A dose dependent myopic shift in refraction and axial length in a murine model of lens-induced myopia

Abstract

Purpose : The global increase of myopia is becoming a serious health hazard in the world. To investigate the molecular mechanism of the disease pathogenesis, it is desirable to induce axial elongation in mice with an efficient and effective method in terms of genetic manipulation. Here we show a highly reproducible murine lens-induced myopia (LIM) model and investigate the adaptability of mouse eye to different optical power lenses.

Methods : Frames of the eyeglasses for the murine (LIM) were designed according to the shape of the mouse head, and were made of titanium produced by a 3D-printer. Plus 5 diopter (D), negative 10D, 20D, and 30D lenses made of PMMA were fixed to the right eye side of the frame (n=5 each) and plano 0D lenses were fixed to the left eye side as internal controls. 3-week-old wild-type C57BL/6J mice were attached the eyeglasses by mounting the frame on their skull using a self-cure dental adhesive system. An infrared photorefractor (Steinbeis Transfer Center, Germany) was used to measure the refractive state. The axial length of the eye was analyzed by a SD-OCT system (Envisu R4310, Leica, Germany) under general anesthesia by the combination of midazolam, medetomidine and butorphanol tartrate (MMB).

Results : After three weeks of lens wearing, significant lens power dependencies were observed in both refraction changes (D, control eyes vs affected eyes, average ± standard deviation; +5D group: 7.18±7.67 vs 10.64±8.15, p=0.5; -10D group: 6.86±9.76 vs -15.70±2.54, p=0.001; -20D group: 3.15±5.13 vs -22.19±6.12, p=0.0001; -30D group: -1.31±3.84 vs -26.66±10.86, p=0.0001) and axial length changes (mm, control eyes vs affected eyes, average ± standard division; +5D group: 0.25±0.05 vs 0.27±0.05, p=0.72; -10D group: 0.22±0.02 vs 0.25±0.04, p=0.26; -20D group: 0.24±0.02 vs 0.27±0.03, p=0.07; -30D group: 0.19±0.01 vs 0.25±0.02, p=0.01).

Conclusions : The axial length with -30D lenses was changed more significantly than -20D and -10D lenses according to SD-OCT measurements although the mouse eyes were not fully compensable with -30D lenses. Dose dependent myopia due to lens power was confirmed in our murine LIM model.

This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.