Abstract
Intraocular pressure is affected by corneal thickness and biomechanics. Following ablative corneal refractive surgery, corneal structural changes occur. The purpose of the study is to determine the relationship between the mean central corneal thickness (CCT) and the change in intraocular pressure measurements following various corneal ablation techniques, using different measurement methods. Two hundred myopic eyes undergoing laser in situ keratomileusis (LASIK) or photorefractive keratectomy (PRK) were enrolled into a prospective, non-randomized study. Corneal parameters examined included full ocular examination, measurement of CCT, corneal topography, corneal curvature and ocular refractivity. Intraocular pressure measurements were obtained using three different instruments—non-contact tonometer, Goldmann applanation tonometer and TonoPen XL (TonoPen-Central and TonoPen-Peripheral). All measurements were performed pre-operatively and 4 months post-operatively. Post-operative intraocular pressure was significantly lower than pre-operative values, with all instruments (p value < 0.001, Student's t-test). The post-operative intraocular pressure decrease was smallest using the Tonopen-XL compared to the Goldmann applanation tonometer and non-contact tonometer (p value < 0.001, ANOVA). Intraocular pressure readings are significantly reduced following corneal ablation surgery. We determined in our myopic patient cohort that the TonoPen XL intraocular pressure measurement method is the least affected following PRK and LASIK as compared to other techniques.
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References
Perkins ES, Phelps CD (1982) Open angle glaucoma, ocular hypertension, low tension glaucoma and refraction. Arch Ophthalmol 100:1464–1467
Liu J, Roberts C (2005) Influence of corneal biomechanical properties on intraocular pressure measurement. J Cataract Refract Surg 31:146–155
Schipper I, Senn P, Thomann U, Suppiger M (1995) Intraocular pressure after excimer laser photorefractive keratectomy for myopia. J Refract Surg 11:366–370
Kf Damji, Munger R (2000) Influence of central corneal thickness on applanation intraocular pressure. J Glaucoma 9:205–207
Cheng AC, Fan D, Tang E, Lam DS (2006) Effect of corneal curvature and corneal thickness on the assessment of intraocular pressure using noncontact tonometry in patients after myopic LASIK surgery. Cornea 25:26–28
Garzozi HJ, Chung HS, Lang Y, Kagemann L, Harris A (2001) Intraocular pressure and photorefractive keratectomy: a comparison of three different tonometers. Cornea 20:33–36
Hansen FK, Ehlers N (1971) Elevated tonometer readings caused by a thick cornea. Acta Ophthalmol 49:775–778
Ehlers N, Hansen FK (1974) Central corneal thickness in low-tension glaucoma. Acta Ophthalmol 52:740–746
Argus WA (1995) Ocular hypertension and central corneal thickness. Ophthalmology 102:1810–1812
Boothe WA, Lee DA, Panek WC, Pettit TH (1988) The Tono-Pen: a manometric and clinical study. Arch Ophthalmol 106:1214–1217
Duch S, Serra A, Gastanera J, Abos R, Quintana M (2001) Tonometry after laser in situ keratomileusis treatment. J Glaucoma 10:261–265
Shemesh G, Man O, Michaeli A, Varssano D, Lazar M (2007) Pressure phosphene tonometry versus goldmann applanation tonometry for measuring intraocular pressure before and after LASIK. J Refract Surg 23:405–409
El Danasoury MA, El Maghraby A, Coorpender SJ (2001) Change in intraocular pressure in myopic eyes measured with contact and non-contact tonometers after LASIK. J Refract Surg 17:97–104
Chang DH, Stulting RD (2005) Change in intraocular pressure measurements after LASIK: the effect of the refractive correction and the lamellar flap. Ophthalmology 112:1009–1016
Levy Y, Zadok D, Glovinsky Y, Krakowski D, Nemet P (1999) TonoPen versus Goldmann tonometer after excimer laser photorefractive keratectomy. J Cataract Refract Surg 25:486–491
Minckler DS, Baerveldt G, Heuer DK, Quillen-Thomas B, Walonker AF, Weiner J (1987) Clinical evaluation of the oculab Tono-Pen. Am J Ophthalmol 104:168–173
Moses RA, Marg E, Oechsli R (1962) Evaluation of the basic validity and clinical usefulness of the Mackay-Marg tonometer. Invest Ophthalmol 1:78–85
Kirwan C, O’keefe M (2008) Measurement of intraocular pressure in LASIK and LASEK patients using the reichert ocular response analyzer and goldmann applanation tonometry. J Refract Surg 24:366–370
Dought MJ, Zaman ML (2000) Human corneal thickness and its impact on intraocular pressure measures: a review and meta-analysis approach. Surv Ophthalmol 44:367–408
Kohlhaas M, Spoerl E, Boehm AG, Pollack K (2006) A correction formula for the real intraocular pressure after LASIK for the correction of myopic astigmatism. J Refract Surg 22:263–267
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Hamed-Azzam, S., Briscoe, D., Tomkins, O. et al. Evaluation of intraocular pressure according to corneal thickness before and after excimer laser corneal ablation for myopia. Int Ophthalmol 33, 349–354 (2013). https://doi.org/10.1007/s10792-012-9701-7
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DOI: https://doi.org/10.1007/s10792-012-9701-7