Abstract
Purpose :
The aim of this study was to evaluate the efficacy of a new system of binocular refraction, mainly based on ocular aberrometry, (BROA) and to compare with the traditional subjective refraction (SR) in patients with keratoconus.
Methods :
Prospective, double blind and transversal study was performed. It was recruited 50 keratoconus patients with mean age of 36.10 ± 10.20 years old (age range: 24 to 51 years). SR was performed by two different optometrists and BROA by other optometrist (three times), randomly. Neither patients nor optometrist knew the refraction achieved by the others. For statistical analysis, the refraction was converted to vectorial parameters (M, J0 and J45). Then, best corrected visual acuity (BCVA), subjective vision evaluated with visual analogue scale (VAS), refraction spent time and M, J0 and J45 were analyzed. Student t-test for related samples were used to compare the efficacy between binocular refraction based on aberrometry and subjective refraction. Data are represented as mean ± SD and p value<0.05 were consider statistically significant
Results :
The vectorial parameters of refraction was found very similar between both methods studied, without statistically differences (p>0.05). For M, was found -3.15 ± 4.05 D and -2.98 ± 3.63 D for BROA and SR, respectively. Both refraction methods showed similar BCVA, being 0.09 ± 0.19 LogMAR for binocular refraction based on aberrometry and 0.04±0.17 for SR (p>0.05). The main difference was found in the spent time to perform the refraction. The time spent with BROA was 5.07 ± 1.24 minutes meanwhile it was 7.37 ± 2.31 minutes for SR, being statistically significant (p<0.05). Regarding the VAS, the mean score was 81.12 ± 17.03 and 81.29 ± 18.54 for BROA and SR, respectively, without significant differences (p>0.05).
Conclusions :
The BROA shows an excellent repeatability and a similar behavior than SR, spending less chair time. The BROA seems to be a good tool for refraction for keratoconus patients.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.