Purpose: The aim of this study was to evaluate the different MRI diagnoses in the early and late post-operative period after renal transplantation with dysfunctional allograft.
Materials and methods: Due to unknown transplant dysfunction, 49 patients (30-male, 19 female) received a total of 74 MRI studies. According to the date of examination all MRI studies were divided in an early (< or = 60 days, ETP) and a late post-transplant time period (> 60 days, LTP). All MRI studies were performed on 1.5 T MRI systems using a standardised imaging protocol consisting of a morphological (pre- and post-contrast enhanced T (1)- and T (2)-weighted TSE sequences), a vascular (contrast-enhanced 3D MRA) and a urographical part (Flash 3D sequences). Frequencies of diagnoses in ETP and LTP, and diagnoses within each transplant time period were analysed.
Results: 44/74 MRI studies were performed in ETP, 30/74 in LTP. In total 80 diagnoses were obtained: Renal artery stenosis (ETP, n = 21; LTP, n = 5), renal vein stenosis (ETP, n = 2), renal vein thrombosis (ETP, n = 2), renal perfusion defect (ETP, n = 11), rejection (ETP, n = 1; LTP, n = 2), abscess (ETP, n = 1), urinary outflow obstruction (LTP, n = 4), without MRI pathology (ETP, n = 11; LTP, n = 20). Renal artery stenosis was the most prevalent diagnosis in ETP, and a more frequent finding in ETP compared to LTP (p < 0.05). Renal perfusion defects were more frequent in ETP than in LTP (p < 0.05). In the ETP vascular diseases (34/49 diagnoses) were more frequent (p < 0.05) than uropathological diseases (0/49 diagnoses).
Conclusions: Our results indicate that vascular diseases are a more frequent occurrence in the early post-operative course after renal transplantation than uropathological diseases. However, a transplant follow-up MRI study needs to contain a morphological, vascular and functional imaging part to answer combined clinical questions.