The enigmatic trigeminal caroticodural fold: an anatomic description and surgical relevance to anterior petrosectomy.
OBJECTIVE
We describe our cadaveric dissections and clinical findings that address anterior and ventral limitations imposed by the trigeminal nerve. Particularly, we identify the trigeminal caroticodural fold, the vestment of dura that traverses the space between the nerve and the internal carotid artery. We address the effect of mobilization of this fold to optimize access in Kawase's space when approaching the clivus and posterior fossa.


METHODS
Histological study and cadaveric dissections were performed to examine this regional anatomy. Our clinical series (2002 to 2007) includes 30 patients who underwent anterior petrosectomy as part of more complex approaches for lesions of the skull base.


RESULTS
Histological and dissection specimens showed a dense fibrous confluence lateral to the trigeminal ganglion and portions of the trigeminal nerve that we called the trigeminal caroticodural fold. This fold was prominent in 18 patients, ill-defined in six, and absent in six patients. Incision of the trigeminal caroticodural fold permitted between 1 mm and 3 mm of additional exposure for drilling in Kawase's space without direct trauma to V(3).


CONCLUSIONS
Our study highlights the existence of a dural tethering of the trigeminal nerve and ganglion relevant to surgical exposure of Kawase's space. The regional dural anatomy that contributes to the trigeminal caroticodural fold is complex with subtle variances. We suggest that identification of this fold and its sharp dissection allows mobilization of the trigeminal ganglion and nerve without violation of V(3), and ultimately can improve the transpetrosal access to the upper clivus and posterior fossa via this corridor. Laryngoscope, 2009.
Departments of Otolaryngology-Head and Neck Surgery, Cincinnati, Ohio, USA. editor@mayfieldclinic.com
Myles L
ML
Pensak
Robert G
RG
Kerr
Randal
R
Leung
Jeffrey T
JT
Keller
D000328:Adult; D000368:Aged; D002343:Carotid Artery, Internal / Q000473:pathology* / Q000601:surgery*; D003388:Cranial Fossa, Posterior / Q000473:pathology / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D042282:Microdissection; D008875:Middle Aged; D010579:Petrous Bone / Q000473:pathology* / Q000601:surgery*; D019292:Skull Base Neoplasms / Q000473:pathology / Q000601:surgery; D012668:Trigeminal Ganglion / Q000473:pathology* / Q000601:surgery*; D014276:Trigeminal Nerve / Q000473:pathology* / Q000601:surgery*; D055815:Young Adult