Anterior Chamber Depth, Iridocorneal Angle Width, and Intraocular Pressure Changes After Phacoemulsification: Narrow vs Open Iridocorneal Angles Huang G, Gonzalez E, Peng PH, et al. Anterior chamber depth, iridocorneal angle width, and intraocular pressure changes after phacoemulsification: narrow vs open iridocorneal angles. Arch Ophthalmol. 2011;129(10): Copyright restrictions may apply

Introduction Lens extraction for angle closure and associated glaucoma has been gaining popularity as a plausible alternative. The correlation between iridocorneal angle widening and intraocular pressure (IOP) reduction after cataract surgery has not been thoroughly investigated. Anterior segment optical coherence tomography has been shown to be effective in assessing anterior chamber angle structures. Copyright restrictions may apply

Methods Study Design: Prospective study. Sample/Participants: 26 eyes with narrow angle from 18 patients vs 37 eyes with open angle from 31 patients. Data Analysis: Longitudinal changes in anterior chamber depth, angle opening distance at 500 μm anterior to the scleral spur (AOD500), IOP, and other continuous variables in narrow-angle and open-angle groups were compared statistically using linear mixed models. Limitations: Our cohorts were relatively small, with only 26 eyes that met our criteria for the narrow-angle group and 37 eyes in the control group. Copyright restrictions may apply

Results IOP and Decrease From Preoperative Values Copyright restrictions may apply

Results AOD500 and Change in Width Induced by Cataract Surgery Copyright restrictions may apply

Results Anterior Chamber Depth and Changes in Depth Induced by Cataract Surgery Copyright restrictions may apply

Results Copyright restrictions may apply Anterior segment optical coherence tomography images show a narrow angle before surgery (A), angle widening after phacoemulsification and intraocular lens implantation in the narrow-angle eye (B), an open angle before surgery (C), and angle widening after phacoemulsification and intraocular lens implantation in the open-angle eye (D).

Changes in anterior chamber depth and angle opening distance were significantly related to their respective preoperative parameters in both groups. Each 0.1 mm of increase in AOD500 resulted in a mean (SD) decrease of 0.42 (0.18) mm Hg in IOP (P <.001) in the narrow-angle group. In the open-angle group, each 0.1 mm increase in angle opening distance corresponded to a mean (SD) decrease of 0.32 (0.16) mm Hg (P =.046). Results Copyright restrictions may apply

There is potential clinical relevance of these findings to the treatment of patients with glaucoma. Patients with glaucoma who have more narrow angles prior to phacoemulsification may have greater IOP lowering afterward and a greater possibility of discontinuing 1 or more medications postoperatively. Future studies will further help to elucidate the long-term relationship of the anterior chamber configuration and IOP after phacoemulsification with foldable IOL implantation. Preoperative angle assessment is helpful in predicting the IOP benefit of cataract extraction. Copyright restrictions may apply Comment

If you have questions, please contact the corresponding author: –Shan C. Lin, MD, Department of Ophthalmology, San Francisco School of Medicine, University of California, San Francisco, 10 Koret St, PO Box 0730, San Francisco, CA Funding/Support This study was supported by core grant EY from the National Eye Institute, That Man May See Inc, and Research to Prevent Blindness. Copyright restrictions may apply Contact Information