Sains Malaysiana 50(10)(2021): 3077-3084

http://doi.org/10.17576/jsm-2021-5010-20

Evaluation of the Relationships between Corneal Parameters, Ocular Biometry, and Myopia Magnitude

(Penilaian Hubungan antara Parameter Kornea, Biometri Okular dan Magnitud Miopia)

MOHD IZZUDDIN HAIROL*, NORLAILI ARIF, PUI THENG YONG, MARIAH ASEM SHEHADEH SALEH ALI, NIK NOR ADLINA NIK IDRIS & LI CHING NG

Centre for Community Health Studies, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur, Federal Territory, Malaysia

Received: 8 December 2019/Accepted: 3 February 2021

ABSTRACT

Axial length of the eye correlates with the magnitude of myopia.  However, there are conflicting reports on the relationship between certain corneal parameters with myopia magnitude. The objective of this study was to compare ocular biometry and corneal parameters between emmetropic and myopic groups. Participants (n=127) were categorized as emmetropia (spherical equivalent, SE, ±0.50D), low myopia (-0.75D≤SE<-6.00D) and high myopia (SE≥-6.00D). The difference in axial length, anterior chamber depth, and vitreous chamber depth between emmetrope, low myope, and high myope were highly significant (one-way ANOVA, all p<0.001) with significant correlations between SE and all these parameters (simple regressions, all p<0.001). However, central corneal thickness, corneal radius of curvature, and corneal asphericity between these groups, and the correlations between the ocular parameters with SE were not significantly different (all p>0.05). Corneal curvature correlated significantly with axial length (p=0.001) but not with myopia magnitude (p=0.91). Rather than myopia magnitude, axial length appears to be more sensitive to detect changes in corneal curvature in myopes. In conclusion, myopic patients’ axial length should be carefully considered for interventions that involve the cornea, such as orthokeratology and refractive surgery. 

Keywords: Axial length; central corneal thickness; corneal parameters; myopia; ocular biometry

ABSTRAK

Panjang paksi mata berkorelasi dengan magnitud rabun. Walau bagaimanapun, terdapat laporan yang bertentangan mengenai hubungan antara parameter kornea tertentu dengan magnitud. Objektif kajian ini adalah untuk membandingkan parameter biometri okular dan kornea antara kumpulan emmetropik dan rabun. Peserta (n = 127) dikategorikan sebagai emmetropia (setara sfera, SE, ± 0.50D), miopia rendah (-0.75D≤SE <-6.00D) dan rabun tinggi (SE≥-6.00D). Perbezaan panjang paksi, kedalaman ruang anterior dan kedalaman ruang vitreous antara emmetrope, miop rendah dan miop tinggi sangat ketara (ANOVA sehala, semua p <0.001) dengan korelasi yang signifikan antara SE dan semua parameter ini (regresi sederhana, semua p <0.001). Walau bagaimanapun, ketebalan kornea pusat, jari-jari kelengkungan kornea dan aspherisitas kornea antara kumpulan ini dan hubungan antara parameter okular dengan SE tidak jauh berbeza (semua p> 0.05). Kelengkungan kornea berkorelasi dengan panjang paksi (p = 0.001) tetapi tidak dengan magnitud (p = 0.91). Daripada magnitud rabun, panjang paksi nampaknya lebih sensitif untuk mengesan perubahan kelengkungan kornea pada rabun. Kesimpulannya, panjang paksi pesakit rabun harus dipertimbangkan dengan teliti untuk campur tangan yang melibatkan kornea, seperti ortokeratologi dan pembedahan bias.

Kata kunci: Biometri okular; ketebalan kornea pusat; miopia; panjang paksi; parameter kornea

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*Corresponding author; email: izzuddin.hairol@ukm.edu.my