[Diagnostic value of HASTE technique and excretory MR urography in urinary system obstructions].
OBJECTIVE
To compare the diagnostic value of static-liquid magnetic resonance urography (MRU) in T2-weighted HASTE (half-fourier acquisition single-shot turbo spinecho) sequences and T1-weighted excretory MRU with i.v. diuretic and contrast material injection.


METHODS
The study included 29 patients (15 men, 14 women). Thirty-one urinary obstructions were detected on intravenous urography (IVU) two of which were due to bilateral obstructions. The cases were evaluated by T2 HASTE sequences combined with T1-weighted FLASH 3D sequences after i.v. diuretics and gadolinium DTPA injection.


RESULTS
Thirty-one urinary obstructions were detected on IVU. Thirty of which were confirmed by T2-weighted MRU and all were confirmed by excretory MRU. In one nonobstructive case, unilateral grade 1 ureteropelvicaliectasis related to ureteral stone was falsely interpreted by both sequences. There were no statistical differences among IVU, T2-weighted MRU and excretory MRU in detecting the obstruction levels. In 22 cases with ureteral stones, 12 of which were confirmed by T2-weighted MRU and 18 cases were confirmed by excretory MRU. Sensitivity and specificity fo detecting the ureteral stones as a cause of obstruction with T2-weighted MRU were 50%and 89% and with excretory MRU were 77% and 89% respectively. In 9 obstructive cases due to causes other than the stones, 8 of which were detected by T2-weighted MRU and all of which were detected by excretory MRU. Sensitivity and specificity for detecting the causes other than the stones with T2-weighted MRU were 96% and 100% and with excretory MRU were 100% and 100% respectively.


CONCLUSIONS
MRU is a useful thechnique revealing high-quality images to determine the urinary system obstructions to obtain the causes of obstructions. MRU should be used as an alternative imaging technique in cases which IVU can not be applied. The existence and the causes of obstruction can be detected by HASTE MRU. Excretory MRU can supply additional information in cases with functional kidneys where the cause of obstruction can not be revealed by HASTE MRU.
Erdoğmuş
Beşir
B
Doğu Tip Görüntüleme Merkezi, Erzurum, Turkey.
Bozkurt
Mahmut
M
Bakir
Zeki
Z
D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D003287:Contrast Media; D004232:Diuretics; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011877:Radionuclide Imaging; D012680:Sensitivity and Specificity; D014567:Urography / Q000379:methods*; D014570:Urologic Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology
D003287:Contrast Media; D004232:Diuretics; D019786:Gadolinium DTPA