title: A comparison of external and endoscopic endonasal dacryocystorhinostomy for acquired nasolacrimal duct obstruction.
abstract: OBJECTIVE
  To compare success rates of external dacryocystorhinostomy (DCR) and endoscopic endonasal DCR for acquired nasolacrimal duct obstruction (NLDO).
  
  
  METHODS
  Historical cohort study.
  
  
  METHODS
  100 patients who underwent external DCR and 105 patients who underwent endoscopic endonasal DCR.
  
  
  METHODS
  A retrospective review of medical records of patients with acquired NLDO who underwent DCR from 2004-2010 was performed. Data regarding the lacrimal drainage system, eye examination, surgical outcomes, patient symptom control, and postoperative care were analyzed.
  
  
  METHODS
  Surgical success was defined by patient's resolution of symptoms with patency on irrigation. Surgical failure was defined as no symptomatic reduction in epiphora and/or an inability to irrigate the lacrimal system postoperatively.
  
  
  RESULTS
  A total of 205 patients underwent surgeries for acquired NLDO. The average age was 69 years, and 62.4% of subjects were female. Pooled results showed that both surgical approaches had similar success rates (endoscopic endonasal DCR 82.4% versus external DCR 81.6%; P = 0.895). Complication rates were low in both types of surgery. This included three patients with postoperative hemorrhage (two who had endonasal DCR surgery and one having external DCR surgery). This resolved with conservative treatment. Postoperative problems with lacrimal patency (including canalicular obstruction) occurred to 6.8% of endoscopic patients and 9% of those with the external DCR surgery. Of the 14 patients who had their silicone tubes fall out before the 2-month assessment, 10 were classified as failures (71%), in contrast to only a failure rate of 13.9% of those whose tubes were present for the recommended time. This difference was statistically significant (P < 0.01).
  
  
  CONCLUSIONS
  The success rate of DCR for acquired NLDO in our group of patients was high overall with a low complication rate between the two types of surgery. There was no statistically significant difference between endoscopic and external DCR. Endoscopic surgery may have a benefit of preserving the lacrimal pump system and leaving no surgical scar. Patient preference and availability of each service should direct management. Hence endoscopic endonasal DCR surgery should be considered for primary treatment of nasolacrimal duct obstruction.
authors.affiliation: School of Public Health, Faculty of Medicine, University of Sydney, Sydney, Australia. rushmiak@gmail.com
authors.forename: R
authors.initials: R
authors.lastname: Karim
authors.forename: R
authors.initials: R
authors.lastname: Ghabrial
authors.forename: Tf
authors.initials: T
authors.lastname: Lynch
authors.forename: B
authors.initials: B
authors.lastname: Tang