Variant myopia – a new presentation?

Purpose: Variant myopia (VM) presents as a discrepancy of > 1 dioptre (D) between subjective and objective refraction, without the presence of any accommodation dysfunction. The purpose of this study is to create a clinical profile of VM. Methods: Fourteen eyes of 12 VM subjects who had a discrepancy of >1D between retinoscopy and subjective acceptance under both cycloplegic and non cycloplegic conditions were included in the study. Fourteen eyes of 14 age and refractive error matched subjects served as controls. Potential participants underwent a comprehensive orthoptic examination followed by retinoscopy (Ret), closed-field autorefractor (CA), subjective acceptance (SA), choroidal and retinal thickness, ocular biometry and higher order spherical aberrations measurements. Results: In the VM eyes, a statistically and clinically significant difference was noted between the Ret and CA and, Ret and SA under both cycloplegic and non-cycloplegic conditions (Multivariate RM ANOVA, p < 0.0001). A statistically significant difference was observed for between the VM eyes, Non-VM eyes and controls for choroidal thickness in all the quadrants (Univariate ANOVA p< 0.05). The VM eyes had thinner choroids (197.21 ± 13.04 microns) compared to the Non-VM eyes (249.25 ± 53.70 microns) and refractive error matched controls (264.62 ± 12.53 microns). No statistically significant differences between groups in RMS of total HOA and spherical aberration were observed. Conclusion: Accommodative etiology does not play a role in the refractive discrepancy seen in individuals with the variant myopic presentation. These individuals have thinner choroids in the eye with variant myopic presentation compared to the fellow eyes and controls. Hypotheses and clinical implications of variant myopia are discussed.