{
  "abstract": "Background/Objectives: Posterior corneal astigmatism (PCA) varies among individuals, potentially limiting the applicability of population-based estimates. This study aimed to characterize PCA and evaluate high-magnitude PCA and horizontal posterior steep-meridian orientation. Methods: Cataract patients undergoing preoperative biometry with the IOLMaster 700 were assessed for PCA magnitude and orientation. Factors associated with high-magnitude PCA (≥0.50 D) and horizontal orientation were evaluated. Fellow-eye concordance and vector discrepancies between Abulafia–Koch (AK) estimates and measured corneal astigmatism were analyzed. Results: The study included 28,551 patients (28,551 eyes). PCA magnitude was between 0.10 and <0.40 D in 76.6% of eyes, and 91.7% had a vertical posterior steep meridian. High-magnitude PCA and horizontal orientation occurred in 5.1% and 2.5% of eyes. Across PCA magnitude groups, the largest differences involved anterior corneal astigmatism (ACA) magnitude (ε2 = 0.090), total corneal astigmatism (TCA) magnitude (ε2 = 0.047), and age (ε2 = 0.036). Across orientation groups, ACA and TCA magnitude showed the largest differences (ε2 = 0.044 and 0.049). High-magnitude PCA was independently associated with younger age, the female sex, a larger ACA magnitude, and with-the-rule (WTR) ACA. Horizontal orientation was associated with older age, a larger ACA magnitude, against-the-rule (ATR) or oblique ACA, and smaller white-to-white distance (WTW). Discrepancies between AK estimates and measured PCA and TCA were greater in both subgroups, with TCA discrepancies exceeding 0.50 D in 40.6% of high-magnitude and 40.4% of horizontal-orientation eyes. Conclusions: Most eyes followed the conventional PCA pattern, whereas high-magnitude PCA and horizontal posterior steep-meridian orientation showed distinct profiles and greater discrepancies from AK estimates. Population-based estimates may therefore be less representative in these eyes.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Ophthalmology, Shanghai Eye and ENT Hospital, Fudan University, Shanghai 200031, China",
    "NHC Key Laboratory of Myopia, Fudan University, Shanghai 200031, China",
    "Key Laboratory of Myopia, Chinese Academy of Medical Science, Shanghai 200031, China",
    "Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai 200031, China"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 3,
  "authors": [
    {
      "affs": [
        0,
        1,
        2,
        3
      ],
      "name": "Yushen Xu"
    },
    {
      "affs": [
        0,
        1,
        2,
        3
      ],
      "name": "Wenwen He"
    },
    {
      "affs": [
        0,
        1,
        2,
        3
      ],
      "name": "Xiangjia Zhu"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/3tp0ffsncbjsj.bib",
  "cited_by": 0,
  "doi": "10.3390/jcm15218442",
  "fulltext_url": null,
  "id": "3tp0ffsncbjsj",
  "issns": [
    "2077-0383"
  ],
  "landing_url": "https://www.mdpi.com/2077-0383/15/21/8442",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [],
  "openalex": null,
  "pdf_url": null,
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-29",
  "publisher": "MDPI AG",
  "ris": "https://research.draconitic.com/paper/3tp0ffsncbjsj.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:20:01Z",
      "native_id": "10.3390/jcm15218442",
      "source": "crossref",
      "url": "https://www.mdpi.com/2077-0383/15/21/8442"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "journal-openalex:F27",
      "subfield": "general"
    }
  ],
  "title": "Characteristics of Posterior Corneal Astigmatism in 28,551 Chinese Eyes with Cataracts",
  "title_text": "Characteristics of Posterior Corneal Astigmatism in 28,551 Chinese Eyes with Cataracts",
  "type": "peer-reviewed",
  "updated_at": "2026-10-31T00:21:07Z",
  "url": "https://research.draconitic.com/paper/3tp0ffsncbjsj",
  "venue": "Journal of Clinical Medicine",
  "versions": []
}