Abstract
Abstract: :
Purpose: To investigate the effect of laser peripheral iridotomy (LPI) on angle depth in patients with anatomically narrow angles, and to describe characteristics associated with successful deepening. Methods: Retrospective chart review. The charts of 795 consecutive patients of one clinician (M.F.) were reviewed. Of these patients, 164 (21%) had anatomically narrow angles less than Shaffer Grade 2. Of these 164 patients, only those who subsequently underwent LPI and were followed for at least one year after presentation and prior to any intraocular surgery were entered into the study. In cases of bilateral treatment, only one eye was randomly selected. Preoperative characteristics, including age, sex, refraction, visual acuity, intraocular pressure, angle depth, anterior chamber depth, lens status, pupil size, iris color, and use of pressure-reducing medications, were analyzed to determine their relationship to the degree of angle deepening following LPI. Results: Forty-one eyes of 41 patients were included in the study. There were 10 males and 31 females. Mean age was 64 years. At presentation, mean values were the following: refraction +1.50 D, IOP 18.5mmHg, anterior chamber depth 2.1 mm, angle depth 0.72, pupil size 2.25 mm. Twenty eyes had brown irides, 10 eyes had blue irides, and 6 eyes had hazel irides. Mean follow-up was 88 months. Two groups were identified on the basis of the degree of angle deepening after LPI: minimal (less than 1.5 grade deepening) and extensive (1.5 grade or greater deepening). Twenty eyes (49%) had minimal deepening, and 21 eyes (51%) had extensive deepening. Age, sex, medications, visual acuity, anterior chamber depth, IOP, lens status, and pupil size at presentation were not associated with degree of angle deepening. An initial angle less than Grade 1 and blue iris color were significantly associated with extensive deepening of the angle following LPI (P=0.046 and P=0.007, respectively). Conclusions: In this study, approximately one-half of the patients who underwent LPI for narrow angles had extensive deepening of the angle. Angle depth and iris color are predictors of the degree of angle deepening following LPI.
Keywords: laser • iris • intraocular pressure