Determination of Duplicated Optic Canals in Eastern Indian Human Skulls from India

The duplication of optic canals is a rare anomaly found in both sexes, all ages and various races.

Objective: The present study was carried out to find the incidence of duplication of optic canal and study its clinical and developmental significance.

Methods: The study included 100 dry human skulls of both the sexes and various age groups. These skulls were studied grossly and morphologically to find out duplication of the optic canals.

Results: Additional optic canals were found in 3 skulls (3% cases). Out of them 2 cases (2%) presented bilateral duplication whereas in only one case (1%) it was unilateral. The larger main canal was in the usual position directed posteromedially upwards and was continuous with the anterolateral end of Sulcus chiasmaticus. The smaller or duplicated canal was inferolateral to the main canal in the lesser wing of sphenoid. The main and accessory canals were separated by bony septa.

Conclusion: Knowledge of additional optic canals is of paramount importance in performing surgical exploration of optic canal during removal of tumours or decompression of optic canals or surgically accessing the cavernous sinus or Sella turcica.