Abstract
Purpose:
To compare central, para-, and peri-foveal thickness and associated factors in myopic young adults enrolled in the Correction of Myopia Evaluation Trial (COMET) and matched controls without myopia.
Methods:
Twelve years after enrollment, 377/469 (80%) of COMET participants and 206 age-, gender-, and ethnicity-matched young adults without myopia (spherical equivalent refraction (SER) from -0.25D to +1.75D) had measurements of macular thickness taken with high-resolution Optical Coherence Tomography (RTVue) imaging in addition to protocol-specific measurements of refractive error (Nidek) and axial length (AL) (Sonomed). Full macular thickness values for the central (1 mm), para-foveal (1-3 mm), and peri-foveal (3-5 mm) annular regions were calculated and compared within and between COMET participants and controls using univariate and multivariable linear regression analyses.
Results:
94 % (355/377) of COMET participants and 95% (195/206) of controls had reliable OCT data included in the analyses. COMET participants were on average 21.9 (SD-1.3) years old, ethnically diverse (43% White, 28% African-American (A-A), 15% Hispanic, 8.5% Asian and 5% Mixed) and 55% female; controls were similar. Mean SER(SD) and mean AL were -4.96 (1.84) D and 25.4 (0.9) mm for COMET and +0.61 (0.4) D and 23.4 (0.7) mm for controls. The central fovea was thicker in COMET than controls (adj. diff.=6.6μ; p<0.0001), while the other regions were thinner (adj. diff.=-3.5μ in the parafovea, p=0.002, and -9.2μ in the perifovea, p<0.0001). Stratifying by myopia status, multivariable models showed that females had thinner maculas in both groups in all regions (p<0.0001). Central foveal thickness varied by ethnicity in both groups (p<0.0001), with A-A’s having the thinnest and Whites the thickest foveas. Parafoveal thickness varied by ethnic group for COMET (p=0.05) and controls (p=0.04), but perifoveal thickness did not. Longer eyes were associated with thicker central foveas (p=0.003) in COMET but not controls, with thinner perifoveas in both groups (p <0.001) and with thinner parafoveas (p=0.003) in COMET and a similar non-significant relationship in controls.
Conclusions:
In these young adults, myopes have thicker central and thinner para- and peri- foveas than non-myopes. The associations of thinner central foveas with females and African-Americans seen in COMET myopes are consistent with previously published findings and also seen in the non-myopes.
Keywords: 605 myopia •
550 imaging/image analysis: clinical •
585 macula/fovea