title: Follow-up of primary angle closure suspects after laser peripheral iridotomy using ultrasound biomicroscopy and A-scan biometry for a period of 2 years.
abstract: OBJECTIVE
  To determine the morphologic changes in the anterior segment of primary angle closure suspects (PACS) who underwent laser peripheral iridotomy (LPI) for a period of 2 years.
  
  
  METHODS
  PACS (n=82 eyes) of Asian Indian origin who attended the Glaucoma clinic of tertiary eye hospital underwent A-scan biometry and ultrasound biomicroscopy. Anterior chamber depth, anterior chamber angle (ACA), axial length, lens thickness, relative lens position, central corneal thickness, angle opening distance 500, trabecular-ciliary process distance, iris-ciliary process distance, and iris thickness were measured before LPI and after LPI at 1 week, 6 months, 1 year, 1.5 years, and 2 years. Variation in the parameters measured over a period of 2 years was analyzed.
  
  
  RESULTS
  Fifteen eyes out of 52 eyes developed into primary angle closure (PAC) with synechial changes. Univariate analysis for the predictive factors of PAC showed no significant association for age, sex, narrow angle, ultrasound biomicroscopy parameters, and vertical cup-disc ratio. When analyzed as continuous variables, decreasing ACA was significant risk factor (95% confidence interval: 0.703, 0.989, P=0.037). Iris-ciliary process distance, ACA, lens thickness, and angle opening distance 500 were the parameters that varied significantly (P<0.05) between "before LPI group" and "after LPI groups." None of the subjects developed increased intraocular pressure after laser iridotomy.
  
  
  CONCLUSIONS
  In this hospital-based study on the course of PACS subjects after LPI, as many as 28% progressed to PAC. Decreasing ACA was the predictive factor for the progression of PACS to PAC. There was no increase in intraocular pressure, history, or symptoms of acute attack of glaucoma among the study subjects after LPI.
authors.affiliation: Department of Glaucoma, Elite School of Optometry, Medical and Vision Research Foundation, 41 College Road, Chennai, Tamilnadu, India.
authors.forename: Krishna Kumar
authors.initials: KK
authors.lastname: Ramani
authors.forename: Baskaran
authors.initials: B
authors.lastname: Mani
authors.forename: Ronnie J
authors.initials: RJ
authors.lastname: George
authors.forename: Vijaya
authors.initials: V
authors.lastname: Lingam
mesh_terms: D000869:Anterior Eye Segment / Q000473:pathology; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D015812:Glaucoma, Angle-Closure / Q000175:diagnosis / Q000601:surgery*; D006068:Gonioscopy; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D032801:Iridectomy; D007498:Iris / Q000601:surgery*; D053685:Laser Therapy; D053844:Lasers, Solid-State / Q000627:therapeutic use; D008297:Male; D033401:Microscopy, Acoustic; D008875:Middle Aged; D009798:Ocular Hypertension / Q000175:diagnosis / Q000601:surgery*; D012029:Refraction, Ocular / Q000502:physiology; D012307:Risk Factors; D014065:Tonometry, Ocular