One who is deprived of his eyesight and remains patient, Allah's reward for him will be Paradise
47) Narrated Anas bin Malik : I heard the Prophet saying: Allah said: If I deprive My slave of his two beloved things (i.e. his eyes) and he remains patient, I will let him enter Paradise in compensation for them.
(This Hadith is sound and reported by Bukhari).
The Mercy of Allah is unlimited. Loss of sight in this world is reckoned and the compensation in the Hereafter is Paradise.