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Mitochondrial dysfunction and oxidative stress are involved in the development of contrast-induced acute kidney injury (CI-AKI). The present study aimed to reveal the role of transient receptor potential ankyrin 1 (TRPA1), an oxidative sensor, in CI-AKI. Trpa1PT−/− mice with Trpa1 conditionally knocked out in renal proximal tubular (PT) cells, Trpa1 overexpression mice (Trpa1-OE), and TRPA1 agonists and antagonists were used to study its function in a mouse model of iohexol-induced CI-AKI. We found that TRPA1 was functionally expressed in PT cells. Activation of TRPA1 with cinnamaldehyde or overexpression of Trpa1 remarkably ameliorated renal tubular injury and dysfunction in a mouse model of CI-AKI, while CI-AKI was significantly exacerbated in Trpa1PT−/− mice. Proteomics demonstrated that mouse kidneys with CI-AKI had downregulated proteins involved in mitochondrial dynamics and upregulated mitophagy-associated proteins. The beneficial effects of TRPA1 activation/overexpression on CI-AKI were associated with improved mitochondrial function, decreased mitochondrial fission and oxidative stress, enhanced mitophagy, and less apoptosis of renal tubular cells. TRPA1-induced decreases in mitochondrial fission were linked to upregulated fusion-related proteins (mitofusin 1, mitofusin 2 and optic atrophy 1) and downregulated fission mediator, phosphorylated dynamin-related protein 1 (Drp1). Importantly, inhibition of Drp1 with mitochondrial division inhibitor 1 improved CI-AKI. In addition, the decreased mitochondrial fission was also mediated by inactivation of AMP-activated protein kinase which mediates mitochondrial biogenesis. The findings suggest that TRPA1 plays a protective role in CI-AKI through regulating mitochondrial fission/fusion, biogenesis, and dysfunction. Activating TRPA1 may become novel therapeutic strategies for the prevention of CI-AKI. [Display omitted] • TRPA1 is functionally expressed in renal proximal tubular cells. • Activation or overexpression of TRPA1 in renal proximal tubule ameliorates CI-AKI. • The renal protective effects of TRPA1 are due to improved mitochondrial function. • TRPA1 inhibits mitochondrial fission and oxidative stress and enhances mitophagy. • TRPA1 improves mitochondrial function via the AMPK/DRP1 pathway. [ABSTRACT FROM AUTHOR]

Acute kidney injury (AKI) is a complication often observed in critically ill patients, indicating a worsening prognosis. However, factors predicting AKI in subarachnoid hemorrhage (SAH) patients are unclear. This study aims to elucidate the predictors of AKI occurrence. All patients with SAH admitted to the intensive care unit between 2013 and 2019 were included. Patients with very severe SAH who are unsuitable to receive aggressive treatment, those who previously received a contrast medium at another medical institution within 24 hours before admission, and those on maintenance dialysis were excluded. We retrospectively examined blood tests conducted upon admission, oral medications administered, and the total amount of contrast medium used after initiating treatment to investigate their association with AKI occurrence. Of the 254 SAH patients treated during the relevant period, 195 (median age 64 years, 72 males) met the inclusion/exclusion criteria, and 32 patients (16.3%) developed AKI. When multivariate analysis was performed using sex, uric acid level, and hemoglobin, which obtained P < 0.01 in the univariate analysis, as variables, only uric acid level was found as an independent predictor of AKI (odds ratio, 1.501; 95% confidence interval, 1.109–2.033, P value of 0.009). There was no difference in the occurrence of AKI between survivors and nonsurvivors (12/163 vs. 2/32, P = 0.824). AKI occurred in 16.3% of the patients with SAH. Patients who developed AKI had significantly higher uric acid levels. SAH with high uric acid levels warrants attention for AKI. [ABSTRACT FROM AUTHOR]

Coronary CT angiography (CCTA) has recently been established as a first-line test in patients with suspected coronary artery disease (CAD). Due to the increased use of CCTA, strategies to reduce radiation and contrast medium (CM) exposure are of high importance. The aim of this study was to evaluate the performance of automated tube voltage selection (ATVS)-adapted CM injection protocol for CCTA compared to a clinically established triphasic injection protocol in terms of image quality, radiation exposure, and CM administration Patients undergoing clinically indicated CCTA were prospectively enrolled from July 2021 to July 2023. Patients underwent CCTA using a modified triphasic CM injection protocol tailored to the tube voltage by the ATVS algorithm, in a range of 70 to 130 kV with a 10 kV interval. The injection protocol consisted of two phases of mixed CM and saline boluses with different proportions to assure a voltage-specific iodine delivery rate, followed by a third phase of saline flush. This cohort was compared to a control group identified retrospectively and scanned on the same CT system but with a standard triphasic CM protocol. Radiation and contrast dose, subjective and objective image quality (contrast-to-noise-ratio [CNR] and signal-to-noise-ratio [SNR]) were compared between the two groups. The final population consisted of 120 prospective patients matched with 120 retrospective controls, with 20 patients in each kV group. The 120 kV group was excluded from the statistical analysis due to insufficient sample size. A significant CM reduction was achieved in the prospective group overall (46.0 [IQR 37.0–52.0] vs. 51.3 [IQR 40.1–73.0] mL, p < 0.001) and at all kV levels too (all pairwise p < 0.001). There were no significant differences in radiation dose (6.13 ± 4.88 vs. 5.97 ± 5.51 mSv, p = 0.81), subjective image quality (median score of 4 [3–5] vs. 4 [3–5], p = 0.40), CNR, and SNR in the aorta and the left anterior descending coronary artery (all p > 0.05). ATVS-adapted CM injection protocol allows for diagnostic quality CCTA with reduced CM volume while maintaining similar radiation exposure, subjective and objective image quality. [ABSTRACT FROM AUTHOR]

Objective: The use of computed tomography (CT) in aquarium animals, including elasmobranchs, has increased dramatically. To take advantage of CT, contrast medium is used to enhance internal organs and provide contrast since elasmobranchs lack visceral fat. In this study, the contrast effects of iopamidol were examined for up to 260 days after intravenous administration to establish the time course of the CT values for the target organs in eight mature Cloudy Catsharks Scyliorhinus torazame. Methods: A micro‐CT system was used to measure the CT values of the designated region of interest in the target organs (ventricular cavity, kidneys, liver, gallbladder, ovarian follicles, uterine horn cavity) over time and the eggs laid, following administration of iopamidol (700 mg of iodine/kg). Result: The CT values of the ventricular cavity and kidneys peaked at 30 min and showed low values after day 22. The CT values for the liver increased over time and peaked at day 200, whereas values for the gallbladder and ovarian follicles peaked on day 6, with the gallbladder showing a low value and the ovarian follicles still showing a high value on day 260. Computed tomography images with identifiable enhancement within bilateral uterine horns were followed from days 1 to 35. The mean and maximum CT values of yolk and jelly in eggs laid after day 30 were significantly higher than the values for eggs laid up to day 29; embryonic development was confirmed in 88.7% of the eggs. Conclusion: There was no mortality or morbidity of the sharks during the experiment, indicating that the administration of iopamidol at 700 mg of iodine/kg did not result in any adverse effects for 260 days. This is the first study to describe the long‐term contrast effects of iopamidol, thus contributing new information about the application of contrast studies in Cloudy Catsharks. Impact statementIn elasmobranchs, which include species facing extinction, there is limited knowledge on diagnostic imaging of computed tomography (CT). Soft tissue organs require intravascular administration of a contrast medium for CT imaging, yet data on the contrast effects and duration have been unknown. In this study, conducting CT scans on a Cloudy Catshark over 260 days after contrast medium administration yielded practical new insights into the diagnostic imaging for elasmobranchs. [ABSTRACT FROM AUTHOR]

Atherosclerosis is a common vascular disease， which is characterized by lipid deposition and related inflammatory reactions. Vulnerable atherosclerotic plaque is the main pathological cause of acute cardiovascular events. Therefore， early detection and timely interventional treatment of vulnerable plaques are of clinical significance. Although a variety of clinical methods have been developed for the diagnosis and treatment of vulnerable plaques， the acute clinical events caused by vulnerable plaques frequently occur. Nanoparticles have shown huge potential in this regard. Nanoparticles are widely applied in imaging because their unique optical properties can efficiently label tissues and cells to detect the state of disease. Metal nanoparticles can achieve high-resolution imaging， which can also be used as drug delivery carriers to improve therapeutic effect. In this article， recent research progress in the use of nanoparticles in targeted diagnosis of vulnerable atherosclerotic plaques was reviewed， and the future development of nanoparticles in related fields and the challenges and opportunities for clinical transformation were also illustrated.

Contrast-induced encephalopathy (CIE) is a rare complication of angiography. According to our knowledge, the majority of CIE reports is imaging observations and rarely includes results of cerebrospinal fluid (CSF) tests. Furthermore, among the cases reporting the data for CSF testing, most of the results were normal. Here, we report a case of CIE presenting with significantly elevated levels of CSF protein. We found that the course of improvement in brain imaging findings was not consistent with the severity of clinical manifestations. The diffusion-weighted imaging (DWI) and apparent diffusion coefficient (ADC) sequences were normal. Considering the lack of convenient direct indicators to observe blood-brain barrier (BBB) function, changes in the levels of CSF protein may be related to BBB permeability and recovery and may serve as a potential prognostic marker. [ABSTRACT FROM AUTHOR]

Background: J waves may be augmented by coronary angiography (CAG) or intracoronary drug administration but the underlying mechanism is unknown. Purpose: The effect of intracoronary normal saline (NS) on J waves were investigated. Patients and methods: After the standard CAG using iopamidol (IopamiroR Inj), NS was injected into the right coronary artery in 10 patients with and eight patients without J waves at the baseline. The 12‐lead ECG was monitored, stored on a computer and retrieved later for measurement of the J wave amplitude before or during the coronary interventions. Results: J waves in leads II, III and aVF at baseline increased significantly in each lead during the right CAG and NS injection into the right coronary artery. The J wave changes were similar between the two interventions and distinct similar alterations were observed in the QRS complex. We postulated that the ischemic myocardium that was induced during CAG or intracoronary NS administration slowed the conduction velocity of depolarization in the perfusion territory and delayed the timing of J waves to appear. Then, the delayed appearance of J waves would be less opposed by electromotive force from other areas resulting in augmentation. Conclusion: J wave augmentation was observed during CAG and intracoronary NS administration. As a mechanism of augmentation, we postulated that contrast media and NS induce myocardial ischemia and delay the timing of J waves to a point of less opposition by electromotive force from other areas. Highlights: J wave augmentation has been reported during intracoronary injection of contrast media or drugs.The present study confirmed that normal saline alone was able to augment J waves.Mechanistically, coronary interventions using anoxic solutions can cause regional myocardial ischemia and reduce the conduction velocity of depolarization.Then, delayed J waves are less opposed by the electromotive force from remote areas which leads to augmentation.When a drug is diluted in normal saline and given intracoronarily, changes in J waves can be due to normal saline.The pathophysiological and clinical significance of J waves augmented during coronary interventions need to be established. [ABSTRACT FROM AUTHOR]

The implications of shorter scan time and lower tube voltage in the dual-source CT coronary angiography (CTCA) scan protocol necessitate the adaptation of contrast media (CM) injection parameters. This audit evaluates the coronary arteries' vascular attenuation and image quality by comparing the personalised patient protocol technology (P3T) contrast injection software with standard injection protocol. The secondary aim is to determine the relationship between CM volume and the patient's weight. A Siemens Somatom Definition Force CT Unit was used to scan 30 sets of patients between August 2020 and October 2020. Patients were selected retrospectively and separated into Standard Injection and P3T injection protocols. An experienced radiologist blinded to the groups reviewed the coronary vessels' contrast enhancement and image quality. Overall, the mean HU of all the main coronary artery vessels obtained from P3T injection software reached above 350 HU and was diagnostically sufficient. The mean attenuation at the proximal region of RCA in the 80–99 kg weight category was significantly higher in the P3T injection software than the standard injection protocol (p < 0.001). The CM volume proposed by P3T injection software for 40–59 kg was approximately 57 ± 5 mls, while 75 ml was used for the standard injection protocol. P3T injection software in CTCA resulted in an adequate diagnostic attenuation of coronary arteries (>350HU) in all weight groups, most effectively in the higher weight group, while maintaining diagnostic image quality. Further, the P3T software reduces CM volumes in lower-weight patients. P3T software enables reducing CM volume in lower-weight patients while improving vascular enhancement in CTCA scans in higher-weight patients. [ABSTRACT FROM AUTHOR]

Atherosclerosis is a common vascular disease, which is characterized by lipid deposition and related inflammatory reactions. Vulnerable atherosclerotic plaque is the main pathological cause of acute cardiovascular events. Therefore, early detection and timely interventional treatment of vulnerable plaques are of clinical significance. Although a variety of clinical methods have been developed for the diagnosis and treatment of vulnerable plaques, the acute clinical events caused by vulnerable plaques frequently occur. Nanoparticles have shown huge potential in this regard. Nanoparticles are widely applied in imaging because their unique optical properties can efficiently label tissues and cells to detect the state of disease. Metal nanoparticles can achieve high-resolution imaging, which can also be used as drug delivery carriers to improve therapeutic effect. In this article, recent research progress in the use of nanoparticles in targeted diagnosis of vulnerable atherosclerotic plaques was reviewed, and the future development of nanoparticles in related fields and the challenges and opportunities for clinical transformation were also illustrated. [ABSTRACT FROM AUTHOR]

Drug provocation tests (DPTs) are also used in some patients with a history of a contrast medium (CM)-hypersensitivity reaction. Since the use of contrast agents requires special knowledge that is present in radiology but not necessarily in allergology, this overview should close the knowledge gaps. The literature, and the package inserts of the industry dealing with DPTs in contrast hypersensitivity reactions was analyzed and the results presented. Historical analyses revealed that provocation tests were already done in the past, and called pre-testing. Due to disadvantages, this diagnostic tool was abandoned. A few years later, DPT was introduced as an innovative diagnostic procedure. The DPT has the 3 main disadvantages: a missing standardization, patients at risk (such as compromised renal function) are rarely taken into account, and a negative DPT does not exclude a subsequent CM reaction. DPTs (formerly called pre-testing) are a well-known method for diagnosing CM-related hypersensitivity reactions. Since the disadvantages of this diagnosis outweigh the advantages, we propose replacing DPT with routine contrast-enhanced imaging examination in radiology.

Abstract Objectives To collect real-world data about the knowledge and self-perception of young radiologists concerning the use of contrast media (CM) and the management of adverse drug reactions (ADR). Methods A survey (29 questions) was distributed to residents and board-certified radiologists younger than 40 years to investigate the current international situation in young radiology community regarding CM and ADRs. Descriptive statistics analysis was performed. Results Out of 454 respondents from 48 countries (mean age: 31.7 ± 4 years, range 25–39), 271 (59.7%) were radiology residents and 183 (40.3%) were board-certified radiologists. The majority (349, 76.5%) felt they were adequately informed regarding the use of CM. However, only 141 (31.1%) received specific training on the use of CM and 82 (18.1%) about management ADR during their residency. Although 266 (58.6%) knew safety protocols for handling ADR, 69.6% (316) lacked confidence in their ability to manage CM-induced ADRs and 95.8% (435) expressed a desire to enhance their understanding of CM use and handling of CM-induced ADRs. Nearly 300 respondents (297; 65.4%) were aware of the benefits of contrast-enhanced ultrasound, but 249 (54.8%) of participants did not perform it. The preferred CM injection strategy in CT parenchymal examination and CT angiography examination was based on patient’s lean body weight in 318 (70.0%) and 160 (35.2%), a predeterminate fixed amount in 79 (17.4%) and 116 (25.6%), iodine delivery rate in 26 (5.7%) and 122 (26.9%), and scan time in 31 (6.8%) and 56 (12.3%), respectively. Conclusion Training in CM use and management ADR should be implemented in the training of radiology residents. Critical relevance statement We highlight the need for improvement in the education of young radiologists regarding contrast media; more attention from residency programs and scientific societies should be focused on training about contrast media use and the management of adverse drug reactions. Key points • This survey investigated training of young radiologists about use of contrast media and management adverse reactions. • Most young radiologists claimed they did not receive dedicated training. • An extreme heterogeneity of responses was observed about contrast media indications/contraindications and injection strategy. Graphical Abstract

Gadolinium-based contrast agents (GBCAs) have helped to improve the role of magnetic resonance imaging (MRI) for the diagnosis and treatment of diseases. There are currently nine different commercially available gadolinium-based contrast agents (GBCAs) that can be used for body MRI cases, and which are classifiable according to their structures (cyclic or linear) or biodistribution (extracellular-space agents, target/specific-agents, and blood-pool agents). The aim of this review is to illustrate the commercially available MRI contrast agents, their effect on imaging, and adverse reaction on the body, with the goal to lead to their proper selection in different clinical contexts. When we have to choose between the different GBCAs, we have to consider several factors: (1) safety and clinical impact; (2) biodistribution and diagnostic application; (3) higher relaxivity and better lesion detection; (4) higher stability and lower tissue deposit; (5) gadolinium dose/concentration and lower volume injection; (6) pulse sequences and protocol optimization; (7) higher contrast-to-noise ratio at 3.0 T than at 1.5 T. Knowing the patient's clinical information, the relevant GBCAs properties and their effect on body MRI sequences are the key features to perform efficient and high-quality MRI examination. [ABSTRACT FROM AUTHOR]

Free-running 5D whole-heart coronary MR angiography (MRA) is gaining in popularity because it reduces scanning complexity by removing the need for specific slice orientations, respiratory gating, or cardiac triggering. At 3T, a gradient echo (GRE) sequence is preferred in combination with contrast injection. However, neither the injection scheme of the gadolinium (Gd) contrast medium, the choice of the RF excitation angle, nor the dedicated image reconstruction parameters have been established for 3T GRE free-running 5D whole-heart coronary MRA. In this study, a Gd injection scheme, RF excitation angles of lipid-insensitive binominal off-resonance RF excitation (LIBRE) pulse for valid fat suppression and continuous data acquisition, and compressed-sensing reconstruction regularization parameters were optimized for contrast-enhanced free-running 5D whole-heart coronary MRA using a GRE sequence at 3T. Using this optimized protocol, contrast-enhanced free-running 5D whole-heart coronary MRA using a GRE sequence is feasible with good image quality at 3T. [ABSTRACT FROM AUTHOR]

Objectives: To collect real-world data about the knowledge and self-perception of young radiologists concerning the use of contrast media (CM) and the management of adverse drug reactions (ADR). Methods: A survey (29 questions) was distributed to residents and board-certified radiologists younger than 40 years to investigate the current international situation in young radiology community regarding CM and ADRs. Descriptive statistics analysis was performed. Results: Out of 454 respondents from 48 countries (mean age: 31.7 ± 4 years, range 25–39), 271 (59.7%) were radiology residents and 183 (40.3%) were board-certified radiologists. The majority (349, 76.5%) felt they were adequately informed regarding the use of CM. However, only 141 (31.1%) received specific training on the use of CM and 82 (18.1%) about management ADR during their residency. Although 266 (58.6%) knew safety protocols for handling ADR, 69.6% (316) lacked confidence in their ability to manage CM-induced ADRs and 95.8% (435) expressed a desire to enhance their understanding of CM use and handling of CM-induced ADRs. Nearly 300 respondents (297; 65.4%) were aware of the benefits of contrast-enhanced ultrasound, but 249 (54.8%) of participants did not perform it. The preferred CM injection strategy in CT parenchymal examination and CT angiography examination was based on patient's lean body weight in 318 (70.0%) and 160 (35.2%), a predeterminate fixed amount in 79 (17.4%) and 116 (25.6%), iodine delivery rate in 26 (5.7%) and 122 (26.9%), and scan time in 31 (6.8%) and 56 (12.3%), respectively. Conclusion: Training in CM use and management ADR should be implemented in the training of radiology residents. Critical relevance statement: We highlight the need for improvement in the education of young radiologists regarding contrast media; more attention from residency programs and scientific societies should be focused on training about contrast media use and the management of adverse drug reactions. Key points: • This survey investigated training of young radiologists about use of contrast media and management adverse reactions. • Most young radiologists claimed they did not receive dedicated training. • An extreme heterogeneity of responses was observed about contrast media indications/contraindications and injection strategy. [ABSTRACT FROM AUTHOR]

Simple Summary: The increased detection of pancreatic cysts in recent years has triggered extensive diagnostic investigations to clarify their potential risk of malignancy, resulting in a large number of patients undergoing numerous imaging follow-up studies for many years. Therefore, there is a growing need for optimization of the current surveillance protocol to provide a practical and reasonable solution in the face of an ever-growing demand. The aim of this paper is to discuss the current available evidence on whether the implementation of unenhanced abbreviated-MRI (A-MRI) protocols for cystic pancreatic lesion surveillance could improve healthcare economics and reduce waiting lists in clinical practice without significantly reducing diagnostic accuracy. The increased detection of pancreatic cysts in recent years has triggered extensive diagnostic investigations to clarify their potential risk of malignancy, resulting in a large number of patients undergoing numerous imaging follow-up studies for many years. Therefore, there is a growing need for optimization of the current surveillance protocol to reduce both healthcare costs and waiting lists, while still maintaining appropriate sensibility and specificity. Imaging is an essential tool for evaluating patients with intraductal papillary mucinous neoplasms (IPMNs) since it can assess several predictors for malignancy and thus guide further management recommendations. Although contrast-enhanced magnetic resonance imaging (MRI) with magnetic resonance cholangiopancreatography (MRCP) has been widely recommended by most international guidelines, recent results support the use of unenhanced abbreviated-MRI (A-MRI) protocols as a surveillance tool in patients with IPMN. In fact, A-MRI has shown high diagnostic performance in malignant detection, with high sensitivity and specificity as well as excellent interobserver agreement. The aim of this paper is, therefore, to discuss the current available evidence on whether the implementation of an abbreviated-MRI (A-MRI) protocol for cystic pancreatic lesion surveillance could improve healthcare economics and reduce waiting lists in clinical practice without significantly reducing diagnostic accuracy. [ABSTRACT FROM AUTHOR]

Objectives In this paper, an artificial intelligence-based algorithm for predicting the optimal contrast medium dose for computed tomography (CT) angiography of the aorta is presented and evaluated in a clinical study. The prediction of the contrast dose reduction is modelled as a classification problem using the image contrast as the main feature. Methods This classification is performed by random decision forests (RDF) and k-nearest-neighbor methods (KNN). For the selection of optimal parameter subsets all possible combinations of the 22 clinical parameters (age, blood pressure, etc.) are considered using the classification accuracy and precision of the KNN classifier and RDF as quality criteria. Subsequently, the results of the evaluation were optimized by means of feature transformation using regression neural networks (RNN). These were used for a direct classification based on regressed Hounsfield units as well as preprocessing for a subsequent KNN classification. Results For feature selection, an RDF model achieved the highest accuracy of 84.42% and a KNN model achieved the best precision of 86.21%. The most important parameters include age, height, and hemoglobin. The feature transformation using an RNN considerably exceeded these values with an accuracy of 90.00% and a precision of 97.62% using all 22 parameters as input. However, also the feasibility of the parameter sets in routine clinical practice has to be considered, because some of the 22 parameters are not measured in routine clinical practice and additional measurement time of 15 to 20 minutes per patient is needed. Using the standard feature set available in clinical routine the best accuracy of 86.67% and precision of 93.18% was achieved by the RNN. Conclusion We developed a reliable hybrid system that helps radiologists determine the optimal contrast dose for CT angiography based on patient-specific parameters. [ABSTRACT FROM AUTHOR]

Jinhui Bu,1,2,&ast; Zhenfei Wang,2,&ast; Chao Ma,1,2 Juan Gao,2 Guangpu Liu,2 Libo Pang,2 Bo He,1 Minghui Dong,1 Quan Zhang,1 Yan Lei,1 Long Xu,2 Sen Huang,1 Yuming Li,3 Guangwang Liu1,2 1Xuzhou Clinical School of Xuzhou Medical University, Xuzhou, People’s Republic of China; 2Department of Orthopedic Surgery, Xuzhou Central Hospital, Xuzhou, People’s Republic of China; 3Department of Surgery, Boston Children’s Hospital, Harvard Medical School, Boston, MA, USA&ast;These authors contributed equally to this workCorrespondence: Yuming Li, Tel +1-8573524988, Fax +1-8572188459, Email yuming.li@childrens.harvard.edu; Guangwang Liu, Tel +86-18012018238, Fax +86-51683956400, Email guangwangliu@163.comObjective: To validate whether a residual mass demonstrated on early postoperative MR after percutaneous endoscopic lumbar discectomy (PELD) is indeed an intraoperatively retained annulus fibrosus, and explore the correlation between imaging changes in the residual mass and clinical prognosis of patients.Methods: A prospective study of 118 patients were included. During surgery, a contrast medium, Gadopentetate Dimeglumine, was injected around the ruptured annulus fibrosus. The intensity of the T2 signal, the size of the remaining mass (SR), and the cross-sectional area of the spinal canal (SCSA), VAS, and ODI were assessed at preoperative, 1-h (7-day), 6-month, and 12-month postoperative intervals. Based on VAS at 7 days post-surgery, patients were classified into either a non-remission group (Group A, VAS > 3) or a remission group (Group B, VAS ≤ 3).Results: Six patients who developed recurrent LDH were excluded. A residual mass was detected on MRI 1 h after surgery in 94.6% (106/112). During one year of follow-up, 90.1% (101/112) of the patients displayed fibrous annulus remodeling, although 68.7% (77/112) still exhibited herniation. Significant differences were found in the ODI between Groups A and B one week after surgery (p < 0.001). However, no significant differences were observed in T2 signal intensity, SR, and SCSA at 1-h, 6-month and 12-month post-surgery (p > 0.05) between the two groups. In a multiple linear regression analysis, early postoperative ODI changes were associated with T2 signal (B = − 10.22, sig < 0.05), long-term changes were associated with alterations in SR (B = 5.63, sig < 0.05) and SCSA (B = − 0.13, sig < 0.05).Conclusion: The residual mass observed in early postoperative MR images after PELD was the retained annulus fibrosus intraoperatively. Short-term changes in clinical symptoms after PELD were linked to T2 signal intensity, while long-term changes were associated with changes in SR and SCSA.Keywords: spinal endoscopy, residual mass, remodeling of fibrous annulus, contrast medium

Subtraction magnetic resonance imaging (MRI) has been reported to increase accuracy in the diagnosis of meningeal and inflammatory brain diseases in small animals. 3D T1W gradient recalled echo (GRE) techniques have been proposed as a suitable alternative to conventional spin echo sequences in imaging the canine brain. The aim of this study was to compare subtraction images and paired pre- and post-contrast 3D T1W GRE fat suppressed (FS) images in canine and feline MRI studies using clinical diagnosis as the gold standard. Paired preand post-contrast T1W 3D FS GRE images and individual subtraction images of 100 small animal patients were randomized and independently evaluated by 2 blinded observers. Diagnosis categories were "normal," "inflammatory," "neoplastic," and "other." Clinical diagnosis was made in the same categories and served as the gold standard. Image interpretation results were compared to the clinical diagnosis. Interobserver agreement was determined. Clinically, 41 studies were categorized as "normal," 18 as "inflammatory," 28 as "neoplastic," and 13 as "other." The agreement of the pre- and post-contrast GRE images with the gold standard was significantly higher than that of the subtraction images (k = 0.7491 vs. k = 0.5924; p = 0.0075). The largest sources of error were misinterpretation of "other" as "normal" and "normal" as "inflammatory." There was no significant difference between the two observers (p = 0.8820). Based on this study, subtraction images do not provide an advantage to paired pre- and post-contrast FS GRE images when evaluating the canine and feline brain. [ABSTRACT FROM AUTHOR]

This study aimed to compare the vascular enhancement and radiation dose in preoperative transcatheter aortic valve implantation (TAVI) computed tomography (CT) with a reduced contrast medium (CM) using volume scans in 256-multidetector row CT (MDCT) with a standard CM using 64-MDCT. This study included 78 patients with preoperative TAVI CT with either 64- or 256-MDCT. The CM was injected at 1.5 mL/kg in the 64-MDCT group and 1.0 mL/kg in the 256-MDCT group. We compared vascular enhancement of the aortic root and access routes, image quality (IQ) scores, and radiation dose in both groups. Despite the reduced CM (by 33 %) in the 256-MDCT group, the mean vascular enhancement of the right and left subclavian arteries was significantly higher than that in the 64-MDCT group [284 and 267 Hounsfield units (HU) vs. 376 and 359 HU; p < 0.05]; however, no significant differences in the mean vascular enhancement in the ascending aorta, abdominal aorta at the celiac level, and bilateral common femoral arteries were observed between the two groups (p > 0.05 for all). The median IQ scores at the aortic root were higher in the 256-MDCT group than in the 64-MDCT group (3 vs. 4; p < 0.05), and those at the femoral access routes were comparable (4 vs. 4; p = 0.33). The mean effective dose was significantly reduced by 30 % in the 256-MDCT group (23.6 vs. 16.3 mSv; p < 0.05). In preoperative TAVI CT, volume scans using 256-MDCT provide comparable or better vascular enhancement and IQ with a 30 % reduction in CM and radiation dose than those using 64-MDCT. Volume scan using 256-MDCT for preoperative TAVI CT may reduce CM and radiation dose in TAVI patients with renal dysfunction. [ABSTRACT FROM AUTHOR]

To compare CT (computed tomography) values for enhancement of the abdominal aorta and liver parenchyma during dynamic contrast enhancement (CE) CT in cirrhotic patients with and without splenomegaly (SM). We considered 258 patients (83 males and 46 females for the splenomegaly group, and 83 males and 46 females for the control group) for this retrospective study. We measured CT values in the abdominal aorta and hepatic parenchyma during the hepatic arterial (HAP) and portal venous (PVP) phases. The aortic CE at HAP and the hepatic parenchymal CE at PVP were compared between the two groups. For success rate of scans, we also calculated the optimal CE rates (>280 HU in the abdominal aorta and >50 HU in the hepatic parenchyma) for each group. In the SM group, the CE for abdominal aorta was decreased during the aortic phase for a dynamic CE-CT (p < 0.05). When evaluating the success rates, they were found to be 65.1 % and 58.9 % in the SM group and 81.4 % and 72.3 % in the non-SM group (p < 0.05). The success rate of scans and CE for the abdominal aorta during the aortic phase exhibited a significant decrease during dynamic CE-CT scans on patients with SM. Patients with SM may have reduced diagnostic ability with typical contrast injection protocols. It may be necessary to change the injection rates and contrast medium volume during CE-CT depending on the presence or absence of SM. [ABSTRACT FROM AUTHOR]

Introduction: This experimental study aimed to evaluate the efficacy of contrast medium-aided intraoral periapical radiographic imaging in the detection of cracked teeth and to determine optimal in-vitro compression force for crack detection. Methods: 27 extracted human lower premolar teeth were randomly divided into two groups: the control group, which was imaged using the conventional radiography and the experimental group which was imaged using a contrast medium (Iopamidol®). Both group were examined by transillumination to confirm the presence of a crack prior to imaging. A compression test using a Universal Testing Machine was used to induce the crack. Two dental clinicians blinded to the imaging technique evaluated the images and determined the presence or absence of cracks. Results: The force needed to produce a superficial crack ranges from 200N to 500N with a median compression force of 400N. The range of force to produce partial crack was 200N to 550N with the median force slightly higher than superficial crack which is 435N. The force to produce dentinal fracture ranges from 300N to 1100N with the highest median of 525N. The results showed that there were no visible cracks were detected in IOPA with/without contrast medium. Conclusions: The study did not find contrast-enhance IOPA to be effective in detecting cracks, but the study did establish the optimal median compression force values for inducing cracks which is between 400N to 525N. IOPA with contrast medium is not an effective diagnostic tool for cracked teeth compared to transillumination. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To determine the proximal diffusion distance of radiopaque contrast medium and mepivacaine/methylene blue solution and incidence of inadvertent intrasynovial and intravascular injections of modified sesamoid nerve block (MASB) when compared with traditional plantar nerve analgesia techniques of the equine distal hind limb. SAMPLE: Ex vivo model: 18 hind limbs; and in vivo model: 5 horses in a crossover study. METHODS: In the ex vivo model, a mepivacaine/methylene blue solution was used to compare the diffusion distance between MASB, basisesamoid block (BSB), and traditional low plantar block (TLPB). Ten minutes after injection, skin was dissected and proximal diffusion distance of the dye patch was measured. In the in vivo model, both hind limbs were injected with radiopaque contrast medium with either MASB or TLPB. Ten minutes after injection, a radiograph was acquired and the proximal diffusion of the contrast medium patch was measured. RESULTS: In the ex vivo model, solution proximal diffusion distance for MASB was significantly longer than BSB (P< .050) and significantly shorter than TLPB (P< .050). Both techniques reached the proximal aspect of DFTS similarly (P=.289), and no difference in the incidence of intrasynovial or intravascular injections was observed (P = .292). In the in vivo model, contrast medium proximal diffusion of MASB was significantly shorter than TLPB (P < .050). The proportion of injections that diffused subcutaneously to the proximal aspect of the proximal pouch of the DFTS was not significantly different between techniques (P = .136). No difference in the incidence of DFTS intrasynovial or intravascular injections was observed (P = .305). CLINICAL RELEVANCE: MASB presented significantly more proximal diffusion than BSB and less proximal diffusion than TLPB, consistently reached the proximal aspect of DFTS, and presented a very low risk of intrasynovial and intravascular injections. [ABSTRACT FROM AUTHOR]

Enhanced computed tomography (CT) is unsuitable for patients with reduced renal function and/or allergy for contrast medium (CM). CT image registration into an electroanatomic system (EAMS) is essential to perform pulmonary vein isolation (PVI) safely and smoothly in patients with atrial fibrillation (AF). To create three-dimensional pulmonary vein-left atrium (3D PV-LA) images from non-enhanced CT images to register them into EAMS for AF ablation. Using a non-enhanced ECG-gated image, 3D PV-LA images were generated by our developed techniques with an EnSite image analyzing tool for patients unfit for CM use (n = 100). Segmentation between tissues was performed as follows: tissues distal from or close to PV-LA were segmented in transverse slices to clearly show the whole LA. Tissues bordering PV-LA, including the pulmonary artery, left ventricle, and right atrium, were segmented manually with great care. Practical ablation parameters were compared with those obtained from enhanced CT (n = 100). 3D PV-LA image reconstruction from non-enhanced CT imaging required a longer time than that from enhanced CT (42 ± 6 vs 14 ± 3 min). All 100 PV-LA non-enhanced CT images were successfully reconstructed and registered into the EAM system without the need for re-segmentation. Practical ablation parameters, including procedural time and AF recurrence rate, did not differ between imaging methods. This study provides clinically useful information on a detailed methodology for 3D PV-LA image reconstruction using non-enhanced CT. Non-enhanced CT 3D PV-LA images were successfully registered into the EAM system and useful for patients unsuitable for CM use. [ABSTRACT FROM AUTHOR]

Subtraction magnetic resonance imaging (MRI) has been reported to increase accuracy in the diagnosis of meningeal and inflammatory brain diseases in small animals. 3D T1W gradient recalled echo (GRE) techniques have been proposed as a suitable alternative to conventional spin echo sequences in imaging the canine brain. The aim of this study was to compare subtraction images and paired pre- and post-contrast 3D T1W GRE fat suppressed (FS) images in canine and feline MRI studies using clinical diagnosis as the gold standard. Paired pre- and post-contrast T1W 3D FS GRE images and individual subtraction images of 100 small animal patients were randomized and independently evaluated by 2 blinded observers. Diagnosis categories were “normal,” “inflammatory,” “neoplastic,” and “other.” Clinical diagnosis was made in the same categories and served as the gold standard. Image interpretation results were compared to the clinical diagnosis. Interobserver agreement was determined. Clinically, 41 studies were categorized as “normal,” 18 as “inflammatory,” 28 as “neoplastic,” and 13 as “other.” The agreement of the pre- and post-contrast GRE images with the gold standard was significantly higher than that of the subtraction images (k = 0.7491 vs. k = 0.5924; p = 0.0075). The largest sources of error were misinterpretation of “other” as “normal” and “normal” as “inflammatory.” There was no significant difference between the two observers (p = 0.8820). Based on this study, subtraction images do not provide an advantage to paired pre- and post-contrast FS GRE images when evaluating the canine and feline brain.

Administration of fluid (oral and intravenous) is the cornerstone of prevention of contrast-associated acute kidney injury in the cardiac environment. Intravenous saline is the preferred fluid. The amount, timing, and duration of therapy are discussed. A key determinant of the benefit may be the rate of urine output stimulated by the therapy. Approaches using hemodynamic-guided rates of fluid administration and novel techniques to generate large urine outputs while maintaining fluid balance are highlighted. [ABSTRACT FROM AUTHOR]

Background: Contrast-associated acute kidney injury (CA-AKI) can develop after intravascular administration of iodinated contrast media. Neutrophil gelatinase-associated lipocalin (NGAL) is an early marker for AKI that helps to detect subclinical CA-AKI. We investigated the incidence of and risk factors for clinical and subclinical CA-AKI in patients who underwent neuroendovascular surgery. Methods: We retrospectively investigated 228 patients who underwent neuroendovascular surgery in 2020. Changes in serum creatinine and urine output were used to detect clinical CA-AKI. Urine NGAL concentration was used to detect subclinical CA-AKI in 67 out of 228 patients. Results: In 228 patients, serum creatinine, hemoglobin, hematocrit, total protein, and blood urea nitrogen (BUN) decreased significantly (p < 0.001) after surgery. However, serum creatinine decreased less significantly (p < 0.05) than hemoglobin, hematocrit, total protein, and BUN on postoperative Day 3. Two patients out of 228 developed clinical CA-AKI, and seven patients out of 67 with urine NGAL measurements developed subclinical CA-AKI. Multivariate regression analysis revealed that diabetes mellitus and carotid artery stenosis were significantly (p < 0.05) associated with the development of clinical and/or subclinical CA-AKI. Conclusion: There was a large difference between the incidences of clinical CA-AKI (0.88%) and subclinical CA-AKI (10.4%). The difference might have primarily resulted from the different sensitivities between serum creatinine and urine NGAL and possibly from underestimation of the incidence of clinical AKI due to a postoperative decrease in serum creatinine caused by hemodilution. In addition to diabetes mellitus, carotid artery stenosis could also be a risk factor for CA-AKI. [ABSTRACT FROM AUTHOR]

Objective: To determine the feasibility, safety, and outcomes of an oil-based, iodinated contrast using office-based, ultrasound-imaged hysterosalpingography in women with infertility. Design: Randomized Controlled Double Blind Clinical Trial. Setting: Academic health center. Intervention(s): Tubal flushing with oil-based contrast medium (Lipiodol UF) versus saline. Main Outcome Measure(s): Ongoing pregnancy rate, pain, quality of life, and thyroid function. Result(s): Forty-eight patients (24 in each group) were analyzed. The groups were well-matched at baseline. Ongoing pregnancy was noted in 17% (4/24) of the oil-contrast group versus 37% (9/24) in the saline group. Saline group patients more frequently initiated infertility therapy in the six-month follow-up period (saline, 67% vs. oil, 33%), and no serious adverse events in either group. There were no differences in pain from the procedure between groups. There were no differences in thyroid function tests postprocedure between groups, but within the oil-contrast group, there was a slight increase in thyroid-stimulating hormone (post vs. preratio of geometric means: 1.18; 95% confidence interval [CI], 1.02–1.38) and decrease in Free T4 (postdifference vs. predifference in means: 0.08 ng/dL; 95% CI, -0.14 to -0.01). Immediately after the test, the physicians correctly guessed 79% of oil and 71% of saline randomization assignments, whereas patients correctly guessed 63% of oil and 38% of saline. Conclusion(s): This pilot study demonstrates the safety and feasibility of giving an oil-based contrast medium during ultrasound-imaged hysterosalpingography. Pregnancies were seen after oil-based administration, and this contrast is associated with minor thyroid function impairment.

The incidence of vascular and especially aortic pathologies is increasing, which leads to a higher frequency of vascular imaging. As renal pathologies also become more frequent, especially in an aging population, the need for effective preventative scan protocols with reduced contrast material is pressing. An 81-year-old female patient in our institution required a follow-up imaging of an incidental, asymptomatic abdominal aortic aneurysm. Although the patient was suffering from incipient chronic renal failure, a contrast-enhanced aortoiliac computed tomography angiography was performed using a first generation, clinical photon-counting detector computed tomography scanner. This scanner allows a modified scan protocol with a significant reduction of contrast agent while preserving diagnostic confidence. Technically, this is feasible by dual-source spectral image acquisition and dynamic monochromatic reconstruction near the K-edge of Iodine without loss of temporal or spatial resolution. The results are promising, allowing vascular imaging with significantly less risk of renal damage. In this regard, further research into optimal scan-protocols and post-processing is needed.

Giant African land snails (GALS) have become increasingly popular, for example, as pets or in kindergartens in Europe, but little is known about their clinically relevant anatomy, diseases, or further details in diagnostic imaging. The present study focuses on the techniques and image interpretation of radiography, computed tomography, and sonography in GALS. The aim of the study is to find the most appropriate imaging tool to visualize the various organs within the mantle cavity (also known as visceral mass) in GALS. The detailed anatomy of GALS is presented with numerous figures of the different imaging techniques. The sensory organs and nervous system will not be part of the present study.

Background: J‐waves may be observed during coronary angiography (CAG) or intracoronary acetylcholine (ACh) administration, but their significance is unknown. Methods: Forty‐nine patients, 59.1 ± 11.5 years old and 59% male, were studied on suspicion of vasospastic angina, and J wave dynamicity was compared between CAG and Ach administration. Results: Diagnostic (≥0.1 mV) or nondiagnostic (<0.1 mV) J waves in 9 and 3 patients, respectively, were augmented, and J waves were newly observed in 2 patients during CAG and Ach administration. Similar changes in the J‐wave amplitude were observed: from 0.10 ± 0.09 mV to 0.20 ± 0.15 mV (p <.002) and from 0.10 ± 0.10 mV to 0.20 ± 0.16 mV (p <.001) during CAG and Ach administration, respectively. J waves were located in the inferior leads and changed only during the right coronary interventions. In the remaining 35 patients, J waves were absent before and during the coronary interventions. Augmentation of J waves was found when the RR interval was shortened in some patients. Injection of anoxic media into the coronary artery might induce a conduction delay from myocardial ischemia that manifests as augmentation or new occurrence of J waves. Conclusions: Both CAG and intracoronary Ach administration affected J waves similarly in the same individuals. A myocardial ischemia‐induced conduction delay may be responsible for the changes in J waves, but further studies are needed. [ABSTRACT FROM AUTHOR]

Ultrasound contrast agents have gained increasing popularity due to the high level of safety, real-time improved visualization, and ability to detect vascularity. As a result, contrast-enhanced ultrasound lends itself well to interventional radiology including in preprocedure assessment, intraprocedural guidance, and postprocedure evaluation. The authors aim to demonstrate the wide utility of contrast-enhanced ultrasound in both vascular and nonvascular intervention.

ObjectivesThe use of near infrared transillumination for caries detection is gaining recognition in daily practice. Differentiation between cavitated and non cavitated proximal lesions is recognized as a threshold for restorative treatment. This investigation focused on the use of a near infrared absorbent dye which may enhance the detection of cavitation on near infrared transillumination images.Materials and methods1: Natural teeth with artificial proximal cavitation were images with 3 different dyes to establish that near infrared absorbent dye can act like a contrast medium. 2: Natural teeth with natural cavitated lesions were used to investigate the contrast enhancing effect of indocyanine green (ICG) on near infrared transillumination images. 3: Artificial teeth with artificial cavitations were used to determine the best consistency of ICG as a contrast medium. 4: natural teeth with proximal lesions were used to confirm that ICG can differentiate between cavitated and non cavitated proximal lesions.Results1: ICG enhanced the contrast of cavitations compared to other dyes (ANOVA; p  0.05). 3: ICG in a gel form enhanced the detection of cavitated lesions when compared to liquid ICG (t-test; p

Abstract Background Atherosclerosis is a common cardiovascular disease in parrots but the antemortem diagnosis is challenging. In human medicine, computed tomography angiography (CTA) has been used widely for the diagnosis of atherosclerosis. By adjusting the injection rate and total dose of contrast medium, the image quality can be improved. To test the effects of different injection conditions on the image quality of major arteries, 10 African grey parrots (Psittacus erithacus) were used. Three injection rates (0.3, 0.4, 0.5 mL/s) and three doses (740, 370, 222 mg of iodine/bird) were tested while the other variables of the studies were fixed. Result A higher injection dose led to a significantly higher attenuation, image noise and diameter, with a lower signal-to-noise ratio and contrast-to-noise ratio of the six major arteries. The 370 mg of iodine/bird group showed significantly better subjective image quality. Furthermore, with increasing injection rates, the prevalence of heterogeneity decreased. However, we found an increased risk of injection failure for the 0.5 mL/s groups. Conclusion We recommend a combination of 370 mg of iodine/bird with 0.4 mL/s for clinical use to achieve better image quality for CTA.

Background Serum creatinine (SCr) is unreliable in detecting acute changes in kidney function. Early recognition of contrast-induced acute kidney injury (CI-AKI) can provide better opportunities for preventive interventions. Therefore, the purpose of this study is to examine the value of the combined detection of urinary neutrophil gelatinase-associated lipocalin (NGAL), insulin-like growth factor binding protein-7 (IGFBP-7), and tissue inhibitor of metalloproteinase-2 (TIMP-2) in the early diagnosis of children with CI-AKI.Methods A prospective, single-center clinical trial was performed and included 172 children aged 0–18 years. The dynamic changes of urinary NGAL, IGFBP-7, and TIMP-2 levels in children with intravascular injection of contrast medium were investigated to determine whether they can diagnose CI-AKI early.Results CI-AKI occurred in 20 of 137 enrolled patients, and the incidence was 14.59%. In the CI-AKI group, urinary levels of NGAL, IGFBP-7, TIMP-2, and [IGFBP-7]*[TIMP-2] were significantly increased 2 h after angiography and remained at high levels at 6 h. Using a cutoff value of 36.274 ng/mL, the specificity was 70.0%, and the sensitivity was 68.4% for the prediction of CI-AKI, which was excellent for urinary NGAL. When both urinary IGFBP-7 and TIMP-2 were used together, urinary [IGFBP-7]*[TIMP-2] at 0.417(ng/mL)2/1000 was regarded as the cutoff value. The specificity was 80.0%, and the sensitivity was 81.2%.Conclusions NGAL, IGFBP-7, and TIMP-2 concentrations in the urine of children after receiving injections of contrast medium increased faster than SCr and had good clinical value for the early diagnosis of CI-AKI in children. The combination of IGFBP-7 and TIMP-2 was better than either analyte alone.

Computed tomography (CT) is used in veterinary medicine for the diagnosis of bones and soft tissue diseases in various species. In addition, CT has recently been used to diagnose aquatic animals, including Selachimorpha, which are difficult to diagnose out of water. However, because Selachimorpha do not have adipose tissue in the coelomic cavity, the coelomic organs cannot be fully identified using non‐contrast CT (NCCT). The aim of this study is to present the anatomical features of the cadaver, NCCT, and contrast‐enhanced CT (CECT) as well as the change in CT values of the coelomic organs and musculature of the brownbanded bamboo shark. NCCT scans were performed under anaesthesia in one male and one female shark. CECT was performed 30 min after iopamidol was administered intravenously. The sharks were euthanized, frozen at −20°C, and sliced in the same position in which they were scanned. Using electric band saw, 10‐mm transversal sections were obtained. The anatomical structures of both males and females were identified by transversal sections, and CT images homologous to transversal sections were then selected. Sagittal and coronal CECT images were also obtained to facilitate understanding of the location and size of coelomic organs. Although bone structure and air in organs could be sufficiently discriminated on NCCT image, the coelomic organs were almost indistinguishable. On the other hand, CECT images obtained sufficient contrast to identify most coelomic organs in addition to bone and air. The results provide an atlas of a cross‐sectional anatomy and CECT images, which is useful information for the medical diagnosis of coelomic organs in live Selachimorpha. [ABSTRACT FROM AUTHOR]

Contrast-enhanced medical imaging is commonly requested in clinical practice. Contrast media provide better differentiation of tissue enhancement, improves the soft tissue contrast resolution, and enhances the ability to study the physiology and function of the organs and/or systems. However, contrast media may cause complications, especially in patients with renal failure. This article discusses the use of contrast media in common imaging modalities and the relationship between contrast media and renal function. Administration of iodinated contrast media in computed tomography may cause contrast-associated acute kidney injury; the risk factors and preventive strategies for this are elaborated in this article. Administration of gadolinium-based contrast media in magnetic resonance imaging may lead to nephrogenic systemic fibrosis. Therefore, precautions should be taken when planning for medical imaging for patients with pre-existing acute kidney injury or end-stage chronic kidney disease, for whom contrast media administration in computed tomography or magnetic resonance imaging may be relatively contraindicated. Alternatively, ultrasound contrast agents can be safely used in patients with acute kidney injury or chronic kidney disease. Clinical teams should discuss these patients with radiologists, taking into account the risk–benefits of contrast media, to determine the optimal imaging protocol or modality to answer the clinical query. [ABSTRACT FROM AUTHOR]

Aim: During percutaneous coronary intervention (PCI), complicated lesions in the target coronary artery often hinder device delivery. Fluid lubricants have commonly been used to reduce friction between adjacent solid materials in manufacturing, thus achieving smoother action. This ex vivo experimental study examined whether a contrast medium could function as a fluid lubricant during PCI. Methods and results: We used two different coronary artery lesion models with distinct complexities made from silicon. Each model was fit into the ex vivo PCI-simulation system. This ex vivo laboratory equipment consisted of ordinary PCI instruments and an aorta model from the Valsalva sinus to the descending aorta. A Wolverine™ cutting balloon catheter was advanced through each lesion model via a guide catheter set into the system. The maximum force required to push the catheter through the lesion models was measured while the vessel system was filled with either normal saline or contrast medium. The maximum force required was significantly lower with the contrast medium (1.38 ± 0.21 N in the normal-saline condition vs. 0.92 ± 0.05 N in the contrast-medium condition in the lesion model A, p

Yan Lin,1,2,&ast; Gaofeng Zhu,3,&ast; Xiaoyong Li,4,&ast; Huaxiao Yu,5 Yuhang Luo,5 Jiaqiong Lin,6 Renyuan Li,7 Zena Huang2 1Department of Nephrology, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, People’s Republic of China; 2Yunkang School of Medicine and Health, Nanfang College, Guangzhou, People’s Republic of China; 3Department of General Medicine, Guangdong Provincial People’s Hospital, Guangdong Academy of Medical Sciences, Guangzhou, People’s Republic of China; 4Department of General Surgery, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, People’s Republic of China; 5The Third Clinical School, Guangzhou Medical University, Guangzhou, People’s Republic of China; 6Affiliated Dongguan Maternal and Child Healthcare Hospital, Southern Medical University, Guangzhou, People’s Republic of China; 7Department of Endocrinology and Metabolism, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, People’s Republic of China&ast;These authors contributed equally to this workCorrespondence: Zena Huang, Yunkang School of Medicine and Health, Nanfang College, Guangzhou, People’s Republic of China, Tel +86-13570466614, Email huangzn@nfu.edu.cn Renyuan Li, Department of Endocrinology and Metabolism, The Third Affiliated Hospital of Guangzhou Medical University, Guangzhou, People’s Republic of China, Tel +86-18926146852, Email lirenyuan@gzhmu.edu.cnBackground: Icariin presents protective effect in several kidney diseases. However, the role of icariin in contrast-induced acute kidney injury (CIAKI) is still unclear. This study aimed to investigate the effect of icariin in CIAKI, as well as exploring the underlying mechanism from the aspect of interaction between protein-coding genes and non-coding RNAs.Methods: The effect of icariin was evaluated in both in vivo and in vitro CIAKI models. Rat kidneys were collected for genome-wide sequencing. The differentially expressed genes (DEGs) were screened and visualized by R software. The function annotation of DEGs was analyzed by Metascape. By Cytoscape software, the competing endogenous RNA (ceRNA) network was constructed, and hub genes were selected. Expressions of hub genes were validated by PCR. Association of hub genes in the ceRNA network and renal function was also examined.Results: Icariin protected against CIAKI in both in vivo and in vitro models. Based on DEGs in icariin pretreated CIAKI rats, lncRNA- and circRNA-associated ceRNA networks were constructed, respectively. Function annotation showed the ceRNA networks were enriched in ERK1 and ERK2 cascade, MAPK signaling and NF-κB signaling. Further, two circRNAs, six lncRNAs, four miRNAs and nine mRNAs were selected as hub genes of the ceRNA network. Among them, eight mRNAs (Acot1, Cbwd1, Ly6i, Map3k14, Mettl2b, Nyap1, Set and Utp20) were negatively correlated with renal function, while one mRNA (Tmem44) was positively correlated with renal function.Conclusion: Icariin presented a protective effect against CIAKI. The ceRNA network, involving Acot1, Cbwd1, Ly6i, Map3k14, Mettl2, Nyap1, Set, Tmem44 and Utp20, might partially contribute to the underlying mechanism of icariin protection by regulation of ERK1 and ERK2 cascade, MAPK signaling and NF-κB signaling.Keywords: icariin, contrast medium, acute kidney injury, competing endogenous RNA, non-coding RNA

We investigated the effect of T2* on each lipid proton through a phantom experiment by the effect of contrast medium concentration on magnetic resonance spectroscopy PRESS (Point Resolved Spectroscopy) and STEAM (Stimulated Echo Acquisition Mode) pulse sequence. We produced a virtual fatty liver phantom with 10% fat deposited, under the assumption that the contrast medium was absorbed at two concentrations in the liver. The main feature of this phantom is that the fat content of the two types of phantoms is the same, but the concentration of the contrast medium is (0.3 and 5) mM, respectively. Data of the phantom were acquired using a 9.4 T high magnetic field MRI/S inspection device, and at this time, MRS was acquired with a 4-ch receive coil for data reception. The MRS signal of each lipid proton (LP) according to the TE change was measured using the STEAM and PRESS pulse sequences, and the spin–spin relaxation was calculated for the measured lipid proton signal through spin–spin relaxation curve fitting. The fat percentage in STEAM and PRESS calculated as the sum of M0 of the 7 lipid protons was (10.7 and 18.8) %, respectively, on 0.3 mM contrast medium fatty liver phantom. The accurate fat quantification is possible through spin–spin relaxation correction by acquiring data using the STEAM pulse sequence. The STEAM pulse sequence has the advantage of being able to accurately quantify each LP, because the j–j coupling effect between the lipid protons is small, but has the characteristic that the signal is measured two-to-three times lower than that of the PRESS pulse sequence. In an intrahepatic environment with a high contrast agent concentration, fat percentage error estimation occurs due to the T2* phenomenon, so MRS should be obtained before administration of the contrast agent. The PRESS pulse sequence data provide information suitable for clinical follow-up, or to evaluate the increase or decrease of fat deposition with high signal measurement, because the fat percentage is overestimated, due to the effect of J–J coupling, even when spin–spin correction is performed. [ABSTRACT FROM AUTHOR]

Objectives: To further reduce the contrast medium (CM) dose of full aortic CT angiography (ACTA) imaging using the augmented cycle-consistent adversarial framework (Au-CycleGAN) algorithm. Methods: We prospectively enrolled 150 consecutive patients with suspected aortic disease. All received ACTA scans of ultra-low-dose CM (ULDCM) protocol and low-dose CM (LDCM) protocol. These data were randomly assigned to the training datasets (n = 100) and the validation datasets (n = 50). The ULDCM images were reconstructed by the Au-CycleGAN algorithm. Then, the AI-based ULDCM images were compared with LDCM images in terms of image quality and diagnostic accuracy. Results: The mean image quality score of each location in the AI-based ULDCM group was higher than that in the ULDCM group but a little lower than that in the LDCM group (all p < 0.05). All AI-based ULDCM images met the diagnostic requirements (score ≥ 3). Except for the image noise, the AI-based ULDCM images had higher attenuation value than the ULDCM and LDCM images as well as higher SNR and CNR in all locations of the aorta analyzed (all p < 0.05). Similar results were also seen in obese patients (BMI > 25, all p < 0.05). Using the findings of LDCM images as the reference, the AI-based ULDCM images showed good diagnostic parameters and no significant differences in any of the analyzed aortic disease diagnoses (all K-values > 0.80, p < 0.05). Conclusions: The required dose of CM for full ACTA imaging can be reduced to one-third of the CM dose of the LDCM protocol while maintaining image quality and diagnostic accuracy using the Au-CycleGAN algorithm. Key Points: • The required dose of contrast medium (CM) for full ACTA imaging can be reduced to one-third of the CM dose of the low-dose contrast medium (LDCM) protocol using the Au-CycleGAN algorithm. • Except for the image noise, the AI-based ultra-low-dose contrast medium (ULDCM) images had better quantitative image quality parameters than the ULDCM and LDCM images. • No significant diagnostic differences were noted between the AI-based ULDCM and LDCM images regarding all the analyzed aortic disease diagnoses. [ABSTRACT FROM AUTHOR]

Ultrasound contrast agents have gained increasing popularity due to the high level of safety, real-time improved visualization, and ability to detect vascularity. As a result, contrast-enhanced ultrasound lends itself well to interventional radiology including in preprocedure assessment, intraprocedural guidance, and postprocedure evaluation. The authors aim to demonstrate the wide utility of contrast-enhanced ultrasound in both vascular and nonvascular intervention. [ABSTRACT FROM AUTHOR]

Background: Atherosclerosis is a common cardiovascular disease in parrots but the antemortem diagnosis is challenging. In human medicine, computed tomography angiography (CTA) has been used widely for the diagnosis of atherosclerosis. By adjusting the injection rate and total dose of contrast medium, the image quality can be improved. To test the effects of different injection conditions on the image quality of major arteries, 10 African grey parrots (Psittacus erithacus) were used. Three injection rates (0.3, 0.4, 0.5 mL/s) and three doses (740, 370, 222 mg of iodine/bird) were tested while the other variables of the studies were fixed. Result: A higher injection dose led to a significantly higher attenuation, image noise and diameter, with a lower signal-to-noise ratio and contrast-to-noise ratio of the six major arteries. The 370 mg of iodine/bird group showed significantly better subjective image quality. Furthermore, with increasing injection rates, the prevalence of heterogeneity decreased. However, we found an increased risk of injection failure for the 0.5 mL/s groups. Conclusion: We recommend a combination of 370 mg of iodine/bird with 0.4 mL/s for clinical use to achieve better image quality for CTA. [ABSTRACT FROM AUTHOR]

Serum creatinine (SCr) is unreliable in detecting acute changes in kidney function. Early recognition of contrast-induced acute kidney injury (CI-AKI) can provide better opportunities for preventive interventions. Therefore, the purpose of this study is to examine the value of the combined detection of urinary neutrophil gelatinase-associated lipocalin (NGAL), insulin-like growth factor binding protein-7 (IGFBP-7), and tissue inhibitor of metalloproteinase-2 (TIMP-2) in the early diagnosis of children with CI-AKI. A prospective, single-center clinical trial was performed and included 172 children aged 0–18 years. The dynamic changes of urinary NGAL, IGFBP-7, and TIMP-2 levels in children with intravascular injection of contrast medium were investigated to determine whether they can diagnose CI-AKI early. CI-AKI occurred in 20 of 137 enrolled patients, and the incidence was 14.59%. In the CI-AKI group, urinary levels of NGAL, IGFBP-7, TIMP-2, and [IGFBP-7]*[TIMP-2] were significantly increased 2 h after angiography and remained at high levels at 6 h. Using a cutoff value of 36.274 ng/mL, the specificity was 70.0%, and the sensitivity was 68.4% for the prediction of CI-AKI, which was excellent for urinary NGAL. When both urinary IGFBP-7 and TIMP-2 were used together, urinary [IGFBP-7]*[TIMP-2] at 0.417(ng/mL)2/1000 was regarded as the cutoff value. The specificity was 80.0%, and the sensitivity was 81.2%. NGAL, IGFBP-7, and TIMP-2 concentrations in the urine of children after receiving injections of contrast medium increased faster than SCr and had good clinical value for the early diagnosis of CI-AKI in children. The combination of IGFBP-7 and TIMP-2 was better than either analyte alone. [ABSTRACT FROM AUTHOR]

Purpose: Despite improved techniques and sophisticated postinterventional care, symptomatic intracranial hemorrhage (sICH) remains the most feared complication of mechanical thrombectomy (MT). Based on peri-interventional parameters, we aimed to discover which patients have a higher risk of sICH. Methods: From March 2017 until March 2020 consecutive patients with acute ischemic stroke (AIS) and confirmed large-vessel occlusion who underwent MT were analyzed retrospectively. Demographic, clinical, and radiological variables and parameters specific to thrombectomy were reviewed. A univariate analysis was performed and statistically significant variables were included in a logistic regression model to identify independent factors predictive of sICH. Results: A total of 236 patients with confirmed large-vessel occlusion were included and 22 (9.3%) had sICH. Univariate predictors of sICH included diabetes mellitus, glucose > 11.1 mmol/L, creatinine clearance (CrCl) ≤ 30 ml/min/1.73, ASPECTS indicating pretreatment infarct size, acute internal carotid artery (ICA) occlusion, stent implantation, tirofiban use, time from symptom onset to groin puncture > 4.5 h and high contrast medium consumption. In the adjusted analysis, ASPECTS < 6 (OR 3.673, p = 0.041), and amount of contrast injected ≥ 140 ml (OR 5.412, p = 0.003) were independent predictors of sICH, but not any more baseline glucose > 11.1 mmol/L (OR 1.467, p = 0.584), CrCl ≤ 30 ml/min/1.73 (OR 4.177, p = 0.069), acute ICA occlusion (OR 2.079, p = 0.181), stent implantation (OR 0.465, p = 0.512), tirofiban use (OR 5.164, p = 0.167), and time from onset-to-groin puncture (OR 1.453, p = 0.514). Conclusion: The amount of contrast medium used is a modifiable factor associated with sICH. This association is novel and may be related to the neurotoxicity of the contrast medium disrupting the blood-brain barrier. [ABSTRACT FROM AUTHOR]

Coronary Roadmap (CR), a modern imaging software, provides real-time information for decision-making during coronary interventions. However, whether CR also reduces the required volume of contrast medium and radiation dose remains uncertain. In this study, the volume of contrast medium and radiation exposure for both patients and operators in the CR-guided interventions were compared with those in the conventional group. In this single center and case control study, 124 patients receiving percutaneous coronary interventions were retrospectively studied and divided into the conventional and CR-guided coronary intervention group. The contrast medium volume used, Dose-Area Product (DAP), and corresponding skin doses of the patients as well as the radiation exposures of the operators were recorded and compared. SPSS. Despite no significant differences between age and underlying comorbidities, there were significantly lower DAP and skin doses in patients receiving CR-guided interventions compared with those receiving conventional ones. Moreover, the volume of contrast medium was significantly reduced in the CR group. Regarding the radiation exposure for the operators, there was a significantly lower exposure in the CR-guided group than in the conventional group. The CR-guided interventions may significantly reduce the required volume of contrast medium and radiation exposure compared with conventional interventions. More comprehensive applications of the CR-guided intervention is suggested for clinical use. • The CR-guided imaging significantly reduces contrast volume for the PCI procedure. • The CR-guided PCI markedly decreases radiation dose of patients and operators. • Time needed for the PCI procedure is apparently decreased by the CR-guided intervention. • No increased adverse events were found in the CR-guided PCI. [ABSTRACT FROM AUTHOR]

Qingqing Li, Shengqi Pan Department of Intensive Care Medicine, Qingdao Municipal Hospital, Qingdao, People’s Republic of ChinaCorrespondence: Qingqing Li, Department of Intensive Care Medicine, Qingdao Municipal Hospital, Qingdao, People’s Republic of China, Email 2276105001@qq.comAbstract: A decrease in renal function that follows intravascular administration of contrast medium (CM) within a few days is reported as contrast-induced acute kidney injury (CI-AKI). In clinical practice, the imaging procedure is frequently deferred when clinicians consider that the renal risks caused by CM outweigh the benefits of enhanced imaging. However, with an in-depth understanding of AKI and contrast medium, scholars have realized that the decrease in renal function after CM is caused by contrast medium factors and noncontrast medium factors (such as anemia and hemodynamic instability). Therefore, acute kidney injury caused by CM has been overestimated in the past. The term “contrast-associated acute kidney injury (CA-AKI)” has been increasingly used to indicate AKI after intravascular administration of contrast medium compared with CI-AKI. CA-AKI can increase the risk of death and chronic kidney disease. However, its pathophysiological mechanism has not been fully elucidated, and the effectiveness of various preventive and therapeutic measures have been questioned. These present challenges for us. In this article, we will review the diagnostic criteria, epidemiology, risk factors, pathophysiological mechanisms and treatment of CA-AKI to provide optimized imaging procedures in clinical practice.Keywords: contrast-associated acute kidney injury, contrast medium, acute kidney injury

Abstract Background Kidney infarction is a renovascular disease diagnosed by contrast‐enhanced computed tomography (CECT) in humans. Objectives To describe the frequency of kidney infarction and to determine the detection of kidney infarction with CECT in dogs. Animals Eight hundred and twenty‐six abdominal CECT studies of 826 dogs. Methods A cross‐sectional retrospective study. Dogs with abdominal CT scans including CECT were retrospectively retrieved. Kidney infarction was classified into 3 grades based on the extent of infarction relative to total kidney area. The location and number of kidney infarctions in each kidney were expressed as number and percentage. The ability of visualization of kidney infarction in each multiplanar reconstruction (MPR) image plane was evaluated by agreement of 2 observers. Results The frequency of kidney infarction in dogs was 3.15% (26/826 dogs; 95% CI = 2.05‐4.61). Most kidney infarctions were classified as grade 1, or the lesions were less than 25% of the kidney (47/56, 83.93%) and most were detected at the caudal pole of the kidney (31/56, 55.35%) on the sagittal plane. On MPR image planes, the sagittal plane had the highest proportion (34/56, 60.71%) of excellent visual category to detect kidney infarction. Conclusions and Clinical Importance The CECT, especially the sagittal plane, is a useful diagnostic tool for the detection of kidney infarction in dogs.