404 Anatomy of the Dorsal Meningeal Artery Including its Variations: Application to Skull Base Surgery and Diagnostic and Interventional Imaging

Abstract

INTRODUCTION: The skull base vasculature is critical to surgeons operating in this region. However, one vessel with a vast skull base distribution, the dorsal meningeal artery (DMA), has had few anatomical studies performed to investigate not only its normal anatomy but also its variations. METHODS: In ten adult latex-injected cadaveric heads (twenty sides), the DMA was dissected using a surgical microscope and its branches were measured. RESULTS: A DMA was identified on all sides. In most (85%), it branched from the meningohypophysial trunk or common stem with either the inferior hypophysial or tentorial arteries and on three sides (15%), arose as a separate branch from the internal carotid artery. Within Dorello’s canal, the DMA was the most medial structure with the abducens nerve and the inferior petrosal sinus found laterally in most specimens. On one side (5%), the artery had two branches that traveled on either side of the abducens nerve distal to the petroclival ligament. Toward the midline, many (70%) of the clival branches pierced the clivus. Most (80%) clival branches anastomosed with their counterparts contralaterally and all traveled deep to the abducens nerve. Dural branches were found traveling to the clival dura and to the dura forming Meckel’s cave. Neural branches were identified traveling to the abducens and hypoglossal nerves. In two sides (10%), the DMA provided an ascending branch to the posterior pituitary gland. On 15% of sides, vascular branches traveled to the adventitia of the cavernous internal carotid artery and most sides (80%) had a descending branch to the inferior petrosal sinus which then anastomosed with jugular branches of the ascending pharyngeal artery. CONCLUSION: The DMA is a constant, although variable, vascular structure of the skull base and contributes to multiple structures in addition to the dura.