title: [Screening method for angle closure and angle closure glaucoma using scanning laser polarimeter GDxVCC and photodynamic gonioscopy in a darkened room. One-year outcomes of systematic peripheral iridotomy].
abstract: BACKGROUND
  Angle closure glaucoma, a recognized major world health issue disproportionately affecting women and Asians, is not often considered in our European populations, normotensive subjects, myopic patients, or subjects with a deep anterior chamber. Early diagnosis is worthwhile, as laser peripheral iridotomy (LPI) is an effective one-step treatment of the causal mechanism.
  
  
  METHODS
  We have performed a retrospective study of patients who underwent an LPI, the indication for which was based on "photodynamic" gonioscopy in a darkened room showing iridotrabecular contact in darkness. Such photodynamic gonioscopy was motivated by the presence of even minute defects in the nerve fiber layer as seen on the GDxVCC or the presence of a Van Herick sign (narrow limbal anterior chamber depth).
  
  
  RESULTS
  One hundred and three eyes of 103 patients underwent LPI and a minimum 1-year follow-up (mean follow-up almost 2 years). Mean age was 63.7±11.8 years, and women accounted for 63.1% of cases. The vast majority (78.6%) of patients had neither glaucoma nor ocular hypertension. There were 60.1% hyperopes and 39.9% myopes. Over half (57%) had a deep or a very deep anterior chamber. After LPI, there was immediate deepening of the limbal depth of the anterior chamber in 100% of cases. The aqueous humor that flowed forward was almost always viscous-looking. After 1 year, the IOP was 1.3mm Hg±2.4 lower (P<.001) (t test). All patients who had experienced morning headaches (44% of patients) were relieved of this symptom. GDxVCC after 1 year was clearly improved in 18% of cases, slightly improved in 20%, stable in 50%, slightly worse in 11% of cases, and clearly worse in 1%. Cases treated at an earlier stage had a better improvement in GDxVCC.
  
  
  CONCLUSIONS
  Our study shows frequent chronic angle closure in our European population even with deep anterior chambers. Absence of a Van Herick sign does not rule out angle closure at night. A photodynamic gonioscopy with the Goldmann three-lens mirror (to avoid unintentional indentation with the small diameter lenses in these normotensive eyes) should be performed in a darkened room. LPI is an effective one-step treatment of the underlying cause, that is particularly beneficial if performed early.
authors.affiliation: Service d'ophtalmologie, hôpital Foch, 40, rue Worth, BP 36, 92150 Suresnes, France. Electronic address: nmalek@dartybox.com.
authors.forename: N
authors.initials: N
authors.lastname: Malek-Chehire
authors.forename: G
authors.initials: G
authors.lastname: Renard
authors.forename: J-F
authors.initials: JF
authors.lastname: Dreyfus
authors.forename: D A
authors.initials: DA
authors.lastname: Lebuisson
authors.forename: V
authors.initials: V
authors.lastname: Pierre-Kahn
mesh_terms: D000368:Aged; D003624:Darkness; D005260:Female; D005500:Follow-Up Studies; D015812:Glaucoma, Angle-Closure / Q000175:diagnosis* / Q000628:therapy*; D006068:Gonioscopy / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D007498:Iris / Q000601:surgery*; D053685:Laser Therapy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D057109:Scanning Laser Polarimetry / Q000295:instrumentation / Q000379:methods*; D016896:Treatment Outcome
keywords: Angle closure; Angle closure glaucoma; Angle fermé; Contacts irido-trabéculaires; Dépistage; Fermeture nocturne de l’angle; Fibres nerveuses rétiniennes; GDxVCC; Glaucoma screening; Glaucome chronique par fermeture de l’angle; Gonioscopie photodynamique; Iridotomie périphérique préventive; Iridotrabecular contact; Nerve fiber layer analysis; Nocturnal angle closure; Occludable angle; Photodynamic gonioscopy; Prophylactic laser peripheral iridotomy