{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,17]],"date-time":"2026-10-17T10:49:05Z","timestamp":1792234145704,"version":"4.4.0"},"reference-count":15,"publisher":"Springer Science and Business Media LLC","issue":"8","license":[{"start":{"date-parts":[[2024,3,8]],"date-time":"2024-03-08T00:00:00Z","timestamp":1709856000000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2024,3,8]],"date-time":"2024-03-08T00:00:00Z","timestamp":1709856000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/100031307","name":"Johannes Kepler University Linz","doi-asserted-by":"crossref","id":[{"id":"10.13039\/100031307","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Graefes Arch Clin Exp Ophthalmol"],"published-print":{"date-parts":[[2024,8]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Purpose<\/jats:title>\n                    <jats:p>This study aimed to estimate the corneal keratometric index in the eyes of cataract surgery patients who received zero-power intraocular lenses (IOLs).<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methodology<\/jats:title>\n                    <jats:p>\n                      This retrospective study analyzed postoperative equivalent spherical refraction and axial length, mean anterior curvature radius and aqueous humor refractive index to calculate the theoretical corneal keratometric index value (\n                      <jats:italic>n<\/jats:italic>\n                      <jats:sub>k<\/jats:sub>\n                      ). Data was collected from 2 centers located in France and Germany.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Thirty-six eyes were analyzed. The results revealed a mean corneal keratometric index of 1.329\u2009\u00b1\u20090.005 for traditional axial length (AL) and 1.331\u2009\u00b1\u20090.005 for Cooke modified axial length (CMAL). Results ranged from minimum values of 1.318\/1.320 to maximum values of 1.340\/1.340.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>The corneal keratometric index is a crucial parameter for ophthalmic procedures and calculations, particularly for IOL power calculation. Notably, the estimated corneal keratometric index value of 1.329\/1.331 in this study is lower than the commonly used 1.3375 index. These findings align with recent research demonstrating that the theoretical corneal keratometric index should be approximately 1.329 using traditional AL and 1.331 using CMAL, based on the ratio between the mean anterior and posterior corneal curvature radii (1.22).<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s00417-024-06435-8","type":"journal-article","created":{"date-parts":[[2024,3,8]],"date-time":"2024-03-08T02:01:27Z","timestamp":1709863287000},"page":"2533-2539","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Leaving trusted paths: Estimating corneal keratometric index in cataract surgery eyes with zero-power implants"],"prefix":"10.1007","volume":"262","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9603-0500","authenticated-orcid":false,"given":"Damien","family":"Gatinel","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Peter C.","family":"Hoffmann","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David L.","family":"Cooke","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexandre","family":"Chingan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guillaume","family":"Debellemani\u00e8re","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9175-6177","authenticated-orcid":false,"given":"Achim","family":"Langenbucher","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4145-2559","authenticated-orcid":false,"given":"Jascha A.","family":"Wendelstein","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2024,3,8]]},"reference":[{"key":"6435_CR1","doi-asserted-by":"publisher","first-page":"351","DOI":"10.1016\/j.jcrs.2018.12.026","volume":"45","author":"DL Cooke","year":"2019","unstructured":"Cooke DL, Cooke TL (2019) Approximating sum-of-segments axial length from a traditional optical low-coherence reflectometry measurement. 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Dr. Gatinel received speaker honoraria from BVI outside the submitted work. Dr. Hoffmann received speaker fees from Hoya and Johnson & Johnson outside the submitted work. Dr. Wendelstein received research grants from Carl Zeiss Meditec AG. He received speaker honoraria from Carl Zeiss Meditec AG, Alcon Surgical, Bauch and Lomb, Rayner Surgical, and Johnson & Johnson Vision outside of the submitted work. He was supported by an \u201cESCRS Peter Barry Fellowship Grant.\u201d Dr. Langenbucher reports speaker honoraria from Hoya Surgical and Johnson & Johnson Vision outside the submitted work. Apart from this, all authors certify that they have no affiliations with or involvement in any organization or entity with any financial interest (such as honoraria, educational grants, participation in speakers\u2019 bureaus, membership, employment, consultancies, stock ownership, or other equity interest, and expert testimony or patent-licensing arrangements), or non-financial interest (such as personal or professional relationships, affiliations, knowledge or beliefs) in the subject matter or materials discussed in this manuscript. This article does not contain any studies with animals performed by any of the authors. This article is a retrospective chart review and does not contain any studies with human participants performed by any of the authors; all data processed in this study were already anonymized at the source before being transferred to us for processing. The local ethics committee has provided a waiver for this study (\u00c4rztekammer des Saarlandes, 157\/21). This precludes any back-tracing of the identity, and therefore informed consent of the patients was not necessary. All procedures performed in this study were in accordance with the ethical standards of the \u00c4rztekammer des Saarlandes and with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards. No funding was received for this research.","order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Declarations"}}]}}