Parsonage-turner syndrome associated with SARS-CoV2 (COVID-19) infection.

Parsonage-Turner Syndrome (PTS), also known as idiopathic brachial plexopathy or neuralgic amyotrophy, is an uncommon condition characterized by acute onset of shoulder pain, most commonly unilateral, which may progress to neurologic deficits such as weakness and paresthesias (Feinberg and Radecki, 2010 [1]). Although the etiology and pathophysiology of PTS remains unclear, the syndrome has been reported in the postoperative, postinfectious, and post-vaccination settings, with recent viral illness reported as the most common associated risk factor (Beghi et al., 1985 [2]). Various viral, bacterial, and fungal infections have been reported to precede PTS, however, currently there are no reported cases of PTS in the setting of recent infection with SARS-CoV2 (COVID-19). We present a case of a 17 year old female patient with no significant past medical or surgical history who presented with several weeks of severe joint pain in the setting of a recent viral illness (SARS-CoV2, COVID-19). MRI of the left shoulder showed uniform increased T2 signal of the supraspinatus, infraspinatus, teres minor, teres major, and trapezius muscles, consistent with PTS. Bone marrow biopsy results excluded malignancy and hypereosinophilic syndrome as other possible etiologies. Additional rheumatologic work-up was also negative, suggesting the etiology of PTS in this patient to be related to recent infection with SARS-CoV2 (COVID-19). Radiologists should be aware of this possible etiology of shoulder pain as the number of cases of SARS-CoV2 (COVID-19) continues to rise worldwide.

Cough-induced costal cartilage fracture.

We present two cases of atraumatic costal cartilage fracture secondary to violent coughing. Although costal cartilage fractures due to trauma and bony rib fractures due to violent coughing have been described, to our knowledge there have been no prior reported cases of cough-induced costal cartilage fracture. It is important for radiologists to consider costal cartilage fractures, which are often more subtle than osseous injuries, in patients with chest pain, and understand that they may not always be preceded by direct trauma. Identifying this injury is clinically important and will prevent patients from undergoing unnecessary examinations to rule out a cardiac cause of chest pain or a pulmonary embolism.

Radiologic evaluation of fracture healing.

While assessment of fracture healing is a common task for both orthopedic surgeons and radiologists, it remains challenging due to a lack of consensus on imaging and clinical criteria as well as the lack of a true gold standard. Further complicating this evaluation are the wide variations between patients, specific fracture sites, and fracture patterns. Research into the mechanical properties of bone and the process of bone healing has helped to guide the evaluation of fracture union. Development of standardized scoring systems and identification of specific radiologic signs have further clarified the radiologist's role in this process. This article reviews these scoring systems and signs with regard to the biomechanical basis of fracture healing. We present the utility and limitations of current techniques used to assess fracture union as well as newer methods and potential future directions for this field.

Arthroscopic primary repair of the anterior cruciate ligament: what the radiologist needs to know.

Recently, there has been a renewed interest in primary repair of proximal anterior cruciate ligament (ACL) tears. Magnetic resonance imaging (MRI) plays an important role in preoperative patient selection and in postoperative ligament assessment. Knowledge of the imaging factors that make patients candidates for primary ACL repair, namely proximal tear location and good tissue quality, can help radiologists provide information that is meaningful for surgical decision making. Furthermore, an understanding of the surgical techniques can prevent misinterpretation of the postoperative MRI. This article reviews preoperative MRI characterization of ACL injuries, techniques of arthroscopic primary ACL repair surgery and examples of postoperative MRI findings.

Brain Magnetic Resonance Imaging for Traumatic Brain Injury: Why, When, and How?

Conventional magnetic resonance imaging (MRI) and angiography (MRA) provide invaluable information in the evaluation of patients with all stages and grades of traumatic brain injury (TBI). The information obtained with MRI provides a more complete assessment of the patient's brain injury and possible long-term sequelae.

Microarray analysis of thyroid nodule fine-needle aspirates accurately classifies benign and malignant lesions.

Current preoperative diagnostic procedures for thyroid nodules rely mainly on the cytological interpretation of fine-needle aspirates (FNAs). DNA microarray analysis has been shown to reliably distinguish benign and malignant thyroid nodules in surgically resected specimens, but its diagnostic potential in thyroid FNA has not been examined. In the present study, the expression profiles of 50 benign thyroid lesions and papillary thyroid carcinoma tissue samples were compared, generating a list of 25 differentially expressed genes from this training set. A test set of 22 FNA specimens was evaluated by unsupervised hierarchical cluster analysis using this gene list, and the results were compared to FNA cytology. FNA specimens were found to fall into three clusters: malignant (n = 10), benign (n = 7), and indeterminate (n = 5). The benign and malignant groups showed complete concordance with the final histological diagnosis except for one histologically benign lesion, which was rediagnosed as follicular variant of papillary thyroid carcinoma on histological review. Paired analysis between FNA and matched tissues samples illustrated adequate sampling with FNA. These results illustrate that microarray analysis of FNA is feasible and has the potential to improve the accuracy of FNA in categorizing benign from malignant lesions beyond routine cytological evaluation.