Ioku Tetsuya, Ohshima Tomotaka, Yokota Mao, Matsuo Naoki, Miyachi Shigeru
Stroke Center, Aichi Medical University, Nagakute, Japan.
Neuroendovascular Therapy Center, Aichi Medical University, Nagakute, Japan.
Neurointervention. 2023 Nov;18(3):190-194. doi: 10.5469/neuroint.2023.00185. Epub 2023 Jul 26.
Transarterial embolization using Onyx is a well-established treatment for dural arteriovenous fistulas (DAVFs). However, complications can arise when Onyx migrates into the venous side, impairing the draining veins. We encountered a case where Onyx, injected through the arterial side, strayed into the jugular vein, forming a hairball-like structure. Our study aimed to investigate the underlying mechanism of this unusual phenomenon. We postulated that Onyx precipitates into thread-like shapes when passing through extremely narrow openings. To test this, we extruded Onyx from a syringe through a 27-gauge needle into a silicone tube with flowing water. By varying the flow speed, we observed the hardening behavior of Onyx. Under slow flow, the extruded Onyx quickly solidified at the needle tip, forming a round mass. Conversely, high-speed flow resulted in Onyx being dispersed as small pieces. We successfully replicated the formation of "Onyx threads" under continuous slow flow conditions, similar to our case. This phenomenon occurs when Onyx unexpectedly migrates to the draining vein through a tiny opening during transarterial embolization for arteriovenous shunt diseases. Early recognition and appropriate measures are necessary to prevent occlusive complications in the draining veins and the pulmonary system.
使用Onyx进行经动脉栓塞是治疗硬脑膜动静脉瘘（DAVF）的一种成熟方法。然而，当Onyx迁移到静脉侧时，可能会出现并发症，损害引流静脉。我们遇到了一例通过动脉侧注入的Onyx误入颈静脉并形成毛球状结构的病例。我们的研究旨在探讨这一异常现象的潜在机制。我们推测，Onyx在通过极窄开口时会沉淀成线状。为了验证这一点，我们将Onyx从注射器中通过27号针头挤出到有流水的硅胶管中。通过改变流速，我们观察了Onyx的硬化行为。在缓慢流动的情况下，挤出的Onyx在针尖迅速凝固，形成一个圆形团块。相反，高速流动会导致Onyx分散成小碎片。我们在持续缓慢流动的条件下成功复制了“Onyx线”的形成，类似于我们的病例。这种现象发生在经动脉栓塞治疗动静脉分流疾病时，Onyx意外地通过一个微小开口迁移到引流静脉。早期识别和采取适当措施对于预防引流静脉和肺部系统的闭塞性并发症是必要的。
