Comparative Evaluation of Ocular Wavefront Characteristics in Bilateral Keratoconus Patients with Unilateral Corneal Vogt’s Striae

Document Type : Original Article

Authors

1 Department of optometry, Refractive Errors Research Center, Mashhad University of Medical Sciences, Mashhad, Iran

2 Cornea Research Center, Khatam‐Al‐Anbia Hospital, Mashhad University of Medical Sciences, Mashhad, Iran

3 Department of optometry, School of Paramedical Sciences, Mashhad University of Medical Sciences, Mashhad, Iran

4 Department of Optometry, Refractive Errors Research Center, Mashhad University of Medical Sciences, Mashhad, Iran

5 Department of Optometry, Zahedan University of Medical Sciences, Zahedan, Iran

Abstract

Purpose: 
The aim of this study was to evaluate and compare ocular wavefront characteristics in bilateral keratoconus (KCN) patients with unilateral corneal Vogt`s striae.
Methods:
In this prospective cross-sectional contralateral eye study, fifty patients diagnosed with bilateral KCN with unilateral corneal Vogt`s Striae with age ranged 20-38 years were recruited. All subjects underwent a comprehensive ophthalmic examination, including monocular uncorrected distance visual acuity, monocular corrected distance visual acuity, refraction (converted to Vetcor component), slit lamp biomicroscopy, Scheimpflug-based tomography (Pentacam HR, Oculus, Germany), and placido disc-based topography (TMS-4, Tomey, Erlangen, Germany). Following pupil dilation, ocular wavefront aberrations were measured by means of iTrace (Tracey Technologies, Houston, Tx). All the ocular wavefront aberrations were evaluated and compared between the KCN eyes with and without Vogt`s striae. Wilcoxon signed rank test was used to compare the parameters. P-value Results:
A total of 50 bilateral KCN patients with the mean age of 27.43±5.46 years were enrolled in this study. The results of this study showed that there were significant differences in the sphere, cylinder, spherical equivalent, uncorrected distance visual acuity, corrected distance visual acuity, and J0 (P <0.05), except for J45 (P=0.58) between two groups. Also, there were significant differences between two groups for some parameters measured by iTrace, including root mean square (RMS) total, RMS low-order total, RMS defocus, RMS Astigmatism, RMS High-order total, RMS Coma, RMS Spherical, and RMS Trefoil (P <0.05), but there was no significant difference for RMS Secondary Astigmatism (P=0.054) between the two groups.
Conclusions:
The iTrace measurements for ocular wavefront showedasignificant increase in the majority of ocular HOA and LOA aberrations in the keratoconic eye with corneal Vogt`s striae compared to the eyes without Vogt`s striae. These results should be noticed in clinical evaluations and treatments of KCN patients with Vogt`s striae.

Keywords

Main Subjects

References

  1. Rabinowitz YS. Keratoconus. Surv Ophthalmol 1998; 42(4): 297-319.
  2. Romero-Jiménez M, Santodomingo-Rubido J, Wolffsohn JS. Keratoconus: a review. Cont Lens Anterior Eye 2010; 33(4): 157-66.
  3. Kymes SM, Walline JJ, Zadnik K, Sterling J, et al. Changes in the quality-of-life of people with keratoconus. Am J Ophthalmol 2008; 145(4): 611-617.
  4. Kennedy RH, Bourne WM, Dyer JA. A 48-year clinical and epidemiologic study of keratoconus. Am J Ophthalmol 1986; 101(3): 267-73.
  5. Gokhale NS. Epidemiology of keratoconus. Indian J Ophthalmol 2013; 61(8): 382-3.
  6. Krachmer JH, Feder RS, Belin MW. Keratoconus and related noninflammatory corneal thinning disorders. Surv Ophthalmol 1984; 28(4): 293-322.
  7. Pinero DP, Nieto JC, Lopez-Miguel A. Characterization of corneal structure in keratoconus. J Cataract Refract Surg 2012; 38(12): 2167-83.
  8. Szczotka LB, Barr JT, Zadnik K. A summary of the findings from the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study. CLEK Study Group. Optometry 2001; 72(9): 574-84.
  9. Hollingsworth JG, Efron N. Observations of banding patterns (Vogt striae) in keratoconus: a confocal microscopy study. Cornea 2005; 24(2): 162-6.
  10. Zadnik K, Barr JT, Edrington TB, Everett DF, et al. Baseline findings in the Collaborative Longitudinal Evaluation of Keratoconus (CLEK) Study. Invest Ophthalmol Vis Sci 1998; 39(13): 2537-46.
  11. Chalita MR, Chavala S, Xu M, Krueger RR. Wavefront analysis in post-LASIK eyes and its correlation with visual symptoms, refraction, and topography. Ophthalmology 2004; 111(3): 447-53.
  12. Williams D, Yoon GY, Porter J, Guirao A, et al. Visual benefit of correcting higher order aberrations of the eye. J Refract Surg 2000; 16(5): S554-9.
  13. Thibos LN, Hong X, Bradley A, Cheng X. Statistical variation of aberration structure and image quality in a normal population of healthy eyes. J Opt Soc Am A Opt Image Sci Vis 2002; 19(12): 2329-48.
  14. Maeda N, Fujikado T, Kuroda T, Mihashi T, et al. Wavefront aberrations measured with Hartmann-Shack sensor in patients with keratoconus. Ophthalmology 2002; 109(11): 1996-2003.
  15. Marcos S. Aberrations and visual performance following standard laser vision correction. J Refract Surg 2001; 17(5): S596-601.
  16. Bailey MD, Mitchell GL, Dhaliwal DK, Wachler BS, et al. Patient satisfaction and visual symptoms after laser in situ keratomileusis. Ophthalmology 2003; 110(7): 1371-8.
  17. Bühren J, Martin T, Kühne A, Kohnen T. Correlation of aberrometry, contrast sensitivity, and subjective symptoms with quality of vision after LASIK. J Refract Surg 2009; 25(7): 559-68.
  18. Moreno-Barriuso E, Lloves JM, Marcos S, Navarro R, et al. Ocular aberrations before and after myopic corneal refractive surgery: LASIK-induced changes measured with laser ray tracing. Invest Ophthalmol Vis Sci 2001; 42(6): 1396-403.
  19. Gobbe M, Guillon M. Corneal wavefront aberration measurements to detect keratoconus patients. Cont Lens Anterior Eye 2005; 28(2): 57-66.
  20. Atchison DA, Collins MJ, Wildsoet CF, Christensen J, et al. Measurement of monochromatic ocular aberrations of human eyes as a function of accommodation by the Howland aberroscope technique. Vision Res 1995; 35(3): 313-23.
  21. Oshika T, Klyce SD, Applegate RA, Howland HC, et al. Comparison of corneal wavefront aberrations after photorefractive keratectomy and laser in situ keratomileusis. Am J Ophthalmol 1999; 127(1): 1-7.
  22. Miháltz K, Kránitz K, Kovács I, Takács A, et al. Shifting of the line of sight in keratoconus measured by a hartmann-shack sensor. Ophthalmology 2010; 117(1): 41-8.
  23. Lim L, Wei RH, Chan WK, Tan DT. Evaluation of higher order ocular aberrations in patients with keratoconus. J Refract Surg 2007; 23(8): 825-8.
  24. Charman WN. Wavefront aberration of the eye: a review. Optom Vis Sci 1991; 68(8): 574-83.
  25. Chakraborty R, Read SA, Collins MJ. Diurnal variations in ocular aberrations of human eyes. Curr Eye Res 2014; 39(3): 271-81.
  26. Awwad ST, El-Kateb M, McCulley JP. Comparative higher-order aberration measurement of the LADARWave and Visx WaveScan aberrometers at varying pupil sizes and after pharmacologic dilation and cycloplegia. J Cataract Refract Surg 2006; 32(2): 203-14.
  27. Cade F, Cruzat A, Paschalis EI, Espírito Santo L, et al. Analysis of four aberrometers for evaluating lower and higher order aberrations. PLoS One 2013; 8(1): e54990.
  28. Guilbert E, Saad A, Elluard M, Grise-Dulac A, et al. Repeatability of Keratometry Measurements Obtained With Three Topographers in Keratoconic and Normal Corneas. J Refract Surg 2016; 32(3): 187-92.
  29. Thibos LN, Horner D. Power vector analysis of the optical outcome of refractive surgery. J Cataract Refract Surg 2001; 27(1): 80-5.
  30. Schwiegerling J, Greivenkamp JE, Miller JM. Representation of videokeratoscopic height data with Zernike polynomials. J Opt Soc Am A Opt Image Sci Vis 1995; 12(10): 2105-13.
  31. Schwiegerling J, Greivenkamp JE. Keratoconus detection based on videokeratoscopic height data. Optom Vis Sci 1996; 73(12): 721-8.
  32. Applegate RA, Hilmantel G, Howland HC, Tu EY, et al. Corneal first surface optical aberrations and visual performance. J Refract Surg. 2000; 16(5):507-14.
  33. Shah S, Naroo S, Hosking S, Gherghel D, et al. Nidek OPD-scan analysis of normal, keratoconic, and penetrating keratoplasty eyes. J Refract Surg 2003: S255-9.
  34. Alió JL, Shabayek MH. Corneal higher order aberrations: a method to grade keratoconus. J Refract Surg 2006; 22(6): 539-45.
  35. 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.
  36. Sabesan R, Yoon G. Visual performance after correcting higher order aberrations in keratoconic eyes. J Vis 2009; 9(5): 6.1-10.

Journal of Paramedical Sciences & Rehabilitation
Volume 7, Issue 2
May 2018
Pages 7-17

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