title: Pathogenesis of canalicular lacerations.
abstract: OBJECTIVE
  To assess the pathogenesis of canalicular lacerations.
  
  
  METHODS
  This is a retrospective, clinical case series of 236 patients who sustained a canalicular laceration. All patients who presented to the oculoplastic service of 3 individuals (D.R.J., S.M.G., L.A.M.) from May 1, 1998 to September 30, 2007, with a canalicular laceration were included in the study. Case histories were carefully reviewed in an attempt to classify the mechanism of injury as: "direct (penetrating) injury," "indirect (avulsive)," or "diffuse (avulsive)." Associated injuries (floor fractures, soft tissue lacerations, etc.) were also recorded.
  
  
  RESULTS
  Of the 236 patients reviewed, direct canalicular injuries were detected in 128 (54.2%), indirect injuries were detected in 60 (25.4%), and diffuse injuries were detected in 48 (20.3%). Avulsive blunt injuries (due to indirect or diffuse trauma) therefore accounted for 45.7% of the lacerations whereas direct penetrating injuries accounted for 55.2% of the canalicular lacerations. Other injuries associated with the trauma occurred in 152 of the 236 patients (64%). Lacerations involving other portions of the eyelids, periocular area, and face made up the greatest number of associated injuries, and occurred with equal frequency in the direct penetrating group and the indirect/diffuse (avulsive injury) group. Associated injuries more serious in nature including orbital fractures, globe rupture, other body injuries, and head trauma were more commonly seen when diffuse trauma was involved.
  
  
  CONCLUSIONS
  Direct, indirect, or diffuse forces may injure canaliculi but direct penetrating injuries were more common than avulsive injuries. More serious injuries (orbital fractures, globe rupture, other body injuries, and head trauma) were more commonly seen when diffuse trauma was involved.
authors.affiliation: Department of Ophthalmology, University of Ottawa Eye Institute, Ottawa Hospital, Ottawa, Ontario, Canada. jordan1897@rogers.com
authors.forename: David R
authors.initials: DR
authors.lastname: Jordan
authors.forename: Setareh
authors.initials: S
authors.lastname: Ziai
authors.forename: Steven M
authors.initials: SM
authors.lastname: Gilberg
authors.forename: Louise A
authors.initials: LA
authors.lastname: Mawn
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D015807:Eye Injuries, Penetrating / Q000150:complications*; D005260:Female; D006801:Humans; D007223:Infant; D022125:Lacerations / Q000209:etiology*; D007765:Lacrimal Apparatus / Q000293:injuries*; D008297:Male; D008875:Middle Aged; D009917:Orbital Fractures / Q000209:etiology; D012189:Retrospective Studies; D014949:Wounds, Nonpenetrating / Q000150:complications*