COMPARATIVE STUDY OF HELICAL CT SCAN ANGIOGRAPHY AND CONVENTIONAL ARTERIOGRAPHY FOR EVALUATION OF LIVING RENAL TRANSPLANT DONORS

Abstract

291 OBJECTIVES: Conventional arteriography is the most invasive examination for the evaluation of potential renal transplant donors, but this technique is still used as the routine preoperative examination before renal transplantation. This prospective study was designed to assess if the helical CT scan could be a potential substitute for conventional renal arteriography in the evaluation of kidney transplant donors. PATIENTS AND METHODS: Renal transplant donors and patients with renovascular disease were included in this study. All these patients underwent helical CT angiography (HCTA) and conventional renal angiography (CA). The findings obtained by HCTA were compared with those of CA. We defined the criteria to judge visualizability of renal vessels, as well visualized (WV), poorly visualized (PV), and non-visualized (NV). The renal vessels defined as WV could be clearly identified and those as PV could also be identified, but not clearly. We checked the main renal arteries, main branches, and aberrant vessels, and pathological conditions, such as stenosis and aneurysms. Fifty-four renal units in 27 patients were evaluated in this study. RESULTS: With HCTA main renal arteries were WV in 51 of 54 (94.45%) renal units and 3 (5.5%) were PV. The main artery was detectable in all renal units. Using CA, 47 of 54 (87.03%) main arteries were WV, and 7 of 54 (13%) were PV. Also, CA detected all the main arteries. The main branches of the renal artery were WV by HCTA in 38 of 54 (70.37%) renal units, PV in 14 (25.92%) renal units and NV in two renal units (3.7%). CA showed WV images in 47 of 54 renal units (87.03%), PW in 6 (11.11%) renal units and in one case the main branches could not be visualized (1.85%). Stenosis was shown by HCTA as follows: WV in 4 of 6 (66%) renal units, PV in one (16.6%) and the remaining unit was not proven (16.6%). CA visualized well 4 of 6 (66%) stenoses, one was PV (16.6%) and one was not proved (16.6%). For renal artery aneurysms, HCTA showed WV in 5 of 7 (71.4%) renal units and NV in the other 2 units. In one renal unit the lesion was in the renal parenchyma, and in an other renal unit the renal artery aneurysm was occupied by a thrombus. CA showed WV in 3 of 7 (42.8%) renal units, PV in 2 renal units (28.5%), and in 2 renal units the lesion could not be visualized (28.5%). Aberrant vessels and early branches as shown by HCTA were WV in 100% of the 10 renal units. Among these 10 renal units, CA showed WV in 5 (50%) renal units, PV in 4 (40%) and in one unit it did not prove the existence of a polar artery (10%). A comparison of the two methods with surgery showed that HCTA was 96.94% sensitive and CA was 96.18% sensitive. As a final result of both methods, CA showed WV details in 80.91% renal units, PV in 15.26% and NV in 3.81%. HCTA showed WV in 82.44% of the renal units, PV in 13.74% and NV in 3.05%. CONCLUSIONS: The percentage of WV, PV and NV showed by CA was quite similar with HCTA, being slightly advantageous in terms of visualizability of the renal artery and abnormal vessels. HCTA is less invasive than CA, it has at least the same performances and our study suggests that it could be a suitable replacement for conventional renal arteriography for the evaluation of potential kidney donors.