Applanation intraocular pressure (IOP) decreases only slightly after a reduction in central corneal thickness (CCT) with myopic photorefrac tive keratektom (PRK)

Purpose. Increase in IOP has heen positivd; correlated with increasing CCT in normal eyes Eyes undergoing f'Rk offer a unique nppi riumi to study the effecl of decreasing CCT on IOP. Methods. A desiripme sludv ofpaiiaiHs undergoing elcimer laser mopic PRK was performed. Eles were excluded fiom PF K if lhe> had glaucoma, corneal, or intraocular pathology IOP u a; measured In GoHmann applanation, and CCT by an ultrasonic pachymeter centered on the pupil We elan ined correlalion between IOP and CCT pre and postop as well as indidu;il poslop changes n IOP vs changes in CCT Results. Results are staled as mean ± SU Pieup liiere u ere 4 eles. 50 7% female and 49 3% male, mean age 38 4 ± 104 Diopters The mean preop IOP was 14 43 ± 2.99 mm l Ig and CCT 544 ± d (m A significant correlation between IOP and CCT was seen both preop (0 41 ~ u 1 7 n,in Hg drop m IOP per 50m decrease in CCT, p=0.015) and at 6 months postop (0 :S2o + o 1'J mm Hg per 50m, p=0 007). There was a significant correbtion beiueen drop in IOP and change in CCT at both 6 (N=220) and 12 (N=167) months (p=u 015, n uii9) '1 he mum change in IOP was -1 04 ± 3 50 at 6 months, and -I 31 ± 3 8d mm Hg at 12 moiilhs CCT changes were -60 7 ± 39 7/m and -56.2 ± 39 Om. respeclixeK No signilicant correl mon was noted between CCT and age, or preop refracthe error Coiiflusioii. Paiienls u idergomg myopic PRK at our institution have a significant decrease in IOP and CCT pos op However. the magnitude of this IOP drop appears small enough .Hal clinical correcii in does not seem warranted in most cases.