Classifying Types of Visual Loss Linked With Function to Inform Referral to Vision Rehabilitation for Older Adults in Singapore

Abstract

Objective: Visual impairment restricts performance in activities of daily living. The aim of this study was to classify types of visual loss associated with function in older adults based on clinical data and World Health Organization (WHO) acuity and visual field criteria. Methods: Seven hundred retrospective medical records of older adults seen at the outpatient ophthalmology clinics of a Singapore hospital were reviewed. Extracted data was mapped to the WHO low vision criteria. A flow chart was developed to classify the main types of visual loss aligned with function. Results: The flow chart developed describes four major types of visual loss: (1) full visual field with decreased visual acuity, (2) any visual field loss with greater than ten degrees of available field, (3) peripheral field loss with less than 10° of available field, and (4) any visual field loss due to a cortical event. Within each major type, sub-categories were identified reflecting the complexity of the visual impact of the eye conditions. Conclusion: The flow chart can be applied to outpatient records to identify older adults with different types of visual loss to inform targeted rehabilitation linked with function.

Assessing Older Adults’ Functional Visual Performance Using the Performance Quality Rating Scale

“…The activities selected for observed evaluation using the PQRS-OD approach were identified in a scoping review (Boey et al, 2021) designed to identify functional difficulties that are commonly experienced by older adults with different types of visual loss such as loss of center vision, peripheral field loss, and visual field loss from a cortical event (Boey et al, 2022) and deemed suitable to be tested in an outpatient clinic setting. The following activities were selected:…”

“…The occupational therapist conducts the functional visual evaluation to measure the client’s ability to use vision and decide on interventions to improve the ability to engage in valued occupations (Meyers & Wilcox, 2011), informing patients’ function at the activities and participation levels. Patients experience different types of visual impairment, such as center and/or peripheral field loss (Boey et al, 2022), which may impact occupational performance in different ways.…”

“…To date, no standardized observational assessment has been developed to assess difficulties in performance of activities which are likely to elicit differences in functional visual performance impacted by different types of visual loss (Boey et al, 2022). Such activities should be of varying difficulty and sensitive to visual impairment from decreased acuity, visual field, and/or contrast sensitivity (Stelmack et al, 2003).…”