Fluoroscopy-guided injections of the upper extremity: pearls and pitfalls.

Fluoroscopy guidance is commonly utilized for injections in the upper extremity, with increased accuracy for injection placement compared to blind injection. Injection of the glenohumeral joint is the most commonly performed upper extremity procedure. However, there are a number of other sites which can be easily injected under fluoroscopy including the acromioclavicular joint, subacromial subdeltoid bursa, biceps tendon sheath, scapulothoracic bursa, elbow, wrist, first CMC joint, and pisotriquetral joint. Fluoroscopy can be used to guide injections into the glenohumeral, elbow, or wrist joints preceding MR arthrography. While there are technique similarities when injecting any of these sites, some particular approaches and pitfalls are unique to each anatomic site.

ACR Appropriateness Criteria® Suspected Osteomyelitis, Septic Arthritis, or Soft Tissue Infection (Excluding Spine and Diabetic Foot): 2022 Update.

Musculoskeletal infections involve bones, joints, and soft tissues. These infections are a common clinical scenario in both outpatient and emergent settings. Although radiography provides baseline findings, a multimodality approach is often implemented to provide more detailed information on the extent of infection involvement and complications. MRI with intravenous contrast is excellent for the evaluation of musculoskeletal infections and is the most sensitive for diagnosing osteomyelitis. MRI, CT, and ultrasound can be useful for joint and soft tissue infections. When MRI or CT is contraindicated, bone scans and the appropriate utilization of other nuclear medicine scans can be implemented for aiding in the diagnostic imaging of infection, especially with metal hardware and arthroplasty artifacts on MRI and CT. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer-reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances in which peer-reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation.

Imaging of Turf Toe.

Turf toe is a common injury of the hallux metatarsophalangeal (MTP) joint in athletes which is the result of hyperdorsiflexion injury. While the term turf toe has been used to describe a variety of first MTP joint injuries, the term is now typically used in imaging to describe tearing or injury to the plantar plate complex. This review article will cover normal anatomy of the first MTP joint, mechanism of injury, typical imaging findings in normal individuals on MRI and ultrasound, as well as the most common patterns of injury.

Inadvertent intraosseous injection during fluoroscopy-guided joint injection of two adult patients.

Two cases of inadvertent intraosseous injection during fluoroscopy-guided joint injection are presented. The first case occurred during a pre-MRI hip arthrogram while the second case happened during a glenohumeral joint steroid injection. Both cases were performed on osteopenic female patients over 60 years old who reported significant pain during injection of contrast and fluoroscopic imaging showed pooling of contrast in bone during attempted injection. Both procedures were corrected by retracting the needle to achieve intraarticular injection. Being aware of intraosseous injection as a possible reason for difficulty during the procedure both guides the operator to proper correction (retraction of the needle) and also avoids a non-diagnostic or less effective procedure.

Spinal Hematomas: What a Radiologist Needs to Know.

Spinal hematomas are a frequent indication for radiologic evaluation and can be a diagnostic dilemma for many radiologists and surgeons. There are four types of spinal hematomas: epidural, subdural, subarachnoid, and intramedullary (spinal cord) hematomas. Because they differ by their location in relationship to the meningeal membranes and spinal cord, unique radiologic appearances can be recognized to distinguish these types of spinal hemorrhage. Anatomic knowledge of the spinal compartments is essential to the radiologist for confident imaging diagnosis of spinal hematomas and to specify correct locations. MRI is the modality of choice to diagnose the location of the hematoma, characterize important features such as age of the hemorrhage, and detect associated injury or disease. Each type of spinal hematoma has imaging patterns and characteristics that distinguish it from the others, as these specific spinal compartments displace and affect the adjacent anatomic structures. Early detection and accurate localization of spinal hematomas is critical for the surgeon to address the proper treatment and surgical decompression, when necessary, as neurologic deficits may otherwise become permanent. Online supplemental material is available for this article. ©RSNA, 2018.

Accuracy of Opposed-phase Magnetic Resonance Imaging for the Evaluation of Treated and Untreated Spinal Metastases.

RATIONALE AND OBJECTIVES: To assess whether the accuracy of opposed-phase magnetic resonance (MR) imaging to differentiate spinal metastases from benign lesions is influenced by treatment. MATERIALS AND METHODS: We retrospectively evaluated 25 benign lesions, 25 untreated spinal metastases, and 89 treated spinal metastases in 101 patients who underwent opposed-phase MR spine imaging at our institution. The largest possible region of interest was placed over the lesion in question on out-of-phase and in-phase MR sequences, and the signal intensity ratio (SIR) of the lesions was calculated. The SIRs were compared between benign, untreated, and treated lesions. Receiver operator characteristic (ROC) curves were used to identify the optimal threshold to differentiate benign lesions from untreated spinal metastases, and the accuracy of this threshold was assessed for treated spinal metastases, chemotherapy-treated spinal metastases, and radiated spinal metastases. RESULTS: Benign lesions had lower mean SIR than untreated (P = 2.4 × 10-8, 95% confidence interval [0.29, 0.51]) and treated spinal metastases (P = .51; 95% confidence interval [-0.13, 0.06]). A cutoff SIR of 0.856 had an accuracy of 88.00% for untreated lesions, 77.48% for previously treated lesions, and 70.45% for previously radiated lesions. The ROC curve to differentiate benign lesions from radiated spinal metastases was significantly different from the ROC curve to differentiate benign lesions from untreated spinal metastases (P = .0180). The ROC curve to differentiate benign lesions from lesions treated with chemotherapy only was significantly different from the ROC curve to differentiate between benign lesions and radiated spinal metastases (P = .041). CONCLUSIONS: Opposed-phase imaging is less accurate for treated spinal metastases, in particular after radiation.

Point Shear Wave Elastography in Assessment of Hepatic Fibrosis: Diagnostic Accuracy in Subjects With Native and Transplanted Livers Referred for Percutaneous Biopsy.

The objective of this study was to prospectively evaluate the use of point shear wave elastography for the assessment of liver fibrosis and to determine the usefulness and optimal location for obtaining elastography measurements in native and transplanted livers. Point shear wave elastography measurements were obtained from 100 consecutive patients presenting for percutaneous liver biopsy. Measurements were acquired within both the superior right hepatic lobe (segments VII/VIII) via an intercostal approach and the inferior right hepatic lobe (segments V/VI) via a subcostal approach. Analysis of variance was used to assess statistical differences between the degree of fibrosis on percutaneous liver biopsy and elastography measurements. No statistical difference was present when comparing elastography measurements in patients with hepatic steatosis compared with patients without steatosis (P = 0.2759). There was no difference in the accuracy of elastography measurements in native livers versus transplanted livers (P = 0.221). Point shear wave elastography can accurately differentiate between patients with no-to-mild hepatic fibrosis (F0-F1) and moderate-to-severe hepatic fibrosis (≥F2) with sensitivity of 72% and specificity of 69%. Point shear wave elastography can be used as a noninvasive method to assess fibrosis in patients with native or transplanted livers. In addition, measurements can be combined or taken separately from either the superior or inferior right hepatic lobe. The presence of hepatic steatosis does not affect the accuracy of point shear wave elastography. However, shear wave elastography values in patients with body mass index greater than 40 should be interpreted with caution.