RESUMEN
Differential renal blood flow and parenchymal mass were compared in 50 pairs of scintigraphic studies performed on 44 patients. Background corrected total kidney counts were determined between 1 to 2 minutes following injection of I-123 or I-131 orthoiodohippurate (OIH), and at 1 to 2.5 hours after injection of Tc-99m glucoheptonate (GHA). The OIH and GHA differentials agreed within 5% in 36 studies (72%). When the OIH differentials were symmetric (45% to 55% in each kidney), agreement with the GHA results was complete (17 out of 17). By comparison, 42% (14 out of 33) of studies with asymmetric OIH differentials had a greater than 5% disparity from the GHA split function. Serum creatinine was elevated at the time of 9 out of 14 studies (64%) with OIH/GHA disagreement and 18 out of 36 studies (50%) with OIH/GHA agreement. Of the 14 studies with disparate OIH/GHA differentials, the GHA differential was more symmetric in 10 (71%). When different scinitigraphic measures of differential renal flow and parenchymal mass disagree, this is most likely due to the effects of asymmetric renal impairment rather than to those of global renal dysfunction.
Asunto(s)
Radioisótopos de Yodo , Ácido Yodohipúrico , Compuestos de Organotecnecio , Renografía por Radioisótopo/métodos , Azúcares Ácidos , Creatinina/sangre , Humanos , Enfermedades Renales/diagnóstico por imagen , Circulación Renal/fisiología , Obstrucción Ureteral/diagnóstico por imagenRESUMEN
Radioisotope penile plethysmography is a nuclear medicine technique which assists in the evaluation of patients with erectile dysfunction. This technique attempts to noninvasively quantitate penile corpora cavernosal blood flow during early penile tumescence using technetium-99m-labeled red blood cells. Penile images and counts were acquired in a steady-state blood-pool phase prior to and after the administration of intracorporal papaverine. Penile counts, images, and time-activity curves were computer analyzed in order to determine peak corporal flow and volume changes. Peak corporal flow rates were compared to arterial integrity (determined by angiography) and venosinusoidal corporal leak (determined by cavernosometry). Peak corporal flow correlated well with arterial integrity (r = 0.91) but did not correlate with venosinusoidal leak parameters (r = 0.01). This report focuses on the methodology and the assumptions which form the foundation of this technique. The strong correlation of peak corporal flow and angiography suggests that radioisotope penile plethysmography could prove useful in the evaluation of arterial inflow disorders in patients with erectile dysfunction.