Abstract
Purpose: :
To assess patient satisfaction and subjective visual function, using a patient questionnaire, one year after corneal collagen crosslinking (CXL) for keratoconus and corneal ectasia.
Methods: :
107 eyes of 76 patients underwent CXL for keratoconus (n=71) or ectasia (n= 36) in a prospective, randomized controlled trial. Patients completed a subjective questionnaire concerning their visual symptoms, administered preoperatively and at 1 year. Patients ranked symptoms on a scale from 1 to 5 (1= none, 2= mild, 3=moderate, 4=marked, 5= severe). Reported symptoms of photophobia, difficulty night driving, difficulty reading, diplopia, fluctuations in vision, glare, halo, starburst, dryness, pain, and foreign body sensation were analyzed using a student’s t-test. Additionally, improvements in maximum keratometry (Kmax) and best corrected visual acuity (BCVA) were correlated with each of the subjective visual symptoms using Pearson’s correlation.
Results: :
Preoperative to 1 year changes in symptoms were: photophobia 2.7±1.3 to 2.5±1.1; night driving 3.2±1.5 to 2.8±1.5; reading 3.1±1.5 to 2.9±1.3; diplopia 2.5±1.3 to 2.1±1.2; fluctuations in vision 2.6±1.2 to 2.4±1.1; glare 3.1±1.4 to 2.7±1.2; halo 2.9±1.4 to 2.5±1.3; starburst 2.6±1.5 to 2.4±1.4; dryness 2.1±1.2 to 2.0±.1.1; pain 1.6±0.9 to 1.6±0.9; and foreign body sensation 1.8±1.1 to 1.6±0.9. The improvements in night driving (p<.01), difficulty reading (p=.01), diplopia (p<.01), glare (P<.01), halo (P<.01), starbursts (p=.02), and foreign body sensation (p=.01) were statistically significant. All other changes, at 1 year failed to reach statistical significance pphotophobia=.2, pfluctuation=.1, pdryness=.4, ppain=.9). There was no significant difference between the keratoconus and ectasia subgroups. There was a weak, but significant, association between the change in Kmax, and the change in night driving (r=.3, p<.01), pain (r=.2, p=.04), and foreign body sensation (r=.3, p<.01) ratings. There was no association between the change in BCVA and the change in any of the questionnaire ratings at 1 year.
Conclusions: :
One year after CXL, patients note subjective improvement in a number of visual symptoms; specifically, night driving, difficulty reading, diplopia, glare, halo, starbursts, and foreign body sensation.
Clinical Trial: :
http://www.clinicaltrials.gov NCT00647699; NCT00674661