Diagnostic value of short-wavelength automated perimetry

Short-wavelength automated perimetry (SWAP) uses a bright yellow background and a large blue stimulus to isolate and measure the sensitivity of short-wavelength-sensitive mechanisms throughout the central 30 degrees visual field. After more than 8 years of cross-sectional and longitudinal studies of patients with early glaucoma, ocular hypertensive patients, and age-matched control subjects, SWAP has been shown to be a sensitive indicator of early damage and progression of loss in glaucoma. It is now available as an optional visual test procedure for routine clinical use on the most widely distributed automated perimeter. Recent investigations have been directed toward refinement and standardization of the technique, as well as toward the influence of other clinical factors (ocular media opacities, macular pigment, statistical interpretation, and related issues) on SWAP. This paper provides a brief overview of current research on SWAP as a clinical diagnostic test procedure.