The Influence of Visual Acuity and Contrast Sensitivity on Subjective Evaluation of Visual Function before and after Cataract Surgery

Overview

Purpose:
To assess the influence of visual acuity and contrast sensitivity on subjective evaluation of visual function investigated by means of questionnaires in patients before and after cataract surgery.

Methods:
Visual acuity was tested on Snellen projection optotypes and logMAR optotype chart with Landolt rings, contrast sensitivity was tested on Pelli- Robson chart. The questionnaire included Visual Functioning Index VF-14, Cataract Symptom Score and Global Measures of Vision – self-reported trouble and satisfaction with vision. 37 cataract patients were examined, including completing the questionnaire, 1 day before and 7 weeks after the surgery.

Results:
Most patients (65 %) suffer from moderate troubles with their vision and are moderately dissatisfied (51 %) before cataract surgery. After the surgery, a majority of patients have no troubles (51 %) and are very satisfied (54 %). Visual acuity (VA) correlates only with VF-14, namely only VA of non-operated eye (p < 0.01), binocular VA before (p < 0.001) and after surgery (p < 0.05). Contrast sensitivity (of non-operated eye, operated eye, binocular) correlates with more subjective parameters (VF-14, self-reported trouble and satisfaction with vision), namely both before and after the surgery (p < 0.05, p < 0.01, p < 0.001).

Conclusion:
After cataract surgery, visual acuity, contrast sensitivity and subjective parameters of visual functions significantly improve. Subjective parameters correlate more with contrast sensitivity then with visual acuity. Contrast sensitivity is more related than visual acuity to real world in patients with cataract.

Key words:
visual acuity, contrast sensitivity, subjective evaluation, correlation