Visual Acuity Assessment in Persons with Dementia

Abstract

Dementia is the most common cause of disability among the elderly. Each year about 1% of those aged 65 and older-more than 250,000 Americans--develop dementia. Incidence rates for Alzheimer's disease increase from 2.8 per 1,000 person-years for those age 65-69 to 56.1 per 1,000person-years for those over age 90 (Kukull, Higdon, Bowen, Me-Cormick, Teri, Schellenberg, van Belle, Jolley, & Larson, 2002). Alzheimer's disease, by far the most prevalent type of dementia, is characterized by a general decline in intellectual functioning, a progressive declinein memory, impairment in judgment and abstract thinking, and a change in personality (McKann et aI., 1984). The prevalence of dementia increases markedly with age. Dementia is estimated to affect 10% of all those aged 65 and more than 50% of those aged 85 and older, including residents of long-term-care facilities. More than 4 million people in the United States are estimated to have dementia (Cross & Gurland, 1986).Alzheimer's disease is characterized by mild objective memory deficit in the early stages and progresses to more advanced memory loss, a change in personality, severe limitation in communication, and, ultimately, to complete unawareness of the environment in the later stages (Seltzer, Larkin, & Fabiszewski, 1998). Neuropathological changes in the visual cortex of persons with dementia, resulting in changes in visual function, have been documented (Bassi,

The measurement of visual acuity in children: an evidence‐based update

“…For example, success rates with both TAC and Cardiff acuity cards are very high with many studies reporting co-operation for over 90 per cent of patients. 85,87 Grating acuity measures can also be valuable in older patients with cognitive dysfunction; [88][89][90] however, this is not always the case. Chriqui and colleagues 91 recently reported results from three different groups of older participants: a group of young adults (mean age 25 years), a group of older adults without neurological disease (mean age 70 years) and a group of older adults with cognitive impairment.…”

Eye care services for older institutionalised individuals affected by cognitive and visual deficits: a systematic review

“…The search identified 14 studies, mainly from the USA ( n = 9), presenting prevalence data of VI in older residents with dementia and living in LTCF/NH. Due to the design and objectives of the various studies, with one exception, it was not possible to extract accurate data on the prevalence of VI specifically addressing residents ≥65 years and having dementia. The prevalence data in the studies were rather presented for all LTCF/NH residents agreeing to participate or for residents whose clinical charts were available within a given period of time, and not segregated by being 65 years old or by having or not having dementia.…”

“…These studies involved one to 30 LTCF/NH and 100–1591 participants 40–108 years (mean: 72.7–86 years). Various study designs/evaluations were used, such as chart review plus additional testing, retrospective chart review with or without additional testing, population‐based surveys, screening, eye exam by an ophthalmologist/optometrist, or visual acuity testing …”

Three persons with multiple disabilities accessing environmental stimuli and asking for social contact through microswitch and VOCA technology

“…They had congenital encephalopathy with spastic tetraparesis and lack of speech, and sat in wheelchairs. Joe and Albert also presented with total blindness, while Jessie apparently had perception of large objects within her proximity (Geruschat 1992; Morse et al. 2004).…”