Diego San Millán Ruíz and Dheeraj Gandhi
Anshuman Bansal, Philippe Gailloud, Lori Jordan and Diego San Millán Ruíz
The authors present the case of an infant harboring a vein of Galen arteriovenous malformation with conspicuous cerebral calcifications that progressively regressed after staged endovascular obliteration of the lesion. The role of venous hypertension and hydrocephalus secondary to the arteriovenous shunt are discussed to explain the formation and regression of the cerebral calcifications.
Björn Spittau, Diego San Millán, Saad El-Sherifi, Claudia Hader, Tejinder Pal Singh, Edith Motschall, Werner Vach, Horst Urbach and Stephan Meckel
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.