Microsurgical anatomy of the dural arteries.

OBJECTIVE: The objective was to examine the microsurgical anatomy basic to the microsurgical and endovascular management of lesions involving the dural arteries.
METHODS: Adult cadaveric heads and skulls were examined using the magnification provided by the surgical microscope to define the origin, course, and distribution of the individual dural arteries.
RESULTS: The pattern of arterial supply of the dura covering the cranial base is more complex than over the cerebral convexity. The internal carotid system supplies the midline dura of the anterior and middle fossae and the anterior limit of the posterior fossa; the external carotid system supplies the lateral segment of the three cranial fossae; and the vertebrobasilar system supplies the midline structures of the posterior fossa and the area of the foramen magnum. Dural territories often have overlapping supply from several sources. Areas supplied from several overlapping sources are the parasellar dura, tentorium, and falx. The tentorium and falx also receive a contribution from the cerebral arteries, making these structures an anastomotic pathway between the dural and parenchymal arteries. A reciprocal relationship, in which the territories of one artery expand if the adjacent arteries are small, is common.
CONCLUSION: The carotid and vertebrobasilar arterial systems give rise to multiple branches that supply the dura in a complex and overlapping pattern. A knowledge of the microsurgical anatomy of these dural arteries and their assessment on pretreatment evaluations plays a major role in safe and accurate treatment of multiple lesions.