[Uptake of DL-3-123I-iodo-alpha-methyltyrosine in recurrent brain tumors]. / Anreicherung von DL-3-123I-Jod-alpha-methyltyrosin in Hirntumorrezidiven.

DL-3-123I-iodo-alpha-methyltyrosine (123I-IMT) is a radiopharmacon which concentrates in brain tumors and can be employed in SPECT. We performed 20 studies in 16 patients after neurosurgery for malignant brain tumors (localization of the primary tumor by CT/MRI). Tumor/non-tumor ratios (T/NT) were calculated in ROI-technique. In 17 cases there was a recurrence or tumor remnant. 14/17 were detectable by increased uptake (T/NT 1.43-2.25). The scans were correlated with CT/MRI studies and validated by biopsy (6/14) or follow-up. All 3 patients without recurrence (neuroradiological follow-up over 6-24 months) had a negative scan. 123I-IMT scintigraphy provides complementary information to CT and MRI. In equivocal neuroradiological or clinical cases it may be valuable in the detection of tumor recurrences and allows an earlier onset of therapy.

[Congenital malformations of the urinary tract. Rational postpartum diagnosis]. / Angeborene Fehlbildungen des Harntrakts. Rationelle postpartale Diagnostik.

More than one third of the anomalies diagnosed antenatally by ultrasound comprises the urinary tract. The criteria of the diagnostic and therapeutic approach, which resulted from our experience in children with symptomatic urinary tract anomalies cannot be necessarily applied to asymptomatic newborns. Not all urinary tract anomalies are obstructive and need surgical correction. Therefore, rational diagnostic approach after birth is necessary, which starts with ultrasonography. The first radiological diagnostic procedure is always a voiding cystourethrography in order to diagnose or exclude infravesical obstruction or a vesicoureteric reflux. The dynamic radionuclide nephrography (123I-Hippuran) under standardized conditions with adequate hydration and Furosemide-induced diuresis is able to detect a significant obstruction at the pelvi-ureteric or uretero-vesical junction. The intravenous urography is limited to specific questions and a computerized tomography is rarely indicated. In rare cases when dynamic investigations are equivocal, antegrade pressure flow studies according to Whitaker can be reliably exclude or prove obstruction.

[The diagnostic value of captopril radionuclide nephrography for renovascular hypertension in childhood]. / Diagnostische Bedeutung der Captopril- Radionuklidnephrographie für die renovaskuläre Hypertonie im Kindesalter.

In four children the role of captopril-radionuclide nephrography in the diagnosis of renovascular hypertension was studied. Captopril (0.5-1.0 mg/kg orally) did not affect Iodine-123 Hippuran nephrography in two children with mild renal artery stenosis, but induced an accumulation of the tracer within the kidneys in two children with hemodynamically significant renal artery stenosis. As in adults Iodine 123 Hippuran nephrography appears to be a useful tool to identify patients with significant renal artery stenosis.