Post Renal Transplant Surgical Complications; MRI Standard Applications and Diagnostic Outcomes

Abstract

Objective: Fast MR imaging sequences together with paramagnetic contrast agents, offer multiple advantages in the assessment of renal function. It provides cross sectional and vascular information without the risk of ionizing radiation, iodinated contrast or arterial catheterization. Post transplantation complications can be grouped as surgical or medical. Immediate surgical complications include renal artery thrombosis or stenosis, urinary leak or lymphocele. Renal allograft frequently require repeated imaging studies during the immediate post-operative period and various times thereafter, when renal function is compromised. Background: End stage renal disease is common and can result from a variety of diseases. Kidney transplantation from living-related donors offered the best prognosis. Imaging modalities that are currently used to evaluate transplanted kidneys are ultrasound (US), computed tomography (CT), scintigraphy, intravenous urography (IVU), contrast angiography, and magnetic resonance imaging (MRI). Methods: This study was conducted on 181 renal transplant recipients. Recipients were 139 males and 42 females. Their age ranged from 20 to 58 years (mean age 39 years). The patients underwent clinical assessment, Laboratory investigations, and different Radiological imaging procedures as: I- Gray scale and color Doppler ultrasonography. II- Magnetic Resonance Imaging. 3D Gd-enhanced MRA. MR Urography. Selective IA-DSA of the graft artery. III- Percutaneous catheter nephrostomy (PCN) and antegrade pyelography. IV- Radio-isotope diuretic renogram using 99m Tc-MAG3. Results: 30 renal transplants were examined by MRI in the 1st 2 weeks after renal transplantation. At the end of 1st 2 weeks, MR examinations were carried out, as basal studies (including MRI, MRA and MRU) for 98 transplants. From this group, 64 transplants were subjected to other MR examinations. After the 1st 2 weeks, 53 transplants were subjected to MR examinations for the 1st time at variable post-transplant duration. Among the studied 181 renal transplants, MR examinations detected 3 cases with graft arteries thrombosis (1.6%), 10 with graft arteries stenosis (5.5%), 6 with segmental infarctions (3.3%), 3 cases with graft intrarenal arteries pseudo-aneurysms (1.6%) and 2 cases with arterio- venous fistulae (1.1%) after graft biopsies. Conclusion: MRI is highly recommended to evaluate intra-/extra-renal graft vascular lesions, urinary obstructive syndrome, compressive collections (urinoma, lymphocele), inflammatory and tumoral lesions of the renal graft.