The Anatomical Landmarks in Endonasal Endoscopic Optic Nerve Decompression Surgery: An Anatomical Study

Aim Optic nerve decompression can be applied for many pathologies that affect the optic canal and the optic nerve. Optic nerve decompression via endonasal endoscopic method is very popular in nowadays with the developments in endoscopic surgery. Material and Methods In this study, the lateral opticocarotid recess (LOCR) and the medial opticocarotid recess (MOCR) which are important anatomical landmarks used during transsphenoidal approach to the opticocarotid region were evaluated. The relations of these anatomical landmarks with each other and with important surrounding landmarks such as optic nerve were examined. Results MOCR were observed in all cadavers on the right side and in 4 of 5 cadavers on the left side. The superior border of the LOCR was measured as 4.85±1.94 mm in average on the right side and 3.93±1.11 mm in average on the left side. The inferior border of the LOCR was measured as 4.72±2.11 mm in average on the right side and 3.98±1.67 mm in average on the left side. The linear distance between the LOCR and the MOCR was measured as 3.11±1.41 mm in average on the right side and 2.46±1.36 mm in average on the left side. Conclusion It is necessary for a safe surgery to reveal the anatomical landmarks and to know the detailed anatomy of this region during optic nerve decompression.