[Dynamic scintigraphy of the kidneys using lasix].

Area of Science:

• Nuclear Medicine
• Urology
• Diagnostic Imaging

Background:

• Urinary tract obstruction is a common clinical challenge.
• Accurate diagnosis of conditions like hydronephrosis and nephrolithiasis is crucial.
• Dynamic scintigraphy offers a functional assessment of the urinary system.

Purpose of the Study:

• To evaluate the utility of dynamic scintigraphy with lasix (urosemide) in diagnosing urinary tract obstruction.
• To assess the accuracy of this method in detecting stenosis in patients with hydronephrosis and nephrolithiasis.
• To correlate scintigraphic findings with operative findings.

Main Methods:

• Dynamic scintigraphy using 99mTc-DTPA was performed on 59 patients.
• Lasix (urosemide) was administered to assess urinary tract excretion.
• Activity-time curves were analyzed for retention and excretory patterns.
• Scintigraphic findings were compared with operative findings in 19 patients.

Main Results:

• Retention of 99mTc-DTPA was observed in patients with urinary tract obstruction.
• Absence of an excretory segment on initial scintigrams indicated stenosis with high accuracy.
• Lasix administration improved the detection of stenosis, especially when the excretory segment was initially present but prolonged.
• A 2-fold decrease in the half-period of radiopharmaceutical excretion after lasix indicated ureteropelvic stenosis.

Conclusions:

• Dynamic scintigraphy with lasix is a sensitive and accurate method for detecting urinary tract stenosis.
• The absence of an excretory segment on initial scintigraphy is a strong indicator of obstruction.
• Lasix-enhanced scintigraphy improves the diagnostic capability for ureteropelvic junction obstruction.