Abstract
Purpose: :
To determine how self-reported quality of life using the Impact of Vision Impairment questionnaire (IVI) in patients referred for vision rehabilitation relates to patients’measured visual acuity, contrast sensitivity and central scotoma size.
Methods: :
A retrospective review of new referrals to a vision rehabilitation clinic over a 3 month period was conducted, selecting only patients who had both completed IVI questionnaires and scanning laser ophthalmoscope perimetry. The IVI total scores and three subscales, Mobility, Emotional Health and Reading Ability were calculated, with higher scores reflecting more limited function. Best corrected visual acuity in the better seeing eye and contrast sensitivity in the better seeing eye were tabulated. Scotoma size was measured considering only a scotoma that would overlap when viewing binocularly. Spearman correlation coefficients were calculated by comparing the IVI scores and visual functions.
Results: :
Complete data sets were available for fifty five patients: 60 % were female and 56% had the diagnosis of age-related macular degeneration. Mean age was 72.5. Scotoma locations were found to be to the right of fixation in 27.2%, to the left in 5.5%, superior or inferior in 25.5 %, and central in 16.3%. Scotomas in multiple locations and ring scotomas were seen in 7.3% and 5.5% respectively; 12.7% had no scotomas with binocular viewing. Total IVI scores were not significantly correlated with acuity, contrast sensitivity or size of scotoma. IVI subscale analysis for Mobility and Reading showed statistically significant findings with respect to contrast sensitivity, with correlation coefficients of -0.28 (p=0.04) and -0.43 (p=0.001) respectively. The correlation coefficient between the Reading score and visual acuity was found to be 0.34 (p=0.012).
Conclusions: :
Vision impairment impacts quality of life, affecting not only reading ability, but other daily activities. The correlation between reduced contrast sensitivity and higher self-reported handicap may be an important factor to consider in optimizing vision rehabilitation for patients. Further studies with a larger patient population are needed to detect possible relevance of scotoma size and location.
Keywords: contrast sensitivity • perimetry • quality of life