Evidence map›Paper›PMID 42766274›Full record

ArticleOphthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians (Optometrists)2026

Astigmatism Types Effects on Internal Astigmatism and Compensation in Children: Hong Kong Children Eye Study.

Ka Wai Kam, Arnold S H Chee, Yuzhou Zhang, Erica Shing, Alvin L Young, Clement C Tham, Chi Pui Pang, Li Jia Chen, Jason C S Yam

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Article in Ophthalmic & physiological optics : the journal of the British College of Ophthalmic Opticians (Optometrists), 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

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5 · Who and what money

Authors and funding

9 authors.

Ka Wai KamDepartment of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Shatin, China.
Arnold S H CheeDepartment of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Shatin, China.
Yuzhou ZhangDepartment of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Shatin, China.
Erica ShingDepartment of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Shatin, China.
Alvin L YoungDepartment of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Shatin, China.
Clement C ThamDepartment of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Shatin, China.
Chi Pui PangDepartment of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Shatin, China.
Li Jia ChenDepartment of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Shatin, China.
Jason C S YamDepartment of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Shatin, China. yamcheuksing@cuhk.edu.hk.

Funding

Chinese University of Hong Kong Strategic Impact Enhancement FundHealth and Medical Research Fund 09202466Health and Medical Research Fund 10210246Health and Medical Research Fund 11220206Hong Kong Jockey Club The CUHK Jockey Club Children's Eye Care ProgrammeNational Natural Science Foundation of China 82425017Research Grants Council, University Grants Committee 14102422
6 · The paper itself

Abstract

introductionAstigmatism is highly prevalent among schoolchildren in Hong Kong. Children demonstrate distinct patterns of internal astigmatism (IA) to compensate for corneal astigmatism (CA). This study aims to investigate the associations among astigmatism subtypes, IA and compensation factors (CF) in schoolchildren with a minimum of 0.5 dioptre(D) of refractive astigmatism (RA).

methodsRA was assessed following cycloplegia and classified into simple myopic (SMA), compound myopic (CMA), mixed (MA), simple hyperopic (SHA) and compound hyperopic astigmatism (CHA) based on the location of the focal planes. IA was calculated through vector components. CF were determined by dividing IA by CA in respective vectors.

resultsA total of 4027 children, mean age 7.6 ± 1.0 years, were analysed. CMA (n = 633) was associated with male sex (p = 0.02), older age (β = -0.143, 95% Confidence Interval (CI) -0.201 to -0.085, p < 0.001), longer axial length (β = -0.143, 95% CI -0.158 to -0.129, p < 0.001) and deeper anterior chamber (β = -0.019, 95% CI -0.022 to -0.015, p < 0.001). CHA (n = 1207) showed the greatest mean IA value whereas CMA and SMA (n = 104) had the smallest value. Some 56.1% of those with CHA displayed over-compensation as opposed to 7.9% and 7.6% in CMA and SMA, respectively. To the contrary, 55.6% and 52.9% of CMA and SMA had under-compensation of their astigmatism, compared with 8.2% in CHA.

conclusionChildren with hyperopic astigmatism over-compensate for their CA, whereas children with myopia are more likely to exhibit a greater amount of RA because of lower IA and under-compensation. The differential compensation between hyperopic and myopic children may play a determining role in the development of myopia in school children.

Indexed as

AstigmatismChildrenEpidemiologyMyopiaRefractive errors

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.