Falciform ligament

Dural fold that covers the optic nerve at the optic canal.

The petrosphenoidal ligament (Gruber's ligament) extends from the petrous apex to the posterior clinoid process and forms the roof of Dorello's canal through which the abducens nerve passes. It forms the superior portion of the falciform ligament and is located at the confluence of the basilar plexus, cavernous sinus, inferior petrosal sinus, and sphenoparietal sinus. The petrolingual ligament forms the inferior portion of falciform ligament and covers the laceral segment of internal carotid artery. The length of the ligament has been reported to be between 13.2 and 13.9 mm in various studies.

Cutting the falciform ligament early decompresses the optic nerve, and helps minimize worsening of visual impairment from surgical manipulation in ophthalmic artery aneurysm treatment.

Takagi and Miyamoto, describe for the first time a case involving penetration of the optic nerve and falciform ligament. In addition, to remove the anterior clinoid process in this case, the ultrasonic bone curette was a useful tool¹⁾.

¹⁾

Takagi Y, Miyamoto S. Penetration of the optic nerve and falciform ligament byan internal carotid artery-ophthalmic artery aneurysm: case report. Neurol MedChir (Tokyo). 2014;54(3):211-3. Epub 2013 Oct 21. PubMed PMID: 24140766; PubMedCentral PMCID: PMC4533416.