FDG PET/CT and thyroid biopsy leads to neurosarcoidosis diagnosis.

We present a unique case of neurosarcoidosis diagnosed based on thyroid biopsy and FDG PET (Fluorodeoxyglucose positron emission tomography) imaging. A patient presented for a second opinion after being placed in hospice for rapidly progressing dementia, presumed to be due to Creutzfeldt Jakob disease despite negative workup and was unable to perform activities of daily life or communicate with his wife. The patient underwent a workup including whole-body FDG PET, which showed hypermetabolic lymph nodes as well as a hypermetabolic nodule in the thyroid. Biopsy of the lymph nodes was nondiagnostic, but the thyroid biopsy tissue yielded a diagnosis of sarcoid. After ruling out other causes and reviewing the tissue pathology, the patient was diagnosed with systemic sarcoidosis with neurological involvement and started on infliximab with rapid improvement.

Contrast-enhanced US Evaluation of Endoleaks after Endovascular Stent Repair of Abdominal Aortic Aneurysm.

Ruptured abdominal aortic aneurysm (AAA) carries high morbidity and mortality. Elective repair of AAA with endovascular stent-grafts requires lifetime imaging surveillance for potential complications, most commonly endoleaks. Because endoleaks result in antegrade or retrograde systemic arterialized flow into the excluded aneurysm sac, patients are at risk for recurrent aneurysm sac growth with the potential to rupture. Multiphasic CT has been the main imaging modality for surveillance and symptom evaluation, but contrast-enhanced US (CEUS) offers a useful alternative that avoids radiation and iodinated contrast material. CEUS is at least equivalent to CT for detecting endoleak and may be more sensitive. The authors provide a general protocol and technical considerations needed to perform CEUS of the abdominal aorta after endovascular stent repair. When there are no complications, the stent-graft lumen has homogeneous enhancement, and no contrast material is present in the aneurysm sac outside the stented lumen. In patients with an antegrade endoleak, contrast material is seen simultaneously in the aneurysm sac and stent-graft lumen, while delayed enhancement in the sac is due to retrograde leak. Recognition of artifacts and other potential pitfalls for CEUS studies is important for examination performance and interpretation. Online supplemental material is available for this article. ©RSNA, 2022.

Imaging evaluation for the diagnosis and management of complications of gender-affirming surgeries.

Gender-affirming surgeries (GS) allow transgender individuals to align their physical sexual characteristics with their gender identity, which can result in profound changes to native anatomy. Medical imaging is a useful tool for evaluation of patients who have undergone or plan to pursue GS. Given the complex nature of some GS, complications may arise. The choice of imaging modality can be guided by the clinically suspected complications. For example, urethral complications of phalloplasty are best evaluated with fluoroscopic urethrography. Pelvic magnetic resonance imaging provides detailed depiction of pelvic neo-anatomy after vaginoplasty. Many GS involve the creation of vascular pedicles for tissue grafts, which are at risk of thrombosis and graft ischemia. Doppler ultrasound and computed tomography (CT) angiography are important for diagnosis of these dreaded complications. Moreover, interventional radiologists may participate in endovascular treatments for such complications. Various imaging modalities may assist the surgeon in the postoperative evaluation of patients with suspected complications after GS, and imaging protocol modifications may be required to improve diagnostic accuracy. For example, rectal or neovaginal contrast material may be necessary to ensure accurate imaging evaluation, such as delineation of fistulas. Working together, surgeons and radiologists can ensure accurate imaging assessment while accommodating for patient comfort.