Prevalence and Ocular Biometric Characteristics of Myopia in Primary Angle Closure Disease in Rural China: The Handan Eye Study

Abstract

Purpose The purpose of this study was to determine the prevalence of myopia among patients with primary angle closure disease (PACD) in rural China and their ocular biometric characteristics. Methods Study subjects were recruited from the Handan Eye Study. A/B-mode scan (Cine Scan, Quantel Medical, Cedex, France) was used to measure the axial length, anterior chamber depth (ACD), and lens thickness (LT). PACD was defined as the anterior chamber angle being considered closed when 180 degrees or more of the posterior pigmented trabecular meshwork were not visible on the gonioscopy. Myopia was defined as a spherical equivalent (SE) refractive error ≤−0.5 diopter (D). Persons who did not meet PACD definition were classified as the open-angle (OA) group. Results The overall prevalence of myopia in persons with PACD was 13.7% (11.6% in primary angle closure suspect [PACS], 21.6% in primary angle closure [PAC], 62.5% in primary angle closure glaucoma [PACG]). The age-specific prevalence of myopia in PACD eyes was 41.7% at 30 to 39 years old, 12.3% at 40 to 49 years old, 8.7% at 50 to 59 years old, 10.7% at 60 to 69 years old, and 31.7% at age 70 years and over. PACD had shorter AL (22.2 ± 0.8 vs. 22.9 ± 0.9 mm, P < 0.001), shallower ACD (2.3 ± 0.3 vs. 2.8 ± 0.4 mm, P < 0.001), and greater LT (5.0 ± 0.5 vs. 4.7 ± 0.5 mm, P < 0.001). PACD had even thicker lenses and deeper ACD with age than those with OA (all P ≤ 0.025) from 30 years to 70 years of age and over. Conclusions Myopia was common among persons with PACD who were less than 40 years of age in this rural Chinese population, and over half of those with PACG were myopic.

Publication trends of primary angle-closure disease during 1991-2022: a bibliometric analysis

“…However, with respect to the latest focus, the other clusters have attracted more attention. Gonioscopy remains the most important diagnostic method and the gold standard for assessing the presence and degree of angle-closure [7] . However, it is highly subjective and its findings vary with the amount of light and mechanical compression in the eye during examination [35] .…”

“…Other factors associated with narrow ACA found by UBM and AS-OCT include increased iris thickness, greater iris curvature, larger iris area, and iris volume [40][41][42] . Anterior segment dimension parameters such as small anterior chamber depth (ACD), width, area, and volume are also associated with PACG [7,43] . In recent years, the development of OCT technology, especially the application of SS-OCT in anterior segment imaging, has greatly improved image acquisition speed, resolution, and scan depth and width [9] .…”

“…The risk factors associated with PACD include ethnicity, older age, female gender, small cornea, shallow anterior chamber, thick lens, anterior lens position, and short axial length (AL) [6] . To assess the presence of angle closure, gonioscopy is the most important method [7] . However, the findings are subjective and vary with the light and mechanical compression of the eye during examination.…”