pachymetry

[LadyPit]

How exactly is the corneal thickness measured? I went to an appointment today and the doctor measured each eye in five different areas. Each measurement was noted and then I was told my final measurement. Are the five measurements added together to find the average? Please advise.

[John C Hagan III, MD, FACS, FAAO]

As I said it varies from instrument to instrument you will need to ask your ophthalmologist.  Those numbers if all for central corneal thickness vary much more than our instruments. where the variablity is rarely more thatn +/- 0.005 micron.

JCH MD

[LadyPit]

Dr

They used a Ultrasonic pachymetry

My left eye measures were 623 564 608 607 621
My right eye measures were 572 625 630 621 631

In the end they told me the measurement for both eyes was 570. Not understanding how that arrived at this number

Please advise if you can. The chart where they entered the measurements had five circles one in the middle , one to the left and right and one at the top and bottom. The middle circles for both eyes had the lower measurement

[John C Hagan III, MD, FACS, FAAO]

It varies depending on the instrument.  

Average corneal thickness about 540-555 micron.  Important for following some types of glaucoma disease (thick good, thin bad) and some types of corneal dystrophies.

JCH MD