RESUMO
Dynamic scintigraphy with lasix (urosemide) in 59 patients with hydronephrosis, nephrolithiasis, chronic pyelonephritis, ureterohydronephrosis on an initial scintigram has shown retention of 99mTc-DTPA in the urinary tracts: an increase or absence of the excretory segment on the activity-time curve up to the appearance of an obstructive type of a curve. Verified operative findings in 19 patients with hydronephrosis and nephrolithiasis have shown a high sensitivity and accuracy of the detection of stenosis of the urinary tracts in the absence of the excretory segment on an initial scintigram irrespective of the fact whether it appears or not on a scintigram after lasix administration. Stenosis of the ureteropelvic segment can be observed in the presence of the excretory segment on an initial scintigram with a prolonged half-period of RP excretion; its 2-fold decrease is noted on a scintigram after lasix administration.
