RESUMO
Renal resistive indexes were measured by Doppler sonography in 12 children undergoing other standard diagnostic studies to evaluate hydronephrosis. Measurement of renal resistive indexes was modified by prior placement of a bladder catheter, oral hydration and administration of 1 mg./kg. furosemide after baseline measurement. Renal resistive indexes were again measured at 10 and 30 minutes after diuretic. While diuretic administration had no measurable influence on 10 nonobstructed kidneys, the elevated 10-minute post-diuretic renal resistive indexes recorded in 10 obstructed kidneys differed significantly from the indexes recorded in the nonobstructed group (p less than 0.001). The highest elevations in renal resistive indexes were recorded in nonpaired kidneys, which included 7 of the 10 kidneys in the obstructed group. In the 3 unilaterally obstructed kidneys the 10-minute post-diuretic renal resistive indexes did not differ significantly. However, renal resistive indexes in these kidneys increased at least 15% over baseline readings after diuretic administration. Diuretic Doppler sonography appears to be another useful method for differentiating functionally significant hydronephrosis from nonobstructive hydronephrosis in children.
Assuntos
Hidronefrose/diagnóstico por imagem , Obstrução Ureteral/diagnóstico por imagem , Resistência Vascular/fisiologia , Criança , Pré-Escolar , Diurese , Furosemida , Humanos , Hidronefrose/etiologia , Hidronefrose/fisiopatologia , Lactente , Artéria Renal/fisiopatologia , Circulação Renal , Pentetato de Tecnécio Tc 99m , Ultrassonografia/métodos , Obstrução Ureteral/complicações , Obstrução Ureteral/fisiopatologiaRESUMO
The authors prospectively evaluated the accuracy of the resistive index (RI) in Doppler ultrasound (US) for the detection of the increased vascular resistance that theoretically occurs with acute liver transplant rejection. RIs were calculated for the proximal hepatic artery and a more distal hepatic artery branch in 67 liver transplant recipients. Biopsies were performed within 24 hours of transplantation, with no intervening therapy. Examination of biopsy specimens by a single pathologist revealed findings of no, minimal, or moderate to severe rejection. RIs in hepatic arteries showed no significant differences among the three pathologic groups. No correlation was found between the RI and improved or worsened rejection in 11 patients who underwent biopsy and US more than once. RIs in hepatic arteries are of no value in the prediction of liver transplant rejection.
