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Published on: December 1, 2023
Concordancia entre biómetros ópticos basados en OCT de fuente barrida y basados en Scheimpflug en niños miopes
Ying-Yan Qin1, Zhao-Tian Zhang1, Shu-Wen Xing1
1State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangdong Provincial Clinical Research Center for Ocular Diseases, Guangzhou 510060, Guangdong Province, China.
Aim:
To evaluate the agreement of axial length (AL), anterior chamber parameters, and total cornea power obtained by swept-source optical coherence tomography (SS-OCT)-based and Scheimpflug-based optical biometers in myopic children.
Methods:
AL, steep keratometry (K), flat K, posterior corneal keratometry (PK), total keratometry (TK), anterior chamber depth (ACD), horizontal corneal diameter (CD), and central corneal thickness (CCT) were obtained using IOL Master 700 and Pentacam AXL. The agreement between the devices was evaluated using intraclass correlation coefficients (ICC), Bland-Altman plots, and astigmatism vector analysis.
Results:
Totally 175 myopic children (48.5% male) with a mean age of 10.29±2.14y were enrolled. The ICC and Bland-Altman plots indicated a satisfactory agreement for AL, ACD, and CCT. The mean difference in CD of -0.31±0.30 mm was considered clinically significant (>0.2 mm). Additionally, measurements of K and TK obtained from the IOL Master 700 showed good agreement. Nevertheless, there were clinically significant differences observed in PK, simulated keratometry (simK), total cornea power, and astigmatism (at least 10% of the cases with a difference of >10 degrees in meridian) between the two devices.
Conclusion:
The study findings demonstrate a significant difference in K, PK, astigmatism, and CD, indicating that the two optical biometers cannot be considered interchangeable. Therefore, it is recommended to utilize one kind device for follow-up examinations in myopic children.
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