's licensed duration. When the implant is palpable and located in subcutaneous tissue, it can be removed with a small skin incision, without the need for imaging. If the implant is not palpable, imaging techniques must be used for precise localization. Ultrasound (US) is the first-line imaging modality for non-palpable implants, allowing quick and accurate localization in the vast majority of cases. The patient can usually indicate the implant insertion site, which speeds up the localization process. If the implant cannot be located using US, other imaging techniques should be used. X-ray can also be useful for a quick localization assessment of radiopaque implants. Magnetic resonance imaging (MRI) is valuable for locating deep or migrated implants, especially if the device has not been locatable through US or X-ray. In case of suspected pulmonary migration, a thoracic computed tomography (CT) should be performed for arterial implant detection. In this article, we review the imaging techniques used for implant localization. We also present an algorithm that recommends a sequential approach to implant localization, integrating imaging modalities based on implant characteristics and patient presentation., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-24-353/coif). The special issue “Advances in Diagnostic Musculoskeletal Imaging and Image-guided Therapy” was commissioned by the editorial office without any funding or sponsorship. X.T. served as the unpaid Guest Editor of the issue. The authors have no other conflicts of interest to declare., (2024 AME Publishing Company. All rights reserved.)- Published
- 2024
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27. Immunotheranostic microbubbles (iMBs) - a modular platform for dendritic cell vaccine delivery applied to breast cancer immunotherapy.
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Jugniot, Natacha, Dahl, Jeremy J., and Paulmurugan, Ramasamy
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- *
DENDRITIC cells , *TRIPLE-negative breast cancer , *MICROBUBBLES , *DECOMPRESSION sickness , *BREAST cancer , *CONTRAST-enhanced ultrasound , *CANCER cell growth - Abstract
Background: Therapeutic strategies engaging the immune system against malignant cells have revolutionized the field of oncology. Proficiency of dendritic cells (DCs) for antigen presentation and immune response has spurred interest on DC-based vaccines for anti-cancer therapy. However, despite favorable safety profiles in patients, current DC-vaccines have not yet presented significant outcome due to technical barriers in active DC delivery, tumor progression, and immune dysfunction. To maximize the therapeutic response, we present here a unique cell-free DC-based vaccine capable of lymphoid organ targeting and eliciting T-cell-mediated anti-tumor effect. Methods: We developed this novel immunotheranostic platform using plasma membranes derived from activated DCs incorporated into ultrasound contrast microbubbles (MBs), thereby offering real-time visualization of MBs' trafficking and homing in vivo. Human PBMC-derived DCs were cultured ex vivo for controlled maturation and activation using cell membrane antigens from breast cancer cells. Following DC membrane isolation, immunotheranostic microbubbles, called DC-iMBs, were formed for triple negative breast cancer treatment in a mouse model harboring a human reconstituted immune system. Results: Our results demonstrated that DC-iMBs can accumulate in lymphoid organs and induce anti-tumor immune response, which significantly reduced tumor growth via apoptosis while increasing survival length of the treated animals. The phenotypic changes in immune cell populations upon DC-iMBs delivery further confirmed the T-cell-mediated anti-tumor effect. Conclusion: These early findings strongly support the potential of DC-iMBs as a novel immunotherapeutic cell-free vaccine for anti-cancer therapy. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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28. Sparse 2-D PZT-on-PCB Arrays With Density Tapering.
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Wei, Luxi, Boni, Enrico, Ramalli, Alessandro, Fool, Fabian, Noothout, Emile, van der Steen, Antonius F. W., Verweij, Martin D., Tortoli, Piero, De Jong, Nico, and Vos, Hendrik J.
- Subjects
- *
PIEZOELECTRIC ceramics , *RAPID prototyping , *PRINTED circuits - Abstract
Two-dimensional (2-D) arrays offer volumetric imaging capabilities without the need for probe translation or rotation. A sparse array with elements seeded in a tapering spiral pattern enables one-to-one connection to an ultrasound machine, thus allowing flexible transmission and reception strategies. To test the concept of sparse spiral array imaging, we have designed, realized, and characterized two prototype probes designed at 2.5-MHz low-frequency (LF) and 5-MHz high-frequency (HF) center frequencies. Both probes share the same electronic design, based on piezoelectric ceramics and rapid prototyping with printed circuit board substrates to wire the elements to external connectors. Different center frequencies were achieved by adjusting the piezoelectric layer thickness. The LF and HF prototype probes had 88% and 95% of working elements, producing peak pressures of 21 and 96 kPa/V when focused at 5 and 3 cm, respectively. The one-way −3-dB bandwidths were 26% and 32%. These results, together with experimental tests on tissue-mimicking phantoms, show that the probes are viable for volumetric imaging. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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29. Phased Array Beamforming Methods for Powering Biomedical Ultrasonic Implants.
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Benedict, Braeden C., Ghanbari, Mohammad Meraj, and Muller, Rikky
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MEDICAL ultrasonics , *BEAMFORMING , *NEURAL stimulation , *TIME reversal , *SOUND wave scattering , *PHASED array antennas , *TRANSDUCERS - Abstract
Millimeter-scale implants using ultrasound (US) for power and communication have been proposed for a range of deep-tissue applications, including neural recording and stimulation. However, published implementations have shown high sensitivity to misalignment with the external US transducer. Ultrasonic beamforming using a phased array to these implants can improve tolerance to misalignment, reduce implant volume, and allow multiple implants to be operated simultaneously in different locations. This article details the design of a custom planar phased array US system, which is capable of steering and focusing US power within a 3-D volume. Analysis and simulation is performed to determine the choice of array element pitch, with special attention given to maximizing the power available at the implant while meeting FDA limits for diagnostic US. Time reversal (TR) is proposed as a computationally simple approach to beamforming that is robust despite scattering and inhomogeneity of the acoustic medium. This technique is demonstrated both in active drive and pulse-echo modes, and it is experimentally compared with other beamforming techniques by measuring energy transfer efficiency. Simultaneous power delivery to multiple implants is also demonstrated. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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30. Encapsulation of Nutraceuticals in Yoghurt and Beverage Products Using the Ultrasound and High-Pressure Processing Technologies.
- Author
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Silva, Mayumi, Kadam, Mayur Raghunath, Munasinghe, Dilusha, Shanmugam, Akalya, and Chandrapala, Jayani
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YOGURT ,FUNCTIONAL foods ,ULTRASONIC imaging ,DAIRY products ,NUTRITIONAL value ,PRODUCT improvement - Abstract
Dairy and beverage products are considered highly nutritious. The increase demand for added nutritional benefits within the food systems consumed by the consumers paves the pathway towards fortifying nutraceuticals into these products. However, nutraceuticals are highly unstable towards harsh processing conditions. In addition, the safety of dairy and beverage products plays a very important role. Therefore, various heat treatments are in practice. As the heat-treated dairy and beverage products tends to illustrate several alterations in their organoleptic characteristics and nutritional properties, the demand for alternative non-thermal processing technologies has increased extensively within the food industry. Ultrasound and high-pressure processing technologies are desirable for this purpose as well as a safe and non-destructive technology towards encapsulation of nutraceuticals into food systems. There are benefits in implementing these two technologies in the production of dairy and beverage products with encapsulants, such as manufacturing high-quality products with improved nutritional value while simultaneously enhancing the sensory characteristics such as flavour, taste, texture, and colour and attaining the microbial quality. The primary objective of this review is to provide detailed information on the encapsulation of nutraceuticals and mechanisms involved with using US and HPP technologies on producing encapsulated yoghurt and beverage products. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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31. Current Imaging Diagnosis of Hepatocellular Carcinoma.
- Author
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Chartampilas, Evangelos, Rafailidis, Vasileios, Georgopoulou, Vivian, Kalarakis, Georgios, Hatzidakis, Adam, and Prassopoulos, Panos
- Subjects
- *
ULTRASONIC imaging , *CONTRAST media , *MAGNETIC resonance imaging , *DIAGNOSTIC imaging , *COMPUTED tomography , *PERFUSION imaging , *SENSITIVITY & specificity (Statistics) , *HEPATOCELLULAR carcinoma , *PERFUSION - Abstract
Simple Summary: The role of imaging in the management of hepatocellular carcinoma (HCC) has significantly evolved and expanded beyond the plain radiological confirmation of the tumor based on the typical appearance in a multiphase contrast-enhanced CT or MRI examination. The introduction of hepatobiliary contrast agents has enabled the diagnosis of hepatocarcinogenesis at earlier stages, while the application of ultrasound contrast agents has drastically upgraded the role of ultrasound in the diagnostic algorithms. Newer quantitative techniques assessing blood perfusion on CT and MRI not only allow earlier diagnosis and confident differentiation from other lesions, but they also provide biomarkers for the evaluation of treatment response. As distinct HCC subtypes are identified, their correlation with specific imaging features holds great promise for estimating tumor aggressiveness and prognosis. This review presents the current role of imaging and underlines its critical role in the successful management of patients with HCC. Hepatocellular carcinoma (HCC) is the fourth leading cause of cancer related death worldwide. Radiology has traditionally played a central role in HCC management, ranging from screening of high-risk patients to non-invasive diagnosis, as well as the evaluation of treatment response and post-treatment follow-up. From liver ultrasonography with or without contrast to dynamic multiple phased CT and dynamic MRI with diffusion protocols, great progress has been achieved in the last decade. Throughout the last few years, pathological, biological, genetic, and immune-chemical analyses have revealed several tumoral subtypes with diverse biological behavior, highlighting the need for the re-evaluation of established radiological methods. Considering these changes, novel methods that provide functional and quantitative parameters in addition to morphological information are increasingly incorporated into modern diagnostic protocols for HCC. In this way, differential diagnosis became even more challenging throughout the last few years. Use of liver specific contrast agents, as well as CT/MRI perfusion techniques, seem to not only allow earlier detection and more accurate characterization of HCC lesions, but also make it possible to predict response to treatment and survival. Nevertheless, several limitations and technical considerations still exist. This review will describe and discuss all these imaging modalities and their advances in the imaging of HCC lesions in cirrhotic and non-cirrhotic livers. Sensitivity and specificity rates, method limitations, and technical considerations will be discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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32. Leydig Cell Tumors of the Testis: An Update of the Imaging Characteristics of a Not So Rare Lesion.
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Maxwell, Florian, Savignac, Alexia, Bekdache, Omar, Calvez, Sandra, Lebacle, Cédric, Arama, Emmanuel, Garrouche, Nada, and Rocher, Laurence
- Subjects
- *
GENITALIA tumors , *MAGNETIC resonance imaging , *DIAGNOSTIC imaging , *TESTIS tumors , *DOPPLER ultrasonography , *KLINEFELTER'S syndrome - Abstract
Simple Summary: Stromal tumors of the testis are rare. However, among this group, Leydig cell tumors (LCT) are the most frequent, and recent studies suggest that LCTs account for up to 22% of small testicular nodules. It is now accepted that small LCTs can benefit from testis-sparing surgery or in some selected cases radiological surveillance. Since percutaneous testicular biopsy is still not recommended, the diagnosis of LCT rests on multimodal imaging techniques. Therefore, it is essential for the radiologist and the urologist to know the main imaging features of LCTs in ultrasound and MRI. Pre-operative testicular tumor characterization is a challenge for radiologists and urologists. New data concerning imaging approaches or immunochemistry markers improve the management of patients presenting with a testicular tumor, sometimes avoiding radical orchiectomy. In the past 20 years, imaging modalities, especially ultrasound (US) and magnetic resonance imaging (MRI), improved, allowing for great progress in lesion characterization. Leydig cell tumors (LCT) are rare testicular tumors developing from the stromal tissue, with relatively scarce literature, as most of the studies focus on the much more frequent germ cell tumors. However, with the increase in testicular sonography numbers, the incidence of LCT appears much higher than expected, with some studies reporting up to 22% of small testicular nodules. Multimodal ultrasound using Doppler, Elastography, or injection of contrast media can provide crucial arguments to differentiate LCT from germ cell tumors. Multiparametric MRI is a second intention exam, but it allows for extraction of quantifiable data to assess the diagnosis of LCT. The aims of this article are to review the latest data regarding LCT imaging features, using multimodal ultrasound and multiparametric MRI, and to focus on the peculiar aspect of the testis of patients with Klinefelter's syndrome. The possibility of an LCT should be raised in front of a small hypoechoic tumor with a marked corbelling hypervascularization in an otherwise normal testicular pulp. Ultrasonographic modules, such as ultrasensitive Doppler, contrast-enhanced ultrasonography, or elastography, can be used to reinforce the suspicion of LCT. MRI provides objective data regarding vascularization and enhancement kinetics. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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33. Ultrasound Frequency Mixing for Enhanced Contrast Harmonic Imaging of Microbubbles.
- Author
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Karlinsky, Keren T. and Ilovitsh, Tali
- Subjects
- *
ARBITRARY waveform generators , *MICROBUBBLES , *ULTRASOUND contrast media , *CONTRAST-enhanced ultrasound , *IMAGING phantoms , *ULTRASONIC imaging , *IMAGE enhancement (Imaging systems) - Abstract
Microbubbles (MBs) serve as contrast agents in diagnostic ultrasound (US) imaging. Contrast harmonic imaging (CHI) of MBs takes advantage of their nonlinear properties that generate additional harmonic frequencies in the received spectrum. However, CHI suffers from limitations in terms of contrast, the signal-to-noise ratio, and artifacts. This article presents an enhanced, real-time, nonlinear imaging technique based on the excitation of MBs with a dual frequency waveform. The MBs trigger a frequency mixing effect that generates additional frequency components in the received spectrum; i.e., difference and sum frequencies, in addition to the standard harmonics, thus amplifying the MB’s nonlinear response and enhancing image contrast. In this real-time approach, two single frequency waveforms are superpositioned into a dual frequency transmission. The dual frequency waveform is incorporated into a standard pulse-inversion (PI) sequence and is transmitted by an array transducer using an arbitrary waveform generator (AWG) in a programmable US system. Upon receive, standard dynamic receive beamforming is used, without additional post processing. Numerical simulations using the Marmottant model are used to confirm the generation of the difference frequency in the MB’s backscattered echoes. The resulting image quality enhancement is demonstrated in a tissue-mimicking phantom containing MBs’ suspension. A maximal contrast improvement of 3.43 dB compared to standard PI was achieved, along with a reduction by 4.5 fold in the mechanical index (MI). [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
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34. Nomogram based on radiomics analysis of ultrasound images can improve preoperative BRAF mutation diagnosis for papillary thyroid microcarcinoma
- Author
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Jiajia Tang, Shitao Jiang, Jiaojiao Ma, Xuehua Xi, Huilin Li, Liangkai Wang, and Bo Zhang
- Subjects
Nomogram ,ultrasound (US) ,radiomics ,BRAF mutation ,papillary thyroid microcarcinoma (PTMC) ,Diseases of the endocrine glands. Clinical endocrinology ,RC648-665 - Abstract
BackgroundThe preoperative identification of BRAF mutation could assist to make appropriate treatment strategies for patients with papillary thyroid microcarcinoma (PTMC). This study aimed to establish an ultrasound (US) radiomics nomogram for the assessment of BRAF status.MethodsA total of 328 PTMC patients at the China-Japan Friendship Hospital between February 2019 and November 2021 were enrolled in this study. They were randomly divided into training (n = 232) and validation (n = 96) cohorts. Radiomics features were extracted from the US images. The least absolute shrinkage and selection operator (LASSO) regression was applied to select the BRAF status-related features and calculate the radiomics score (Rad-score). Univariate and multivariate logistic regression analyses were subsequently performed to identify the independent factors among Rad-score and conventional US features. The US radiomics nomogram was established and its predictive performance was evaluated via discrimination, calibration, and clinical usefulness in the training and validation sets.ResultsMultivariate analysis indicated that the Rad-score, composition, and aspect ratio were independent predictive factors of BRAF status. The US radiomics nomogram which incorporated the three variables showed good calibration. The discrimination of the US radiomics nomogram showed better discriminative ability than the conventional US model both in the training set (AUC 0.685 vs. 0.592) and validation set (AUC 0.651 vs. 0.622). Decision curve analysis indicated the superior clinical applicability of the nomogram compared to the conventional US model.ConclusionsThe US radiomics nomogram displayed better performance than the conventional US model in predicting BRAF mutation in patients with PTMC.
- Published
- 2022
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35. Incidental Focal Spleen Lesions: Integrated Imaging and Pattern Recognition Approach to the Differential Diagnosis
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Antonio Corvino, Vincenza Granata, Domenico Tafuri, Giulio Cocco, and Orlando Catalano
- Subjects
spleen ,incidental findings ,ultrasound (US) ,computed tomography (CT) ,magnetic resonance imaging (MRI) ,Positron Emission Tomography (PET) ,Medicine (General) ,R5-920 - Abstract
Spleen lesions and pseudolesions, detected incidentally in imaging, are not uncommon and may require further work-up. The imaging appearance of focal splenic lesions (FSLs) may not be pathognomonic, because of considerably overlapping features. Consequently, all imaging techniques lack specificity to fully characterize FSLs. Clinical correlation is mandatory, so as, first of all, to categorize the patient as having or not having a history of solid or hematologic malignancy. Nowadays, many patients have old imaging studies available for comparison and, consequently, it is important to understand if the lesion was previously present or not, and if the size is the same or has changed. In the absence of comparison studies, and with a lack of imaging features of benignity, further investigation may be necessary, using PET, biopsy, or short-term follow-up. Some algorithms have been proposed to manage incidental FSLs; however, none of these strategies has been validated by prospective studies to date. In this review we illustrate the topic of incidental FSLs and we analyze a number of published algorithms.
- Published
- 2023
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36. Differentiation of Thyroid Nodules (C-TIRADS 4) by Combining Contrast-Enhanced Ultrasound Diagnosis Model With Chinese Thyroid Imaging Reporting and Data System.
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Zhu, Tiantong, Chen, Jiahui, Zhou, Zimo, Ma, Xiaofen, and Huang, Ying
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CONTRAST-enhanced ultrasound ,THYROID nodules ,THYROID gland ,THYROID cancer ,DIAGNOSIS ,FACTOR analysis - Abstract
Objectives: To establish a contrast-enhanced ultrasound (CEUS) diagnostic schedule by CEUS analysis of thyroid nodules of C-TIRADS 4. To establish a CEUS-TIRADS diagnostic model to differentiate thyroid nodules (C-TIRADS 4) by combining CEUS with Chinese thyroid imaging reporting and data system (C-TIRADS). Methods: A total of 228 thyroid nodules (C-TIRADS 4) were estimated by CEUS. The arrival time, enhancement degree, enhancement homogeneity, enhancement pattern, enhancement ring, and wash-out time were analyzed in CEUS for all of the nodules. Multivariate factors logistic analysis was performed and a CEUS diagnostic schedule was established. If the nodule had a regular hyper-enhancement ring or got a score of less than 2 in CEUS analysis, CEUS-TIRADS subtracted 1 category. If the nodule got a score of 2 in the CEUS schedule, the CEUS-TIRADS category remained the same as before. If the nodule got a score of more than 2 in the CEUS schedule, CEUS-TIRADS added 1 category. When it reflected an absent enhancement in CEUS, the nodule was judged as CEUS-TIRADS 3. All of the C-TIRADS 4 nodules were re-graded by CEUS-TIRADS. We then compare the diagnosis performance of C-TIRADS, CEUS, and CEUS-TIRADS by sensitivity, specificity, and accuracy. Results: Among the 228 C-TIRADS 4 nodules, 69 were determined as C-TIRADS 4a, 114 were C-TIRADS 4b, and 45 were C-TIRADS 4c. The sensitivity, specificity, and accuracy of C-TIRADS were 93.1%, 55.3%, and 74.6% respectively. The area under the curve was 0.753. Later arrival time, hypo-enhancement, heterogeneous enhancement, centripetal enhancement, and rapid washout were risk factors of malignancy in multivariate analysis. The sensitivity, specificity, and accuracy of CEUS were 78.7%, 87.5%, and 83.3% respectively. The area under the curve was 0.803. By CEUS-TIRADS diagnostic model combining CEUS with C-TIRADS, a total of 127 cases were determined as malignancy (111 were malignant and 16 were benign) and 101 were diagnosed as benign ones (5 were malignant and 96 were benign). The sensitivity, specificity, and accuracy of CEUS-TIRADS were 95.7%, 85.7%, and 92.1% respectively. The area under the curve was 0.916. The diagnostic performance of CEUS-TIRADS was significantly better than CEUS and C-TIRADS. The difference was statistically significant (P<0.05). Conclusions: The diagnostic schedule of CEUS could get better diagnostic performance than US in the differentiation of thyroid nodules. The CEUS-TIRADS combining CEUS analysis with C-TIRADS could make up for the deficient sensibility of C-TIRADS, showing a better diagnostic performance than US and CEUS. [ABSTRACT FROM AUTHOR]
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- 2022
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37. Biomimetic nanobubbles for triple-negative breast cancer targeted ultrasound molecular imaging.
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Jugniot, Natacha, Massoud, Tarik F., Dahl, Jeremy J., and Paulmurugan, Ramasamy
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TRIPLE-negative breast cancer , *ULTRASONIC imaging , *BREAST , *MEDICAL care , *CELL membranes , *IMMUNOFLUORESCENCE - Abstract
Triple-negative breast cancer (TNBC) is a highly heterogeneous breast cancer subtype with poor prognosis. Although anatomical imaging figures prominently for breast lesion screening, TNBC is often misdiagnosed, thus hindering early medical care. Ultrasound (US) molecular imaging using nanobubbles (NBs) capable of targeting tumor cells holds great promise for improved diagnosis and therapy. However, the lack of conventional biomarkers in TNBC impairs the development of current targeted agents. Here, we exploited the homotypic recognition of cancer cells to synthesize the first NBs based on TNBC cancer cell membrane (i.e., NBCCM) as a targeted diagnostic agent. We developed a microfluidic technology to synthesize NBCCM based on the self-assembly property of cell membranes in aqueous solutions. In vitro, optimal NBCCM had a hydrodynamic diameter of 683 ± 162 nm, showed long-lasting US contrast enhancements and homotypic affinity. In vivo, we demonstrated that NBCCM showed increased extravasation and retention in a TNBC mouse model compared to non-targeted NBs by US molecular imaging. Peak intensities and areas under the curves from time-intensity plots showed a significantly enhanced signal from NBCCM compared to non-targeted NBs (2.1-fold, P = 0.004, and, 3.6-fold, P = 0.0009, respectively). Immunofluorescence analysis further validated the presence of NBCCM in the tumor microenvironment. Circumventing the challenge for universal cancer biomarker identification, our approach could enable TNBC targeting regardless of tumor tissue heterogeneity, thus improving diagnosis and potentially gene/drug targeted delivery. Ultimately, our approach could be used to image many cancer types using biomimetic NBs prepared from their respective cancer cell membranes. [ABSTRACT FROM AUTHOR]
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- 2022
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38. A Prototype System With Custom-Designed RX ICs for Contrast-Enhanced Ultrasound Imaging.
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Zhou, Meiyi, Chen, Peiran, Pollet, Andreas M. A. O., Ouzounov, Sotir, den Toonder, Jaap M. J., Mischi, Massimo, Cantatore, Eugenio, and Harpe, Pieter
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CONTRAST-enhanced ultrasound , *ULTRASONIC imaging , *ULTRASOUND contrast media , *BANDPASS filters , *ULTRASONIC transducers , *ULTRASONIC arrays - Abstract
This work presents a prototype system based on a multichannel receiving (RX) integrated circuit (IC) for contrast-enhanced ultrasound (CEUS) imaging. The RX IC is implemented in a 40-nm low-voltage CMOS technology and is designed to interface to a capacitive micromachined ultrasonic transducer array. To enable a direct connection of the RX electronics to the transducer, an analog multiplexer with on-chip protection circuitry is developed. Stress tests confirm the reliability of this arrangement when combined with a high-voltage pulser. The RX IC is equipped with a highly programmable bandpass filter to capture harmonic signals from ultrasound contrast agents (UCAs) while suppressing fundamental components. In order to examine the impact of analog front-end (AFE) bandpass filtering, in vitro acoustic experiments are performed with UCAs. A spatial resolution analysis suggests that the AFE bandpass filtering combined with a pulse inversion (PI) technique can improve the lateral resolution by 38% or 9% compared to the original full-bandwidth approach or a stand-alone PI approach, respectively, while the impact on axial resolution is negligible. A phantom study shows that compared to digital bandpass filtering, the AFE bandpass filtering enables better use of the dynamic range of the RX electronics, resulting in better generalized contrast-to-noise ratio from 0.44/0.53 to 0.57/0.68 without or with PI. [ABSTRACT FROM AUTHOR]
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- 2022
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39. Differentiation of Thyroid Nodules (C-TIRADS 4) by Combining Contrast-Enhanced Ultrasound Diagnosis Model With Chinese Thyroid Imaging Reporting and Data System
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Tiantong Zhu, Jiahui Chen, Zimo Zhou, Xiaofen Ma, and Ying Huang
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Chinese thyroid imaging reporting and data system(C-TIRADS) ,ultrasound (US) ,contrast-enhanced ultrasound (CEUS) ,thyroid nodules ,differentiation ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
ObjectivesTo establish a contrast-enhanced ultrasound (CEUS) diagnostic schedule by CEUS analysis of thyroid nodules of C-TIRADS 4. To establish a CEUS-TIRADS diagnostic model to differentiate thyroid nodules (C-TIRADS 4) by combining CEUS with Chinese thyroid imaging reporting and data system (C-TIRADS).MethodsA total of 228 thyroid nodules (C-TIRADS 4) were estimated by CEUS. The arrival time, enhancement degree, enhancement homogeneity, enhancement pattern, enhancement ring, and wash-out time were analyzed in CEUS for all of the nodules. Multivariate factors logistic analysis was performed and a CEUS diagnostic schedule was established. If the nodule had a regular hyper-enhancement ring or got a score of less than 2 in CEUS analysis, CEUS-TIRADS subtracted 1 category. If the nodule got a score of 2 in the CEUS schedule, the CEUS-TIRADS category remained the same as before. If the nodule got a score of more than 2 in the CEUS schedule, CEUS-TIRADS added 1 category. When it reflected an absent enhancement in CEUS, the nodule was judged as CEUS-TIRADS 3. All of the C-TIRADS 4 nodules were re-graded by CEUS-TIRADS. We then compare the diagnosis performance of C-TIRADS, CEUS, and CEUS-TIRADS by sensitivity, specificity, and accuracy.ResultsAmong the 228 C-TIRADS 4 nodules, 69 were determined as C-TIRADS 4a, 114 were C-TIRADS 4b, and 45 were C-TIRADS 4c. The sensitivity, specificity, and accuracy of C-TIRADS were 93.1%, 55.3%, and 74.6% respectively. The area under the curve was 0.753. Later arrival time, hypo-enhancement, heterogeneous enhancement, centripetal enhancement, and rapid washout were risk factors of malignancy in multivariate analysis. The sensitivity, specificity, and accuracy of CEUS were 78.7%, 87.5%, and 83.3% respectively. The area under the curve was 0.803. By CEUS-TIRADS diagnostic model combining CEUS with C-TIRADS, a total of 127 cases were determined as malignancy (111 were malignant and 16 were benign) and 101 were diagnosed as benign ones (5 were malignant and 96 were benign). The sensitivity, specificity, and accuracy of CEUS-TIRADS were 95.7%, 85.7%, and 92.1% respectively. The area under the curve was 0.916. The diagnostic performance of CEUS-TIRADS was significantly better than CEUS and C-TIRADS. The difference was statistically significant (P
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- 2022
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40. Antenatal ultrasound needs-analysis survey of Australian rural/remote healthcare clinicians: recommendations for improved service quality and access
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Bidner, Amber, Bezak, Eva, and Parange, Nayana
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- 2023
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41. In Vivo Ultrasound Localization Microscopy Imaging of the Kidney’s Microvasculature With Block-Matching 3-D Denoising.
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Lei, Shuang, Zhang, Ge, Zhu, Benpeng, Long, Xiaojing, Jiang, Zhenzhen, Liu, Yang, Hu, Dehong, Sheng, Zonghai, Zhang, Qi, Wang, Congzhi, Gao, Zeping, Zheng, Hairong, and Ma, Teng
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MICROSCOPY , *IMAGE denoising , *SINGULAR value decomposition , *HIGH resolution imaging , *MICROBUBBLE diagnosis , *ULTRASONIC imaging , *RHESUS monkeys - Abstract
Structural abnormalities and functional changes of renal microvascular networks play a significant pathophysiologic role in the occurrence of kidney diseases. Super-resolution ultrasound imaging has been successfully utilized to visualize the microvascular network and provide valuable diagnostic information. To prevent the burst of microbubbles, a lower mechanical index (MI) is generally used in ultrasound localization microscopy (ULM) imaging. However, high noise levels lead to incorrect signal localizations in relatively low-MI settings and deep tissue. In this study, we implemented a block-matching 3-D (BM3D) image-denoising method, after the application of singular value decomposition filtering, to further suppress the noise at various depths. The in vitro flow-phantom results show that the BM3D method helps the significant reduction of the error localizations, thus improving the localization accuracy. In vivo rhesus macaque experiments help conclude that the BM3D method improves the resolution more than other image-based denoising techniques, such as the nonlocal means method. The obtained clutter-filtered images with fewer incorrect localizations can enable robust ULM imaging, thus helping in establishing an effective diagnostic tool. [ABSTRACT FROM AUTHOR]
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- 2022
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42. Multiperspective Bistatic Ultrasound Imaging and Elastography of the Ex Vivo Abdominal Aorta.
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van Hal, Vera H. J., De Hoop, Hein, Muller, Jan-Willem, van Sambeek, Marc R. H. M., Schwab, Hans-Martin, and Lopata, Richard G. P.
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ABDOMINAL aorta , *ULTRASONIC imaging , *AORTIC rupture , *ELASTOGRAPHY , *MIMO radar , *BISTATIC radar - Abstract
Knowledge of aneurysm geometry and local mechanical wall parameters using ultrasound (US) can contribute to a better prediction of rupture risk in abdominal aortic aneurysms (AAAs). However, aortic strain imaging using conventional US is limited by the lateral lumen–wall contrast and resolution. In this study, ultrafast multiperspective bistatic (MP BS) imaging is used to improve aortic US, in which two curved array transducers receive simultaneously on each transmit event. The advantage of such bistatic US imaging on both image quality and strain estimations was investigated by comparing it to single-perspective monostatic (SP MS) and MP monostatic (MP MS) imaging, i.e., alternately transmitting and receiving with either transducer. Experimental strain imaging was performed in US simulations and in an experimental study on porcine aortas. Different compounding strategies were tested to retrieve the most useful information from each received US signal. Finally, apart from the conventional sector grid in curved array US imaging, a polar grid with respect to the vessel’s local coordinate system is introduced. This new reconstruction method demonstrated improved displacement estimations in aortic US. The US simulations showed increased strain estimation accuracy using MP BS imaging bistatic imaging compared to MP MS imaging, with a decrease in the average relative error between 41% and 84% in vessel wall regions between transducers. In the experimental results, the mean image contrast-to-noise ratio was improved by up to 8 dB in the vessel wall regions between transducers. This resulted in an increased mean elastographic signal-to-noise ratio by about 15 dB in radial strain and 6 dB in circumferential strain. [ABSTRACT FROM AUTHOR]
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- 2022
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43. The diagnostic value of ultrasonography in detection of different types of thyroid nodules
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Ahmed Youssef, Mohamed Hesham Abd-Elmonem, Rania Ahmed Mohamed Ghazy, Mohamed Mahmoud El Shafei, and Mohamed Zahran
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Ultrasound (US) ,Fine-needle aspiration biopsy (FNAB) ,Thyroid nodule ,Microcalcification ,Otorhinolaryngology ,RF1-547 - Abstract
Abstract Background This article discusses the importance of high frequency ultrasonography in detection of different types of thyroid nodules considering only the histopathological examination of the surgical specimens as the final diagnosis. We studied 50 patients referred to ENT clinic with a thyroid nodule. Ultrasonography and ultrasound-guided fine-needle aspiration biopsy were done to all the patients. Thyroid surgery was done according to FNAB results. Result From 50 thyroid specimens, the US could predict the malignancy in 18 specimens. By histopathology, only 16 specimens were malignant, and 34 were benign thyroid disease. The sensitivity, specificity, and accuracy of US were 100%, 94.12%, and 96% respectively. The most suspicious ultrasongraphic feature was microcalcification followed by taller than wider (T ˃ W). Conclusion High frequency ultrasound is a very important tool to predict the malignant possibility during thyroid nodule evaluation.
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- 2020
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44. Multimodality Imaging Findings of Breast Metastases from Malignant Melanoma: A Case Series
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Marlina Tanty Ramli Hamid, Wai Yee Chan, Dian Noriza Eddy Suryono, Noor Laily Syakimah Saidi, Anushya Vijayananthan, Jayalakshmi Pailoor, and Kartini Rahmat
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melanoma metastasis ,mammogram (mmg) ,ultrasound (us) ,computed tomography (ct) ,magnetic resonance imaging (mri) ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Breast metastases stemming from extramammary malignancies are rare, occurring in approximately 1.3–2.7% of breast malignancies. The most prevalent are metastases belonging to the primary carcinoma of the contralateral breast, followed by lymphoma and malignant melanoma. Breast metastasis is to be suspected in patients with previous history of malignant melanoma who present with a breast mass. Distinguishing metastasis from primary breast neoplasms is a challenging task. Accurate diagnosis is crucial because the prognosis and management differ significantly between primary and secondary malignancies of the breast. Imaging features are non-specific on mammography and ultrasound. There have been several reports on the magnetic resonance imaging (MRI) characteristics of breast metastasis originating from malignant melanoma; however, only few studies have described the diffusion weighted imaging (DWI) feature and the apparent diffusion coefficient (ADC) value. In this study, we report the multimodality imaging features of three cases of breast metastases from malignant melanoma. We particularly focus on MRI findings, such as DWI feature and ADC value and compare them with the MRI features reported in the literature.
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- 2020
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45. VOLAR GANGLION CYST OF THE WRIST SIMULATING A RADIAL ARTERY PSEUDOANEURYSM: A CASE REPORT
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Antonio Corvino
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ganglion cyst ,pseudoaneurysm ,ultrasound (us) ,magnetic resonance imaging (mri) ,wrist ,Medicine (General) ,R5-920 - Abstract
Pseudoaneurysms (PAs) of the radial artery are common following percutaneous cardiac catheterization. Ganglion cysts (GCs) are also a commonly identified entity in patients with history of trauma, osteoarthritis or inflammatory joint diseases. It can be challenging to differentiate a GC from a PA of the radial artery if the ganglion is located adjacent to the radial artery, especially when the medical history is suspicious. We herein present a rare case of a GC in the wrist simulating an iatrogenic PA of the radial artery in an elderly patient who had undergone to a recent diagnostic cardiac catheterization at the same site. Clinicians should be aware of the diagnostic techniques for the study of superficial lesions of the wrist in order to recognize the possible pathologies in the differential diagnosis.
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- 2020
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46. Using the GoogLeNet deep-learning model to distinguish between benign and malignant breast masses based on conventional ultrasound: a systematic review and meta-analysis.
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Wang J, Tong J, Li J, Cao C, Wang S, Bi T, Zhu P, Shi L, Deng Y, Ma T, Hou J, and Cui X
- Abstract
Background: Breast cancer is one of the most common malignancies in women worldwide, and early and accurate diagnosis is crucial for improving treatment outcomes. Conventional ultrasound (CUS) is a widely used screening method for breast cancer; however, the subjective nature of interpreting the results can lead to diagnostic errors. The current study sought to estimate the effectiveness of using a GoogLeNet deep-learning convolutional neural network (CNN) model to identify benign and malignant breast masses based on CUS., Methods: A literature search was conducted of the Embase, PubMed, Web of Science, Wanfang, China National Knowledge Infrastructure (CNKI), and other databases to retrieve studies related to GoogLeNet deep-learning CUS-based models published before July 15, 2023. The diagnostic performance of the GoogLeNet models was evaluated using several metrics, including pooled sensitivity (PSEN), pooled specificity (PSPE), the positive likelihood ratio (PLR), the negative likelihood ratio (NLR), the diagnostic odds ratio (DOR), and the area under the curve (AUC). The quality of the included studies was evaluated using the Quality Assessment of Diagnostic Accuracy Studies Scale (QUADAS). The eligibility of the included literature were independently searched and assessed by two authors., Results: All of the 12 studies that used pathological findings as the gold standard were included in the meta-analysis. The overall average estimation of sensitivity and specificity was 0.85 [95% confidence interval (CI): 0.80-0.89] and 0.86 (95% CI: 0.78-0.92), respectively. The PLR and NLR were 6.2 (95% CI: 3.9-9.9) and 0.17 (95% CI: 0.12-0.23), respectively. The DOR was 37.06 (95% CI: 20.78-66.10). The AUC was 0.92 (95% CI: 0.89-0.94). No obvious publication bias was detected., Conclusions: The GoogLeNet deep-learning model, which uses a CNN, achieved good diagnostic results in distinguishing between benign and malignant breast masses in CUS-based images., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-24-679/coif). All authors report that this work was supported by the Tianshan Young Talent Scientific and Technological Innovation Team: Innovative Team for Research on Prevention and Treatment of High-incidence Diseases in Central Asia (No. 2023TSYCTD0020), the National Natural Science Foundation of China (No. 82060318), the Corps Science and Technology Key Project (No. 2022CB002-04), the First Affiliated Hospital of Shihezi University School of Medicine Youth Fund Project (No. QN202107), and The First Affiliated Hospital of Shihezi University School of Medicine Youth Fund Project (No. QN202126). The authors have no other conflicts of interest to declare., (2024 AME Publishing Company. All rights reserved.)
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- 2024
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47. Evaluating the stage of deep vein thrombosis: the diagnostic accuracy of shear wave elastography and super-microvascular imaging.
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Peng L, Liu Y, Lv C, Shen W, Wu Y, Zhang J, and Fu Z
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Background: Assessing the age of deep vein thrombosis (DVT) is crucial for guiding treatment approaches. Two-dimensional shear-wave elastography (2D-SWE) and super-microvascular imaging (SMI), as emerging techniques for tissue elasticity assessment and intrathrombus microvascular analysis, are pivotal for accurate thrombus age determination. This research endeavors to classify DVT into acute, subacute, and chronic ages utilizing these imaging methods., Methods: The study is a prospective, single-center, inpatient investigation that utilized convenience sampling for participant recruitment. Patients with a symptom duration of <6 months who were found to have lower-extremity DVT on ultrasound (US) between January 2021 and March 2022 after craniocerebral trauma (CT) or bone injury (BI) operations were included in this study. Participants were divided into three groups based on the duration of DVT, measured from the first diagnosis of thrombosis by US to the follow-up with 2D-SWE and SMI: acute (≤14 days), subacute (15-30 days), and chronic (31 days to 6 months) All patients underwent 2D-SWE and SMI using an Aplio i700 Ultrasound System equipped with a PLT-1005BT line array probe. Diagnostic performance was assessed using the area under the receiver operating characteristic (ROC) curve., Results: The maximum value of the elastic modulus for DVT (DVT_Emax), the mean value of the elastic modulus for DVT (DVT_Emean), and SMI's flow distribution scoring pattern for DVT (SMI_scoring) emerged as significant predictors for acute and chronic, with high area under the ROC curve (AUC) of acute [AUC (95% confidential interval): 0.95 (0.89-0.97), 0.96 (0.91-0.98), 0.93 (0.88-0.97) in 39 patients] and chronic [AUC (95% confidential interval): 0.88 (0.81-0.93), 0.94 (0.88-0.97), 0.91 (0.84-0.95) in 51 patients], respectively. However, these indices had lower efficacy for subacute prediction [AUC (95% confidential interval): 0.51 (0.42-0.60), 0.54 (0.46-0.63), 0.53 (0.44-0.62), in 47 patients]. Combining DVT_Emean with SMI_scoring improved performance in predicting subacute: 0.90 (0.83-0.94) than related features alone., Conclusions: Both 2D-SWE and SMI can be used to assess acute and chronic DVT in patients with CT and BI after surgeries. This combination is a promising adjunctive technique for identifying the subacute phase of DVT in these patients., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-23-1822/coif). All authors report that this research was funded by Tai’an Innovation Development Program for Science and Technology (Nos. 2021NS141 and 2021NS169). The authors have no other conflicts of interest to declare., (2024 Quantitative Imaging in Medicine and Surgery. All rights reserved.)
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- 2024
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48. Four-dimensional computed tomography and ultrasonography for prediction of pathological parathyroid location: a retrospective review of a single surgeon's patients at a single institution.
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Hairston H, Gardner JR, Gibson AC, Wright C, Small M, King D, Fitzgerald R, Spencer HJ, Bodenner DL, and Stack BC Jr
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Background: Pre-operative imaging is a well-established practice for managing hyperparathyroidism with the plan for excision; however, there is a paucity of information regarding the success rate of concordant imaging studies. Our goal was to compare the accuracy (sensitivity) of four-dimensional computed tomography (4DCT) and ultrasound (US) when predicting the side and quadrant of parathyroid lesions, confirmed with surgical location (from a single surgeon)., Methods: A retrospective review of 437 patients from a single surgeon undergoing parathyroidectomy from December 2013 to January 2020 at an academic medical center was performed. Masses >5 mm in dimension in eutopic parathyroid locations were identified as possible parathyroid lesions on 4DCT. A unique codified system was utilized to accurately record imaging results for each modality and compared to surgical findings., Results: Four hundred and thirty-seven patients underwent parathyroid surgery, of those 431 underwent 4DCT, 413 underwent US, and 408 underwent both. 4DCT accurately lateralized lesions in 319 (74.0%; N=431). US lateralized lesions in 265 (64.2%; N=413). The sensitivity for lateralization was 81.2% and 69.9% for 4DCT and US, respectively., Conclusions: 4DCT and US identify the majority of parathyroid lesions. 4DCT outperformed US in lateralization yet both modalities remain useful and are complimentary in planning for successful parathyroidectomy. Newer imaging approaches such as
18 F-choline positron emission tomography/computed tomography (PET/CT) and artificial intelligence as an augmentation to imaging review may play in role to identify parathyroid adenomas/hyperplasia, but their roles have yet to be clearly defined., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://gs.amegroups.com/article/view/10.21037/gs-24-141/coif). R.F. reports that since 2017, he has been employed as a physician by Radiology Consultants of Little Rock. Radiology Consultants and his work with the group have no relationship, financial or otherwise, to this manuscript. The other authors have no conflicts of interest to declare., (2024 Gland Surgery. All rights reserved.)- Published
- 2024
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49. Diagnostic efficacy of the contrast-enhanced ultrasound thyroid imaging reporting and data system classification for benign and malignant thyroid nodules.
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Yang YP, Zhang GL, Zhou HL, Dai HX, Huang X, Liu LJ, Xie J, Wang JX, Li HJ, Liang X, Yuan Q, Zeng YH, and Xu XH
- Abstract
Background: The contrasted-enhanced ultrasound thyroid imaging reporting and data system (CEUS TI-RADS) is the first international risk stratification system for thyroid nodules based on conventional ultrasound (US) and CEUS. This study aimed to evaluate the diagnostic efficacy of CEUS TI-RADS for benign and malignant thyroid nodules and to assess the related interobserver agreement., Methods: The study recruited 433 patients who underwent thyroid US and CEUS between January 2019 and June 2023 at the Affiliated Hospital of Guangdong Medical University. A retrospective analysis of 467 thyroid nodules confirmed by fine-needle aspiration (FNA) and/or surgery was performed. Further, a CEUS TI-RADS classification was assigned to each thyroid nodule based on the CEUS TI-RADS scoring criteria for the US and CEUS features of the nodule. The nodules were grouped based on their sizes as follows: size ≤1 cm, group A; size >1 and ≤4 cm, group B; and size >4 cm, group C. Multivariate logistic regression was used to analyze independent risk factors for malignant thyroid nodules. Pathological assessment was the reference standard for establishing the sensitivity (SEN), specificity (SPE), accuracy (ACC), positive predictive value (PPV), and negative predictive value (NPV) of CEUS TI-RADS in diagnosing malignant thyroid nodules. The area under the curve (AUC) in the receiver operating characteristic (ROC) curve analysis was used to compare the diagnostic efficacy of the scoring system in predicting malignancy in three groups of nodules. The intragroup correlation coefficient (ICC) was adopted to assess the interobserver agreement of the CEUS TI-RADS score., Results: Out of the 467 thyroid nodules, 262 were malignant and 205 were benign. Logistic regression analysis revealed that the independent risk factors for malignant thyroid nodules included punctate echogenic foci (P<0.001), taller-than-wide shape (P=0.015), extrathyroidal invasion (P=0.020), irregular margins/lobulation (P=0.036), hypoechoicity on US (P=0.038), and hypoenhancement on CEUS (P<0.001). The AUC for the CEUS TI-RADS in diagnosing malignant thyroid nodules was 0.898 for all nodules, 0.795 for group A, 0.949 for group B, and 0.801 for group C, with the optimal cutoff values of the CEUS TI-RADS being 5 points, 6 points, 5 points, and 5 points, respectively. Among these groups of nodules, group B had the highest AUC, with the SEN, SPE, ACC, PPV, and NPV for diagnosing malignant nodules being 95.9%, 88.1%, 92.8%, 92.6%, and 93.2%, respectively. The ICC of the CEUS TI-RADS classification between senior and junior physicians was 0.862 (P<0.001)., Conclusions: In summary, CEUS TI-RADS demonstrated significant efficacy in distinguishing thyroid nodules. Nonetheless, there were variations in its capacity to detect malignant nodules across diverse sizes, and it demonstrate optimal performance in 1- to 4-cm nodules. These findings may serve as important insights for clinical diagnoses., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-24-457/coif). The authors have no conflicts of interest to declare., (2024 Quantitative Imaging in Medicine and Surgery. All rights reserved.)
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- 2024
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50. Deep-learning radiomics based on ultrasound can objectively evaluate thyroid nodules and assist in improving the diagnostic level of ultrasound physicians.
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Du H, Chen F, Li H, Wang K, Zhang J, Meng J, Li H, Xu X, Qu J, Wu R, Li J, Zhang M, Zhang F, and Zhu X
- Abstract
Background: The incidence rate of thyroid nodules has reached 65%, but only 5-15% of these modules are malignant. Therefore, accurately determining the benign and malignant nature of thyroid nodules can prevent unnecessary treatment. We aimed to develop a deep-learning (DL) radiomics model based on ultrasound (US), explore its diagnostic efficacy for benign and malignant thyroid nodules, and verify whether it improved the diagnostic level of physicians., Methods: We retrospectively included 1,076 thyroid nodules from 817 patients at three institutions. The radiomics and DL features of the US images were extracted and used to construct radiomics signature (Rad_sig) and deep-learning signature (DL_sig). A Pearson correlation analysis and least absolute shrinkage and selection operator (LASSO) regression analysis were used for feature selection. Clinical US semantic signature (C_US_sig) was constructed based on clinical information and US semantic features. Next, a combined model was constructed based on the above three signatures in the form of a nomogram. The model was constructed using a development set (institution 1: 719 nodules), and the model was evaluated using two external validation sets (institution 2: 74 nodules, and institution 3: 283 nodules). The performance of the model was assessed using decision curve analysis (DCA) and calibration curves. Furthermore, the C_US_sigs of junior physicians, senior physicians, and expers were constructed. The DL radiomics model was used to assist the physicians with different levels of experience in the interpretation of thyroid nodules., Results: In the development and validation sets, the combined model showed the highest performance, with areas under the curve (AUCs) of 0.947, 0.917, and 0.929, respectively. The DCA results showed that the comprehensive nomogram had the best clinical utility. The calibration curves indicated good calibration for all models. The AUCs for distinguishing between benign and malignant thyroid nodules by junior physicians, senior physicians, and experts were 0.714-0.752, 0.740-0.824, and 0.891-0.908, respectively; however, with the assistance of DL radiomics, the AUCs reached 0.858-0.923, 0.888-0.944, and 0.912-0.919, respectively., Conclusions: The nomogram based on DL radiomics had high diagnostic efficacy for thyroid nodules, and DL radiomics could assist physicians with different levels of experience to improve their diagnostic level., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at https://qims.amegroups.com/article/view/10.21037/qims-23-1597/coif). The authors have no conflicts of interest to declare., (2024 Quantitative Imaging in Medicine and Surgery. All rights reserved.)
- Published
- 2024
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