title: Gonioscopy and ultrasound biomicroscopy in the detection of angle closure in patients with shallow anterior chamber.
abstract: OBJECTIVE
  To assess the agreement between gonioscopy and ultrasound biomicroscopy (UBM) in detecting angle closure in Chinese patients with shallow anterior chamber.
  
  
  METHODS
  An observational comparative study of the two different examination methods was conducted. Patients with normal intraocular pressure and temporal peripheral anterior chamber depth less than a quarter of corneal thickness based on slit lamp examination were included in this study from December 2007 to May 2009 in the outpatient clinic of First Hospital of Tsinghua University. Gonioscopy was performed with a Goldman goniolens in dark room first and followed by full beam light and indentation. If the filtering trabecular meshwork was invisible or any peripheral anterior synechia was found, that quadrant of the angle was considered closed. UBM was first undertaken in a darkened room then repeated with normal room lighting. If iridotrabecular apposition was showed, that quadrant of the angle was considered closed. The status of angle closure of each quadrant with different methods was recorded.
  
  
  RESULTS
  85 eyes of 46 patients were included in this study. The agreement between gonioscopy and UBM was poor (Κ<0.4) with Kappa analysis in both dark and light conditions in each quadrant. The accordance of agreement between gonioscopy and UBM was hardly affected by age or sex, while in dark condition, eyes with deeper anterior chamber (P=0.005) or plateau iris configuration tended to produce different results (P=0.075) in the 2 methods.
  
  
  CONCLUSIONS
  Gonioscopy and UBM are both indispensable methods for detecting angle closure, neither can completely replace the other.
authors.affiliation: Department of Ophthalmology, First Hospital of Tsinghua University, Beijing 100016, China.
authors.forename: Shan-shan
authors.initials: SS
authors.lastname: Cui
authors.affiliation: Department of Ophthalmology, First Hospital of Tsinghua University, Beijing 100016, China.
authors.forename: Yan-hong
authors.initials: YH
authors.lastname: Zou
authors.affiliation: Department of Ophthalmology, First Hospital of Tsinghua University, Beijing 100016, China; Medical Center Tsinghua University, Beijing 100084, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Li
authors.affiliation: Department of Ophthalmology, First Hospital of Tsinghua University, Beijing 100016, China.
authors.forename: Li-na
authors.initials: LN
authors.lastname: Li
authors.affiliation: Department of Ophthalmology, First Hospital of Tsinghua University, Beijing 100016, China.
authors.forename: Ning
authors.initials: N
authors.lastname: Zhang
authors.affiliation: Department of Ophthalmology, First Hospital of Tsinghua University, Beijing 100016, China; Department of Ophthalmology, Sekwa Eye Hospital, Beijing 100088, China.
authors.forename: Xi-pu
authors.initials: XP
authors.lastname: Liu
mesh_terms: D015812:Glaucoma, Angle-Closure / Q000175:diagnosis*; D006068:Gonioscopy / Q000379:methods*; D006801:Humans