title: Applied Endoscopic Anatomical Evaluation of the Lacrimal Sac.
abstract: BACKGROUND
  Dacryocystorhinostomy (DCR), a popular surgical procedure, has been performed using an endoscopic approach over recent years. Excellent anatomical knowledge is required for this endoscopic surgical approach. This study was performed in order to better evaluate the anatomical features of the lacrimal apparatus from cadavers in the Isfahan forensic center as a sample of the Iranian population.
  
  
  METHODS
  DCR was performed using a standard method on 26 cadaver eyes from the forensic center of Isfahan. The lacrimal sac was exposed completely, then the anatomical features of the lacrimal sac and canaliculus were measured using a specified ruler.
  
  
  RESULTS
  A total of 26 male cadaveric eyes were used, of which four (16.7%) were probably non-Caucasian. Two (8%) of the eyes needed septoplasty, one (4%) needed uncinectomy, and none needed turbinoplasty. Four (16%) lacrimal sacs were anterior to axilla, one (4%) was posterior and 20 (80%) were at the level of the axilla of the middle turbinate. The mean difference of distance from the nasal sill to the anterior edge of the lacrimal sac (from its mid-height) was 39.04 (±4.92) mm. The mean difference of distance from the nasal sill to the posterior edge of the lacrimal sac (from its mid-height) was 45.50 (±4.47) mm. The mean of width and length of the lacrimal sac was 7.54 (±1.44) mm and 13.16 (±5.37) mm, respectively. The mean difference of distance from the anterior edge of the lacrimal sac to the posterior edge of the uncinate process was 14.06 (±3.00) mm, while the mean difference of distance from the anterior nasal spine to the anterior edge of the lacrimal sac (from its mid-height) was 37.20 (±5.37) mm.The mean height of the fundus was 3.26 (±1.09) mm. The mean difference of distance from the superior punctum to the fundus was 12.70 (±1.45) mm, and from the inferior punctum to the fundus was 11.10 (±2.02) mm.
  
  
  CONCLUSIONS
  Given the differences between the various studies conducted in order to evaluate the position of the lacrimal sac, studies such as this can help to better identify the position of lacrimal sac during surgery based on ethnic differences. In addition, these studies can help novice surgeons to better navigate in a surgical scenario.
authors.affiliation: Department of Otorhinolaryngology, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Seyyed Mostafa
authors.initials: SM
authors.lastname: Hashemi
authors.affiliation: Department of Otorhinolaryngology, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Nezamoddin
authors.initials: N
authors.lastname: Berjis
authors.affiliation: Department of Otorhinolaryngology, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Afrooz
authors.initials: A
authors.lastname: Eshaghian
authors.affiliation: Forensic Medical Center, Isfahan, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Nejadnic
authors.affiliation: Department of Otorhinolaryngology, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Akram
authors.initials: A
authors.lastname: Fereidani Samani
keywords: Anatomy; Dacryocystorhinostomy; Lacrimal Apparatus Diseases; Paranasal Sinuses; Surgery