Effect of High Myopia on Dynamic Changes of Anterior Angle After Pharmacologic Mydriasis in Cataract Patients: A SS-ASOCT Study

Abstract

Purpose The purpose of this study was to evaluate the effect of high myopia on anterior angle change after pharmacologic mydriasis in patients with cataract using swept-source anterior segment optical coherence tomography (SS-ASOCT). Methods This prospective cross-sectional study continuously recruited patients with cataract aged 40 years and older during the period August 2019 to August 2020. The anterior segment parameters, including central corneal thickness (CCT), anterior chamber depth (ACD), angle opening distance (AOD), angle recess area (ARA), trabecular iris space area (TISA), trabecular-iris angle (TIA), angle to angle width (ATA), and anterior chamber volume (ACV), were obtained using SS-ASOCT at baseline and 30 minutes after mydriasis. Regression analyses were performed to identify the factors related to the relative change of AOD500 (ΔAOD500). Results A total of 938 patients (938 eyes) were included. The AOD500 decreased from 0.46 ± 0.22 mm to 0.40 ± 0.19 mm, with percent ΔAOD500 of −13.59% ± 37.73% ( P = 0.005). The patients with high myopia had a smaller reduction of anterior angle parameters, with a percent ΔAOD500 of −22.74% ± 58.09%% in non-high myopic eyes and −0.84% ± 45.47% in high myopic eyes ( P < 0.001). The stepwise multivariate regression demonstrated that the smaller reduction of AOD500 were independently associated with younger age (coefficient = −2.11, 95% confidence interval [CI] = −2.59 to −1.64, P < 0.001), presence of high myopia (coefficient = 15.35, 95% CI = 3.63 to 27.07, P = 0.010), greater baseline TISA500 (coefficient = 60.78, 95% CI = 8.75 to 112.82, P = 0.022), and ATA (coefficient = 11.21, 95% CI = 4.53 to 17.89, P = 0.001). Conclusions The anterior chamber angle decreased after pharmacologic mydriasis in these patients with cataract. Angle shallowing after pharmacologic mydriasis was significantly less pronounced in high myopic eyes than in non-high myopic eyes. Translational Relevance These findings are informative for the relative less risk of angle-closure glaucoma in highly myopic eyes.

Associations between anterior segment biometry and high axial myopia in 3438 cataractous eyes in the Chinese population

“…However, despite the great significance of anterior segment biometry for refractive cataract surgery, there have been few studies on the relationship between high axial myopia and anterior segment biometric characteristics [ 1 , 11 , 12 ]. Some previous studies on healthy subjects have partially explored the link between myopic refraction and anterior segment biometry [ 13 – 16 ].…”

Changes in Dimensions and Functions of Crystalline Lens in High Myopia Using CASIA2 Optical Coherence Tomography

“…However, lens shape and functions have scarcely been studied in HM population with stabilized refractive status. In addition, dynamic changes of crystalline lens during accommodation depend on the structural changes, and refractive status can be an interference factor for myopia patients in modulating the ocular dynamics [17].…”