Abstract
Introduction:
The transbasal approach has been modified extensively, and numerous terminologies have been applied to these variations. No common terminology exists to facilitate understanding of the basic variations of this approach. We reviewed the world literature on these approaches and developed a new classification that was validated by its retrospective application to the various published modifications.
Methods:
A retrospective MEDLINE search without time restrictions, along with separate searches of pertinent text references, was performed.
Results:
Over 30 different terminologies were recorded for transbasal approaches. Based on anatomic features, these approaches were classified into four variations. The simplest version, the transbasal approach, consists of a coronal incision with an anterior frontal craniotomy without osteotomy of any parts of the orbital bar for extradural exposure. A level I transbasal approach adds osteotomies of the orbital bar without violation of the medial canthal ligaments. In a level II transbasal approach, the medial canthal ligaments are detached. A level III transbasal approach is similar to a level II approach with the addition of a lateral orbital wall osteotomy to facilitate globe retraction. All published approaches were easily categorized using this classification.
Conclusion:
This new classification provides a common terminology to describe all published variations of transbasal approaches. Its application could facilitate interinstitutional communication and resolve potential confusion created by the existing terminology for transbasal approach variations.