Korean J Transplant.  2022 Nov;36(Supple 1):S310. 10.4285/ATW2022.F-4501.

The usefulness of contrast enhanced magnetic resonance angiography in the early period after renal transplantation

• Hwang JK
• Cho HJ
• Kim MH
• Ban TH
• Lee JM
• Jeon Ch
• Choi BS
• Park MK
• Lim JH

• KMID: 2535537
• DOI: http://doi.org/10.4285/ATW2022.F-4501

Abstract

Background
Our objective was to evaluate the usefulness of three-dimensional contrast enhanced magnetic resonance angiography (3D CE-MRA) for assessment of renal parenchyma itself, arterial inflow stenosis, and peritransplant fluid collection in the early period after renal transplantation.
Methods
Between April 2019 and July 2022, a consecutive series of 62 renal transplants was examined with 3D CE-MRA 14 days after transplantation. MRA studies were analyzed for the volume of renal parenchyma, presence of arterial stenosis, renal infarction, and peritransplant fluid collection. The degree of renal transplant artery inflow stenosis was graded qualitatively as <50%, mild; 50%–70%, moderate; >70%, severe.
Results
Kidney volume, measured with MRA, varied from 148 to 421 (226.146.8 mL). It is higher than that of preoperation CT volume (171.132.8) (P<0.005). Twenty (31.3%) of the 64 patients had normal CE-MRA which were no parenchymal infarction, no fluid collection and no arterial inflow stenosis. MRA showed parenchyma infarction (n=8, 12.5%), arterial inflow stenosis (n=17, 26.6%), lymphocele (n=22, 34.4%) and hematoma (n=3, 4.7%). Among the patients with arterial inflow stenosis, 16 (25.0%) showed mild, 1 patient (1.6%) moderate, and no severe stenosis. The patient with moderate arterial stenosis on CE-MRA un-derwent selective digital subtraction angiography; PTA with stent was performed successfully. The mean creatinine level at 1 month, 6 months, and 1 year after transplantation were not significantly different in patients with arterial stenosis from those of others (P=0.379, P=0.359, and P=0.136).
Conclusions
The incidence of renal parenchyma infarction, peritransplant fluid collection and arterial flow stenosis is unexpectedly high in the early period after kidney transplantation. MRA and MR imaging allows rapid global assessment of renal parenchyma, renal transplant arterial system, and peritransplant fluid collection. It can also help detect or exclude many of the various causes of renal transplant dysfunction.