Age of Onset and Progress by Ageing in High Myopia

Abstract The amount of refractive errors, visual acuity, fundus findings, age of onset and other relevant data were examined in 614 cases of myopia, at the Department of Ophthalmology in Juntendo University.
Twenty-seven per cent (27/100 cases) among high myopia (-15.0D ± 7.5D) with typical chorio-retinal atrophy and 20% (55/275 cases) of myopia (-12.7D ± 6.4D) without typical myopic atrophy had onset at 4 yrs old or younger. However, there was no case whose age of onset was 4 yrs old or younger among 239 cases of myopia with 5D or weaker. All of them had onset in 7 yrs old or older.
The average corrected visual acuity became worse as the patient became older, especially in 'high myopia with chorio-retinal atrophy, it was (0.4-0.5 already in childhood and about 0.2 in 40 yrs old or older). However, the corrected visual acuity in high myopia without typical myopic atrophy was kept comparatively good (about 0.7 in 40s or younger and 0.4 in 60s or older). Degree of myopia increased significantly by age, but stopped at around the 40s. These facts show that early age of onset of high myopia is very important.