title: Ostium shrinkage after endoscopic dacryocystorhinostomy.
abstract: OBJECTIVE
  Ostium closure after endoscopic dacryocystorhinostomy (DCR) is the commonest cause for anatomic failure. We aimed to determine the changes in size of the DCR ostium over time and investigate the correlation of ostium size and surgical outcomes.
  
  
  METHODS
  A single surgeon, prospective, nonrandomized, noncomparative, interventional case series.
  
  
  METHODS
  We included a consecutive series of patients who underwent powered endonasal DCR. All patients had radiologically confirmed nasolacrimal duct or canalicular obstruction.
  
  
  METHODS
  Patients were operated on by 1 surgeon (D.S.) and follow-up was at 4 weeks and 12 months. Ostium sizes were measured at the end of surgery and at 4 weeks and 12 months after surgery.
  
  
  METHODS
  Intraoperative and postoperative ostium size, correlation of ostium size, and surgical outcome.
  
  
  RESULTS
  We included 161 patients who fulfilled the inclusion criteria. Three patients were lost to follow-up. The ostium measured 8.6 (95% confidence interval [CI], 5.0-12.2) by 13.4 (95% CI, 10.3-16.5) at the time of surgery and 5.7 (95% CI, 2.3-9.0) by 9.5 (95% CI, 6.0-13.0) at 4 weeks, and 4.8 (95% CI, 1.9-7.7) by 8.2 (95% CI, 4.5-11.9) at 12 months. There was significant ostial shrinkage from surgery to 4 weeks (mean shrinkage of 50%) and from 4 weeks to 12 months (mean shrinkage of a further 15%). The intraoperative ostium size and postoperative size were positively correlated. Ostial size was not predictive of final ostial patency and symptomatic resolution of epiphora.
  
  
  CONCLUSIONS
  After endoscopic DCR, the final ostium size on average is 35% of the original at 12 months postoperatively. The majority of the ostium shrinkage occurs within 4 weeks postoperatively with a lesser degree of shrinkage between 1 and 12 months postoperatively. Ostium size was not predictive of overall surgical outcome.
  
  
  BACKGROUND
  The authors have no proprietary or commercial interest in any of the materials discussed in this article.
authors: South Australian Institute of Ophthalmology, Royal Adelaide Hospital, Adelaide, Australia. onn912@gmail.com
authors: WengOnn
authors: W
authors: Chan
authors: Dinesh
authors: D
authors: Selva
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003608:Dacryocystorhinostomy; D004724:Endoscopy; D005260:Female; D015590:Fluorophotometry; D006801:Humans; D007440:Intubation; D007767:Lacrimal Duct Obstruction / Q000000981:diagnostic imaging; D008297:Male; D008875:Middle Aged; D009301:Nasolacrimal Duct / Q000000981:diagnostic imaging / Q000601:surgery*; D011183:Postoperative Complications; D011446:Prospective Studies; D011859:Radiography; D012008:Recurrence; D055815:Young Adult