Optic Canal Decompression: Comparison of 2 Surgical Techniques

World Neurosurg. 2017 Aug:104:745-751. doi: 10.1016/j.wneu.2017.04.171. Epub 2017 May 17.

Abstract

Background: The optic canal is a bony channel that connects the anterior cranial fossa and orbit and contains the optic nerve and ophthalmic artery. It can be affected by several pathologies, leading to compression of the nerve nearby or inside the canal, leading to visual impairment. The usual technique to decompress the canal is through a craniotomy, but recently endoscopic endonasal approaches (EEAs) have surfaced as an interesting alternative due to direct access to the canal without the need for manipulation of neurovascular structures.

Methods: Six specimens were dissected. The right optic canal was drilled on the right side via the EEA, and the left optic canal was drilled via frontotemporal craniotomy. The amount of decompression was measured using a 3-dimensional reconstruction on computed tomography scans and compared.

Results: The EEA generated an average of 267.8 (221-294) degrees of decompression in the anterior portion of the canal versus 258.3 (219-300) degrees of decompression in the posterior portion of the canal, whereas the craniotomy generated an average of 229.3 (101-289) degrees of decompression in the anterior portion of the canal versus 250.3 (76-300) degrees of decompression in the posterior portion of the canal. There was no significant difference statistically.

Conclusion: The decision for an approach for optic canal decompression should be based on the site of the pathology and localization of canal involvement. Both techniques are equivalent in terms of proportion of nerve decompression.

Keywords: Decompression; Endoscopic endonasal approach; Optic canal.

Publication types

  • Comparative Study

MeSH terms

  • Craniotomy / methods*
  • Decompression, Surgical / methods*
  • Dissection / methods
  • Endoscopy / methods*
  • Humans
  • Image Interpretation, Computer-Assisted
  • Imaging, Three-Dimensional
  • Nerve Compression Syndromes / diagnostic imaging
  • Nerve Compression Syndromes / surgery*
  • Ophthalmic Artery / diagnostic imaging
  • Ophthalmic Artery / surgery*
  • Optic Nerve Diseases / diagnostic imaging
  • Optic Nerve Diseases / surgery*
  • Outcome and Process Assessment, Health Care
  • Tomography, X-Ray Computed