AIM: To investigate the temperary changes in the refraction, axial length, and choroidal thickness after a Chinese herb(Zhujing formula)feeding or injection of ranibizumab in a guinea pig myopia model.

METHODS: A Guinea pigs model of form-deprived(FD)myopia were randomly divided into 3 groups: Zhujing formula group, ranibizumab group and saline group(n=20 for each group). Zhujing formula group were fed daily with Zhujing formula solution 3.285g/(kg·d)(1.5mL/d)for 1wk. Ranibizumab group were treated with(intravitreal injections of 0.02mg)ranibizumab at the first day. Saline group were fed with 1.5mL 0.9% saline at the first day. The refraction(Diopter), axial length and choroidal thickness were measured before and at day 1, 3 and 7d postoperative.

RESULTS: The spherical equivalent(SE), axial length and choroidal thickness in ranibizumab group showed no significant trend after intravitreal injection(P>0.05). However, SE and axial length showed trendency to greater myopic shift in the Zhujing formula group and the saline group(P<0.05). The effect began to appear on the first day after administration, achieved the maximum effect after 3d, and faded completely until 7d. On the first day after administration, the diopter and the axial length in ranibizumab group showed the lowest among three groups(P<0.05), and choroid thickness showed the thickest among three groups(P<0.05). At 3d after administration, the diopter and the axial length in the saline group showed the lowest among three groups, and choroid thickness showed the thickest among three groups(P<0.05). There was no significant difference in the parameters among the three groups at 1wk after administration(P>0.05).

CONCLUSION: There is a temperary choroidal thickening of the form deprivation myopia recovery period. The ranibizumab inhibited the thickening of the choroid in the whole recovery period of form deprivation myopia, Zhujing formula slight inhibited the thickening at 3d, and the all change persisted only for 1wk.