Search Results

You are looking at 1 - 3 of 3 items for

  • Author or Editor: Bernard R. Blais x
  • Refine by Access: All content x
Clear All Modify Search
Bernard R. Blais
in AMA Guides® Newsletter
Bernard R. Blais

Abstract

Use of The Visual System section of the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Sixth Edition, requires knowledge and skills in ophthalmology and assessing impairment. Visual acuity usually is measured using symbols (letters, numbers, pictures, or other symbols) presented in a letter chart format. The Visual Acuity Scale (VAS) is a linear scale with fixed increments and provides a reasonable estimate of acuity-related visual abilities; the associated impairment rating is a reasonable estimate of acuity-related performance loss. This article shows how to perform visual acuity calculations and how to assess impairment of visual fields, including visual field test procedures and calculations. Additional factors can lead to a loss of functional vision and can limit the individual's ability to perform activities of daily living and include contrast sensitivity, glare sensitivity, color vision defects, and binocularity, stereopsis, suppression, and diplopia. If functional vision is affected and is not accounted for by visual acuity or visual field loss, the impairment rating of the visual system can be adjusted but should be limited to an increase of the impairment rating of the visual system by, at most, 15 points (ie, less severe than the total loss of one eye). The ability to rate visual impairment requires significant knowledge and education, and therefore a physician trained in ophthalmology should perform the visual examination and visual system impairment rating.

in AMA Guides® Newsletter
Bernard R. Blais

Abstract

The assessment of visual impairment has been significantly revised from the AMA Guides to the Evaluation of Permanent Impairment (AMA Guides), Fourth Edition. The Fifth Edition, Chapter 12, The Visual System, bases ratings on an estimate of the severity of the effects of certain types of visual loss on the ability to perform activities of daily living (ADLs). Permanent visual impairment is defined as a permanent loss of vision that remains after a patient reaches maximal medical improvement in the underlying medical condition. To assess vision loss, physicians must conduct a visual assessment, including the cause, severity, and prognosis of the underlying disorder and the expected or documented effects of the vision loss on the patient's ability to perform ADLs. Tables in Chapter 12 guide the assessment of visual impairment and consider the results of visual acuity testing, acuity-related impairment rating, and associated classifications. Table 12-10, Classification of Impairment of the Visual System and of the Whole Person, uses clinical data to classify the individual in one of six classes associated with a range of whole person impairment. According to the Fifth Edition of the AMA Guides, examining ophthalmologists or optometrists are required to have new visual acuity charts, appropriate visual field testing equipment, and other equipment for testing contrast sensitivity and glare tests as needed.

in AMA Guides® Newsletter