Effect of bilberry extract on slow progression in children: 2-year follow-up study

Aim: To evaluate the effect of oral Difrarel on progression of high myopia in children and to study myopia course after its discontinuation. Methods: A total of 64 highly myopic children were enrolled in this study. Patients were divided into two equal groups: group 1 was administered Difrarel for 1 year and stopped its intake for another year, and group 2 (control) did not take Difrarel. Refraction and axial length of the right eye of every subject were measured every 6 months in both groups. Results: Each group had 32 eyes of 32 patients. The mean age was 9.34 +/- 2.27 years in group 1 and 9.33 +/- 2.2 years in group 2. Mean refraction and axial length at the start of the study were -10.78 +/- 2.6 D and 23.7 +/- 1.2 mm, respectively, in group 1, and -10.5 +/- 2.55 D and 23.9 +/- 1.4 mm in group 2. Refraction and axial length measurements every 6 months revealed statistically significant lower numbers in group 1 than group 2 after 1 year. After discontinuation of the drug, the difference between both groups remained significant. Conclusion: Oral Difrarel slowed axial elongation and stopped myopia progression in children with high myopia. The drug effect was consistent after its discontinuation for 1 year.