Classification and therapeutic modalities of spinal vascular malformations in 80 patients

OBJECTIVE: To set up a more detailed classification system for spinal vascular malformations and to discuss the relationship between the classification and therapeutic alternatives. METHODS: Case series from the tertiary care center were studied. Spinal vascular malformations in 80 patients were reviewed and classified into intramedullary arteriovenous malformations (AVMs) (juvenile and glomus AVMs), intradural arteriovenous fistulas (AVFs) (Types I-III), dural AVFs, paravertebral AVMs, and Cobb's syndrome. Therapeutic alternatives to each type of spinal vascular malformations, including surgery, endovascular embolization, and a combination of both, as well as the short-term outcomes, were analyzed. RESULTS: Of the 80 patients, 38 (47.5%) had intramedullary AVMs (23 juvenile and 15 glomus AVMs), 27 (33.8%) had intradural AVFs (6 Type I, 14 Type II, and 7 Type III), 8 (10%) had dural AVFs, and 7 (8.8%) had other malformations. Most of the juvenile AVMs and the Types II and III AVFs were treated by endovascular embolization. Other lesions were treated by surgery or preoperative embolization plus surgery. Among the 76 patients whom we treated, early clinical improvement was achieved in 66 (86.8%). Six (7.9%) remained stable, and four (5.3%) became worse. CONCLUSION: Our classification system offers only limited guidance for the treatment of spinal vascular malformations. Successful treatment in each individual spinal vascular malformation requires correct understanding of the lesion's anatomic location and its angioarchitecture, as well as the limitations of both surgery and endovascular embolization.