Title: A Study of Corneal Parameters in Myopic Patients
Authors: Malarvizhi C, Chitra Raghavan, Valsa T Stephen
DOI: https://dx.doi.org/10.18535/jmscr/v7i2.95
Abstract
Purpose: To study the central corneal thickness, corneal curvature and axial length in patients with myopia.
Methods: 64 eyes of 32 myopic patients were included in this cross sectional study.Central corneal thickness, axial length and corneal curvature were measured using ultrasonic pachymeter, A SCAN ultrasonic instrument, auto refractometer respectively. Correlation between these three variables was analysed.
Results: The degree of myopia ranges from-0.5 to -16 D (3.5±3.0D). The mean CCT was 540.9±33.36µm. Mean axial length was 24.5±1.4mm. Mean corneal curvature was 44.08±1.35D. CCT showed a statistically significant positive correlation with degree of myopia (r=0.298, p=0.017), and axial length (r=0.276, p=0.027). A statistically significant negative correlation was found between axial length and corneal curvature (r= -0.443, p = <0.001). A statistically significant association was found between axial length and degree of myopia (p =<0.001). In this study, 31.3% were males and 68.7% were females. Mean age was 27.6±3.8 years. Axial length showed a statistically significant association with age and sex. However, CCT didn’t show any association with age and sex.
Conclusion: This study showed a statistically significant positive correlation between CCT, degree of myopia and axial length. CCT didn’t show any correlation with corneal curvature. CCT didn’t show any significant association with age and sex. Axial length showed a highly significant positive correlation with the degree of myopia and a statistically significant negative correlation with corneal curvature. Axial length showed a statistically significant association with age and sex.
Keywords: Central corneal thickness, axial length,corneal curvature, myopia.
References
- Corneal thickness, epithelial thickness and axial length differences in normal and high myopiaXiao gang Wang†, Jing Dong† and Qiang WuBMC Ophthalmology201515:49 https://doi.org/10.1186/s12886-015-0039-6
- Am J Ophthalmol. 1956 Aug;42(2):251-66.Corneal thickness; its measurement and changes VON BAHR G
- Correlations between Magnitude of Refractive Error and Other Optical Components in Korean Mopes Sangkyu Lee, Boyun Kim, Tae-Hoon Oh, Hyun Seung Kim Korean J Ophthalmol 2012;26(5):324-330 pISSN: 1011-8942 eISSN: 2092-9382 http://dx.doi.org/10.3341/kjo.2012.26.5.324
- Oliveira C., Tello C., Liebmann J., Ritch R. Central corneal thickness is not related to anterior scleral or axial length. J Glaucoma. 2006
- Cho P, Lam C. Factors affecting the central corneal thickness of Hong Kong-Chinese. Curr Eye Res. 1999; 18(5):368–374.
- Suzuki S, Suzuki Y, Iwase A, et al. Corneal thickness in an ophthalmologically normal Japanese population. Ophthalmology. 2005; 112(8):1327–1336.
- L. Llorente, S. Barbero, D. Cano, C. Dorronsoro, and S. Marcos, “Myopic versus hyperopic eyes: axial length, corneal shape and optical aberrations,” Journal of Vision, vol. 4, no. 4, pp. 288–298, 2004.
- Hashemi H, Yazdani K, Mehravaran S, Khabaz Khoob M, Mohammad K, Parsafar H, et al. Corneal thickness in a population based, cross sectional study: the Tehran Eye Study. Cornea. 2009; 28:395–340
- Xu L, Zhang H, Wang YX, Jonas JB. Central corneal thickness and glaucoma in adult Chinese: The Beijing Eye Study. J Glaucoma. 2008;17(8):647–653.
- Foster PJ, Baasanhu J, Alsbirk PH, Munkhbayar D, Uranchimeg D, Johnson GJ. Central corneal thickness and intraocular pressure in a Mongolian population Ophthalmology. 1998;105(6):969–973
- Hidasi V., Kolozsvári L. (1997) Age-related changes of axial length and configuration of progressive myopic eyes. In: Cennamo G., Rosa N. (eds) Ultrasonography in Ophthalmology XV. Documenta Ophthalmologica Proceedings Series, vol 61. Springer, Dordrecht
- Šelović, A., Juresa, V., Ivankovic, D., Malcic, D. and Šelović Bobonj, G. (2005), Relationship between axial length of the emmetropic eye and the age, body height, and body weight of schoolchildren. Am. J. Hum. Biol., 17: 173–177. doi:10.1002/ajhb.20107