All patients with pheochromocytomas should be screened for MEN-2 and von Hippel-Lindau disease to avert further morbidity and mortality in the patients and their families. All patients in families with MEN-2 or von Hippel-Lindau disease should be screened for pheochromocytoma, even if they are asymptomatic.
RARE-MR-urography (Rapid Acquisition with Relaxation Enhancement) is a fast MR imaging technique (6.4 s/acquisition) that selectively depicts fluid by heavy T2-weighting. From 9/1989 to 11/1990, RARE-MR urograms were prospectively evaluated in the diagnosis of upper urinary tract abnormalities in 55 children. The method is performed in several planes and combined with a coronal, T1-weighted spin-echo sequence. Forty out of 42 kidneys with dilated renal pelvis, and 21 out of 24 dilated ureters were identified, only the mildly dilated ones were missed. Even in non-functioning kidneys the urinary tract was clearly depicted by RARE-MR-urography. However, no differentiation could be made with this technique between vesicoureteral reflux and non-refluxing dilatation of ureter and/or renal pelvis. All 19 pelviureteric obstructions and all eight renal duplications with a dilated segment were identified. RARE-MR-urography is a new tool for diagnosing urinary tract abnormalities in children without having to employ ionizing radiation, contrast media, or general anesthesia. A dilated urinary tract can be shown in one image displaying the entire urinary system, similar to excretory urography. The technique is presently not able to provide the information of voiding cystourethrography or renal scintigraphy, nor is it as easy to perform as ultrasound. However, in certain cases it may replace excretory urography.
Forty-four patients with a left-sided idiopathic varicocele were examined with bidirectional Doppler ultrasound (US), physical examination, and percutaneous retrograde venography. On the basis of the Doppler findings, the varicoceles were classified as either stop type or shunt type. On venography, the stop-type varicoceles showed only retrograde blood flow (reflux) in the testicular (internal spermatic) vein, whereas each shunt-type varicocele showed both retrograde and orthograde (i.e., physiologic) venous blood flow: First, reflux appeared in the testicular vein, then orthograde flow occurred in the deferential vein, cremasteric vein, or both. The shunt-type varicocele therefore represented a kind of venous bypass. Thus, the existence of two hemodynamically different types of varicocele as suggested initially by Doppler US is confirmed by percutaneous retrograde venography. The shunting of venous blood appears to be a precondition for medium and large varicoceles and might have some prognostic significance for subfertility associated with varicoceles.
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