Measuring and Correction Methods of H.-J. Haase Improve Binocular Vision in Patients with Severe Anisometropia

<b>Background/Objectives:</b> To compare binocular vision status after spectacle correction using Measuring and Correction Methods of H.-J. Haase (MCH) and Optometric Extension Program (OEP) methods in patients with severe anisometropia and impaired fusion, including those with a history of monocular cataract surgery. <b>Methods:</b> This retrospective, observational comparative study analyzed the medical records of 34 patients with severe anisometropia (≥3.00 D) who were fitted with spectacles at Yi-Ming Optometry Clinic between January 2019 and May 2023. Patients were aged 32 to 82 years and had no ocular or systemic comorbidities affecting visual function. Binocular vision data previously recorded using the MCH and OEP methods were extracted and analyzed. All data are expressed as mean ± standard error, and <i>p</i>-values ≤ 0.05 were considered statistically significant. <b>Results:</b> The mean anisometropia and heterophoria measurements were 5.51 ± 0.45 and 2.26 ± 0.32 D (∆), respectively. The mean MCH and OEP oculus uterque visual acuity measurements were -0.020 ± 0.010 and 0.040 ± 0.010 log-MAR (<i>p</i> < 0.001), respectively. In the right eye, the horizontal prisms for MCH and OEP were 0.780 ± 0.128 and 0.020 ± 0.020 (∆) (<i>p</i> < 0.001), whereas those of the left eye were 0.790 ± 0.119 and 0.040 ± 0.025 ∆ (<i>p</i> < 0.001), respectively. The mean MCH and OEP stereo vision measurements were 97.560 ± 7.888 and 167.120 ± 17.295 arcsec (<i>p</i> < 0.001), respectively. <b>Conclusions:</b> The findings indicate that MCH prism resulted in superior stereo vision and binocular visual acuity compared to OEP in severe anisometropia patients.