Anatomical insights: meningo-orbital foramen and its clinical relevance

The meningo-orbital foramen (MOF) is an inconsistently present bony canal that connects the orbit with the cranial cavity, commonly the middle cranial fossa. It may transmit the meningolacrimal artery supplying orbital contents, making it clinically relevant in procedures involving the lateral orbital wall. This study aimed to investigate the morphometry and anatomical positioning of the MOF and discuss its surgical implications.

A total of 127 adult dry human skulls (254 orbits) were examined. Gender was estimated morphometrically, while ethnicity was unknown. The incidence, laterality and connection patterns of the MOF were evaluated. Additionally, the distance between the MOF and the frontozygomatic suture (FZS) was measured.

Patent MOF was identified in 51.2% of skulls (65/127), with bilateral presence in 41.5% of those. By orbit count, the incidence was 36.2%. Accessory MOFs were found in 3% of orbits, including seven cases with two and one case with three foramina. Nearly half of the MOFs were located in the greater wing of the sphenoid, and over 95% communicated with the middle cranial fossa. The mean MOF-FZS distance on the left side was significantly greater in males (p=0.02), while the right side showed no significant gender difference.

MOF has high surgical relevance due to its frequency and association with critical vascular structures. Precise morphometric knowledge can help minimise intraoperative risk. Further cadaveric investigation is suggested to investigate the course of the meningolacrimal artery and improve surgical outcomes.