title: Agreement between gonioscopy and ultrasound biomicroscopy in detecting iridotrabecular apposition.
abstract: OBJECTIVE
  To assess the agreement between findings obtained at dark-room gonioscopy and ultrasound biomicroscopy (UBM) in the diagnosis of iridotrabecular apposition in light and dark conditions.
  
  
  METHODS
  We enrolled patients with appositional angle closure at dark-room gonioscopy performed using a 1-mm slitlamp beam that did not cross the pupil. Ultrasound biomicroscopic images were acquired in normal room light and subsequently with all room lights off. Images were evaluated for the presence or absence of iris-cornea contact. The angle opening distance at 500 microm was calculated.
  
  
  RESULTS
  Iridotrabecular apposition in at least 1 angle quadrant was demonstrated in all 18 eyes at dark-room gonioscopy, 17 eyes (94%) at dark-room UBM, and only 10 eyes (56%) at UBM in room light. Of 18 superior angles that were appositionally closed at dark-room gonioscopy, apposition was demonstrated on UBM images in 16 (89%) in a dark room but only 6 (33%) in room light. Angle opening distance was less during dark-room gonioscopy in all but the nasal quadrant.
  
  
  CONCLUSIONS
  We found high agreement between gonioscopy and UBM when both are performed in a completely dark room. Our findings support the recommendation that, in routine clinical practice, gonioscopy be performed in a dark room to avoid misdiagnosis of treatable iridotrabecular apposition.
authors.affiliation: Department of Ophtalmology, Assaf Harofeh Medical Center, Zerifin, Israel.
authors.forename: Yaniv
authors.initials: Y
authors.lastname: Barkana
authors.forename: Syril K
authors.initials: SK
authors.lastname: Dorairaj
authors.forename: Yariv
authors.initials: Y
authors.lastname: Gerber
authors.forename: Jeffrey M
authors.initials: JM
authors.lastname: Liebmann
authors.forename: Robert
authors.initials: R
authors.lastname: Ritch
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003624:Darkness; D005260:Female; D015812:Glaucoma, Angle-Closure / Q000175:diagnosis*; D006068:Gonioscopy / Q000379:methods*; D006801:Humans; D007429:Intraocular Pressure; D007498:Iris / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D033401:Microscopy, Acoustic / Q000379:methods*; D008875:Middle Aged; D015203:Reproducibility of Results; D014129:Trabecular Meshwork / Q000000981:diagnostic imaging* / Q000473:pathology