Intraoperative direct venous puncture and embolization for arteriovenous shunt below the conus medullaris: a prospective cohort study

Abstract

BackgroundArteriovenous shunt below the conus medullaris (AVS-BC) is easily misdiagnosed and mistreated due to its rarity. Achieving an anatomical cure solely through endovascular or surgical means is challenging. This study aimed to summarize the clinical and radiological features of AVS-BC and evaluate the safety and efficacy of hybrid techniques represented by intraoperative direct venous puncture and embolization (IVPE).MethodsThe patients with AVS-BC were grouped into those with dural, intradural, and paravertebral shunts. The patients undergoing hybrid procedures were consecutively recruited between August 2016 and July 2022. The modified Aminoff and Logue’s Scale (mALS) and the modified Denis Pain and Numbness Scale (mDS) were used to evaluate motor and sensation disturbances.ResultsA total of 42 patients (35 males, 83.3%) were included with an average age of 57.38±10.79 years. Most patients presented with lower limb weakness and sphincter disturbances. Their preoperative average mALS score was 7.17±2.61 and the preoperative average mDS score was 3.88±1.76. There were 28 patients (66.7%) who received IVPE. The mean clinical follow-up reached 41.30±21.10 months. All patients achieved anatomical cures without permanent neurological complications. It showed a significant improvement in mALS scores after the intervention in the spinal dural arteriovenous fistula only (P=0.026). No recurrences were reported.ConclusionsDifferentiating AVS-BC mainly relied on identifying supplying arteries, shunt placements, and draining veins. The hybrid technique typified by IVPE conferred a safe anatomical cure for AVS-BC.