title: Relationships of the cisternal segment of the trochlear nerve.
abstract: OBJECTIVE
  The cisternal portion of the trochlear nerve (fourth cranial nerve) can easily be injured during intracranial surgical operations. To help minimize the chance of such injury by promoting a thorough understanding of the anatomy of this nerve and its relationships to surrounding structures, the authors present this anatomical study.
  
  
  METHODS
  In this study, in which 12 cadaveric heads (24 sides) were used, the authors describe exact distances between the trochlear nerve and various surrounding structures. Also described are relatively safe areas in which to manipulate or enter the tentorium, and these are referenced to external landmarks.
  
  
  CONCLUSIONS
  This information will prove useful in planning and executing surgical procedures in and around the free edge of the tentorium cerebelli.
authors.affiliation: Department of Cell Biology, University of Alabama at Birmingham, USA.
authors.forename: R S
authors.initials: RS
authors.lastname: Tubbs
authors.forename: W J
authors.initials: WJ
authors.lastname: Oakes
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002102:Cadaver; D004388:Dura Mater / Q000033:anatomy & histology; D006801:Humans; D008875:Middle Aged; D012886:Skull / Q000033:anatomy & histology; D014321:Trochlear Nerve / Q000033:anatomy & histology* / Q000098:blood supply / Q000601:surgery