Effects of scleral buckling of refraction and ocular growth in young rabbits.

BACKGROUND: There have been a series of reports indicating that scleral buckling (SB) surgery may induce high myopia in advanced retinopathy of prematurity. The mechanism of SB on refractive change in children, however, is not clearly known. We designed this study to investigate the effects of SB on refractive error and ocular growth in young rabbits and demonstrate their mechanisms.

METHODS: For the study, SB surgery was performed on the right eyes of nine 5-week-old rabbits and 11 8-week old rabbits, with encircling buckle. The left eyes were monitored for control. Spherical equivalent, corneal power, and axial length were measured before SB and postoperatively at 2, 4, and 8 weeks. We compared the experimental group with the control group and analyzed the influence of age at the time of operation.

RESULTS: In the control group of eyes, corneal power decreased, axial length increased, and spherical equivalent developed emmetropization with aging. In all eyes that underwent SB surgery, high myopia developed, with the increase in axial length as a major factor in inducing myopia. These changes were greater in the 5-week-old group than in the 8-week-old group. In the eyes that underwent SB surgery, axial length increased more than the eyes in the control group up to 2 weeks after surgery, but ocular growth was arrested after that time.

CONCLUSIONS: SB in young rabbits effects ocular growth and results in high myopia, and an increase of axial length plays a major role in this mechanism. Also, the difference in the effects of SB according to age at the time of surgery may suggest that SB in premature infants could induce a significant axial myopia and secondary amblyopia.