Eccentric Correction in Central Visual Field Loss

LICENTIATE THESIS, CERTEC,  LTH NUMBER 2:2001

Jörgen Gustafsson


It is not often that one is instantaneously able to apply the results of basic research. This work is an example of such an exception.

A widely held conviction has been that human peripheral vision could not be improved through optical correction. It was assumed that all limitations in eccentric vision were due to the low density of visual receptors outside the retina's macula. Although rough estimates have demonstrated that peripheral images in this area are not the sharpest, it has still been considered meaningless to correct these optical errors.
This research, however, shows that optical corrections can significantly improve visual acuity as well as contrast sensitivity and balance for people with central scotoma and conscious eccentric fixation. The results have been achieved through the development of new methods for measuring eccentric optics as well as eccentric vision.

Measurment of eccentric refraction with the PowerRefraktor.

The results show great individual variation and that standard correction for off-axis aberrations is not a meaningful task. Instead accurate means of measuring eccentric eye optics and vision have to be created, perhaps initially in the area of low vision rehabilitation.

At Certec the development of measurement methods continues. More case studies and more clinical measurements will be carried out. It is hoped that the research will expand to include a more in-depth study of the effects of optical correction on balance. There has, moreover, been a longstanding interest in investigating how eccentric correction affects people in traffic situations.

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