A Contralateral Eye Study Comparing Corneal Biomechanics in Subjects with Bilateral Keratoconus with Unilateral Vogt’s Striae
Medical hypothesis discovery and innovation in ophthalmology,
Vol. 6 No. 2 (2017),
1 June 2017
Abstract
The aim of this study was to analyze and compare corneal biomechanics in patients with bilateral keratoconus (KCN) with unilateral Vogt’s striae. In this prospective contralateral study, visual acuity, refraction, and corneal biomechanical parameters were evaluated in patients with bilateral KCN with unilateral Vogt’s striae using the Ocular Response Analyzer (ORA) (Reichert Inc., Buffalo, NY) and Corvis ST (Oculus Optikgeräte GmbH, Wetzlar, Germany). All patients underwent a comprehensive ophthalmic examination, including uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), refraction (calculated by vectorial analysis), slit-lamp biomicroscopy, and Scheimpflug-based tomography. The patients enrolled in this study had a reliable diagnosis of bilateral clinical KCN with unilateral Vogt’s striae based on slit-lamp signs as well as corneal topographic/tomographic maps.  Fifty patients aged 18 to 40 years were included in this study. There was a significant difference in all clinical (distance visual acuity and refraction) and corneal biomechanical parameters between KCN eyes with and without unilateral Vogt’s striae (all P < 0.05). However, there were no significant differences in peak distance (P = 0.291), corneal compensated intraocular pressure (IOPCC) (P = 0.08), and J45 (P = 0.131) between the two groups. Most corneal biomechanical parameters, except for peak distance, IOPCC, and J45, showed a significant difference between KCN eyes with and without unilateral Vogt’s striae. Vogt’s striae may cause corneal biomechanical deterioration. This information could be used in clinical practice.ÂReferences
Rabinowitz YS. Keratoconus. Survey Ophthalmol. 1998;42(4):297-319. DOI: 10.1016/s0039-6257(97)00 119-7
Romero-Jimenez M, Santodomingo-Rubido J, Wolffsohn JS. Keratoconus: a review. Cont Lens Anterior Eye. 2010;33(4):157-66; quiz 205. DOI: 10.1016/j.clae.2010.04.006 PMID: 20537579
Kennedy RH, Bourne WM, Dyer JA. A 48-year clinical and epidemiologic study of keratoconus. Am J Ophthalmol. 1986;101(3):267-73. DOI: 10.1016/0002-9394(86)90817-2 PMID: 3513592
Gokhale NS. Epidemiology of keratoconus. Indian J Ophthalmol. 2013;61(8):382-3. DOI: 10.4103/0301-4738.116054 PMID: 23925318
Gomes JA, Tan D, Rapuano CJ, Belin MW, Ambrosio R, Jr., Guell JL, et al. Global consensus on keratoconus and ectatic diseases. Cornea. 2015;34(4):359-69. DOI: 10.1097/ICO.0000000000000408 PMID: 25738235
Kymes SM, Walline JJ, Zadnik K, Gordon MO, Collaborative Longitudinal Evaluation of Keratoconus study g. Quality of life in keratoconus. Am J Ophthalmol. 2004;138(4):527-35. DOI: 10.1016/j.ajo. 2004.04.031 PMID: 15488776
Pinero DP, Nieto JC, Lopez-Miguel A. Characterization of corneal structure in keratoconus. J Cataract Refract Surg. 2012;38(12):2167-83. DOI: 10.1016/j.jcrs.2012. 10.022 PMID: 23195256
McMahon TT, Szczotka-Flynn L, Barr JT, Anderson RJ, Slaughter ME, Lass JH, et al. A new method for grading the severity of keratoconus: the Keratoconus Severity Score (KSS). Cornea. 2006;25(7):794-800. DOI: 10.1097/01.ico.0000226359.26678.d1 PMID: 1706845 6
Hollingsworth JG, Efron N. Observations of banding patterns (Vogt striae) in keratoconus: a confocal microscopy study. Cornea. 2005;24(2):162-6. DOI: 10.1097/01.ico.0000141231.03225.d8 PMID: 1572588 4
Gungor IU, Beden U, Sonmez B. Bilateral horizontal Vogt's striae in keratoconus. Clin Ophthalmol. 2008;2(3):653-5. PMID: 19668769
Somodi S, Hahnel C, Slowik C, Richter A, Weiss DG, Guthoff R. Confocal in vivo microscopy and confocal laser-scanning fluorescence microscopy in keratoconus. Ger J Ophthalmol. 1996;5(6):518-25. PMID: 9479549
Zadnik K, Barr JT, Edrington TB, Everett DF, Jameson M, McMahon TT, et al. Baseline findings in the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study. Invest Ophthalmol Vis Sci. 1998;39(13):2537-46. PMID: 9856763
Mocan MC, Yilmaz PT, Irkec M, Orhan M. The significance of Vogt's striae in keratoconus as evaluated by in vivo confocal microscopy. Clin Exp Ophthalmol. 2008;36(4):329-34. DOI: 10.1111/j.1442-9071.2008.01737.x PMID: 18700919
Roberts CJ. Concepts and misconceptions in corneal biomechanics. J Cataract Refract Surg. 2014;40(6):862-9. DOI: 10.1016/j.jcrs.2014.04.019 PMID: 24857435
Garcia-Porta N, Fernandes P, Queiros A, Salgado-Borges J, Parafita-Mato M, Gonzalez-Meijome JM. Corneal biomechanical properties in different ocular conditions and new measurement techniques. ISRN Ophthalmol. 2014;2014:724546. DOI: 10.1155/2014/7 24546 PMID: 24729900
Meek KM, Tuft SJ, Huang Y, Gill PS, Hayes S, Newton RH, et al. Changes in collagen orientation and distribution in keratoconus corneas. Invest Ophthalmol Vis Sci. 2005;46(6):1948-56. DOI: 10.1167/iovs.04-1253 PMID: 15914608
Pinero DP, Alcon N. In vivo characterization of corneal biomechanics. J Cataract Refract Surg. 2014;40(6):870-87. DOI: 10.1016/j.jcrs.2014.03.021 PMID: 24857436
Kotecha A. What biomechanical properties of the cornea are relevant for the clinician? Surv Ophthalmol. 2007;52 Suppl 2:S109-14. DOI: 10.1016/j.survophthal. 2007.08.004 PMID: 17998034
Touboul D, Roberts C, Kerautret J, Garra C, Maurice-Tison S, Saubusse E, et al. Correlations between corneal hysteresis, intraocular pressure, and corneal central pachymetry. J Cataract Refract Surg. 2008;34(4):616-22. DOI: 10.1016/j.jcrs.2007.11.051 PMID: 18361984
Ruisenor Vazquez PR, Delrivo M, Bonthoux FF, Pfortner T, Galletti JG. Combining ocular response analyzer metrics for corneal biomechanical diagnosis. J Refract Surg. 2013;29(9):596-602. DOI: 10.3928/1081597X-20130710-01 PMID: 23848186
David VP, Stead RE, Vernon SA. Repeatability of ocular response analyzer metrics: a gender-based study. Optom Vis Sci. 2013;90(7):691-9. DOI: 10.1097/ OPX.0b013e318297da45 PMID: 23770655
Kynigopoulos M, Schlote T, Kotecha A, Tzamalis A, Pajic B, Haefliger I. Repeatability of intraocular pressure and corneal biomechanical properties measurements by the ocular response analyser. Klin Monbl Augenheilkd. 2008;225(5):357-60. DOI: 10.1055/s-2008-1027256 PMID: 18454372
Moreno-Montanes J, Maldonado MJ, Garcia N, Mendiluce L, Garcia-Gomez PJ, Segui-Gomez M. Reproducibility and clinical relevance of the ocular response analyzer in nonoperated eyes: corneal biomechanical and tonometric implications. Invest Ophthalmol Vis Sci. 2008;49(3):968-74. DOI: 10.1167/iovs.07-0280 PMID: 18326720
Pinero DP, Alcon N. Corneal biomechanics: a review. Clin Exp Optom. 2015;98(2):107-16. DOI: 10.1111/ cxo.12230 PMID: 25470213
Ali NQ, Patel DV, McGhee CN. Biomechanical responses of healthy and keratoconic corneas measured using a noncontact scheimpflug-based tonometer. Invest Ophthalmol Vis Sci. 2014;55(6):3651-9. DOI: 10.1167/iovs.13-13715 PMID: 24833745
Tian L, Huang YF, Wang LQ, Bai H, Wang Q, Jiang JJ, et al. Corneal biomechanical assessment using corneal visualization scheimpflug technology in keratoconic and normal eyes. J Ophthalmol. 2014;2014:147516. DOI: 10.1155/2014/147516 PMID: 24800059
Nemeth G, Hassan Z, Csutak A, Szalai E, Berta A, Modis L, Jr. Repeatability of ocular biomechanical data measurements with a Scheimpflug-based noncontact device on normal corneas. J Refract Surg. 2013;29(8):558-63. DOI: 10.3928/1081597X-201307 19-06 PMID: 23909783
Vellara HR, Patel DV. Biomechanical properties of the keratoconic cornea: a review. Clin Exp Optom. 2015;98(1):31-8. DOI: 10.1111/cxo.12211 PMID: 25545947
Tian L, Ko MW, Wang LK, Zhang JY, Li TJ, Huang YF, et al. Assessment of ocular biomechanics using dynamic ultra high-speed Scheimpflug imaging in keratoconic and normal eyes. J Refract Surg. 2014;30(11):785-91. DOI: 10.3928/1081597X-20140930-01 PMID: 2529175 7
Thibos LN, Horner D. Power vector analysis of the optical outcome of refractive surgery. J Cataract Refract Surg. 2001;27(1):80-5. DOI: 10.1016/s0886-3350(00)00797-5 PMID: 11165859
Wolffsohn JS, Safeen S, Shah S, Laiquzzaman M. Changes of corneal biomechanics with keratoconus. Cornea. 2012;31(8):849-54. DOI: 10.1097/ICO.0b013e 318243e42d PMID: 22495031
Ambekar R, Toussaint KC, Jr., Wagoner Johnson A. The effect of keratoconus on the structural, mechanical, and optical properties of the cornea. J Mech Behav Biomed Mater. 2011;4(3):223-36. DOI: 10.1016/j.jmb bm.2010.09.014 PMID: 21316609
Lanza M, Iaccarino S, Mele L, Carnevale UA, Irregolare C, Lanza A, et al. Intraocular pressure evaluation in healthy eyes and diseased ones using contact and non contact devices. Cont Lens Anterior Eye. 2016;39(2):154-9. DOI: 10.1016/j.clae.2015.10.001 PMID: 26481062
- Abstract Viewed: 2218 times
- Full Text PDF Downloaded: 1473 times