A Rare Case of Subarachnoid Hemorrhage caused by Ruptured Venous Varix Due to Dural Arteriovenous Fistula at the Foramen Magnum Fed Solely by the Ascending Pharyngeal Artery

Dural arteriovenous fistula (D-AVF) at the foramen magnum is an extremely rare disease entity. It produces venous hypertension, and can lead to progressive cervical myelopathy thereafter. On the other hand, the venous hypertension may lead to formation of a venous varix, and it can rarely result in an abrupt onset of subarachnoid hemorrhage (SAH) when the venous varix is ruptured. The diagnosis of D-AVF at the foramen magnum as a cause of SAH may be difficult due to its low incidence. Furthermore, when the D-AVF is fed solely by the ascending pharyngeal artery (APA), it may be missed if the external carotid angiography is not performed. The outcome could be fatal if the fistula is unrecognized. Herein, we report on a rare case of SAH caused by ruptured venous varix due to D-AVF at the foramen magnum fed solely by the APA. A review of relevant literatures is provided, and the treatment modalities and outcomes are also discussed.

Morphological observation of Ascending Pharyngeal Artery and Ascending Palatine Artery / 昆明医科大学学报

A detailed description of the ascending pharyngeal artery and the ascending palatine artery,including their courses,branches and supplies,was given based on the full dissection,exposure and comparison of 30 sides of half-head specimens(20 sides of fetus heads and 10 sides of adult heads).The results are as follows:(1) the arteries can be divided into three types,the dominant type of the ascending pharyngeaL artery,the dominant type of the ascending palatine artery and the type of balance;(2)the various branches of the ascending pharyngeal artery,especia- lly some branches unknown or known a little,have been described in detail;(3) recommendation of a simple and rapid method for exposing these two arteries.