MIBG Localization of a Subclinical Paraganglioma of the Bladder.

Urinary bladder paragangliomas are very rare, and the majority are hormonally active. Nonfunctioning paragangliomas are even rarer and more difficult to diagnose because of absence of catecholamine secretion. We present a 27-year-old woman with an asymptomatic paraganglioma of the urinary bladder discovered incidentally in a patient with prior resection of a functional pararenal paraganglioma. Metabolic profiles and cystoscopy were nondiagnostic. We demonstrate the increased sensitivity of I-MIBG SPECT/CT compared with planar scintigraphy for detection of a nonfunctional paraganglioma of the urinary bladder, which makes it valuable in evaluation of functional and nonfunctional paragangliomas.

Clinical impact of strict criteria for selectivity and lateralization in adrenal vein sampling.

INTRODUCTION: Selectivity index (SI) and lateralization index (LI) thresholds determine the adequacy of adrenal vein sampling (AVS) and the degree of lateralization. The purpose of this study was investigate the clinical outcome of patients whose adrenal vein sampling was interpreted using "strict criteria" (SC) (SIpre-stimuli≥3, SIpost-stimuli≥5 and LIpre-stimuli≥4, LIpost-stimuli≥4). MATERIALS AND METHODS: A retrospective review of 73 consecutive AVS procedures was performed and 67 were technically successful. Forty-three patients showed lateralization and underwent surgery, while 24 did not lateralize and were managed conservatively. Systolic blood pressure (SBP), diastolic blood pressure (DBP), kalemia (K(+)), and the change in number of blood pressure (BP) medications were recorded for each patient before and after AVS and potential surgery were performed. RESULTS: In the surgery group, BP and K(+) changed respectively from 160±5.3/100±2.0 mmHg to 127±3.3/80±1.9 (p <0.001) and from 3.00±0.10 to 4.4±0.09 (p <0.001). In the medically managed group, BP and K(+) changed respectively from 148±7.3/93±4.3 to 135±3.3/86±1.9 (p <0.001) and from 2.68±0.10 to 4.3±0.09. After surgery or AVS, the patients who took ≥3 blood pressure medications were six (14.0%) in the lateralized group and 22 (91.7%) in the non-lateralized group (p <0.001). CONCLUSIONS: AVS interpretation with SC leads to significant clinical improvement in both patients who underwent surgery and those managed conservatively.