Hi,

I had my LASIK preop exam done in late November and then again in early January. The measurements of my corneal thickness differed each time - first time it was around 560, second time around 530 (both eyes about the same). The measurements were done in the same office, though by different people.

Any idea how could this happen? I can't believe the cornea could change so much within 1.5 months.

Can the numbers depend on the person who is measuring it? For example if they just lightly touch the eye with the sensor or if they put more pressure into it? Anybody else experienced such a difference?

In both cases I was not wearing my soft contacts for more than a week before the exam.

How near-sighted are you. In most situations, the difference between these measurements are unimportant. 530 and 560 are not dramatically different, and could be caused by the technician not pointing the probe in the perfect direction. For example - if the probe is tilted - it will read as if the cornea is thicker - because the ultrasound waves will travel farther

I hope this helps

Bill Trattler, MD
Miami, FL