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Purpose: Considering that a certain proportion of high myopes have reduced visual acuity even after full optical correction, this study aimed to investigate the association between various refractive error components (sphere, cylinder and axis orientation) and reduced visual acuity in individuals with low to high myopia with and without pathologic myopia lesions. Methods:We analysed data from randomly selected eyes of 11,258 individuals with myopia (mean ± SD spherical equivalent (SE) −3.2 ± 2.9D; range: −0.5D to −21.5D). In total, 10,528 individuals had no pathologic myopia lesions. Sphere, cylinder and SE refraction were classified into mild, moderate and high categories.Astigmatism was defined as with-the-rule, against-the-rule or oblique based on the axis orientation. Reduced best-corrected visual acuity was defined as ≥0.18 logMAR. Logistic regression was performed to test factors associated with reduced visual acuity with and without pathologic myopia lesions.Result: Overall, 6.4% (N = 720/11,258) of myopes had reduced best-corrected visual acuity. High sphere (≤−6.0D; Odd ratios [OR]: 16.1; 95% CI: 2.1-126.5), high cylinder (<−2.0 DC; OR: 2.5; 95% CI: 1.8-3.4), against-the-rule (OR: 1.5; 95% CI: 1.1-2.0) and oblique astigmatism (OR: 1.6; 95% CI: 1.2-2.1) were significantly (p ≤ 0.008) associated with reduced visual acuity in the absence of pathologic myopia lesions. Both moderate SE and high myopic SE were also associated with reduced visual acuity.In the presence of pathologic myopia lesions, tessellated fundus (OR: 6.9; 95% CI: 3.5-14.1), chorioretinal atrophy (OR: 7.7; 95% CI: 2.6-19.9) and choroidal neovascularisation (OR: 37.4; 95% CI: 3.3-419.3) were significantly (p ≤ 0.003) associated with reduced visual acuity. Conclusion:Even after full optical correction, both refractive components and pathologic myopia lesions can independently cause reduced visual acuity, regardless of the degree of myopia. K E Y W O R D S myopic lesions, ocular pathologies, reduced vision, risk factors, visual acuityHow to cite this article: Manoharan MK, Thakur S, Dellhi S, Verkicharla PK. Factors associated with reduced visual acuity in myopes with and without ocular pathologies after optical correction.

SIGNIFICANCEOur findings suggest that retinal shapes of the eyes of anisometropes are not different from that of the eyes of isometropes with the same refractions.PURPOSEWe investigated (a) intereye differences in relative peripheral eye lengths between isometropes and anisometropes and (b) if the retinal shape is different between isometropic and anisometropic eyes with the same central refraction.METHODSCentral and peripheral eye lengths were determined along the horizontal meridian in 10° intervals out to ±30° using a noncontact biometer in 28 isometropes and 16 anisometropes. Retinal coordinates were estimated using these eye lengths and ray tracing. Retinal shape was determined in terms of vertex radius of curvature (Rv), asphericity (Q), and equivalent radius of curvature (REq). Linear regression was determined for the REq as functions of central refraction in a subset of isometropic and anisometropic eyes having the same refraction.RESULTSThe differences in relative peripheral eye lengths between the two eyes of anisometropes were significantly greater than for isometropes at ±30° eccentricities. Higher myopic eyes of anisometropes had smaller Rv, more negative Q, and smaller REq than the lower myopic eyes for both isometropes and anisometropes (mean ± standard error of the mean: Rv, 9.8 ± 0.5 vs. 11.7 ± 0.4 mm [P = .002]; Q, −1.1 ± 0.2 vs. −0.5 ± 0.2 [P = .03]; REq, 11.5 ± 0.3 vs. 12.4 ± 0.2 mm [P = .01]). Intercepts and slopes of the linear regressions of REq in anisometropes and their isometropic counterparts with the same refraction were not significantly different from each other (P > .05).CONCLUSIONSHigher myopic eyes of anisometropes had similar retina shapes along the horizontal meridian to those of isometropic eyes with the same refraction.