ArticleClinical optometry2019
Posterior corneal astigmatism: a review article.
Article in Clinical optometry, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 21 papers, 1 of them a synthesis that pooled it.
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The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
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Who cites it
21 citing papers in PubMed, 1 synthesis or guideline pooled it, 37 citations in OpenAlex.
- Upper Eyelid Blepharoplasty: Surgical Techniques and Results-Systematic Review and Meta-analysis.Aesthetic plastic surgery · 2023Pooled it
- Outcomes of One Dioptre Toric IOL Correction in Low Corneal Astigmatism: A Comparison with Non-toric IOLs.Ophthalmology and therapy · 2026Article
- Age-related changes in corneal parameters in the Turkish population: a Pentacam-based study.BMC ophthalmology · 2026Article
- Association between dry eye and myopia in schoolchildren: current evidence and possible mechanisms.Frontiers in medicine · 2026Review
- Impact of Ocular Residual Astigmatism on Visual and Refractive Outcomes Following Photorefractive Keratectomy.Advanced biomedical research · 2026Article
- Experimental investigation of focal position in regular astigmatic eyes with zero spherical equivalent.Scientific reports · 2025Article
- Anterior Segment Swept-Source Optical Coherence Tomography-based Assessment of Corneal Refractive Profiles in Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis Patients: A Controlled Comparative Study.Korean journal of ophthalmology : KJO · 2025Article
- Innovations and Outcomes in Astigmatism Correction During Cataract Surgery: A Comprehensive Review.Cureus · 2024Review
- Quantitative evaluation of corneal irregularity and scarring after infectious keratitis using anterior segment optical coherence tomography.Graefe's archive for clinical and experimental ophthalmology = Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie · 2024Observational
- Normative Topographic Anterior and Posterior Corneal Astigmatism: Axis Distribution and Its Relations with Ocular and Biometric Parameters.Journal of clinical medicine · 2023Article
- Evaluation of Refractive Accuracy of ORA and the Factors Impacting Residual Astigmatism in Patients Implanted with Trifocal IOLs During Cataract Surgery: A Retrospective Observational Study.Clinical ophthalmology (Auckland, N.Z.) · 2022Article
- Observational
- Corneal Structural Changes in Congenital Glaucoma.Eye & contact lens · 2022Article
- On the Relationship between Corneal Biomechanics, Macrostructure, and Optical Properties.Journal of imaging · 2021Article
- Refractive errors and risk factors for myopia in infants aged 1-18 months in Tianjin, China.BMC ophthalmology · 2021Article
- Corneal and lens densitometry in patients with vernal keratoconjunctivitis.International ophthalmology · 2021Article
- Analysis of corneal astigmatism and aberration in chinese congenital cataract and developmental cataract patients before cataract surgery.BMC ophthalmology · 2021Article
- Analysis of Tear Ferning Patterns in Young Female Subjects with Refractive Errors.Journal of ophthalmology · 2021Article
- Posterior Corneal Asphericity Effect on Postoperative Astigmatism after EDOF Intraocular Lens Implantation in Cataract Patients.Journal of ophthalmology · 2021Article
- Prevalence and Age-Related Changes of Corneal Astigmatism in Patients Undergoing Cataract Surgery in Northern China.Journal of ophthalmology · 2020Article
Corrections and comments
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Authors and funding
3 authors at 2 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Most human eyes show at least a small degree of corneal astigmatism and it can arise from both surfaces of the cornea. The shape of the anterior corneal surface provides no definitive basis for knowing the toricity of the posterior surface. In the previous studies, average astigmatism of the posterior corneal surface was -0.26 to -0.78 diopter. The radius of the posterior corneal surface is less than the radius of the anterior corneal surface. Most studies have found a clear correlation between the anterior and posterior corneal asphericities and the asphericity of the posterior surface is independent of the vertex radius of curvature, refractive error and gender. In contrast to the anterior corneal surface, the asphericity of the posterior corneal surface varies significantly between meridians. The anterior and posterior corneal surface would have approximately parallel principal meridians and both of these surfaces are often flatter in the horizontal meridian than the vertical one. This is especially true in the higher degrees of corneal astigmatism, and then about 10% of any anterior corneal astigmatism is neutralized by an astigmatism arising from the posterior corneal surface. Although the second corneal surface only contributes to about 10% of the total refractive power of the eye, a precise knowledge of its morphology is needed for the correct diagnosis and monitoring the corneal diseases or the surgical interventions and in many eyes neglecting the posterior corneal surface measurement may lead to significant deviations from the corneal astigmatism estimation. In this article, we have reviewed the shape and the toricity of the posterior corneal surface and also the effect of age on it. We investigated the contribution of posterior corneal astigmatism to the total corneal astigmatism and evaluated the accuracy of corneal astigmatism estimation by neglecting the posterior corneal surface measurement.
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Registered trials
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.