title: Demonstration of angle widening using EyeCam after laser peripheral iridotomy in eyes with angle closure.
abstract: OBJECTIVE
  To evaluate EyeCam in detecting changes in angle configuration after laser peripheral iridotomy (LPI) in comparison to gonioscopy, the reference standard.
  
  
  METHODS
  Prospective comparative study.
  
  
  METHODS
  Twenty-four subjects (24 eyes) with primary angle-closure glaucoma (PACG) were recruited. Gonioscopy and EyeCam (Clarity Medical Systems) imaging of all 4 angle quadrants were performed, before and 2 weeks after LPI. Images were graded according to angle structures visible by an observer masked to clinical data or the status of LPI, and were performed in a random order. Angle closure in a quadrant was defined as the inability to visualize the posterior trabecular meshwork. We determined the number of quadrants with closed angles and the mean number of clock hours of angle closure before and after LPI in comparison to gonioscopy.
  
  
  RESULTS
  Using EyeCam, all 24 eyes showed at least 1 quadrant of angle widening after LPI. The mean number of clock hours of angle closure decreased significantly, from 8.15 +/- 3.47 clock hours before LPI to 1.75 +/- 2.27 clock hours after LPI (P < .0001, Wilcoxon signed rank test). Overall, gonioscopy showed 1.0 +/- 1.41 (95% CI, 0.43-1.57) quadrants opening from closed to open after LPI compared to 2.0 +/- 1.28 (95% CI, 1.49-2.51, P = .009) quadrants with EyeCam. Intra-observer reproducibility of grading the extent of angle closure in clock hours in EyeCam images was moderate to good (intraclass correlation coefficient 0.831).
  
  
  CONCLUSIONS
  EyeCam may be used to document changes in angle configuration after LPI in eyes with PACG.
authors.affiliation: Singapore National Eye Centre & Singapore Eye Research Institute, Singapore.
authors.forename: Shamira A
authors.initials: SA
authors.lastname: Perera
authors.forename: Desmond T
authors.initials: DT
authors.lastname: Quek
authors.forename: Mani
authors.initials: M
authors.lastname: Baskaran
authors.forename: Tin A
authors.initials: TA
authors.lastname: Tun
authors.forename: Rajesh S
authors.initials: RS
authors.lastname: Kumar
authors.forename: David S
authors.initials: DS
authors.lastname: Friedman
authors.forename: Tin
authors.initials: T
authors.lastname: Aung
mesh_terms: D000869:Anterior Eye Segment / Q000473:pathology*; D005260:Female; D015812:Glaucoma, Angle-Closure / Q000175:diagnosis / Q000601:surgery*; D006068:Gonioscopy / Q000379:methods*; D006801:Humans; D007429:Intraocular Pressure; D032801:Iridectomy / Q000379:methods*; D007498:Iris / Q000601:surgery*; D053685:Laser Therapy; D008297:Male; D008875:Middle Aged; D010781:Photography / Q000379:methods*; D011446:Prospective Studies; D015203:Reproducibility of Results