Abstract No. 682 Updates for extremity arteriovenous malformations involving the bone: approach for embolization and its therapeutic outcomes

Abstract

To evaluate long-term data of the therapeutic outcomes, complications of embolotherapy retrospectively and establish therapeutic approach of embolotherapy of extremity arteriovenous malformations (AVMs) involving the bone. From December 1996 to July 2019, 36 patients (18 male, 18 female; mean age 25.1; age range, 1–64 years) with extremity AVMs involving the bone underwent staged embolotherapy using ethanol, coils and NBCA (n-butyl cyanoacrylate). Nineteen patients had pure bone AVMs and 17 had mixed bone and soft-tissue AVMs. Embolotherapy was performed by direct puncture, transvenous, and intraarterial approach (range, 1–18 procedures; mean, 4.9 procedures). Therapeutic outcomes were established by evaluation of the clinical response of symptoms and signs, as well as the degree of devascularization at follow-up angiography or computed tomography. Major and minor complications were also investigated during the follow-up at vascular malformation clinic. The clinical success (combined cure and markedly improvement outcomes) rate of embolotherapy of pure bone AVM was significantly better than that of mixed bone and soft tissue AVM (84.2% vs. 17.6%, P <0.001). Complete devascularization rate of bone AVM component of mixed bone and soft tissue AVM was 70.6%, but cure rate of mixed bone and soft tissue AVM was 0% because of skin and subcutaneous involvement of AVM. Twelve patients (11 minor; skin and transient peripheral nerve injury, 1 major; longstanding nerve palsy) experienced complications. The difference of complication rate between pure bone AVM and mixed bone and soft tissue AVM was not statistically significant (42.1% vs. 23.5%, P = 0.409). Embolotherapy of extremity AVMs involving the bone is effective and safe treatment to eliminate or improve symptoms with long-term follow-up data, especially in pure bone AVM.