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Objective: The study aimed to investigate the effects of the level of contraction during isometric shoulder abduction at different abduction angles on muscle thickness and stiffness of the shoulder girdle in asymptomatic individuals. Design: Measurement properties study. Setting: Biomechanics and motion analysis lab. Participants: Twenty individuals volunteered to participate in this study. Main Outcome Measure: The subjects were tested for morphological and mechanical properties, expressed by thickness and stiffness of the supraspinatus tendon and muscle, and upper trapezius muscle. Moreover, acromiohumeral distance was also evaluated using B-mode ultrasound and shear-wave elastography. Intervention: The thickness and stiffness of the supraspinatus and upper trapezius muscle were assessed at 3 angles of abduction (0°, 60°, and 90°) and 3 levels of contraction (0%, 10%, and 20% of the maximal voluntary isometric contraction) using ultrasonography with shear-wave imaging. Moreover, the acromiohumeral distance was measured to establish the occupation ratio during passive movement. Results: The supraspinatus and upper trapezius muscle thickness and stiffness were significantly greater at 60° shoulder abduction compared with 0°, and 90° compared with 60°, as well as significantly greater at 20% maximal voluntary isometric contraction compared with 0% and 10% maximal voluntary isometric contraction. Thickness and stiffness were significantly greater in the supraspinatus compared with the upper trapezius muscle at all 3 angles of shoulder abduction for all 3 level of contractions. The acromiohumeral distance decreased significantly from 0° to 60° and from 60° to 90°. Conclusion: Morphological and mechanical properties of the supraspinatus and upper trapezius muscles depended on the relative level of muscle contraction and the angle of shoulder abduction. [ABSTRACT FROM AUTHOR]

Following anterior cruciate ligament reconstruction (ACLR), patients exhibit abnormal walking mechanics and quadriceps dysfunction. Quadriceps dysfunction has been largely attributed to muscle atrophy and weakness. While important, these factors do not capture intrinsic properties of muscle that govern its ability to generate force and withstand load. While fascicle abnormalities after ACLR have been documented in early stages of recovery (<12 mo), long-term effects of ACLR on fascicle mechanics remain unexplored. We evaluated quadriceps fascicle mechanics during walking 3 years post-ACLR and examined the relationship with knee mechanics. Participants included 24 individuals with ACLR and 24 Controls. Linear mixed models compared the ACLR, Contralateral, and Controls limbs for (1) quadriceps strength, (2) fascicle architecture and mechanics, and (3) knee mechanics. No difference in strength or overall fascicle length excursions was found between limbs. The ACLR limb exhibited longer fascicles at heel strike and peak knee extension moment (P <.001–.004), and smaller fascicle angles at heel strike, peak knee extension moment, and overall suppressed fascicle angle excursions (P <.001–.049) relative to the Contralateral and/or Control limb. This indicates an abnormality in fascicle architecture and mechanics following ACLR and suggests abnormalities in contractile function that cannot be explained by muscle weakness and may contribute to long-term gait irregularities. [ABSTRACT FROM AUTHOR]

Introduction: Carpal tunnel syndrome is an entrapment neuropathy that affects 3% of adults in the United States. The current techniques used for diagnosis have limited specificity/sensitivity, and the techniques used for treatment have limited efficacy.Case Report: A 34-year-old female presented to the emergency department with two months of worsening painful paresthesias in her right thenar eminence. Ultrasound was performed showing a median nerve area of 20.4 square millimeters within the carpal tunnel. Median nerve block was performed within the carpal tunnel causing complete resolution of her pain.Conclusion: Emergency physicians skilled in point-of-care ultrasound and needle-guided procedures can diagnose and treat carpel tunnel syndrome.

INTRODUCTION: Brace treatment is common to address radiological dysplasia in infants with developmental dysplasia of the hip (DDH); however, it is unclear whether bracing provides significant benefit above careful observation by ultrasound. If observation alone is non-inferior to bracing for radiological dysplasia, unnecessary treatment may be avoided. Therefore, the purpose of this study is to determine whether observation is non-inferior to bracing for infants with radiological dysplasia. METHODS AND ANALYSIS: This will be a multicentre, global, randomised, non-inferiority trial performed under the auspices of a global prospective registry for infants and children diagnosed with DDH. Patients will be included if they present with radiological dysplasia (centred hip, alpha angle 43-60°, percent femoral head coverage greater than 35% measured on ultrasound) of a clinically stable hip under 3 months old. Patients will be excluded if they present with clinical hip instability, have received prior treatment or have known/suspected neuromuscular, collagen, chromosomal or lower-extremity congenital abnormalities or syndromic-associated hip abnormalities. Patients will be enrolled and randomised to undergo observation alone or brace treatment with a Pavlik harness for a minimum of 6 weeks. Follow-up visits will occur at 6 weeks, 1 year and 2 years post-enrolment. The primary outcome will be the norm-referenced acetabular index measured on the 2-year radiograph with a 3° non-inferiority margin. A total of 514 patients will be included.The study is anticipated to start in April 2024 and end in September 2028.The primary outcome will be compared between arms with a mixed-effects model with a random intercept for study centre, and a single covariate for the treatment group. If the lower bound of the 95% CI lies within 3° of the mean, we will treat this as evidence for non-inferiority. ETHICS AND DISSEMINATION: Ethics approval has been obtained from the lead sites ethics board (University of British Columbia, Childrens and Womens Research Ethics Board). Ethics approval will be obtained from the local ethics committees or institutional review boards at each institution prior to patient enrolment. It is intended that the results of this study shall be published in peer-reviewed journals and presented at suitable conferences. TRIAL REGISTRATION NUMBER: NCT05869851.

Introduction: Compressive neuropathy of the brachial plexus is a common issue following laparoscopic and robotic surgeries.Case Report: A 71-year-old male, post-lumbar spinal surgery, presented with excruciating right upper extremity pain and paresthesias. A supraclavicular brachial plexus (SBP) block with bupivacaine provided significant pain relief, lasting 36 hours. Subsequent physical therapy led to gradual pain and weakness improvement in compressive neuropathy.Discussion: The SBP block, facilitated by ultrasound guidance, is a safe procedure with few serious complications. It proves beneficial for managing postoperative compressive neuropathy, allowing patients to break pain cycles and participate in rehabilitation.Conclusion: The SBP block is an effective addition to the management of postoperative compressive neuropathy, given its ease, safety, and potency. Although regional anesthesia provides only temporary relief, patients can experience a break in debilitating pain cycles associated with compressive neuropathy.

Case Presentation: A 60-year-old female presented to the emergency department with unilateral eye pain and vision loss. Point-of-care ultrasound (POCUS) was performed, which demonstrated ocular metastatic lesions of breast cancer.Discussion: Ocular metastasis is rare, clinically challenging, and may present with a wide range of ophthalmic symptoms. However, POCUS may safely and rapidly identify metastatic lesions to direct further care.

Introduction: Peritonsillar abscesses form between the tonsillar capsule, the superior constrictor, and palatopharyngeus muscles. Physicians traditionally make this diagnosis clinically; however, ultrasound allows clinicians to further identify and differentiate between peritonsillitis, peritonsillar abscess, and phlegmon formation. By increasing both the sensitivity and specificity, ultrasound improves the diagnostic accuracy for patients with peritonsillar abscesses. This case demonstrates the utilization of ultrasound in peritonsillar abscesses and the application of point-of-care ultrasound (POCUS) in identifying complications of procedures used for treatment in the emergency department (ED).Case Report: A 19-year-old male presented to the ED with complaints of severe sore throat and fever for the prior five days. A POCUS using an endocavitary probe with sterile cover demonstrated hypoechoic debris with a “swirl sign.” Ultrasound was used to successfully guide needle aspiration by using in-plane needle guidance. The patient had significant bleeding after needle aspiration, and repeat POCUS clearly identified a new pocket of blood that had formed and was contained in the soft tissue. We monitored the size of the hematoma in real time with ultrasound to ensure the hematoma had no rapid expansion and was stable.Conclusion: Among the differential diagnoses for sore throat, the diagnosis of peritonsillar abscess is particularly concerning as it is both common and generally requires swift intervention. Presentations can range from a mild infection to a life-threatening emergency with potential airway compromise. The two primary avenues for treatment include either needle aspiration or incision and drainage. Ultrasound can successfully identify the abscess and other landmarks for safe and successful drainage, as well as early identification of complications.

Introduction: Rectus abdominis muscle strains are common and can be debilitating in both professional and amateur athletes who engage in strenuous activity.Case Report: We report a rare case of rectus abdominis muscle tear in an amateur bodybuilder diagnosed by point-of-care ultrasound (POCUS) in the emergency department (ED). The patient had presented to the ED three separate times after strenuous exercise, received costly diagnostic workups, and ultimately was diagnosed on the third visit with grade 2 bilateral rectus abdominis tear. The patient was given appropriate education and sports medicine follow-up. He underwent rehabilitation focused on trunk and core stability. At eight-week follow-up, the patient had made a full recovery.Conclusion: To our knowledge, a case of bilateral rectus abdominis tear diagnosed by ultrasound in the emergency setting has not been previously published. Our case report highlights the utility of POCUS in diagnosing musculoskeletal pathology and preventing costly bounce-back visits.

Introduction: Point-of-care ultrasound (POCUS) performed by emergency physicians (EP) has emerged as an effective alternative to radiology department ultrasounds for the diagnosis of lower extremity deep vein thrombosis (DVT). Systematic reviews suggested good sensitivity and specificity overall for EP-performed POCUS for DVT diagnosis, yet high levels of heterogeneity were reported.Methods: In this systematic review and meta-analysis, we aimed to provide the most up-to-date estimates of the accuracy of EP-performed POCUS for diagnosis of DVT and to explore potential correlations with test performance. We performed systematic searches in MEDLINE and Embase for original, primary data articles from January 2012–June 2021 comparing the efficacy of POCUS performed by EPs to the local standard. Quality Assessment of Diagnostic Accuracy Studies-2 for individual articles are reported. We obtained summary measures of sensitivity, specificity, and their corresponding 95% confidence intervals (CI) using bivariate mixed-effects regression models. We performed meta-regression, subgroup, and sensitivity analyses as planned in the protocol CRD42021268799 submitted to PROSPERO.Results: Fifteen publications fit the inclusion criteria, totaling 2,511 examinations. Pooled sensitivity and specificity were 90% (95% CI 82%–95%) and 95% (CI 91%–97%), respectively. Subgroup analyses by EP experience found significantly better accuracy for exams performed by EP specialists (93%, CI 88%–97%) vs trainees (77%, CI 60%–94%). Specificity for EP specialists (97%, CI 94%–99%) was higher than for trainees (87%, CI 76%–99%, P = 0.01). Three-point compression ultrasound (CUS) was more sensitive than two-point CUS but was only statistically significant when limited to EP specialists (92% vs 88%, P = 0.07, and 95% vs 88%, P = 0.02, respectively).Conclusion: Point-of-care ultrasound performed by emergency physicians is sensitive and specific for the diagnosis of suspected DVT when performed by trained attending EPs. Three-point compression ultrasound examination may be more sensitive than two-point CUS.

OBJECTIVES: The Salivary Gland Committee of the American Academy of Otolaryngology-Head and Neck Surgery seeks to standardize terminology and technique for ultrasonograpy used in the evaluation and treatment of salivary gland disorders. METHODS: Development of expert opinion obtained through interaction with international practitioners representing multiple specialties. This committee work includes a comprehensive literature review with presentation of case examples to propose a standardized protocol for the language used in ultrasound salivary gland assessment. RESULTS: A multiple segment proposal is initiated with this focus on the submandibular gland. We provide a concise rationale for recommended descriptive language highlighted by a more extensive supplement that includes an extensive literature review with additional case examples. CONCLUSION: Recommendations are provided to improve consistency both in performing and reporting submandibular gland ultrasound.

Handheld ultrasound devices can be used in revision rhinoplasty to evaluate the calcification of costal rib cartilage that is to be harvested for grafting. This article provides instructions on how to perform this technique. Laryngoscope, 134:651-653, 2024.

This work presents a continuous volumetric indoor air temperature measurement scheme using PMUTs (piezoelectric micromachined ultrasonic transducers). Advancements as compared to state-of-art works include: (1) 'volumetric' temperature monitoring instead traditional 'pointwise' temperature information; (2) accurate temperature readings spanning an operational distance of 5 m as validated by a commercial thermometer for 3 days; and (3) capable of detecting global average temperature and local temperature events by installing networked/grid PMUT pairs. This innovative sensing technique could be applicable for the precision control of future building/living environments.

Introduction: Sternoclavicular joint (SCJ) septic arthritis is a rare but rapidly fatal joint infection. Without proper medical or surgical management, it can progress to osteomyelitis, chest wall abscess, mediastinitis, or myositis.Case Report: A 57-year-old male with a past history of intravenous drug use presented to the emergency department (ED) with chest tenderness of one week duration. Vital signs were unremarkable, and exam was notable for tender, raised right SCJ without any fluctuance. On point-of-care ultrasound we noted fluid collection and capsular distention along the SCJ, which aided in rapidly diagnosing septic arthritis. The patient was immediately started on antibiotics and taken to the operating room for excision and debridement.Conclusion: While computed tomography is routinely used in the emergency department for diagnosing septic arthritis, ultrasound offers a rapid and safe alternative for diagnosis.

Introduction: Carpal tunnel syndrome (CTS) is a common complaint in the emergency department (ED) and accounts for approximately 90% of all peripheral neuropathies.6 Pain control from injection with corticosteroids into the carpal tunnel space is associated with multiple possible complications including atrophy, iatrogenic median nerve injury, and skin changes. Ultrasound (US)-guided mid-forearm median nerve block is an ED procedure that can be used to avoid direct injection into the carpal tunnel space. Here we present a case report proposing the use of US-guided mid-forearm block as a safe and effective adjunct to the management of acute pain caused by CTS.Case Report: A previously healthy 44-year-old, right-hand dominant female presented to the ED with left wrist pain. Her clinical exam and US findings were consistent with CTS. Given her allergy to non-steroidal anti-inflammatory drugs, she was offered a median nerve block, which was performed in the ED. The patient reported continued pain relief 24 hours after discharge from the ED.Conclusion: There is limited data on the use of US-guided mid-forearm median nerve block as an acute pain management tool for CTS in the ED. The US-guided median nerve block done in the mid-forearm location can provide pain control for those with CTS while reducing the risk of complications associated with direct carpal tunnel injection.

Intussusception is a familiar diagnosis among the pediatric population; however, it is rarely consideredamong the adult population due to a myriad of life-threatening pathologies within the abdomen. We presentan adult female who presented to the emergency department (ED) with abdominal pain and constipation.Laboratory testing and a computed tomography (CT) scan of the abdomen were ordered. Laboratory testresults were notable for an elevated lymphocyte count as well as leukocyte esterase, white blood cells (WBC),and bacteria seen on urinalysis. The computed tomography scan detected a colo-colic intussusceptionsecondary to a benign mass within the bowel lumen. The mass was surgically resected and the patient hadan uneventful postoperative course. This unique case represents the occurrence of a pathology to which theadult population is not immune, and therefore should not be overlooked when evaluating a non-specific caseof abdominal pain.

Most ultrasound-based processes root in empirical approaches. Because nearly all advances have been conducted in aqueous systems, there exists a paucity of information on sonoprocessing in other solvents, particularly ionic liquids (ILs). In this work, we modelled an ultrasonic horn-type sonoreactor and investigated the effects of ultrasound power, sonotrode immersion depth, and solvents thermodynamic properties on acoustic cavitation in nine imidazolium-based and three pyrrolidinium-based ILs. The model accounts for bubbles, acoustic impedance mismatch at interfaces, and treats the ILs as incompressible, Newtonian, and saturated with argon. Following a statistical analysis of the simulation results, we determined that viscosity and ultrasound input power are the most significant variables affecting the intensity of the acoustic pressure field (P), the volume of cavitation zones (V), and the magnitude of the maximum acoustic streaming surface velocity (u). V and u increase with the increase of ultrasound input power and the decrease in viscosity, whereas the magnitude of negative P decreases as ultrasound power and viscosity increase. Probe immersion depth positively correlates with V, but its impact on P and u is insignificant. 1-alkyl-3-methylimidazolium-based ILs yielded the largest V and the fastest acoustic jets - 0.77 cm3 and 24.4 m s-1 for 1-ethyl-3-methylimidazolium chloride at 60 W. 1-methyl-3-(3-sulfopropyl)-imidazolium-based ILs generated the smallest V and lowest u - 0.17 cm3 and 1.7 m s-1 for 1-methyl-3-(3-sulfopropyl)-imidazolium p-toluene sulfonate at 20 W. Sonochemiluminescence experiments validated the model.

Purpose To assess adherence to the US Liver Imaging Reporting and Data System (LI-RADS) recommendations for hepatocellular carcinoma (HCC) surveillance and associated patient-level factors in a vulnerable, diverse patient sample. Materials and Methods The radiology report database was queried retrospectively for patients who underwent US LI-RADS-based surveillance examinations at a single institution between June 1, 2020, and February 28, 2021. Initial US and follow-up liver imaging were included. Sociodemographic and clinical data were captured from electronic medical records. Adherence to radiologist recommendation was defined as imaging (US, CT, or MRI) follow-up in 5-7 months for US-1, imaging follow-up in 3-6 months for US-2, and CT or MRI follow-up in 2 months for US-3. Descriptive analysis and multivariable modeling that adjusted for age, sex, race, and time since COVID-19 pandemic onset were performed. Results Among 936 patients, the mean age was 59.1 years; 531 patients (56.7%) were male and 544 (58.1%) were Asian or Pacific Islander, 91 (9.7%) were Black, 129 (13.8%) were Hispanic, 147 (15.7%) were White, and 25 (2.7%) self-reported as other race. The overall adherence rate was 38.8% (95% CI: 35.7, 41.9). The most common liver disease etiology was hepatitis B (60.6% [657 of 936 patients]); 19.7% of patients (183 of 936) had current or past substance use disorder, and 44.8% (416 of 936) smoked. At adjusted multivariable analysis, older age (odds ratio [OR], 1.20; P = .02), male sex (OR, 1.62; P = .003), hepatology clinic attendance (OR, 3.81; P < .001), and recent prior US examination (OR, 2.44; P < .001) were associated with full adherence, while current smoking (OR, 0.39; P < .001) was negatively associated. Conclusion Adherence to HCC imaging surveillance was suboptimal, despite US LI-RADS implementation. Keywords: Liver, Ultrasound, Screening, Abdomen/GI, Cirrhosis, Metabolic Disorders, Socioeconomic Issues Supplemental material is available for this article. © RSNA, 2024.

Introduction: Identification of patients not meeting catheterization laboratory activation criteria by electrocardiogram (ECG) but who would benefit from early coronary intervention remains challenging in the emergency department (ED). The purpose of this study was to evaluate whether emergency physician (EP)-performed point-of-care transthoracic echocardiography (POC TTE) could help identify patients who required coronary intervention within this population.Methods: This was a retrospective observational cohort study of adult patients who presented to two EDs between 2018–2020. Patients were included if they received a POC TTE and underwent diagnostic coronary angiography within 72 hours of ED presentation. We excluded patients meeting catheterization laboratory activation criteria on initial ED ECG. Ultrasound studies were independently reviewed for presence of regional wall motion abnormalities (RWMA) by two blinded ultrasound fellowship-trained EPs. We then calculated test characteristics for coronary intervention.Results: Of the 221 patient encounters meeting inclusion criteria, 104 (47%) received coronary intervention or coronary artery bypass grafting (CABG) referral. Overall prevalence of RWMA on POC TTE was 35% (95% confidence interval [CI] 29–42%). Presence of RWMA had 38% (95% CI 29–49%) sensitivity and 68% (95% CI 58–76%) specificity for coronary intervention/CABG referral. Presence of “new” RWMA (presence on EP-performed POC TTE and prior normal echocardiogram) had 43% (95%CI 10–82%) sensitivity and 93% (95% CI 66–100%) specificity for coronary intervention/CABG referral. The EP-performed POC TTE interpretation of RWMA had 57% (95% CI 47–67%) sensitivity and 96%(95% CI 87–100%) specificity for presence of RWMA on subsequent cardiology echocardiogram during the same admission.Conclusion: Presence of RWMA on EP-performed POC TTE had limited sensitivity or specificity for coronary intervention or referral to CABG. The observed specificity appeared to trend higher in subjects with a prior echocardiogram demonstrating absence of RWMA, although a larger sample size will be required to confirm this finding. The EP-performed POC TTE RWMA had high specificity for presence of RWMA on subsequent cardiology echocardiogram. Further evaluation of the diagnostic performance of new RWMA on EP-performed POC TTE with a dedicated cohort is warranted.

ABSTRACT Objective Methods Results Conclusion Performing obstetric ultrasound scans is challenging for inexperienced operators; therefore, the prenatal screening artificial intelligence system (PSAIS) software was developed to provide real‐time feedback and guidance for trainees during their scanning procedures. The aim of this study was to investigate the potential benefits of utilizing such an artificial intelligence system to enhance the efficiency of obstetric ultrasound training in acquiring and interpreting standard basic views.A prospective, single‐center randomized controlled study was conducted at The First Affiliated Hospital of Sun Yat‐sen University. From September 2022 to April 2023, residents with no prior obstetric ultrasound experience were recruited and assigned randomly to either a PSAIS‐assisted training group or a conventional training group. Each trainee underwent a four‐cycle practical scan training program, performing 20 scans in each cycle on pregnant volunteers at 18–32 gestational weeks, focusing on acquiring and interpreting standard basic views. At the end of each cycle, a test scan evaluated trainees' ability to obtain standard ultrasound views without PSAIS assistance, and image quality was rated by both the trainees themselves and an expert (in a blinded manner). The primary outcome was the number of training cycles required for each trainee to meet a certain standard of proficiency (i.e. end‐of‐cycle test scored by the expert at ≥ 80%). Secondary outcomes included the expert ratings of the image quality in each trainee's end‐of‐cycle test and the discordance between ratings by trainees and the expert.In total, 32 residents and 1809 pregnant women (2720 scans) were recruited for the study. The PSAIS‐assisted trainee group required significantly fewer training cycles compared with the non‐PSAIS‐assisted group to meet quality requirements (P = 0.037). Based on the expert ratings of image quality, the PSAIS‐assisted training group exhibited superior ability in acquiring standard imaging views compared with the conventional training group in the third (P = 0.012) and fourth (P < 0.001) cycles. In both groups, the discordance between trainees' ratings of the quality of their own images and the expert's ratings decreased with increasing training time. A statistically significant difference in overall trainee–expert rating discordance between the two groups emerged at the end of the first training cycle and remained at every cycle thereafter (P < 0.013).By assisting inexperienced trainees in obtaining and interpreting standard basic obstetric scanning views, the use of artificial intelligence‐assisted systems has the potential to improve training effectiveness. © 2024 International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

Purpose: This study aimed to investigate the relationship between physical activity (PA) levels and short-term changes in skeletal muscle characteristics in patients with subacute hemiparetic stroke. Materials and Methods: This prospective observational study included 76 patients with stroke who received inpatient care in a convalescent rehabilitation ward. The PA level was measured as the duration of daily total PA (≥ 1.5 metabolic equivalents) using a triaxial accelerometer for 7 days after admission. The outcomes were changes in the quadriceps muscle quality and quantity on the affected and unaffected sides, as assessed by ultrasonography at admission and 1 month after admission. Results: Multiple regression analysis indicated that the duration of total PA was significantly associated with a percentage change in quadriceps muscle quality (p = 0.011) and quantity (p = 0.012) on the affected side. However, no significant relationship was observed between the muscle quality and quantity on the unaffected side. Conclusions: The results revealed that PA was associated with changes in the quadriceps muscle quality and quantity on the affected side in patients with subacute hemiparetic stroke. These findings highlight the importance of promoting PA in stroke rehabilitation to improve muscle properties and functional outcomes. IMPLICATIONS FOR REHABILITATION: Improving skeletal muscle quality and quantity is an important goal in post-stroke rehabilitation. We investigated physical activity and post-stroke changes in muscle properties. Physical activity is related to changes in muscle quantity and quality on the affected side. Promoting physical activity is essential for improving muscle quantity and quality on the affected side. [ABSTRACT FROM AUTHOR]

Fetal age in Quarter Horses can be predicted within 2 weeks from 100- to 200- days of gestation using femur length, biparietal diameter (cranium diameter) and eye approximated volume. However, as pregnancy advances, the femur and cranium become too large to be imaged in their entirety using ultrasound and the corresponding biometric parameters can no longer be measured. In this longitudinal study, the proximal phalanx (P1) was evaluated as a novel biometric parameter for late gestation to predict fetal age and bone maturation. Transrectal ultrasound was performed in ten pregnant mares with known ovulation dates, every two weeks from 240- days of gestation until parturition. P1 was imaged in 69 % of the examinations. Inability to image P1 was due to obstructive positioning such as carpal or fetlock flexion, or posterior presentation of the fetus. Advancing fetal age did not affect visibility of P1. P1 length correlated significantly with days of gestation and a correlation equation was established: y = 0.3837x -69.55 where y is the predicted value of P1 length and x is the day of gestation (with day 0 being the day of ovulation). When P1 length was equal to or larger than the width of the ultrasound image (52.5 mm), 90 % of mares (9/10) were above 300- days of gestation. Ossification of the proximal and distal epiphysis of P1 typically appeared between 277- and 303 -days of gestation (mean: 288 days). The proximal epiphysis did not close before parturition whereas the distal one closed between 306- and 333-days of gestation (mean: 320 days). P1 epiphyseal appearance and closure occurred chronologically reflecting bone maturation. Radiographic findings at birth and prenatal ultrasound findings were in agreement, apart from timing of P1 distal epiphyseal closure. In conclusion, P1 length can be used as a new fetal biometric parameter to assess fetal age and growth after 240- days of gestation. The knowledge of P1 bone maturation process in utero as a marker for fetal bone development, may also be valuable in clinical decision-making when considering inducing parturition in the mare. [ABSTRACT FROM AUTHOR]

Background: Data-driven digital learning could improve the diagnostic performance of novice students for thyroid nodules. Objective: To evaluate the efficacy of digital self-learning and artificial intelligence-based computer-assisted diagnosis (AI-CAD) for inexperienced readers to diagnose thyroid nodules. Methods: Between February and August 2023, a total of 26 readers (less than 1 year of experience in thyroid US from various departments) from 6 hospitals participated in this study. Readers completed an online learning session comprising 3,000 thyroid nodules annotated as benign or malignant independently. They were asked to assess a test set consisting of 120 thyroid nodules with known surgical pathology before and after a learning session. Then, they referred to AI-CAD and made their final decisions on the thyroid nodules. Diagnostic performances before and after self-training and with AI-CAD assistance were evaluated and compared between radiology residents and readers from different specialties. Results: AUC (area under the receiver operating characteristic curve) improved after the self-learning session, and it improved further after radiologists referred to AI-CAD (0.679 vs 0.713 vs 0.758, p<0.05). Although the 18 radiology residents showed improved AUC (0.7 to 0.743, p=0.016) and accuracy (69.9% to 74.2%, p=0.013) after self-learning, the readers from other departments did not. With AI-CAD assistance, sensitivity (radiology 70.3% to 74.9%, others 67.9% to 82.3%, all p<0.05) and accuracy (radiology 74.2% to 77.1%, others 64.4% to 72.8%, all p <0.05) improved in all readers. Conclusion: While AI-CAD assistance helps improve the diagnostic performance of all inexperienced readers for thyroid nodules, self-learning was only effective for radiology residents with more background knowledge of ultrasonography. [ABSTRACT FROM AUTHOR]