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To study the association of MRCP+ parameters with biochemical scoring systems and MR elastography (MRE) in primary sclerosing cholangitis (PSC). To evaluate the incremental value of combining MRCP+ with morphological scores in associating with biochemical scores. MRI images, liver stiffness measurements by MRE, and biochemical testing of 65 patients with PSC that were retrospectively enrolled between January 2014 and December 2015 were obtained. MRCP+ was used to post-process MRCP images to obtain quantitative measurements of the bile ducts and biliary tree. Linear regression analysis was used to test the associations. Bootstrapping was used as a validation method. The total number of segmental strictures had the strongest association with Mayo Risk Score (R2 = 0.14), minimum stricture diameter had the highest association with Amsterdam Oxford Prognostic Index (R2 = 0.12), and the percentage of duct nodes with width 0–3 mm had the strongest association with PSC Risk Estimate Tool (R2 = 0.09). The presence of Ducts with medians > 9 mm had the highest association with MRE (R2= 0.21). The strength of association of MRCP+ to Mayo Risk Score was similar to ANALI2 and weaker than MRE (R2 = 0.23, 0.24, 0.38 respectively). MRCP+ enhanced the association of ANALI 2 and MRE with the Mayo Risk Score. MRCP+ demonstrated a significant association with biochemical scores and MRE. The association of MRCP+ with the biochemical scores was generally comparable to ANALI scores. MRCP+ enhanced the association of ANALI2 and MRE with the Mayo Risk Score. • MRCP+ has the potential to act as a risk stratfier in PSC. • MRE outperformed MRCP+ for risk stratifcation. • Combination of MRCP+ with MRE and ANALI scores improved overall performace as risk stratifiers.

Objective During the COVID-19 pandemic, there was a temporary cessation of mammography screening. However, in some facilities, diagnostic breast imaging services continued for patients with a high clinical suspicion of breast cancer. The objective of this study was to evaluate changes in the diagnostic interval (DI) of non-screening patients presenting for diagnostic mammography during the first wave of the COVID-19 pandemic. Methods Retrospective chart review was performed on patients presenting for non-screening diagnostic mammography from April 1 to June 30, 2020 (pandemic group) and April 1 to June 30, 2019 (pre-pandemic group). Age, reason for referral, number and type of imaging studies/biopsies necessary for a final diagnosis were recorded. Diagnostic interval (DI) was defined as the number of days from the date of the diagnostic mammogram to the date of the final diagnosis. Results Compared to the pre-pandemic group (n = 64), the pandemic group (n = 77) showed a reduction in DI of the entire cohort (pandemic: 1 day; pre-pandemic: 15 days, p < 0.0001) for patients not requiring tissue sampling (pandemic: 1 day; pre-pandemic: 11 days, .p < 0.0001) and those requiring tissue sampling with benign pathology (pandemic 9 days; pre-pandemic, 33 days, p = 0.0002). A higher percentage of patients in the pandemic group had their assessment completed during the initial visit (pandemic: 50.6%; pre-pandemic: 23.4%, p = 0.0009). Conclusion During the first wave of the COVID-19 pandemic, the DI for patients with non-screening-related diagnostic mammography was significantly shorter, with a higher percentage of patients completing their assessments on the initial visit, compared to one year prior. Key Points • Despite reductions in manpower and clinical services, during pandemic times, it is possible to maintain a diagnostic breast imaging service for women at high clinical suspicion for breast cancer. • During pandemic times, breast imaging departments should consider restructuring to a Rapid Diagnostic Unit model with a navigation team that follows patients through the assessment process to a final diagnosis. • Departmental restructuring and patient navigation during pandemic times could either maintain or shorten the diagnostic interval for patients presenting for diagnostic mammography.

To compare biliary stricture severity on magnetic resonance cholangiopancreatography (MRCP), magnetic resonance elastography (MRE), and vibration-controlled transient elastography (VCTE) liver stiffness (LS) for evaluation of risk stratification and prognostication in primary sclerosing cholangitis (PSC). Eighty-seven patients (31–61 years; 34 female/53 male) prospectively underwent biochemical testing, VCTE, MRCP, and MRE between January 2014 and July 2016. Correlation between the MRCP grading of PSC based on biliary stricture severity, LS on MRE and VCTE, and the Mayo Risk Score as well as the Amsterdam Oxford Prognostic Index (AOPI) were evaluated and compared. Stricture severity was classified according to previous classification systems based on ERCP. Spearman’s correlation and Kruskal-Wallis tests were performed. MRE-LS and intrahepatic stricture severity combined demonstrated higher discriminatory ability among risk categories based on Mayo Risk Score (AUROC = 0.8). MRE-LS alone demonstrated excellent discriminatory ability among risk categories based on AOPI using cutoffs of 1 and 2.7 and was superior to intrahepatic stricture severity (AUROC = 0.9, AUROC = 0.6–0.7). There was a weak correlation between intrahepatic stricture severity and MRE-LS (rho = 0.3; p = 0.011). VCTE-LS values were not correlated with stricture severity and were noncontributory to differentiate patients across risk groups. Intrahepatic stricture severity alone was a poor discriminator of advanced liver fibrosis on MRE (AUROC = 0.7); however, combining intra- and extrahepatic stricture severity and controlling for cholestasis and disease duration improved results (AUROC = 0.9). This study demonstrates a significant discriminatory ability of LS values on MRE to distinguish between early to moderate and advanced liver fibrosis. LS values on MRE may add value to risk prognostication and further studies including clinical outcomes are needed. • Risk stratification was excellent for liver stiffness measurements on MRE and poor for VCTE and biliary stricture severity. • Risk stratification was further improved when liver stiffness measured on MRE was combined with intrahepatic and extrahepatic stricture severity and indicators of cholestasis were controlled for. • Liver stiffness measurements on MRE correlated with prognostic scores better than measurements performed on VCTE.

Fractures of the cervical spine are a medical emergency and may lead to permanent paralysis and even death. Accurate diagnosis in patients with suspected fractures by computed tomography (CT) is critical to patient management. In this paper, we propose a deep convolutional neural network (DCNN) with a bidirectional long-short term memory (BLSTM) layer for the automated detection of cervical spine fractures in CT axial images. We used an annotated dataset of 3,666 CT scans (729 positive and 2,937 negative cases) to train and validate the model. The validation results show a classification accuracy of 70.92% and 79.18% on the balanced (104 positive and 104 negative cases) and imbalanced (104 positive and 419 negative cases) test datasets, respectively., This paper is accepted for presentation at the IEEE International Symposium on Biomedical Imaging (ISBI) 2021

The objective of this article is to review the normal anatomy and posttraumatic findings of the Chopart joint complex. Key imaging features of the normal ligaments and patterns of ligamentous and osseous injuries are discussed.Traumatic midtarsal injuries, particularly midtarsal sprain, are often overlooked clinically and on imaging but are relatively common and typically are associated with inversion ankle injuries. Radiologists should be familiar with Chopart joint anatomy and the imaging features of midtarsal injuries because early diagnosis may help optimize clinical management.

The shoulder joint is the most unstable articulation in the entire human body. While this certainly introduces vulnerability to injury, it also confers the advantage of broad range of motion. There are many elements that work in combination to offset the inherent instability of the glenohumeral joint, but the glenoid labrum is perhaps related most often. Broadly, clinical unidirectional instability can be subdivided into anterior and posterior instability, which usually raise concern for anteroinferior and posteroinferior labral lesions, respectively. In the special case of superior labral damage, potential dislocation is blocked by structures that include the acromion; hence, while damage elsewhere commonly manifests as clinical instability, damage to the superior labrum is often described by the term microinstability. In this particular case, one of the radiologist's main concerns should be classic superior labral anteroposterior lesions. The glenoid labrum is also subject to a wide range of normal variants that can mimic labral tears. Knowledge of these variants is central to interpreting an imaging study of the labrum because misdiagnosis of labral variants as tears can lead to superfluous surgical procedures and decreased shoulder mobility. This article reviews labral anatomy and normal labral variants, describes their imaging features, and discusses how to discriminate normal variants from labral tears. Specific labral pathologic lesions are described per labral quadrant (anteroinferior, posteroinferior, and superior), and imaging features are described in detail. Online supplemental material is available for this article. ©RSNA, 2016.

The ankle is one of the most common sites of musculoskeletal injury. In a series of 1176 athletic injuries, 14% were found to be injuries of the ankle, and 85% of those were specifically sprains of ankle ligaments [1]. Although many ankle ligaments can be well assessed by an operator trained in ultrasound techniques, evaluation by magnetic resonance imaging (MRI) offers the advantages of a comprehensive and operator-independent examination [2]. In this article, a practical review of MRI of ankle ligaments is presented. The discussion is limited primarily to the ligaments surrounding the tibiotalar joint, particularly the inferior tibiofibular syndesmotic ligaments and the medial and lateral collateral ligaments (Table 1). Because of its close association with the deltoid ligament, the spring ligament is also included. Ligament names are represented by unambiguous abbreviations similar to those appearing in the literature [3e5]. For each ligament, normal anatomy, MRI appearance, and function will be addressed. Next, with regards to the injured ligament, basic mechanisms of injury will be reviewed, taking into consideration differing opinions in the literature that, in some cases, diverge from the classic teachings of Lauge and Hansen [3]. Because ligament injury usually manifests itself in similar ways, such as abnormal signal intensity (intrasubstance or periligamentous) or abnormal morphology (thickening, thinning, discontinuity, absence, irregularity, indistinctness, or heterotopic ossification) [2,4,6], additional imaging clues to injury that are ligamentspecific will be emphasized. Finally, because chronic injury

The glenohumeral joint has a wide range of motion which can be advantageous in activities such as overhead throwing sports or occupational activities that require a wide variety of movements in the shoulder. However, this wide range of motion makes it an unstable joint and this is the major reason why shoulder instability and shoulder dislocation are very frequent in traumatic injuries such as falls and sports-related injuries. It is important to be familiar with the normal anatomical and pathologic imaging appearances of the structures in the shoulder to effectively diagnose and treat glenohumeral instability injuries. This chapter provides an up-to-date review of the normal shoulder anatomy and the various clinical and imaging features involved in glenohumeral instability with an emphasis on the MRI manifestations.

The midtarsal (Chopart) joint complex consists of the talonavicular and calcaneocuboid joints and their stabilizing ligaments. Detailed assessment of this complex at MRI can be challenging owing to frequent anatomic variation and the small size of the structures involved. Nevertheless, a wide spectrum of pathologic conditions affect the joint complex, and its imaging evaluation deserves more thorough consideration. This review focuses on MRI evaluation of normal ligamentous anatomy and common variations about the Chopart joint, presenting practical imaging tips and potential diagnostic pitfalls. Imaging findings across a spectrum of traumatic Chopart joint injuries are also reviewed, from midtarsal sprains to Chopart fracture-dislocations. Midtarsal sprains-commonly associated with ankle inversion injuries-are emphasized, along with their often predictable radiographic and MRI injury patterns. Online DICOM image stacks are available for this article. ©RSNA, 2018.

Magnetic resonance imaging (MRI) represents the preferred noninvasive imaging technique to diagnose meniscal pathology in the pre- and postoperative setting. Furthermore, characterization of meniscal tissue MR properties has been possible by the development of advanced MRI techniques. Suspected meniscal tears are a frequent indication for MRI and the International Society of Arthroscopy, Knee Surgery and Orthopaedic Sports Medicine (ISAKOS) classification system has been developed to facilitate accurate and uniform reporting of such meniscal tears. Partial meniscectomy and meniscal suture repair are among the commonly performed procedures and several signs have been described to detect postoperative recurrent tears on MRI. Other techniques that have proven useful for meniscal assessment are ultrasound (US) and computed tomography (CT) arthrography. In recent years, US is being increasingly used in the selective assessment of some meniscal pathology such as tears, parameniscal cysts and meniscal extrusion as it is a relatively inexpensive, accessible, and safe technique. CT arthrography has been advocated as an acceptable alternative in patients with contraindications for MRI, with comparable diagnostic performance.

To determine the feasibility of using MR microscopy to characterize the root ligaments of the human knee at both ultra-high-field (11.7 T) and high-field (3 T) strengths. Seven fresh cadaveric knees were used for this study. Six specimens were imaged at 11.7 T and one specimen at 3 T using isotropic or near-isotropic voxels. Histologic correlation was performed on the posteromedial root ligament of one specimen. Meniscal root ligament shape, signal intensity, and ultrastructure were characterized. High-resolution, high-contrast volumetric images were generated from both MR systems. Meniscal root ligaments were predominantly oval in shape. Increased signal intensity was most evident at the posteromedial and posterolateral root ligaments. On the specimen that underwent histologic preparation, increased signal intensity corresponded to regions of enthesis fibrocartilage. Collagen fascicles were continuous between the menisci and root ligaments. Predominantly horizontal meniscal radial tie fibers continued into the root ligaments as vertical endoligaments. MR microscopy can be used to characterize and delineate the distinct ultrastructure of the root ligaments on both ultra-high-field- and high-field-strength MR systems.

Following a brief description of the normal anatomy and biomechanics of the midfoot, this article focuses on MR imaging features of common osseous, tendon, and ligament abnormalities that affect the midfoot. Discussion of the anatomy and pathology affecting the Chopart and Lisfranc joint complexes, both of which play important roles in linking the midfoot to the hindfoot and the forefoot respectively, is also included.

Ankle impingement syndromes encompass a broad spectrum of post-traumatic and chronic degenerative changes that present with pain on specific movements about the ankle joint. Both amateur and professional athletes are disproportionately affected by these conditions, and while conservative measures can potentially treat an impingement syndrome, definitive therapy is often alleviated surgically. Imaging (including conventional radiography, ultrasound, CT and MRI) plays an invaluable role in the diagnosis and pre-surgical work-up. An anatomically based classification system is useful in these syndromes, as the aetiology, sites of pathology and preferred treatment methods are similarly based on anatomic locations about the ankle. This review focuses on the anatomic locations, pathophysiology, imaging considerations and brief discussion of therapies for each of the major anatomic ankle impingement syndromes.

Author(s): Iwasaki, Kenyu; Tafur, Monica; Chang, Eric Y; Statum, Sheronda; Biswas, Reni; Tran, Betty; Bae, Won C; Du, Jiang; Bydder, Graeme M; Chung, Christine B | Abstract: ObjectiveThis study aimed to implement qualitative and quantitative magnetic resonance sequences for the evaluation of labral pathology.MethodsSix glenoid labra were dissected, and the anterior and posterior portions were divided into normal, mildly degenerated, or severely degenerated groups using gross and magnetic resonance findings. Qualitative evaluation was performed using T1-weighted, proton density-weighted, spoiled gradient echo and ultrashort echo time (UTE) sequences. Quantitative evaluation included T2 and T1rho measurements as well as T1, T2*, and T1rho measurements acquired with UTE techniques.ResultsSpoiled gradient echo and UTE sequences best demonstrated labral fiber structure. Degenerated labra had a tendency toward decreased T1 values, increased T2/T2* values, and increased T1rho values. T2* values obtained with the UTE sequence allowed for delineation among normal, mildly degenerated, and severely degenerated groups (P l 0.001).ConclusionsQuantitative T2* measurements acquired with the UTE technique are useful for distinguishing among normal, mildly degenerated, and severely degenerated labra.

To implement high-resolution morphologic and quantitative magnetic resonance imaging (MRI) of the temporomandibular joint (TMJ) using ultrashort time-to-echo (UTE) techniques in cadavers and volunteers. This study was approved by the institutional review board. TMJs of cadavers and volunteers were imaged on a 3-T MR system. High-resolution morphologic and quantitative sequences using conventional and UTE techniques were performed in cadaveric TMJs. Morphologic and UTE quantitative sequences were performed in asymptomatic and symptomatic volunteers. Morphologic evaluation demonstrated the TMJ structures in open- and closed-mouth position. UTE techniques facilitated the visualization of the disc and fibrocartilage. Quantitative UTE MRI was successfully performed ex vivo and in vivo, reflecting the degree of degeneration. There was a difference in the mean UTE T2* values between asymptomatic and symptomatic volunteers. MRI evaluation of the TMJ using UTE techniques allows characterization of the internal structure and quantification of the MR properties of the disc. Quantitative UTE MRI can be performed in vivo with short scan times.

The purposes of this study were to determine the prevalence of altered MRI appearances of "posterior medial meniscus root ligament (PMMRL)" lesions, introduce a classification of lesion types, and report associated findings.We retrospectively reviewed 419 knee MRI studies to identify the presence of PMMRL lesions. Classification was established on the basis of lesions encountered. The medial compartment was assessed for medial meniscal tears in the meniscus proper, medial meniscal extrusion, insertional PMMRL osseous changes, regional synovitis, osteoarthritis, insufficiency fracture, and cruciate ligament abnormality.PMMRL abnormalities occurred in 28.6% (120/419) of the studies: degeneration, 14.3% (60/419) and tear, 14.3% (60/419). Our classification system included degeneration and tearing. Tearing was categorized as partial or complete with delineation of the point of failure as entheseal, midsubstance, or junction to meniscus. Of all tears, 93.3% (56/60) occurred at the meniscal junction. Univariate analysis revealed significant differences between the knees with and without PMMRL lesions in age, medial meniscal tear, medial meniscal extrusion, insertional PMMRL osseous change, regional synovitis, osteoarthritis, insufficiency fracture (p=0.017), and cruciate ligament degeneration (p0.001).PMMRL lesions are commonly detected in symptomatic patients. We have introduced an MRI classification system. PMMRL lesions are significantly associated with age, medial meniscal tears, medial meniscal extrusion, insertional PMMRL osseous change, regional synovitis, osteoarthritis, insufficiency fracture, and cruciate ligament degeneration.

We obtained high-resolution 11.7-T MR images of the pulleys of the flexor tendons in cadaveric toe specimens. A detailed understanding of toe pulley anatomy as seen with MR is likely to be of benefit in recognizing disease and the effects of trauma.Six cadaveric toes were imaged with an 11.7-T small-bore MR imaging system using optimized coils. Two-dimensional dual-echo SE scans were obtained in three planes (40 × 40 × 400-μm(3) voxel size, TE = 7/14 ms, TR = 3,500 ms, fat saturation). Three-dimensional spoiled gradient echo scans were obtained (90-150 μm(3) isotropic voxel size, TE = 6 ms, TR = 25 ms, with and without fat saturation). Specimen orientation was with the long axis of the toe either parallel or perpendicular to B0.All the annular (A) pulleys were demonstrated in the great and lesser toes. The A2 pulley in the great and lesser toes and the A4 pulley in the lesser toes were the most substantial pulleys. The A5 pulley, which has not previously been described in the toes, was demonstrated. The cruciform pulleys were also seen and were smaller and thinner. Three tissue layers were seen, and there was evidence of different fiber directions in annular pulleys producing different magic angle effects.Detailed anatomy of the pulley system of the flexor tendons was seen on the 11.7-T MR images showing new features and providing a basis for image interpretation. Similarities and differences between the pulley systems in the toes and the fingers were identified.