have weak eyes.However, even after crossing 25, I was able to restore my vision partly. And my father (doctor himself) and his eye specialist friend were stunned. They could not believe that mere barefoot regular exercise, diet regime, surya vandana could show such results. It took 2 years continuous efforts to achieve this. (It was in year 2006-07)
Basically, I dedicate it to sheer will power and devotional confidence in Surya Namaskar.
In Ayurveda, there are herbs and procedures to improve the vision.
Now modern medicine says that vision can be restored. By similar mechanical methods.
It is possible but it demands regular regime, devotion, faith and will power.