Ian Bailey, OD, MS, FBCO, FAAO
Research Interests
Low vision; Clinical optics; Clinical assessment of visual performance
In my laboratory studies are being conducted to identify relationships between functional visual abilities and clinical measures of visual function. Face recognition and reading are the functional tasks being investigated and the clinical measures of visual functions include letter chart acuity, grating acuity, visual field, and contrast sensitivity. For this work, we are using subjects who have low vision due to macular degeneration or retinitis pigmentosa. Individuals with these disorders tend to be especially sensitive to illumination conditions, and there are strategic advantages in studying how functional abilities and clinical measures of visual functions vary as a function of the illumination level within the individual subjects. Considerable attention is being given to studying how the design and scoring methods of clinical tests affect the measurement results.
Our visual ergonomics research currently covers visual efficiency and visual adaptation associated with viewing of video display terminals (VDT). We are also investigating pupillary responses and electroretinogram (ERG) responses to scarcely detectable flicker experienced under florescent lighting and for VDT viewing. The visual efficiency research involves comparisons of performances at VDT and hard copy displays using both positive and negative modes of contrast while the subject's vision is blurred using astigmatic lenses. Visual adaptation studies include investigation of changes in color vision, temporal contrast sensitivity and spatial contrast sensitivity as a result of viewing video displays.
Selected Publications
Greenhouse DS, Bailey IL, Howarth PA, Berman SM. Spatial adaptation to text on a video display terminal. Ophthalmic and Physiol Optics, 1992; 12: 302-306
Bailey IL. Detecting early visual loss in the elderly. Optom. Vis. Sci. 1993; 69: 299-305.
Chylack LT Jr, Wolfe JK, Singer D, Leske MC, Bullimore MA, Bailey IL, Friend J, McCarthy D, Wu S-Y, and the LSC Study Group. The Lens Opacities Classification System, version III (LOCS III). Arch Ophthalmol. 1993; 111: 831-836.
Greenhouse DS, Bailey IL, Berman SM, Howarth PA, Temporal. Contrast sensitivity changes associated with simultaneous viewing of two flickering sources. Lighting Research and Technology 1994; 25: 161-166.
Howarth PA, Heron G, Greenhouse DS, Bailey IL, Berman SM. Discomfort from glare. The role of pupillary hippus sources. Lighting Research and Technology 1994; 25: 25-30.