Comparing fluorodeoxyglucose positron emission tomography with computed tomography in staging for nodal and distant metastasis in urothelial/bladder cancer.

Objectives: We aim to assess the clinical value of 18F-fluorodeoxyglucose positron (18F-FDG-PET) scan in detecting nodal and distant metastasis compared with computed tomography (CT) scan in patients with urothelial carcinoma or bladder cancer, aiming to improve staging accuracy and thereby better prognosticate and determine therapy. Methods: A retrospective review of 75 patients with invasive bladder cancer (≥T1) who were staged with both CT and 18F-FDG-PET within an 8-week interval was performed for the period between 2015 and 2020. Seventy-two per cent (54/75) had formal pelvic lymph node (LN) dissection or biopsy of lesions suspicious for metastases. FDG-PET definitions for positive sites were assessed depending on SUV Max (nodes with SUVmax >4 at any size, SUV > 2 for lymph nodes >8 mm, or any SUV if the lymph node was >10 mm on axial images). For CT scanning, enlarged LN by RECIST 1.1 criteria (>10 mm) as well as qualitative findings suggesting metastasis were considered positive. The analysis was based on the comparison of CT and 18F-FDG-PET findings to histopathology results from LN dissection or biopsies. Results: Sensitivity, specificity, positive predictive values (PPV) and negative predictive value (NPV) of CT versus FDG-PET for detecting metastasis, in patients who underwent pelvic LN dissection or biopsy of lesions suspicious of metastases, were 46.6% (95% CI: 21%-70%) versus 60% (95% CI: 32%-84%), 100% (95% CI: 91%-100%) versus 83.78% (95% CI: 69%-94%), 100% (95% CI: 63%-100%) versus 60% (95% CI: 32%-84%), and 82.2% (95% CI: 68%-92%) versus 83.78% (95% CI: 69%-94%), respectively. 7/75 (9.3%) patients avoided cystectomy due to 18F-FDG-PET features of metastases that were not detected by CT. Conclusion: FDG-PET may be more sensitive than CT for metastases in the staging of bladder cancer, which resulted in significant avoidance of aggressive local management in cases with occult metastasis.

Os intermetatarseum: An analysis of morphology and case reports of fracture.

INTRODUCTION: The os intermetatarseum is an uncommon accessory ossicle of the foot located dorsally, between the bases of the first and second metatarsals that are usually asymptomatic. In the setting of trauma, this ossicle can clinically mimic a Lisfranc fracture-dislocation, a potentially disabling condition often requiring surgical intervention. METHODS: In this study, 47 cases of os intermetatarseum were reviewed across several Western Australian (WA) Hospitals and characterised based on morphology. Any fractures were recorded, and their cases were reviewed. RESULTS: The most common type of os intermetatarseum was freestanding at 63%, followed by the articulating type at 30%. Only 7% were of the fused type. Two acute fractures were identified on plain radiography and computed tomography (CT). CONCLUSION: The distribution of os intermetatarseum subtypes in the WA population is consistent with previous radiological studies. The two cases of isolated acute os intermetatarseum fracture are described, the first to our knowledge, highlighting the need for increased awareness of this ossicle in the setting of foot trauma.

Contrast-enhanced magnetic resonance angiography of the peripheral arteries: technique, tips, pitfalls and problems.

Contrast-enhanced magnetic resonance angiography is a reliable way to assess peripheral vascular disease. This article reviews the basic physics behind this technique and discusses our institution's experience with regard to the clinical role, recent advances in image acquisition and use of contrast agents. Problems that can affect image quality and interpretation are also highlighted.