Posterior petroclinoid fold
Plica petroclinoidea posterior
Definition
The posterior petroclinoid fold arises from the posteromedial extension of the attached tentorium cerebelli and connects the posterior clinoid process with the anterior petrous ridge. It forms the medial border of the oculomotor trigone, the roof of the porus trigeminus (the entrance to Meckel cave), and the roof of the petroclival venous confluence.
It lies in close proximity to the oculomotor nerve that crosses it.
The posterior petroclinoid dural fold may completely ossify and form a bar of bone spanning the roof of the porus trigeminus, that may lead to narrowing of the porus trigeminus. The completely ossified posterior petroclinoid dural fold is called the “petroclinoid bone”.
The posterior petroclinoid fold should not be confused with the petroclinoid ligament
References
Text by Antoine Micheau, MD - Copyright IMAIOS
Gutierrez S, Khan PA, Iwanaga J, Dumont AS, Tubbs RS. Review of the Petroclinoid Ligament. Kurume Med J. 2022 Mar 11;67(1):5-10. doi: 10.2739/kurumemedj.MS671007. Epub 2022 Jan 31. PMID: 35095019.
Iwanaga, Joe; Altafulla, Juan J.; Gutierrez, Santiago; Dupont, Graham; Watanabe, Koichi; Litvack, Zachary; Tubbs, R. Shane . (2019). The Petroclinoid Ligament: Its Morphometrics, Relationships, Variations, and Suggestion for New Terminology. Journal of Neurological Surgery Part B: Skull Base, (), s-0039-1692699–. doi:10.1055/s-0039-169269.
Wysiadecki G, Haładaj R, Polguj M, Żytkowski A, Topol M. Bilateral Extensive Ossification of the Posterior Petroclinoid Ligament: An Anatomical Case Report and Literature Review. J Neurol Surg A Cent Eur Neurosurg. 2019 Mar;80(2):122-126. doi: 10.1055/s-0038-1666782. Epub 2018 Jul 30. PMID: 30060260.
