Can magnetic resonance angiogram be a reliable alternative for donor evaluation for laparoscopic nephrectomy?

Background: While hand-assisted laparoscopic donor nephrectomy (HLDN) is less invasive, which can encourage kidney donation, it requires more exact information about the renal vascular anatomy because of its limited visual field during nephrectomy. MRA is also an attractive choice because of its minimal invasiveness; further, it is an outpatient-based procedure, it uses non-nephrotoxic contrast material and it has no radiation. The aim of our study was to evaluate the effectiveness of gadolinium enhanced three-dimensional MRA (GdE-3D MRA) in a group of potential live donors who were candidates for HLDN. Methods: From September 2002 to December 2004, 40 potential live renal donors were evaluated prospectively with GdE-3D MRA, and this imaging modality was performed before the gold standard, the intra-arterial digital subtraction angiogram (IA-DSA), was carried out. All the images were reviewed in a blinded manner by the attending vascular radiologist. The MRA findings were compared with the DSA findings and the surgical findings as the reference methods. We evaluated the accuracy of MRA for imaging the renal architectures, and especially for imaging the renal accessory arteries and the early branching arteries that are important determinants for selection of the donor kidney. Results: Both the MRA and DSA images showed consistent findings with the surgical findings in 92.5% of the 40 donors. There were no discrepant cases in depicting the main renal artery. MRA showed 100% specificity for imaging both the renal accessory arteries and the early branching arteries, when compared with the surgical findings. The kappa values for the MRA and DSA for the accessory arteries were all 0.66 compared with the intraoperative findings. MRA also depicted one huge renal cyst in one donor and many small renal cysts in the other donors that could not be imaged by DSA. There were no adverse events during the MRA procedure. None of the findings missed by MRA resulted in deleterious consequences at laparoscopic nephrectomy for the donor and graft. Conclusions: Our limited experience with GdE-3D MRA for imaging the renal structures in kidney donor evaluation for HLDN has been quite satisfactory.