Author contributions
HTT, VKT, LHL, TVT conceived and designed the study and analysis. TSN, HQN, TTV contributed to data collection and carry out the experiments. LHL, THB, TVT, TDT, TMAD performed analysis and finalizing the results. HTT, THT, VKT, THB, TVT contributed to the drafting of the manuscript. All authors have read and approved the final version for publication.
Acknowledgments
We sincerely thank the patients and their parents for their participation and consents. We thank our colleagues at the Vietnam National Institute of Ophthalmology for helping us with patient recruitment and clinical data collection. This work was supported by funding from the Department of Science and Technology of Hanoi, Vietnam [No grant ID].
Declaration of interest
The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.
Supplementary material
Supplemental data for this article can be accessed at https://doi.org/10.1080/13816810.2019.1616304.