Diffusion-weighted MRI of kidneys in healthy volunteers and living kidney donors.

AIM: To establish the normal apparent diffusion coefficient (ADC) values in healthy kidneys, comparing them with the literature, and assessing the correlation between ADC values, creatinine blood level, and glomerular filtration rate (GFR). MATERIALS AND METHODS: Twenty-four healthy volunteers and 26 living kidney donors were examined on a 1.5 T magnetic resonance imaging (MRI) unit. Two diffusion-weighted imaging (DWI) sequences were included in the study protocol (protocol 1 with 16 b-values, protocol 2 with 10 b-values) before the examination blood and urine samples were collected. The GFR was calculated using Cockcroft & Gault and MDRD (Modification of Diet In Renal Disease) formulas and the ADC values were measured separately for the cortex and medulla of each kidney by two independent observers. All statistical analyses were performed using the STATISTICA (version 10.0) software package. Data were analysed using an unpaired t-test; p < 0.05 indicated a statistically significant difference. RESULTS: The average ADC value for protocol 1 for the cortex was 2.26 × 10(-3) mm(2)/s, for the medulla 2.21 × 10(-3) mm(2)/s. In protocol 2, the respective values were 2.13 × 10(-3) mm(2)/s and 2.06 × 10(-3) mm(2)/s. Neither statistically significant interobserver differences nor correlation between ADC values, GFR, and creatinine serum level were observed. CONCLUSION: The reference ADC values were established. The measurements show high interobserver consistency. The differences in ADC values reported in the literature suggest dependence on the equipment and methodology and point to the necessity of obtaining ADC norms for each MRI unit.

Do Anatomical Anomalies Affect the Results of Living Donor Kidney Transplantation?

BACKGROUND: Multiple renal artery kidneys still represent a special challenge for surgeons, during both nephrectomy for organ donation and transplantation. Recognition of anatomical conditions with advanced imaging methods is one of the most important elements of the preoperative evaluation process. AIM: The purpose of the current study was to assess if anatomical abnormalities affect the outcomes of living kidney donor transplantation procedures. PATIENTS AND METHODS: A retrospective analysis of 60 living kidney donors and their recipients was performed. Patients were assigned to two groups: pairs with a single allograft vessels (group I) and pairs with any anatomical abnormalities of the transplanted organ (group II). The impact of anatomical abnormalities on initial and long-term outcomes of the transplantation were analyzed. RESULTS: The analyzed study group consisted of 60 pairs (35 included in group I and 25 in group II). Immediate graft function was observed in 65.7% vs 64% individuals, recpectively (n.s.). Mean serum creatinine concentration was 1.6, 1.46, and 1.44 mg/mL (group I) vs 1.78, 1.78, and 1.65 mg/mL (group II) at 1, 6, and 12 months posttransplant, respectively (n.s.). Glomerular filtration rate (using the Chronic Kindey Disease Epidemiology Collaboration equation) was estimated at 54.3, 59.9, and 61.0 mL/min/1.73 m2 (group I) vs 59.8, 57.6, and 59.8 mL/min/1.73 m2 (group II) at the same time points, respectively (n.s.). CONCLUSIONS: Presence of single renal vessels was not a predictor of immediate graft function in living-donor kidney transplantation. Transplantation outcomes for kidneys with anatomical anomalies did not differ when compared to organs with typical anatomy. Multiple renal arteries did not impact initial graft function if precise surgical technique and proper preoperative diagnostics were provided.