Association Between Central Corneal Thickness and Axial Length in Patients with Refractive Anomalies and Emmetropes

ORIGINAL ARTICLE
Mimoza Ismaili

 
International Journal of Biomedicine. 2023;13(3):96-100.
DOI: 10.21103/Article13(3)_OA7
Originally published September 5, 2023

Abstract: 

Background: This study aimed to determine the correlation between central corneal thickness (CCT) and axial length (AL) in patients with refractive anomalies and emmetropes.
Methods and Results: The study included 330 respondents, with a total of 660 eyes, divided into two groups. The test group (TG) included 180 respondents with refractive anomalies (65 respondents with hypertropia, 65 with myopia, and 50 with astigmatism); the control group (CG) included 150 respondents with uncorrected visual acuity – 6/6 in both eyes.
The CCT values were higher in the hypermetropic group compared to the myopic group (561.5±25.3 vs. 517.9±37.3 mm, P<0.001), astigmatism group (561.5±25.3 vs. 528.3±35.3 mm, P<0.001) and the CG (561.5±25.3 vs. 553.3±18.5 mm, P<0.001).
From 360 eyes in the TG with refractive anomalies, the lowest AL values were found in the hypermetropic group (21.7±1.0 mm) compared to the myopic group (P<0.001), the astigmatism group (P<0.001), and the CG (P<0.001). Similar differences were also found for the right eyes (OD): hypermetrops tend to have shorter AL than the astigmatic group (P<0.001), myopic group (P<0.001), and the CG (emmetrope) (P<0.001).
Conclusion: The mean CCT value in the hyperopic group was higher than in the emmetropic group, while the CCT value of the myopic and astigmatic group was lower than that of the emmetropic group. AL values were the lowest in the hypermetropic group than in the myopic, astigmatic, and control groups.

Keywords: 
central corneal thickness • refractive anomaly • axial length
References: 
  1. Ehlers N, Bramsen T, Sperling S. Applanation tonometry and central corneal thickness. Acta Ophthalmol (Copenh). 1975 Mar;53(1):34-43. doi: 10.1111/j.1755-3768.1975.tb01135.x. 
  2. Jobke S, Kasten E, Vorwerk C. The prevalence rates of refractive errors among children, adolescents, and adults in Germany. Clin Ophthalmol. 2008 Sep;2(3):601-7. doi: 10.2147/opth.s2836. 
  3. Opubiri I, Adio A, Megbelayin E. Refractive error pattern of children in South-South Nigeria: A tertiary hospital study. Sky J Med & Med Sci. 2013;1:10-4.
  4. Rai S, Thapa HB, Sharma MK, Dhakhwa K, Karki R. The distribution of refractive errors among children attending Lumbini Eye Institute, Nepal. Nepal J Ophthalmol. 2012 Jan-Jun;4(1):90-5. doi: 10.3126/nepjoph.v4i1.5858. 
  5. Holden BA, Sulaiman S, Knox K. The challenge of providing spectacles in the developing world. Community Eye Health. 2000;13(33):9-10. 
  6. Wojciechowski R. Nature and nurture: the complex genetics of myopia and refractive error. Clin Genet. 2011 Apr;79(4):301-20. doi: 10.1111/j.1399-0004.2010.01592.x. 
  7. Remón L, Monsoriu JA, Furlan WD. Influence of different types of astigmatism on visual acuity. J Optom. 2017 Jul-Sep;10(3):141-148. doi: 10.1016/j.optom.2016.07.003.
  8. Shobita N, Selvam VP, Shah VJ, Radha J ,Vijayraghavan V, et al. Correlation of Central Corneal Thickness with Refractive Errorsand Corneal Curvature in the South Indian Population. Acta Scientific Ophthalmology. 2021;4(4):31-38.
  9. Mutti DO, Hayes JR, Mitchell GL, Jones LA, Moeschberger ML, Cotter SA, Kleinstein RN, Manny RE, Twelker JD, Zadnik K; CLEERE Study Group. Refractive error, axial length, and relative peripheral refractive error before and after the onset of myopia. Invest Ophthalmol Vis Sci. 2007 Jun;48(6):2510-9. doi: 10.1167/iovs.06-0562. 
  10. Hitzenberger CK. Optical measurement of the axial eye length by laser Doppler interferometry. Invest Ophthalmol Vis Sci. 1991 Mar;32(3):616-24.
  11.  Schmid GF, Papastergiou GI, Nickla DL, Riva CE, Lin T, Stone RA, Laties AM. Validation of laser Doppler interferometric measurements in vivo of axial eye length and thickness of fundus layers in chicks. Curr Eye Res. 1996 Jun;15(6):691-6. doi: 10.3109/02713689609008911.
  12. He X, Zou H, Lu L, Zhao R, Zhao H, Li Q, Zhu J. Axial length/corneal radius ratio: association with refractive state and role on myopia detection combined with visual acuity in Chinese schoolchildren. PLoS One. 2015 Feb 18;10(2):e0111766. doi: 10.1371/journal.pone.0111766. 
  13. Young TL, Metlapally R, Shay AE. Complex trait genetics of refractive error. Arch Ophthalmol. 2007 Jan;125(1):38-48. doi: 10.1001/archopht.125.1.38. 
  14. Juwayli RMM, Farag AAR, Shalaby AAEA. Correlation between Refractive Errors and Intraocular Pressure after Adjusting by Central Corneal Thickness. The Egyptian Journal of Hospital Medicine. 2021 January;82(3):581-586.
  15.  Mourad MS, Rayhan RA, Moustafa M, Hassan AA. Correlation between central corneal thickness and axial errors of refraction. J Egypt Ophthalmol Soc. 2019;112:52-60.
  16. Iyamu E, Iyamu JE, Amadasun G. Central corneal thickness and axial length in an adult Nigerian population. Journal of Optometry. 2013;6(3):154–160. 
  17. Shisheng Z,Cuiping L, Jingcai L.Analysis of Factors Correlated with Corneal Shape in Myopia. Chinese Journal of Optometry Ophthalmology and Visual Science. 2002;4:43–45.
  18. Liu Z, Pflugfelder SC. The effects of long-term contact lens wear on corneal thickness, curvature, and surface regularity. Ophthalmology. 2000 Jan;107(1):105-11. doi: 10.1016/s0161-6420(99)00027-5.
  19. Pediatric Eye Disease Investigator Group; Bradfield YS, Melia BM, Repka MX, Kaminski BM, Davitt BV, Johnson DA, Kraker RT, Manny RE, Matta NS, Weise KK, Schloff S. Central corneal thickness in children. Arch Ophthalmol. 2011 Sep;129(9):1132-8. doi: 10.1001/archophthalmol.2011.225.
  20. Kadhim YJ, Farhood QK. Central corneal thickness of Iraqi population in relation to age, gender, refractive errors, and corneal curvature: a hospital-based cross-sectional study. Clin Ophthalmol. 2016 Nov 25;10:2369-2376. doi: 10.2147/OPTH.S116743.
  21. Saxena AK, Bhatnagar A, Thakur S. Central Corneal Thickness. Important Considerate in Ophthalmic Clinic. Austin J Clin Ophthalmol. 2017;4:1076.
  22. Nomura H, Ando F, Niino N, Shimokata H, Miyake Y. The relationship between intraocular pressure and refractive error adjusting for age and central corneal thickness. Ophthalmic Physiol Opt. 2004 Jan;24(1):41-5. doi: 10.1046/j.1475-1313.2003.00158.x. 
  23. Hashmani N, Hashmani S, Hanfi AN, Ayub M, Saad CM, Rajani H, Muhammad MG, Aziz M. Effect of age, sex, and refractive errors on central corneal thickness measured by Oculus Pentacam®. Clin Ophthalmol. 2017 Jun 30;11:1233-1238. doi: 10.2147/OPTH.S141313.
  24. Chang SW, Tsai IL, Hu FR, Lin LL, Shih YF. The cornea in young myopic adults. Br J Ophthalmol. 2001 Aug;85(8):916-20. doi: 10.1136/bjo.85.8.916. 
  25. Bhardwaj V, Rajeshbhai GP. Axial length, anterior chamber depth-a study in different age groups and refractive errors. J Clin Diagn Res. 2013 Oct;7(10):2211-2. doi: 10.7860/JCDR/2013/7015.3473.
  26. Shimmyo M, Orloff PN. Corneal thickness and axial length. Am J Ophthalmol. 2005 Mar;139(3):553-4. doi: 10.1016/j.ajo.2004.08.061. 

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Received May 16, 2023.
Accepted June 10, 2023.
©2023 International Medical Research and Development Corporation.