MR urography for the preoperative evaluation of living renal donors

Abstract

The purpose of this study was to assess the image quality and diagnostic value of MR urography in detecting abnormalities of the urinary collecting system relevant for the preoperative evaluation of living renal donors. Study subjects were selected from the existing intravenous urography (IVU) reports: 18 consecutive patients with a duplication or another abnormality of the collecting system and 20 consecutive patients with normal anatomy. They underwent a respiratory-triggered 3D T2-weighted fast spin-echo acquisition after oral administration of furosemide, without and with abdominal compression. The MR images were evaluated by two independent blinded observers. The IVU was used as the standard of reference. Image quality of the MR urograms with compression was overall better than those without compression, and the former were regarded as adequate for the evaluation of small filling defects and deformities of the pelvis and calyces in 76-81% of the kidneys and 74-79% of the patients. Both observers correctly diagnosed all 13 kidneys with a partial or complete duplication. The image quality of MR urography was inadequate to evaluate the calyces and pelvis for small filling defects or deformities in approximately 25% of the patients; however, the technique was accurate in the detection of abnormalities of the urinary collecting system relevant for the preoperative evaluation of living renal donors.

Magnetic resonance urography for the assessment of potential renal donors: comparison of the RARE technique with a low-dose gadolinium-enhanced magnetic resonance urography technique in the absence of pharmacological and mechanical intervention

“…Thus, it allows the use of higher doses, up to 0.1 mmol/kg body weight, and provides better image quality [5]. Three papers have reported on the successful use of a Gd-enhanced MRU technique following the intravenous administration of furosemide in renal donors [21][22][23]. In all these studies, the achieved MRU results were considered diagnostic.…”

“…Heavily T2-weighted sequences, such as rapid acquisition with relaxation enhancement (RARE) or half-Fourier acquisition turbo spin-echo (HASTE), and Gd-enhanced excretory MRU techniques, with and without pharmacological manipulation, have been proposed [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. Successful, comprehensive, evaluation of the urinary system for renal donors has been described, both with 3D T2-weighted (T2W) fast spin-echo acquisitions and with Gd-enhanced techniques [21][22][23]. However, in all three papers, diuretics were given and abdominal compression was applied.…”

Caveats when interpreting intravenous urograms following ileal orthotopic bladder substitution

“…However, it does not allow detection of smaller urothelial tumors in a substantial number of patients [20]. This issue may be of particular importance in the follow-up of patients operated for bladder cancer.…”

Filling defect artefacts in magnetic resonance urography

“…Magnetic resonance urography is gaining popularity as an alternative technique of urinary tract imaging in a wide range of clinical settings [1,2,3,4,5,6,7,8,9,10,11,12,13,14]. The introduction of heavily T2-weighted very fast-spin-echo sequences, such as rapid acquisition with relaxation enhancement (RARE), half-Fourier acquisition single-shot turbo spin echo (HASTE) and similar modifications, allowed high-quality MRU and reduced breathing-related artefacts [1,2,3,4,5].…”