A clinical and neuropathologic study of silk suture as an embolic agent for brain arteriovenous malformations.

PURPOSE To evaluate the safety and efficacy of silk suture as an agent for preoperative embolization of cerebral arteriovenous malformations. METHODS Clinical and histopathologic results were analyzed in six patients who underwent embolization of cerebral arteriovenous malformations using silk suture in combination with other agents. RESULTS Three of the patients treated with silk hemorrhaged after embolization, and two of these patients died. Neuropathologic analysis of four patients showed acute perivascular inflammation, sometimes quite severe. CONCLUSIONS The inflammatory response to silk may explain its effectiveness in producing vascular occlusion. However, a fulminate vasculitis theoretically can predispose to delayed hemorrhage. Other problems with silk include the pressure required to inject the agent and the inability to determine the final site of deposition of the silk. Although other embolic agents may share some of these potential difficulties, we feel that the disadvantages outweigh the advantages of silk as an embolic agent.