Evaluation of Magnetic Resonance Vascular Wall Imaging (VW-MRI) in Assessing the Vessels of Upper Limb Autologous Arteriovenous Fistulas in Hemodialysis Patients

doi:10.16458/j.cnki.1007-0893.2025.15.020

Abstract：Objective: To explore the value of magnetic resonance vascular wall imaging (VW-MRI) in assessing the vessels of upper limb autologous arteriovenous fistulas (AVF) in hemodialysis patients. Methods: A prospective study was conducted on 20 patients with end-stage renal failure who underwent maintenance hemodialysis at the Department of Nephrology, Affiliated Dongguan First Hospital of Guangdong Medical University from October 2021 to December 2022. The AVF sites were scanned using MR TOF3D-TRA-UCS or TOF2D-MRV, T1-MX3D-SAG-FS, T1-MX3D-COR-FS, and T2-MX3D-SAG-FS sequences. Image quality of the瘘口 segment, inflow arterial segment, and outflow venous segment of the AVF was evaluated on each sequence of vascular wall imaging, as well as on MRA and MRV images. Inter-observer consistency was analyzed, and the lumen diameter and vessel wall thickness of each segment were assessed, along with the presence of complications. Results: There was good inter-observer consistency for all segments of the AVF (fistula segment, inflow arterial segment, outflow venous segment) on VW-MRI [Intraclass Correlation Coefficient (ICC) values were all >0.75, P < 0.05]. The image quality on VW-MRI was higher than that on MRA and MRV. On VW-MRI, the image quality of the fistula segment and inflow arterial segment was higher than that of the outflow venous segment, while on MRA and MRV, the image quality of the fistula segment was lower than that of the inflow arterial and outflow venous segments, with statistically significant differences (P < 0.05). VW-MRI could clearly display the lumen diameter and vessel wall thickness of each segment of the AVF. Among them, one case showed localized stenosis and thrombosis at the fistula segment; two cases showed localized stenosis at the fistula segment; two cases showed segmental stenosis at both the fistula segment and outflow venous segment; one case showed irregular bead-like stenosis at the fistula segment and localized stenosis with fusiform dilation at the outflow segment; three cases showed local narrowing of the outflow venous segment, five cases showed segmental stenosis, and one case showed irregular bead-like stenosis. Six cases showed thickening of the vessel wall at the fistula segment, and 14 cases showed thickening of the vessel wall at the outflow venous segment. One case showed local weakness of the vessel wall at the outflow venous segment. Conclusion: VW-MRI combined with MRA and MRV can clearly display and evaluate the morphology, lumen, vessel wall, and presence of complications in each segment of the AVF. It can provide direct imaging and diagnostic evaluation of thrombosis without contrast agents, and is expected to become a safe, effective, and widely applicable clinical examination method for AVF.