Purpose: To explore the clinical relationship between age, interocular differences in the corrected distance(CDVA) and near(CNVA) high contrast logMAR acuities, refractive errors, aniseikonia, axial lengths, pupil sizes, and higher order ocular aberrations (HOAs) on clinical measures of stereoacuity in asymptomatic, presbyopic, habitual spectacle wearers. Methods: 91 subjects underwent clinical assessment of i)subjective refractive error, ii)stereoacuity[arcsecs] at 6m&40cm(Randot Stereotests), iii)aniseikonia[%] at 6m (Awaya test,vertical and horizontal meridia) iv)higher order aberrations(Hartman-Shack aberrometer) v)eyeball length and pupil size(IOL master 700). The resultant aniseikonia(AR) was calculated for pairs of aniseikonia values using Pythagorean theorem. Results: Mean(±sd,95%CI) age of the subjects was 56.2years(±8.10,54.6-57.9). Root mean square(RMS) interocular differences(±sd,95%CI) in spherical refractive errors, axial lengths and pupil sizes were 0.66D(±0.93,0.47-0.85), 0.24mm(±0.33,0.17-0.31), 0.15mm(±0.11,0.12-0.17). Median(mode,interquartile range) values for AR were 2.8(1.0,1.3-4.0). Significant correlations(p

Purpose: To derive and provide analytic formulas for accommodative gain of presbyopia eyes. via sclera ablation and/or thermal shrinkage such that lens is reshaped an/or its positon is shifted. New mechanisms are also proposed. Study Design: To increased accommodation of presbyopia. Place and Duration of Study: New Taipei City, Taiwan, between June, 2021 and July, 2021. Methodology: Accommodation gain is calculated by a 4-component theory, in which the rate functions are derived by an effective eye model for the change of anterior curvature of the lens and its anterior shift. The measured data of accommodative response of the lens versus the lens curvature change and anterior shift are analyzed. The measured net change of the posterior vitreal zonules (PVZ) length and the space between the ciliary body and lens (CLS) during the accommodation are also analyzed. Results: The accommodative gain (AG) is mainly due the change of lens anterior curvature and its anterior shift. The AG per diopter change of the reshaped lens is 0.62 to 0.68 by our formulas, comparing to the measured average value M'=0.69. The efficacy of LASA (or AG) is proportional to the amount of scleral tissue removed (or shrinkaged), such that more space is produced for the change of PVZ and CLS from a UCS to AS for accommodation. Conclusion: The AG is proportional to the amount of scleral tissue removed (or shrinkaged), such that more space is produced for the change of PVZ and CLS from a UCS to AS for accommodation.

This study was aimed to assess visual performance and overall satisfaction of extended depth of focus (EDOF) contact lenses (CLs) in a presbyopic population. We prospectively investigated visual acuity at all distances (0.3, 0.4, 0.5, 0.7, 1, and 5 m), higher-order aberrations (HOAs), contrast sensitivity function, and, overall satisfaction score, before and during EDOF CL wear. Binocular visual acuity at 0.3, 0.5, 0.7, 1, 2, 3, and 5 m when wearing EDOF CLs was 0.01 ± 0.14, -0.08 ± 0.02, -0.08 ± 0.02, -0.08 ± 0.00, -0.08 ± 0.00, -0.08 ± 0.02, and -0.07 ± 0.02, respectively. We found a significant improvement at near to intermediate distances (0.3, and 0.5 m), but no significant change at intermediate to far distances (0.7, 1, 2, 3, and 5 m) between before and during CL wear. The area under the log contrast sensitivity function was not significantly changed neither under photopic nor mesopic conditions (p=0.099, and p=0.689). Ocular third-order aberrations, fourth-order aberrations or total HOAs for a 4-mm pupil significantly increased. The overall satisfaction score significantly improved by wearing EDOF CLs. EDOF CLs significantly improved visual acuity at near to intermediate dis-tances, while maintaining far vision, and the effect of contrast sensitivity was minimal, suggesting its viability of presbyopic correction in such candidates.