3D excretory MR urography: improved image quality with intravenous saline and diuretic administration.
OBJECTIVE
To assess the effect of diuretic administration on the image quality of excretory magnetic resonance urography (MRU) obtained following intravenous hydration, and to determine whether intravenous hydration alone is sufficient to produce diagnostic quality studies of nondilated upper tracts.


METHODS
A total of 22 patients with nondilated upper tracts were evaluated with contrast-enhanced MRU. All patients received 250 mL of saline intravenously immediately prior to the examination. A total of 11 patients received 10-20 mg furosemide in addition to saline. Imaging was performed with a three-dimensional (3D) and two-dimensional (2D) breathhold spoiled gradient-echo sequences. Excretory MRU images were acquired five minutes after the administration of 0.1 mmol/kg gadolinium and were independently reviewed by two radiologists, who were blinded to the MRU technique. Readers evaluated the calyces, renal pelvis, and ureters qualitatively for degree of opacification, distention, and artifacts on a four-point scale. Statistical analysis was performed using a permutation test.


RESULTS
There was no significant disagreement between the two readers (P=0.14). Furosemide resulted in significant improvement in calyceal and renal pelvis distention (P<0.005), and significant artifact reduction in all upper tract segments (P<0.001) compared to the effect of saline alone.


CONCLUSIONS
Intravenous furosemide significantly improves the image quality of excretory MRU studies obtained following intravenous hydration. Intravenous saline alone is insufficient to produce diagnostic quality studies of the non-dilated upper tracts.
Ergen
F Bilge
FB
Department of Radiology/MRI, University of Michigan Health System, Ann Arbor, Michigan 48109-0003, USA.
Hussain
Hero K
HK
Carlos
Ruth C
RC
Johnson
Timothy D
TD
Adusumilli
Saroja
S
Weadock
William J
WJ
Korobkin
Melvyn
M
Francis
Isaac R
IR
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media; D004232:Diuretics / Q000008:administration & dosage*; D005665:Furosemide / Q000008:administration & dosage*; D005682:Gadolinium; D006801:Humans; D021621:Imaging, Three-Dimensional; D007275:Injections, Intravenous; D007674:Kidney Diseases / Q000175:diagnosis*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008875:Middle Aged; D015588:Observer Variation; D012965:Sodium Chloride / Q000008:administration & dosage*; D014551:Urinary Tract / Q000473:pathology*; D014567:Urography / Q000379:methods*
D003287:Contrast Media; D004232:Diuretics; D012965:Sodium Chloride; D005665:Furosemide; D005682:Gadolinium