title: Ossification of the Posterior Petroclinoid Dural Fold: A Cadaveric Study with Neurosurgical Significance.
abstract: Objectives The roof of the porus trigeminus, composed of the posterior petroclinoid dural fold, is an important landmark to the skull base surgeon. Ossification of the posterior petroclinoid dural fold is an anatomical variation rarely mentioned in the literature. Such ossification results in the trigeminal nerve traversing a bony foramen as it enters Meckel cave. The authors performed this study to better elucidate this anatomical variation. Design Fifteen adult cadaveric head halves were subjected to dissection of the middle cranial fossa. Microdissection techniques were used to examine the posterior petroclinoid dural folds. Skull base osteology was also studied in 71 dry human skulls with attention paid to the attachment point of the posterior petroclinoid dural folds at the trigeminal protuberances. Setting Cadaver laboratory Main Outcome Measures Measurements were made using a microcaliper. Digital images were made of the dissections. Results Completely ossified posterior petroclinoid folds were present in 20% of the specimens. Of the 142 dry skull sides examined, 9% had large trigeminal protuberances. Conclusions Based on this study, the posterior petroclinoid dural fold may completely ossify in adults that may lead to narrowing of the porus trigeminus and potential compression of the trigeminal nerve at the entrance to Meckel cave.
authors.affiliation: Department of Anatomical Sciences, St. George's University School of Medicine, Grenada, West Indies.
authors.forename: David
authors.initials: D
authors.lastname: Kimball
authors.affiliation: Department of Anatomical Sciences, St. George's University School of Medicine, Grenada, West Indies.
authors.forename: Heather
authors.initials: H
authors.lastname: Kimball
authors.affiliation: Department of Anatomy, Victor Babes University, Timisoara, Romania.
authors.forename: Petru
authors.initials: P
authors.lastname: Matusz
authors.affiliation: Department of Anatomical Sciences, St. George's University School of Medicine, Grenada, West Indies ; Department of Pediatric Neurosurgery, Children's Hospital, Birmingham, Alabama, United States ; Department of Anatomy and Human Identification, Dundee University, United Kingdom.
authors.forename: R Shane
authors.initials: RS
authors.lastname: Tubbs
authors.affiliation: Department of Anatomical Sciences, St. George's University School of Medicine, Grenada, West Indies ; Department of Anatomy, Medical School Varmia and Mazuria, Olsztyn, Poland.
authors.forename: Marios
authors.initials: M
authors.lastname: Loukas
authors.affiliation: Department of Neurological Surgery, Goodman Campbell Brain and Spine, Indiana University.
authors.forename: A Aaron
authors.initials: AA
authors.lastname: Cohen-Gadol
keywords: cadaver dissection; microanatomy; neurosurgery; petroclinoid dural fold