Utility of T2-weighted MRI and contrast-enhanced MRA in locating the fistula level of spinal arteriovenous fistula.

Objective: To investigate the value of routine T2-weighted magnetic resonance imaging (MRI) and contrast-enhanced magnetic resonance angiography (CE-MRA) sequences in locating the fistula level of spinal arteriovenous fistula (SAVF).

Methods: Retrospectively analyzed the radiological findings of patients with SAVF diagnosed by surgery from May 2018 to September 2024. All patients completed spinal CE-MRA and routine T2-weighted MRI. The imaging manifestations of SAVF lesions on CE-MRA and MRI were summarized and analyzed.

Results: We enrolled 40 cases with SAVF (average age 58.1 years old, 85.0% male). The majority of fistulas were located in the thoracic (60.0%), followed by the lumbar (27.5%), and cervical (12.5%). Based on CE-MRA images, the fistula of 33 cases (82.5%) with SAVF can be accurately located, the perimedullary varicose vessels of 34 cases (89.47%) can be shown, and the feeding arteries of 27 cases (71.05%) can be identified. Based on T2-weighted MRI, the perimedullary flow voids and T2 hyperintensity were seen in 36 (90.0%) of SAVF cases, the fistula level in 88.9% (32/36) of cases was located at one end of the flow voids within 1 vertebral level, and the flow voids of 72.2% (26/36) cases near the fistula to be more tension. There is no significant difference in the accuracy of routine T2-weighted MRI in locating the fistula level compared to CE-MRA and digital subtraction angiography (DSA).

Conclusion: Both routine T2-weighted MRI and CE-MRA sequences are valuable in the detection of SAVF fistula, we can locate the fistula level by the clues of the perimedullary varicose vessels.