ORIGINAL ARTICLE Comparison of Three Different Diuretic Renal Scintigraphy Protocols in Patients With Dilated Upper Urinary Tracts S¸eyda Tu¨rko¨lmez, MD,* Tamer Atasever, MD,* Kadir Tu¨rko¨lmez, MD,† and Orhan Go¨gu¨s, MD† Purpose: To compare 3 different diuretic renal scintigraphy proto- cols in patients with dilated upper urinary tract. Materials and Methods: Three diuresis renography protocols were performed in 22 adult patients (28 kidneys) with upper urinary tract dilatation. The diuretic was given 20 minutes after (F20), at the same time as (F0), and 15 minutes before (F15) radionuclide administration. The mean age was 29.8 years (range, 18 – 43 years). The 3 protocols were identical, except for the time of injection of furosemide. The F0 protocol could not be performed in 1 and F15 in 2 of the patients. Each of the 3 protocols was performed for the rest of the patients. The results were classified as nonobstructive, equivocal, and obstructive according to the renogram images and curves. Results: None of the patients showed equivocal results in both F0 and F15 protocols. In the F20 studies, 7 of the 28 kidneys were evaluated as equivocal. Of these, 5 kidneys showed nonobstructive and 2 kidneys revealed obstructive renogram patterns with the other 2 protocols (F0 and F15). Moreover, one kidney, which was evaluated as nonobstructive in the F20 protocol, showed an obstructive pattern in both F0 and F15 protocols. All of the kidneys showing obstructive patterns in the F20 study also re- vealed obstruction in the F0 and F15 investigations. We could not find any difference between the renogram patterns of F0 and F-15 investigations. Conclusions: F0 and F15 protocols allow clarification in cases of equivocal F20 studies. Because the F0 study is more practical and shorter, we suggest the F0 method when equivocal results are obtained by an F20 study or as a single test when there is only one opportunity to confirm or exclude the presence of obstruction. Key Words: diuretic renal scintigraphy, diuretic protocols, upper urinary tract dilatation (Clin Nucl Med 2004;29: 154 –160) D iuresis renography is a widely accepted test for the investigation of dilated urinary tracts. 1–3 The purpose of diuretic renography is to differentiate a true obstruction from nonobstructive dilatation. In the standard diuretic renography protocol (F20), diuretic is injected 20 minutes after radio- pharmaceutical administration. However, the F20 diuretic renography procedure shows equivocal test results in approx- imately 15% of the cases. 4–7 Other alternative diuretic ad- ministration methods (F15, F0) are recommended when the F20 study is equivocal. 5,6,8 –12 In the F15 protocol, diuretic is given 15 minutes before the radiopharmaceutical injection. F0 is a less-studied protocol. 13 In this method, radioactive complex and the diuretic are injected together. In the present study, we compared the diagnostic im- pact of these 3 diuretic renography protocols (F20, F15, and F0) in cases with upper urinary tract dilatation MATERIALS AND METHODS Twenty-two adult patients (28 kidneys) with upper urinary tract dilatation were studied. The mean age was 29.8 years (range, 18 – 43 years). Six of the 22 patients had bilateral dilatation. All patients were under the care of a single urology department. Informed consent was obtained from all patients. The study was conducted according to the ethical principles laid down in the latest version of the Declaration of Helsinki. The 3 diuretic protocols were performed within 15 days. There were at least 3 days between the scintigraphic procedures. The 3 protocols were identical, except for the time of furosemide injection. F0 protocol could not be performed in 1 and F15 in 2 of the patients. Each of the 3 protocols was performed for the rest of the patients. Urine analysis, excretory urography, and renal ultrasonography were performed. Serum creatinine levels and 24-hour creat- inine clearance values were determined. In each patient, a final diagnosis was made by the referring physician based on either surgical findings or con- servative management with repeated sonography and renal scans. Thus, the patients were divided into 2 groups. Received for publication July 16, 2003; accepted September 24, 2003. From the Departments of *Nuclear Medicine, Gazi University School of Medicine, and †Urology, Ankara University, School of Medicine, An- kara, Turkey. Reprints: S¸eyda Tu¨rko¨lmez, MD, Firat Cad, Firat Apt, 186/20, Beysukent, Ankara, Turkey; E-mail: sturkolmez@yahoo.com Copyright © 2004 by Lippincott Williams & Wilkins ISSN: 0363-9762/04/2903-0154 DOI: 10.1097/01.rlu.0000113852.57445.23 Clinical Nuclear Medicine • Volume 29, Number 3, March 2004 154