Monocular and Binocular Visual Function Assessments and Activities of Daily Living Performance in Age-Related Macular Degeneration.

Purpose

To evaluate the relationship between specific monocular and binocular visual function (VF) assessments with binocularly performed activities of daily living task tests (ADLTTs) in patients with age-related macular degeneration (AMD) and healthy controls.

Design

Prospective case-control cohort study.

Subjects

Thirty-six AMD patients and 36 controls.

Method

Visual field assessments included monocular and binocular best-corrected visual acuity (BCVA), contrast sensitivity (CS), and monocular microperimetry testing for mean macula sensitivity, mean retina sensitivity (MRS), fixation area, and fixation distance from fovea (FDF). Age-related macular degeneration lesion area and sensitivity were measured on OCT and microperimetry, respectively. Participants performed 4 validated ADLTTs with binocular BCVA: (1) reading; (2) item-search; (3) money-counting; and (4) multi-step drink-making tasks.

Main outcome measures

Spearman correlations and multivariate regression analysis, adjusted for age, sex, and potential correlation between the 2 eyes, were used to assess the relationship between monocular and binocular VF assessments, and ADLTT performance in both groups.

Results

Age-related macular degeneration patients had poorer VF (BCVA, CS, mean macula sensitivity, and MRS) compared with healthy controls. Monocular BCVA in both better- and worse-vision eyes was moderately correlated with the binocular reading speed and money-counting tasks in participants with AMD. In AMD, monocular worse eye CS, MRS, AMD lesion area on OCT, and lesion sensitivity on microperimetry showed moderate correlations to various ADLTTs, such as reading, money-counting, and drink-making. Similar findings were found in our AMD cohort on multivariate regression analysis. Fewer significant correlations were observed for the better-vision eye, whereas no correlations were observed for healthy controls between VF parameters and ADLTTs. In contrast, significant associations were observed between binocular BCVA and CS with binocular ADLTTs (reading and item-search tasks) but not in AMD patients.

Conclusion

Although monocular BCVA remains the most common measure of VF, CS and microperimetry testing also show significant correlations with ADLTTs performance in AMD patients, and should be considered as complimentary VF-outcome measures in both clinical and research settings. Unlike healthy subjects, AMD patients do not rely on binocular VF for ADLTT function, with the worse-vision eye impacting binocular ADLTT function more than the better-vision eye. Therefore, the worse-vision eye should not be neglected during the management of AMD.

Financial disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.