A study on anterior clinoid process and optic strut with emphasis on variations of caroticoclinoid foramen.

This study presents the incidence of carotico-clinoid foramen, dimensions of the anterior clinoid process and optic strut in dry skulls to provide a guide to neurosurgeons in surgical approach especially to anterior part of cavernous sinus. Thirty-five dry skulls were used. Basal width, length, thickness of anterior clinoid process and thickness of optic strut was measured. Morphology of carotico-clinoid foramen was also studied. The average length, basal width and thickness of the anterior clinoid process on right side were 10.74 +/- 2.37 mm, 10.83 +/- 1.20 mm, 5.13 +/- 1.03 mm and left side were 9.91 +/- 1.50 mm, 11.0 +/- 1.12, 5.33 +/- 0.96 mm. Average thickness of optic strut was 3.79 +/- 0.88 mm on right side and 3.61 +/- 0.78 mm on left side. Out of 70 sides in thirty five skulls examined, carotico-clinoid foramen was observed in 14 (20.0%) cases. Out of which complete foramen was in 3 (right side, 4.3%), partial in 8 (6 right, 2 left, 11.4%) and contact in 3 (left side, 4.3%) respectively. Comparison with other races and differences between right and left sides were also discussed. The present study was done to obtain dimensions of anterior clinoid, optic strut, their anatomical variants and incidence of caroticoclinoid foramen in location population. This study will help the surgeons to plan their approach to this area and thus will make the surgical procedure safer