Spectacles are the most common lens treatment to correct myopia. This arm is set to be as a control group for the other two arms. Myopia patients who enter in this group will wear a normal pair of glasses after the baseline examinations (axial length, refraction...).

Myovision is a kind of specially designed, commercially available spectacle lenses that could control the peripheral refraction of myopia patients. Latest studies have changed the understanding of myopia--correcting both central and peripheral vision during lens treatment is indicating to be an effective way of slowing down eye growth. Patients who entered this group will wear a pair of Myovision after baseline examinations.

Orthokeratology has recently been reported as an effective way to control eye growth for myopia adolescents. Patents who enter this group will wear ortho-K lenses during sleep after baseline examinations.

Normal spectacle lenses were used to correct myopia as the control group.

Ocular axial length (AL), which increases with age, will be measured 3 times by an IOLMaster. The first AL examination was considered as the baseline data, and will be repeated 6 and 12 months later.

Spherical Equivalent Refraction (SER), which usually changes from time to time, will be measured 3 times by an open field auto-refractometer. The first SER examination was considered as the baseline data, and will be repeated 6 and 12 months later.