Role Of Mr Angiogaphy In Evaluation Of Potential Living Kidney Donors:

Mohamed Fawzy Attia

Radiographic imaging of the kidney and its circulation is animportant part in the evaluation of potential liVing kidney donors.Before nephrectomy, donors routinely undergo conventionalarteriography for this evaluation, although conventionalarteriography is currently the most accurate method for imagingblood vessels, this technique is invasive, expensive and donorsmay have adverse local or systemic reactions. MR angiography asa non invasive technique would therefore be preferable forevaluation of these healthy potential donors.The objective of this work was to evaluate the role ofMRangiography in studying the reno-vascular anatomy of potentialliVing kidney donors and to compare MRA with I.V-DSA and I.ADSAin evaluation of the number and location of the donor renalarteries and in identification of major reno-vascular abnormalitiesthat may preclude safe renal donation.This study was carried out on 35 potential living kidneydonors in Urology & Nephrology Center, Mansoura University. Alldonors were subjected to the following radiological techniques :_(1) Ultrasonography.(2) U.T.P.(3) I.V-DSA followed by I.V.U.(4) I.A-OSA :- 7 to 10 days after I.V-OSA.(5) MR angiography.(6) Scintigraphic renal assesement using 99mTC-OTPAThe results of these techniques were compared with theoperative findings reported by the surgeon in the written surgicalsheet after nephrectomy. This was available for the 35 donors whowere subjected to nephrectomy.The results of the study showed a sensitivity of 100% by alltechniques, except IV-OSA which was 95.8% specificity 80%, 40%,70%, 90% and overall accuracy 91.4%, 77%, 88.5%, 94.2%, by MRangiography, LV-OSA, LA-OS aortography and LA selective renalangiography respectively.The accuracy was 100%, 95.8%, 100%, 100% in detection ofsingle artery, 80%, 40%, 70%, 90% in detection of double arteriesfor MR angiography, LV-OSA, I.A-OS aortography and LA selectiverenal angiography respectively while the accuracy was 0% indetection of triple arteries by all techniques.Concerning MRA, the results of the 25 donors who weresubjected to MIP and multiplanar reformatted images as apostprocessing, were 94.7%, 66.6%, 88%, and 100%, 83.3%, 96%as regard sensitivity, specificty and overall accuracy by MIP andMPR images respectively.-146-In conclusion, the study demonstrated that MR angiographyhas better sensitivity and specificity as well as overall accuracythan those of LV-OSA and similar sensitivity and better specificitythan LA-OS aortography. So, we can conclude that MRangiography has a potential for replacing LV-OSA and LA-OSaortography and holds a promise as a single examination foranatomical assessment of poteintial liVing kidney donors. Theadvantages of performing MRA rather than LV-OSA and LA-OSAinclude; reduction in patient discomfort, morbidity, invasivenessand radiation exposure to both the donors and medical staff.However, in equivocal and indeterminate cases, LA-OSaortography plus or minus selective renal aniography arerecommended for better assesment, on the other hand, thecombination of MIP and multiplannar reformation images, inspiteof addition of few minutes to the time of interpretation, permitsbetter visulaization of eccentrically located stenosis,superimposition of structures which may simulate the presence ofstenosis and signals in adjacent structures as the veins, which allcorrupt the image quality as seen on MIP images alone.