Spittau Björn, Millán Diego San, El-Sherifi Saad, Hader Claudia, Singh Tejinder Pal, Motschall Edith, Vach Werner, Urbach Horst, Meckel Stephan
Institute for Anatomy and Cell Biology, Department of Molecular Embryology, Albert-Ludwigs-University Freiburg;
J Neurosurg. 2015 Apr;122(4):883-903. doi: 10.3171/2014.10.JNS14377. Epub 2014 Nov 21.
Dural arteriovenous fistulas (DAVFs) of the hypoglossal canal (HCDAVFs) are rare and display a complex angiographic anatomy. Hitherto, they have been referred to as various entities (for example, "marginal sinus DAVFs") solely described in case reports or small series. In this in-depth review of HCDAVF, the authors describe clinical and imaging findings, as well as treatment strategies and subsequent outcomes, based on a systematic literature review supplemented by their own cases (120 cases total). Further, the involved craniocervical venous anatomy with variable venous anastomoses is summarized. Hypoglossal canal DAVFs consist of a fistulous pouch involving the anterior condylar confluence and/or anterior condylar vein with a variable intraosseous component. Three major types of venous drainage are associated with distinct clinical patterns: Type 1, with anterograde drainage (62.5%), mostly presents with pulsatile tinnitus; Type 2, with retrograde drainage to the cavernous sinus and/or orbital veins (23.3%), is associated with ocular symptoms and may mimic cavernous sinus DAVF; and Type 3, with cortical and/or perimedullary drainage (14.2%), presents with either hemorrhage or cervical myelopathy. For Types 1 and 2 HCDAVF, transvenous embolization demonstrates high safety and efficacy (2.9% morbidity, 92.7% total occlusion). Understanding the complex venous anatomy is crucial for planning alternative approaches if standard transjugular access is impossible. Transarterial embolization or surgical disconnection (morbidity 13.3%-16.7%) should be reserved for Type 3 HCDAVFs or lesions with poor venous access. A conservative strategy could be appropriate in Type 1 HCDAVF for which spontaneous regression (5.8%) may be observed.
舌下神经管硬脑膜动静脉瘘（HCDAVF）较为罕见，血管造影显示其解剖结构复杂。迄今为止，它们仅在病例报告或小样本系列中被描述为各种不同的类型（例如，“边缘窦DAVF”）。在对HCDAVF的深入综述中，作者基于系统的文献回顾并结合自身病例（共120例），描述了临床和影像学表现、治疗策略及后续结果。此外，还总结了涉及颅颈静脉的解剖结构及可变的静脉吻合情况。舌下神经管DAVF由一个瘘性囊袋组成，累及髁前汇合处和/或髁前静脉，并伴有可变的骨内成分。三种主要的静脉引流类型与不同的临床模式相关：1型，顺行引流（62.5%），主要表现为搏动性耳鸣；2型，逆行引流至海绵窦和/或眶静脉（23.3%），与眼部症状相关，可能类似海绵窦DAVF；3型，皮质和/或髓周引流（14.2%），表现为出血或颈髓病。对于1型和2型HCDAVF，经静脉栓塞显示出高安全性和有效性（发病率2.9%，完全闭塞率92.7%）。如果无法进行标准的经颈静脉入路，了解复杂的静脉解剖结构对于规划替代方法至关重要。经动脉栓塞或手术切断（发病率13.3%-16.7%）应保留用于3型HCDAVF或静脉入路不佳的病变。对于1型HCDAVF，保守策略可能是合适的，因为可能会观察到自发消退（5.8%）。
