Eyelashes that grow inwards rather than outwards can indeed irritate the eye by rubbing it whenever the eyelid blinks or the eye moves.
If that is the case, the offending eyelash can often be seen if you look closely at the mirror. Of course, that may not be easy if you are presbyopic/have Lao Hua.
The best course of action if you get frequent eye irritation is to see an eye doctor. There may be other causes of it, even if you think there is an ingrown eyelash.
Eyelashes can grow inwards for no known reason. Other times, eyelid inflammation called blepharitis can cause this to happen, or previous eyelid scarring from injury. In some cases, the eyelashes rub the eye because the eyelid margin rolls inwards-this is called entropion. In children, sometimes a fold of skin pushes upwards on the eyelashes in a condition called epiblepharon.
