Rare Bony Tunnel and the Middle Meningeal Artery

Abstract

The middle meningeal artery is predominantly periosteal, irrigating the bone and dura mater. It enters the floor of the middle cranial fossa through the foramen spinosum, travels laterally through a middle fossa bony ridge, and curves anteriorly over the upper‐greater wing of the sphenoid where, at a variable point, it divides into parietal and frontal branches. The proximal segment of the frontal branch can be located in a bony tunnel and thus be particularly susceptible to tearing when the skull fractures. In addition, occasionally, the distal segment of the frontal branch may traverse a bony tunnel of variable size. To the best of our knowledge, there is no evidence in the current literature on the incidence of this rare bony tunnel. Thus, we decided to investigate the incidence of this bony tunnel in 85 adult skulls. In the studied sample, a significant tendency for this bony tunnel to be formed on the left side (p = 0.016). This paper also deals with some embryological aspects that may contribute towards explaining the formation of this bony tunnel.