The diagnostic performance of MRI signs to distinguish Pectoralis major tendon avulsions from Myotendinous injuries.

BACKGROUND: Management of pectoralis major (PM) injuries is largely determined by the anatomic location of the injury, with tendon avulsions from the humerus requiring surgery while myotendinous (MT) injuries are typically managed non-operatively. Because physical examination cannot reliably make this distinction, MRI is often used for staging. However, correct classification can also be difficult with MRI where there is extensive soft tissue edema and distorted anatomy. OBJECTIVE: To determine the diagnostic performance of primary and secondary MRI signs of PM injury for distinguishing tendon avulsions from MT injuries in a selected sample of patients that underwent surgical repair using a practical interpretation algorithm. METHODS: In this retrospective study, 3 blinded observers independently assessed the MRI findings of 17 patients with PM injury (including 12 acute injuries, 4 chronic, and 1 of uncertain age) where subsequent surgery documented tendon avulsion (11) and MT injuries (6) by applying the primary MRI criteria of absent tendon at the humerus, retracted tendon stump, epicenter of edema, and the secondary finding of soft tissue edema contacting the anterior humeral cortex. Operative findings were used as the reference standard. Sensitivity, specificity, and positive and negative predictive value were recorded for each finding. RESULTS: The primary MRI finding of lack of a visible tendon at the insertion (sensitivity 82-100%, specificity 100%) and the secondary finding of edema contacting the anterior humeral cortex (sensitivity 64-91%, specificity 67-100%) were both useful for the distinction of tendon avulsion from MT injury, particularly in acute injuries. The presence of a retracted tendon stump and the epicenter of edema were not reliable findings. The use of a decision tree including the secondary finding of humeral edema increased the sensitivity and specificity for 2 of the 3 observers. CONCLUSION: MRI assessment of PM injury focused on the humeral insertion of the PM tendon allows accurate distinction of tendon avulsion from MT injury. CLINICAL IMPACT: This study describes a practical approach to classifying PM injuries with MRI to distinguish injuries that require surgery from those that can potentially be managed conservatively.

Performance of electrophysiology procedures at an academic medical center amidst the 2020 coronavirus (COVID-19) pandemic.

A global coronavirus (COVID-19) pandemic occurred at the start of 2020 and is already responsible for more than 74 000 deaths worldwide, just over 100 years after the influenza pandemic of 1918. At the center of the crisis is the highly infectious and deadly SARS-CoV-2, which has altered everything from individual daily lives to the global economy and our collective consciousness. Aside from the pulmonary manifestations of disease, there are likely to be several electrophysiologic (EP) sequelae of COVID-19 infection and its treatment, due to consequences of myocarditis and the use of QT-prolonging drugs. Most crucially, the surge in COVID-19 positive patients that have already overwhelmed the New York City hospital system requires conservation of hospital resources including personal protective equipment (PPE), reassignment of personnel, and reorganization of institutions, including the EP laboratory. In this proposal, we detail the specific protocol changes that our EP department has adopted during the COVID-19 pandemic, including performance of only urgent/emergent procedures, after hours/7-day per week laboratory operation, single attending-only cases to preserve PPE, appropriate use of PPE, telemedicine and video chat follow-up appointments, and daily conferences to collectively manage the clinical and ethical dilemmas to come. We discuss also discuss how we perform EP procedures on presumed COVID positive and COVID tested positive patients to highlight issues that others in the EP community may soon face in their own institution as the virus continues to spread nationally and internationally.

Clinical and cardiac characteristics of COVID-19 mortalities in a diverse New York City Cohort.

INTRODUCTION: Electrocardiographic characteristics in COVID-19-related mortality have not yet been reported, particularly in racial/ethnic minorities. METHODS AND RESULTS: We reviewed demographics, laboratory and cardiac tests, medications, and cardiac rhythm proximate to death or initiation of comfort care for patients hospitalized with a positive SARS-CoV-2 reverse-transcriptase polymerase chain reaction in three New York City hospitals between March 1 and April 3, 2020 who died. We described clinical characteristics and compared factors contributing toward arrhythmic versus nonarrhythmic death. Of 1258 patients screened, 133 died and were enrolled. Of these, 55.6% (74/133) were male, 69.9% (93/133) were racial/ethnic minorities, and 88.0% (117/133) had cardiovascular disease. The last cardiac rhythm recorded was VT or fibrillation in 5.3% (7/133), pulseless electrical activity in 7.5% (10/133), unspecified bradycardia in 0.8% (1/133), and asystole in 26.3% (35/133). Most 74.4% (99/133) died receiving comfort measures only. The most common abnormalities on admission electrocardiogram included abnormal QRS axis (25.8%), atrial fibrillation/flutter (14.3%), atrial ectopy (12.0%), and right bundle branch block (11.9%). During hospitalization, an additional 17.6% developed atrial ectopy, 14.7% ventricular ectopy, 10.1% atrial fibrillation/flutter, and 7.8% a right ventricular abnormality. Arrhythmic death was confirmed or suspected in 8.3% (11/133) associated with age, coronary artery disease, asthma, vasopressor use, longer admission corrected QT interval, and left bundle branch block (LBBB). CONCLUSIONS: Conduction, rhythm, and electrocardiographic abnormalities were common during COVID-19-related hospitalization. Arrhythmic death was associated with age, coronary artery disease, asthma, longer admission corrected QT interval, LBBB, ventricular ectopy, and usage of vasopressors. Most died receiving comfort measures.

Quantitative Variable Assessment of Patellar Instability: An MRI-Based Study.

OBJECTIVE. The purpose of this study was to investigate the reproducibility of three quantitative MRI parameters associated with patellar instability and to determine whether they measure anatomic predisposition to patellar instability individually or in combination with the other parameters. MATERIALS AND METHODS. In this retrospective study, 100 patients diagnosed with a patellar dislocation injury and 100 age- and sex-matched control patients were examined using MRI. The distance between the tibial tubercle and posterior cruciate ligament (TT-PCL), distance between the tibial tubercle and trochlear groove (TT-TG), and TG depth (trochlear dysplasia) were measured independently by three fellowship-trained musculoskeletal radiologists. Intraclass correlation coefficient (ICC) was used to assess intraobserver and interobserver reliability. The parameters in both groups were tested for interdependence on each other and were compared for prevalence and association with patellar instability. RESULTS. All three parameters showed almost perfect intraobserver (TT-PCL ICC, ≥ 0.88; TT-TG ICC, 0.96; trochlear dysplasia ICC, ≥ 0.92) and interobserver (TT-PCL ICC, 0.82; TT-TG ICC, 0.94; trochlear dysplasia ICC, 0.91) reliability and were significantly more common in the patellar instability group. Trochlear dysplasia had the highest association with patellar instability, both as a unique parameter and in pairwise combination with an abnormal TT-TG. Optimal cutoff thresholds for normal TT-TG and TT-PCL were 15.00 mm or less and 21.30 mm or less, respectively. The optimal normal cutoff threshold for evaluating trochlear dysplasia via trochlear depth was 4.95 mm or more. CONCLUSION. Patellar instability is multifactorial. Highly reproducible parameters derived from MRI reveal both unique and overlapping anatomic predispositions, and considering all parameters together may help individualize patient management when selecting orthopedic procedures.

Core curriculum online lecture series in musculoskeletal imaging: initial results.

OBJECTIVE: To augment the educational resources available to training programs and trainees in musculoskeletal (MSK) radiology by creating a comprehensive series of Web-based open-access core curriculum lectures. MATERIALS AND METHODS: Speakers with recognized content and lecturing expertise in MSK radiology were invited to create digitally recorded lecture presentations across a series of 42 core curriculum topics in MSK imaging. Resultant presentation recordings, organized under curriculum subject headings, were archived as open-access video file recordings for online viewing on a dedicated Web page (http://radiologycorelectures.org/msk/). Information regarding the online core curriculum lecture series was distributed to members of the International Skeletal Society, Society of Skeletal Radiology, Society of Chairs of Academic Radiology Departments, and the Association of Program Directors in Radiology. Web page and online lecture utilization data were collected using Google Analytics (Alphabet, Mountain View, CA, USA). RESULTS: Forty-two lectures, by 38 speakers, were recorded, edited and hosted online. Lectures spanned ACGME curriculum categories of musculoskeletal trauma, arthritis, metabolic diseases, marrow, infection, tumors, imaging of internal derangement of joints, congenital disorders, and orthopedic imaging. Online access to the core curriculum lectures was opened on March 4, 2018. As of January 20, 2019, the core curriculum lectures have had 77,573 page views from 34,977 sessions. CONCLUSIONS: To date, the MSK core curriculum lecture series lectures have been widely accessed and viewed. It is envisioned that the initial success of the project will serve to promote ongoing content renewal and expansion to the lecture materials over time.

Cardiac electrophysiology consultative experience at the epicenter of the COVID-19 pandemic in the United States.

BACKGROUND: The COVID-19 pandemic has greatly altered the practice of cardiac electrophysiology around the world for the foreseeable future. Professional organizations have provided guidance for practitioners, but real-world examples of the consults and responsibilities cardiac electrophysiologists face during a surge of COVID-19 patients is lacking. METHODS: In this observational case series we report on 29 consecutive inpatient electrophysiology consultations at a major academic medical center in New York City, the epicenter of the pandemic in the United States, during a 2 week period from March 30-April 12, 2020, when 80% of hospital beds were occupied by COVID-19 patients, and the New York City metropolitan area accounted for 10% of COVID-19 cases worldwide. RESULTS: Reasons for consultation included: Atrial tachyarrhythmia (31%), cardiac implantable electronic device management (28%), bradycardia (14%), QTc prolongation (10%), ventricular arrhythmia (7%), post-transcatheter aortic valve replacement conduction abnormality (3.5%), ventricular pre-excitation (3.5%), and paroxysmal supraventricular tachycardia (3.5%). Twenty-four patients (86%) were positive for COVID-19 by nasopharyngeal swab. All elective procedures were canceled, and only one urgent device implantation was performed. Thirteen patients (45%) required in-person evaluation and the remainder were managed remotely. CONCLUSION: Our experience shows that the application of a massive alteration in workflow and personnel forced by the pandemic allowed our team to efficiently address the intersection of COVID-19 with a range of electrophysiology issues. This experience will prove useful as guidance for emerging hot spots or areas affected by future waves of the pandemic.

MR and ultrasound of the hands and wrists in rheumatoid arthritis. Part II. Added clinical value.

Advanced imaging has become just as vital for diagnosing, staging, and monitoring disease in rheumatoid arthritis (RA) patients as it is for cancer patients. Part 1 of this review discussed synovitis, tenosynovitis, erosions, and osteitis-key imaging findings that occur in patients with RA. Part 2 will now show how these features, in combination with clinical and serologic data, can assist clinical decision-making at various stages of a patient's disease course. Specifically, assessing current disease activity and prognosticating future aggressiveness inform treatment decisions at initial presentation, during medical treatment, and at clinical remission. In addition to summarizing the current literature on advanced imaging in RA, clinical examples from different stages throughout the disease course will illustrate practical approaches for applying these research results. Last, this review will describe potential future roles of imaging in RA patients.

MRI and ultrasound of the hands and wrists in rheumatoid arthritis. I. Imaging findings.

The management of patients with rheumatoid arthritis (RA) has rapidly evolved with the development of newer disease-modifying drugs and the recognition that long-term damage can be mitigated by an earlier and more-informed use of these medications. Historically, radiographs were the mainstay of imaging in RA patients, but radiographic joint narrowing and erosions are late and insensitive findings in the disease. MRI (with intravenous contrast agent) and ultrasound (with power Doppler interrogation) of the hands and wrists are able to demonstrate erosions earlier and with greater sensitivity than radiographs. More importantly, these imaging studies also depict synovitis and active soft-tissue inflammation, which represents a precursor to structural damage. Additionally, MRI can show inflammation within the bones (osteitis), which is proving to be the most important prognosticator of an aggressive disease course. Part I of this review discusses the imaging techniques, pitfalls, definitions, and comparative studies of MRI and ultrasound for identifying and quantifying erosions, synovitis, and osteitis. Part II will demonstrate how these imaging findings influence the clinical management of RA patients throughout their disease course, from presentation through clinical remission.

Normal Pacinian corpuscles in the hand: radiology-pathology correlation in a cadaver study.

OBJECTIVE: To provide microdissection and histological confirmation of normal Pacinian corpuscles prospectively identified using MRI in a cadaver model. METHODS: 3-T MRI of a cadaveric hand specimen was performed with fiduciary markers on the skin. Based on previous descriptions, subcutaneous nodules representing presumed Pacinian corpuscles were localized with respect to the skin markers, and their sizes and depths were recorded. Focused ultrasound was performed to attempt to visualize the corpuscles. Subsequent microdissection was then performed and the presence and location of Pacinian corpuscles were recorded and compared with the findings on MRI. Histological evaluation for each identified corpuscle was performed. RESULTS: The MRI demonstrated 11 T2-hyperintense palmar subcutaneous nodules around the second through fifth metacarpophalangeal joints. None was visible sonographically. The first eight were dissected and proved to be normal Pacinian corpuscles histologically. In sites devoid of subcutaneous nodules on MRI, subsequent dissection failed to reveal any corpuscles. CONCLUSION: On MRI, normal Pacinian corpuscles appear as round or oval, T2-hyperintense subcutaneous nodules in the palms, clustered around the metacarpophalangeal joints, and should not be mistaken for pathological conditions.

Imaging the Postoperative Knee Meniscus: An Evidence-Based Review.

OBJECTIVE: Unenhanced MRI, indirect MR arthrography, direct MR arthrography, and CT arthrography are each currently used to evaluate patients with recurrent knee pain after meniscus surgery. The purpose of this study is to review the evidence for the use of these examinations in patients with suspected recurrent meniscus tear. CONCLUSION: Direct and indirect MR arthrography are superior to conventional MRI for the assessment of the postoperative meniscus after meniscus repair or partial meniscectomy involving more than 25% of the meniscus.

Postoperative Imaging of the Knee Extensor Mechanism.

The extensor mechanism of the knee plays an important role in many movements of the lower extremity. Although its main function is to extend the knee, it also stabilizes the patellofemoral joint and resists passive flexion of the knee when landing from jumping. Pathologic conditions of the extensor mechanism can be acute or chronic, and they can negatively affect daily activities. Fortunately, many surgical treatments are available aimed at restoring function to the injured extensor mechanism. Understanding the surgical techniques and common complications of these procedures enables the radiologist to recognize expected and unexpected postoperative imaging appearances.

Pacinian corpuscles: an explanation for subcutaneous palmar nodules routinely encountered on MR examinations.

Pacinian corpuscles, the main touch receptors to pressure and vibration, are ubiquitous in the deep dermis and hypodermis of the fingers and palms. Nevertheless, their existence is largely unknown to most radiologists. We frequently noted hyperintense nodules in the palms of patients on water-sensitive MRI sequences, but were unable to explain their etiology. We recently encountered two patients who had Pacinian corpuscles identified at surgical exploration and pathological analysis. Pre-operative MRI examinations in these patients showed T2 hyperintense subcutaneous palmar nodules corresponding to these corpuscles in a pattern identical to those seen incidentally in other patients. Descriptions from the dermatopathological and orthopedic literature closely correspond to our MRI observations. Based on these data, we hypothesize that the MRI finding that we previously noted represents normal Pacinian corpuscles.

Impact of an Interactive Diagnostic Case Simulator on a Medical Student Radiology Rotation.

OBJECTIVE: The objective of our study was to assess the short-term impact of adding an interactive simulator to a medical student radiology clerkship. We hypothesized that transitioning students from passive observers to active participants in the reading room would create an appealing and effective learning experience for the current generation of students. MATERIALS AND METHODS: An interactive workstation that provided diagnostic simulations of 84 cases selected to maximize exposure to important diagnoses in musculoskeletal (MSK) radiology was created. From February 2015 through July 2016, 83 students on the radiology elective rotated through MSK: 40 in the traditional observational role and 43 with the MSK simulator. At the end of the rotation, all students completed general radiology and MSK-based competency examinations. The students who used the interactive workstation completed a survey about their experience. RESULTS: MSK competency scores were significantly better for students who rotated with the interactive workstation compared with students in the traditional observational role (mean scores, 71% and 51%, respectively; p < 0.0001). There was no difference in end-of-rotation general competency scores between the groups (mean, 86% and 85%; p = 0.32). Ninety-one percent of students reported the simulator had at least a moderately positive impact on their radiology experience. All students (100%) reported that learning was improved and recommended establishing workstations for other subspecialties. Twenty-one percent of students reported that their experience using the simulator had a positive impact on considering radiology as a career choice. CONCLUSION: Using a reading room-based diagnostic radiology case simulator improves medical student learning, enables self-directed learning, and improves overall experience on the radiology clerkship, positively impacting consideration of radiology as a career.

Appropriate Use Criteria in Musculoskeletal Imaging.

In the United States, health care costs are spiraling upward at an unsustainable rate. Concurrently, medical specialties, legislatures, and the population each recognize the need to prove that current medical practices are effective, measured by outcomes. These forces necessitate a change in radiology's role, from emphasizing interpretation and reporting to maintaining and demonstrating quality and value. An important part of this task involves establishing the appropriateness of imaging tests by application of objective data and expert opinion in an effort to optimize resource utilization and modality selection. We explore the justifications for establishing appropriateness use criteria, various paradigms that have been applied to their creation, inherent limitations of appropriateness rules based on imperfect data, and challenges associated with their widespread implementation and utilization. An appendix of key terms that may be unfamiliar to radiologists is included for future reference.

Primary Rosai-Dorfman disease of the femur.

We report a 19-year-old man with the rare occurrence of primary osseous Rosai-Dorfman disease (RDD). The patient presented with a painful, solitary, bone marrow-replacing lesion in the distal femur. A diagnosis of chronic osteomyelitis was initially made on tissue from a CT-guided needle biopsy of the lesion; however, the diagnosis of RDD was eventually made after histological and immunohistochemical analysis of material from a subsequent curettage. No lymphadenopathy or other sites of involvement were found on clinical evaluation and PET-CT. To our knowledge, this is the first report of solitary osseous RDD based on systemic staging with PET-CT. We review the clinical, imaging, and histological features of primary osseous RDD, including pitfalls in diagnosis.

Bone-remodeling transcript levels are independent of perching in end-of-lay white leghorn chickens.

Osteoporosis is a bone disease that commonly results in a 30% incidence of fracture in hens used to produce eggs for human consumption. One of the causes of osteoporosis is the lack of mechanical strain placed on weight-bearing bones. In conventionally-caged hens, there is inadequate space for chickens to exercise and induce mechanical strain on their bones. One approach is to encourage mechanical stress on bones by the addition of perches to conventional cages. Our study focuses on the molecular mechanism of bone remodeling in end-of-lay hens (71 weeks) with access to perches. We examined bone-specific transcripts that are actively involved during development and remodeling. Using real-time quantitative PCR, we examined seven transcripts (COL2A1 (collagen, type II, alpha 1), RANKL (receptor activator of nuclear factor kappa-B ligand), OPG (osteoprotegerin), PTHLH (PTH-like hormone), PTH1R (PTH/PTHLH type-1 receptor), PTH3R (PTH/PTHLH type-3 receptor), and SOX9 (Sry-related high mobility group box)) in phalange, tibia and femur. Our results indicate that the only significant effect was a difference among bones for COL2A1 (femur > phalange). Therefore, we conclude that access to a perch did not alter transcript expression. Furthermore, because hens have been used as a model for human bone metabolism and osteoporosis, the results indicate that bone remodeling due to mechanical loading in chickens may be a product of different pathways than those involved in the mammalian model.

Electrophysiological mapping and radiofrequency catheter ablation for ventricular tachycardia in a patient with peripartum cardiomyopathy.

A 38-year-old female with prior failed endocardial ablation for ventricular tachycardia (VT) was referred for further treatment. She had been diagnosed with peripartum cardiomyopathy 7 years before and had persistent left ventricular dysfunction with an ejection fraction of 20%. Epicardial voltage mapping showed extensive epicardial scar despite absence of endocardial scar. Five distinct VT morphologies were induced. Ablation was aided by electrogram characteristics, pace mapping, entrainment mapping, and establishing electrical inexcitability along areas of epicardial scar. After epicardial ablation no sustained VT was induced. She had been doing well without VT occurrence but died 1 year later unexpectedly at home.

Femoroacetabular impingement: fact, fiction, or fantasy?

OBJECTIVE: Proponents of femoroacetabular impingement (FAI) now claim that FAI is an important risk factor for hip osteoarthritis and argue that early, aggressive treatment is indicated to stave off long-term complications. The result is more young patients undergoing corrective surgery; does the literature support these claims or has hype trumped reality? This article critically reviews these assertions together with the current scientific evidence that defends (or refutes) them. CONCLUSION: Each reader will need to weigh the evidence carefully when interpreting images or planning management for patients with possible FAI.