外傷性椎骨動静脈瘻に対してinternal trappingで治療した1例

A Case of Traumatic Vertebral Arteriovenous Fistula Treated by Internal Trapping of the Vertebral Artery

Ⅰ．はじめに

　外傷性椎骨動静脈瘻（traumatic vertebral arteriovenous fistula：TVAVF）は稀な疾患であり，外傷に起因して椎骨動脈（vertebral artery：VA）と周囲静脈叢との間にfistulaを形成する疾患である¹²⁾．TVAVFは穿通性頚部外傷，頚椎骨折，スクリューによる頚椎固定手術に伴う合併症などで起こると報告されている⁴⁾．約30%は無症候性であり¹⁾，頚部の雑音などで発見されることが多い．今回，頚椎骨折に伴うTVAVFに対して血管内治療によるinternal trappingが有効であった症例を経験したので報告する．

　Background:Traumatic vertebral arteriovenous fistula（TVAVF）is an uncommon disease that occurs after traumatic injury. Here we report a case of TVAVF presenting with cervical bruit successfully treated by internal trapping using coils.

　Case Presentation:A 66-year-old man was transferred to our hospital after falling into a ditch. Initial CT revealed a C2 fracture into the right transverse foramen, and the patient had been treated with conservative management. A vascular abnormality was suspected because the patient exhibited cervical bruit on admission. CT angiography revealed right TVAVF at the V2 segment of the right vertebral artery（VA）near the C2 fracture. Digital subtraction angiography also revealed right TVAVF between the V2 segment of the right VA and the vertebral venous plexus, draining into the right internal jugular vein and the deep cervical vein as well as the intracranial venous system. The fistula was also opacified by retrograde flow from the contralateral VA through the union, while the flow in the basilar artery was antegrade.

　The patient was diagnosed with TVAVF with large transection of the right VA, and underwent endovascular treatment with internal trapping of the right VA using coils starting distal to the transection and proceeding in a proximal direction. After treatment, the right VAVF and right VA were completely occluded. The patient achieved clinical symptom resolution with no neurological deficits.

　Conclusion:Endovascular treatment with internal trapping of the VA using coils is safe and effective against TVAVF.