Introduction: A hospital based case control study was
conducted in government hospitals on contact lens patients
diagnosed with microbial keratitis. Methods: The objective of
this study is to determine the visual outcomes of contact lens
related microbial keratitis. The visual outcomes which
comprised of visual acuity, keratometry readings, corneal
topography findings and contrast sensitivity examinations was
determined after three months from the first presentation at the
hospitals. Results: The mean LogMAR visual acuity during
presentation was 0.96 ± 0.73 or a Snellen equivalent 6/60 (n=76)
and mean LogMAR visual acuity after three months was 0.10 ±
0.48 or a Snellen equivalent 6/7.5 (n=76) with a significant
difference (t=11.22, df=78, p=0.001). Best fit curve for the cases
had a regression coefficient, r=0.350 ± 0.063 (95% CI = 0.224,
0.447, df=78, p=0.001. The visual acuity in cases and controls
was 0.10 ± 0.48 and -0.10 ± 0.14 respectively (t= -3.61, df=154
p=0.001) after three months which showed improvement. There
was a reduction in the corneal uniformity index and corneal
asphericity in the cases. The Corneal Uniformity Index (CU
index) in cases was 63.03 ± 26.38 (n=76) and in controls, 80.13
± 11.30 (n=77), (t= -5.22, df=151, p=0.001). There was also a
reduction in the contrast sensitivity function at all spatial
frequencies in the cases which was significantly different.
Conclusion: Microbial keratitis reduced the vision, corneal
uniformity index, asphericity and contrast sensitivity after three
months in eyes of patients diagnosed with the condition.