Anatomical aspects in the transsphenoidal-transethmoidal approach to the optic canal: An anatomic-cadaveric study
Date
2012-10
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Churchill Livingstone
Abstract
Background: Determining anatomic landmarks during a transsphenoidal-transethmoidal approach to the optic canal region is of critical importance. Methods: Sella-parasella sphenoid bone blocks were extracted from adult cadavers. Anatomic dissections were performed in the optic canal region using a surgical microscope in 30 samples. Quantitative measurements were done using photographic techniques. For histological evaluation, coronal and longitudinal cross-sections were taken from the bilateral optic canal in seven decalcified samples. Results: Optic protuberance (OP), carotid protuberance (CP), medial opticocarotid recess (MOCR) and lateral opticocarotid recess (LOCR) were defined as lateral landmarks determining the width of the opening in the extended transsphenoidal-transethmoidal approach. Among all anatomic markers, LOCR was the most determinant lateral marker with tubercular recess the most prominent central marker. OPs showing the optic canal direction and inter-recessal sulci had similar distinguishing rates in the sphenoid sinus base. Inter-recessal sulci formed by OPs and CPs were observed between MOCR and LOCR in most samples. In histologic sections, the dural sheath was thicker inferolaterally to the optic nerve compared to superiorly and medially; collagen arrangement was dense and irregular. Conclusion: Although LOCRs and tubercular recesses are safe and prominent markers in extended transsphenoidaletransethmoidal approaches, other anatomic markers should also be taken into consideration to perform an efficient optic canal approach and optic canal decompression. Other factors for safe dissection are the length of the optic canal, bone thickness, adherence of dural structures and the course of the intradural ophthalmic artery.
Description
Keywords
Dentistry, oral surgery & medicine, Surgery, Optic canal, Optic nerve, Transsphenoidal-transethmoidal approach, Internal carotid artery, Tuberculum sellae meningiomas, Endoscopic endonasal approach, Nerve decompression, Skull base, Suprasellar craniopharyngiomas, Microsurgical anatomy, Transnasal approach, Technical note, Surgery, Resection
Citation
Yılmazlar, S. vd. (2012). "Anatomical aspects in the transsphenoidal-transethmoidal approach to the optic canal: An anatomic-cadaveric study". Journal of Cranio-Maxillofacial Surgery, 40(7), E198-E205.