Faculty Bibliography

The diaphragm, the principle muscle of inspiration, is an under-recognized contributor to respiratory disease. Dysfunction of the diaphragm can occur secondary to lung disease, prolonged ventilation, phrenic nerve injury, neuromuscular disease, and central nervous system pathology. In light of the global pandemic of coronavirus disease 2019 (COVID-19), there has been growing interest in the utility of ultrasound for evaluation of respiratory symptoms including lung and diaphragm sonography. Diaphragm ultrasound can be utilized to diagnose diaphragm dysfunction, assess severity of dysfunction, and monitor disease progression. This article reviews diaphragm and phrenic nerve ultrasound and describes clinical applications in the context of COVID-19.

OBJECTIVE:To assess the diagnostic contribution of contrast-enhanced 3D STIR (ce3D-SS) high-resolution magnetic resonance (MR) imaging of peripheral nerve pathology relative to conventional 2D sequences. MATERIALS AND METHODS/METHODS:In this IRB-approved retrospective study, two radiologists reviewed 60 MR neurography studies with nerve pathology findings. The diagnostic contribution of ce3D-SS imaging was scored on a 4-point Likert scale (1 = no additional information, 2 = supports interpretation, 3 = moderate additional information, and 4 = diagnosis not possible without ce3D-SS). Image quality, nerve visualization, and detection of nerve pathology were also assessed for both standard 2D neurography and ce3D-SS sequences utilizing a 3-point Likert scale. Descriptive statistics are reported. RESULTS:The diagnostic contribution score for ce3D-SS imaging was 2.25 for the brachial plexus, 1.50 for extremities, and 1.75 for the lumbosacral plexus. For brachial plexus, the mean consensus scores for image quality, nerve visualization, and detection of nerve pathology were 2.55, 2.5, and 2.55 for 2D and 2.35, 2.45, and 2.45 for 3D. For extremities, the mean consensus scores for image quality, nerve visualization, and detection of nerve pathology were 2.60, 2.80, and 2.70 for 2D and 1.8, 2.20, and 2.10 for 3D. For lumbosacral plexus, the mean consensus scores for image quality, nerve visualization, and detection of nerve pathology were 2.45, 2.75, and 2.65 for 2D and 2.0, 2.45, and 2.25 for 3D. CONCLUSION/CONCLUSIONS:Overall, our study supports the potential application of ce3D-SS imaging for MRN of the brachial plexus but suggests that 2D MRN protocols are sufficient for MRN of the extremities and lumbosacral plexus.

Preoperative ultrasound-guided lateral abdominal wall botulinum toxin injection is a promising method for improving patient outcomes and reducing recurrence rates after ventral hernia repair. A review of the literature demonstrates variability in the procedural technique, without current standardization of protocols. As radiologists may be increasingly asked to perform ultrasound-guided botulinum toxin injections of the lateral abdominal wall, familiarity with the procedure and current literature is necessary.

The global pandemic of coronavirus disease 2019 (COVID-19) has revealed a surprising number of extra-pulmonary manifestations of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. While myalgia is a common clinical feature of COVID-19, other musculoskeletal manifestations of COVID-19 were infrequently described early during the pandemic. There have been emerging reports, however, of an array of neuromuscular and rheumatologic complications related to COVID-19 infection and disease course including myositis, neuropathy, arthropathy, and soft tissue abnormalities. Multimodality imaging supports diagnosis and evaluation of musculoskeletal disorders in COVID-19 patients. This article aims to provide a first comprehensive summary of musculoskeletal manifestations of COVID-19 with review of imaging.

With surging numbers of patients with coronavirus disease 2019 (COVID-19) throughout the world, neuromuscular complications and rehabilitation concerns are becoming more apparent. Peripheral nerve injury can occur in patients with COVID-19 secondary to postinfectious inflammatory neuropathy, prone positioning-related stretch and/or compression injury, systemic neuropathy, or nerve entrapment from hematoma. Imaging of peripheral nerves in patients with COVID-19 may help to characterize nerve abnormality, to identify site and severity of nerve damage, and to potentially elucidate mechanisms of injury, thereby aiding the medical diagnosis and decision-making process. This review article aims to provide a first comprehensive summary of the current knowledge of COVID-19 and peripheral nerve imaging.

The brachial plexus is an intricate anatomic structure with an important function: providing innervation to the upper extremity, shoulder, and upper chest. Owing to its complex form and longitudinal course, the brachial plexus can be challenging to conceptualize in three dimensions, which complicates evaluations in standard orthogonal imaging planes. The components of the brachial plexus can be determined by using key anatomic landmarks. Applying this anatomic knowledge, a radiologist should then be able to identify pathologic appearances of the brachial plexus by using imaging modalities such as MRI, CT, and US. Brachial plexopathies can be divided into two broad categories that are based on disease origin: traumatic and nontraumatic. In the traumatic plexopathy group, there are distinct imaging findings and management methods for pre- versus postganglionic injuries. For nontraumatic plexopathies, having access to an accurate patient history is often crucial. Knowledge of the timing of radiation therapy is critical to diagnosing post-radiation therapy brachial plexopathy. In acute brachial neuritis, antecedent stressors occur within a specific time frame. Primary and secondary tumors of the brachial plexus are not uncommon, with the most common primary tumors being peripheral nerve sheath tumors. Direct extension and metastasis from primary malignancies such as breast and lung cancer can occur. Although diagnosing a brachial plexus anomaly is potentially perplexing, it can be straightforward if it is based on foundational knowledge of anatomy, imaging findings, and pathologic features. ^©RSNA, 2020.

OBJECTIVE:The objective of this study was to determine the prevalence and spectrum of pathology of the fascia lata attachment at the iliac crest (FLAIC) on MRI in asymptomatic patients in order to refine our diagnostic criteria for clinically relevant FLAIC injury. METHODS AND MATERIAL/METHODS:= 200). Pathology of the FLAIC was graded using a 3-point Likert scale and discrepancies were resolved by consensus. RESULTS:< 0.001). There was no statistical difference in FLAIC scores according to gender or age. FLAIC score was positively correlated with higher body mass index. CONCLUSION/CONCLUSIONS:Incidental low to moderate grade FLAIC pathology is commonly seen on MRI in asymptomatic patients. Abnormal MRI findings of the FLAIC should hence be correlated with explicit clinical symptoms and physical exam findings. ADVANCES IN KNOWLEDGE/CONCLUSIONS:The Fascia lata is a complex anatomic structure. Its attachment to the iliac crest is an under recognized pathology and sometimes overlooked during evaluation for pelvis and lateral hip pain. Evaluation of the FLAIC is easily done with MRI and abnormality should be correlated to the clinical symptomatology as low grade abnormality is frequently seen in asymptomatic population.

OBJECTIVE:To determine the utility of intravenous contrast in magnetic resonance neurography (MRN). MATERIALS AND METHODS/METHODS:A search of our PACS for MRN studies performed in 2015 yielded 74 MRN exams, 57 of which included pre- and post-contrast images. All studies were independently reviewed by 3 musculoskeletal radiologists with peripheral nerve imaging experience for presence/absence of nerve pathology, presence/absence of muscle denervation, and contrast utility score based on a 4-point Likert scale. The medical record was reviewed for demographic and clinical data. RESULTS:The mean contrast utility score across all readers and all cases was 1.65, where a score of 1 indicated no additional information and a score of 2 indicated mild additional information/supports interpretation. The mean contrast utility score was slightly higher in cases with a clinical indication of amputation/stump neuroma or mass (2.3 and 2.1 respectively) and lower in cases with a clinical indication of trauma (1.5). The mean contrast utility score was lowest in patients undergoing MRN for pain, numbness, and/or weakness (1.2). CONCLUSION/CONCLUSIONS:Intravenous contrast provides mild to no additional information for the majority of MRN exams. Given the invasive nature of contrast and recent concerns regarding previously unrecognized risks of repetitive contrast exposure, assessment of the necessity of intravenous contrast in MRN is important. Consensus evidence-based practice guidelines regarding intravenous contrast use in MRN are necessary.