Accurate course and relationships of the intraorbital part of the ophthalmic artery in the sagittal plane

Introduction: Knowledge of variations in the course and distribution of the intraorbital part of ophthalmic artery (OA) is necessary for the diagnosis and treatment of anterior cranial and orbital disorders. Material: 38 human cadaver dissections to demonstrate the microsurgical anatomy of the intraorbital part of the OA were studied in three stages, considering its neighbourhood with the optic nerve in the sagittal plane. Results: The first part of the OA was located on the inferolateral aspect of the optic nerve in 89.47%. The diameter and the length of the first part of the OA were 1.69 +/- 0.34 mm and 7.58 +/- 0.89mm. 73.68% of the cases crossed the optic nerve superiorly, and 26.31 % inferiorly. The diameter and length of the second part of the OA were as 1.52 +/- 0.29mm and 4.12 +/- 0.85 mm. The diameter and length of the third part of the OA were 1.07 +/- 0.18 mm and 4.12 +/- 0.85 mm. The first branch of the intraorbital part of the OA was the central retinal artery in 26.31 % of the specimens. Conclusion: A better understanding of the vascular anatomy of the orbit should allow for the modification of surgical techniques to reduce bleeding during biopsy or excision of orbital structures.