Years ago my vision suddenly dropped from 20/50 to 20/200. My Ophthalmologist at the time said "some people just become very nearsighted." I have since read that nearsightedness is caused by the eyeball becoming oval. Is there a measurement that can objectively (as in not assessed by the patient, but seen by the doctor) show this? If so, what is it? Also, could it be possible to become very nearsighted (or more nearsighted) for no disceranable reason? THanks.

get a cycoplegic refraction to rule out pseudomyopia. Have you been doing lots of close work with glasses on when they are NOT needed? What was your 20/50 pescription and whats it now?