Abstract
PurposeThis prospective study used anterior segment optical coherence tomography (AS-OCT) to determine how phacoemulsification (phaco) changes iris parameters in eyes with glaucoma or glaucoma suspect status.MethodsUsing Visante AS-OCT (Carl Zeiss Meditec AG), the following pre- and post-phaco parameters were measured: IT750 = iris thickness at 750 μm from the scleral spur; IT2000 = iris thickness 2000 μm from the scleral spur; ITCM = the maximum iris thickness at the middle one third of the iris; ICURV = iris curvature; IAREA = iris area; and pupil size = pupil diameter (mm). Only high-quality images with an identifiable scleral spur were included, and only the nasal quadrant was analyzed. A single glaucoma specialist analyzed the parameters according to the Zhongshan Angle Assessment Program (ZAAP, Guangzhou, China). Multivariate analysis was performed using mixed effects regression correcting for age, gender, and ethnicity.Results89 subjects and 110 eyes were included in this study. The mean age of subjects was 74.83 {+/-} 8.69 years old. Most common diagnoses were POAG and glaucoma suspect (23% and 52%, respectively), and 16% of subjects had an LPI. In multivariate analysis of AS-OCT parameters, decreases in IT750, IT2000, ITCM, ICURV, and pupil size were statistically significant (p<0.05).ConclusionsAfter phacoemulsification, eyes with glaucoma as well as glaucoma suspect eyes have thinner irises and smaller pupils. This may lead to less iris-mediated aqueous outflow obstruction, providing support for early phacoemulsification glaucoma treatment.Translational relevanceOur AS-OCT imaging findings may guide clinical practice as iris parameters become increasingly relevant in preoperative phaco planning.
Highlights
Glaucoma and cataract, two well-known disease entities with an estimated comorbidity of 19.1%, are the leading causes of blindness worldwide [1,2,3]
Our Anterior segment optical coherence tomography (AS-OCT) imaging findings may guide clinical practice as iris parameters become increasingly relevant in preoperative phaco planning
Patients with primary angle closure (PAC) and primary angle closure glaucoma (PACG) derive greater benefit from clear lens extraction compared to laser peripheral iridotomy [23,33,34]
Summary
Two well-known disease entities with an estimated comorbidity of 19.1%, are the leading causes of blindness worldwide [1,2,3]. Existing literature demonstrates that cataract surgery, one of the most commonly performed surgical procedures around the world, tends to lower IOP as well as favorably modify anterior chamber parameters such as lens vault and iris thickness [5,6,7,8,9,10]. The IOP-lowering and anterior chamber-altering effect of phacoemulsification cataract surgery (phaco) has been studied in both nonglaucomatous and glaucomatous eyes [9, 11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31]. In OAG, studies have demonstrated post-operative IOP reduction [12,13,14] and significant post-operative changes in anterior segment parameters such as angle-opening distance (AOD500), supporting the theory that anatomical changes in the anterior segment may be responsible for the IOP-lowering effects of phacoemulsification [7,12]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
