{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,2]],"date-time":"2026-01-02T07:51:56Z","timestamp":1767340316672,"version":"build-2065373602"},"reference-count":45,"publisher":"Georg Thieme Verlag KG","issue":"06","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Klin Monbl Augenheilkd"],"published-print":{"date-parts":[[2023,6]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>Belin\u02bcs ABCD keratoconus classification system allows keratoconus staging based on the criteria of anterior (A) and posterior (B) corneal curvature, thinnest corneal thickness (C), and best spectacle-corrected visual acuity (D). These parameters also provide a progression assessment, but do not take corneal biomechanics into account. The analysis of corneal biomechanics by the Corvis ST (Oculus, Wetzlar, Germany) allows for separation of healthy and keratoconus corneas, based on the Corvis Biomechanical Index (CBI) and the Tomographic Biomechanical Index (TBI). As Corvis ST measurements are highly reliable and are independent of keratoconus severity, a biomechanical parameter was developed for keratoconus corneas based on the linear term of the CBI. This provides biomechanical keratoconus staging. The Corvis Biomechanical Factor (CBiF) is the basis for the introduction of the biomechanical E-staging, which augments the ABCD classification to the ABCDE classification, thus\n          including the cornerstone of corneal biomechanics. This article highlights strengths and limitations of the ABCDE classification. \u201cUnilateral keratoconus\u201d supposedly turns out to be mostly a snapshot of a highly asymmetric keratectasia. Regular astigmatism is sometimes an important differential diagnosis to keratectasia and may be difficult to differentiate from it. Furthermore, the use of the biomechanical E-staging in daily practice for progression assessment of keratoconus and after its treatment by corneal cross-linking or implantation of intracorneal ring segments will be demonstrated and discussed.<\/jats:p>","DOI":"10.1055\/a-2079-1740","type":"journal-article","created":{"date-parts":[[2023,6,22]],"date-time":"2023-06-22T19:19:29Z","timestamp":1687461569000},"page":"761-773","source":"Crossref","is-referenced-by-count":7,"title":["The Biomechanical E-Staging: In Vivo Biomechanics in Keratoconus"],"prefix":"10.1055","volume":"240","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0423-3624","authenticated-orcid":false,"given":"Elias","family":"Flockerzi","sequence":"additional","affiliation":[{"name":"Klinik f\u00fcr Augenheilkunde, Universit\u00e4tsklinikum des Saarlandes und Medizinische Fakult\u00e4t der Universit\u00e4t des Saarlandes, Homburg, Deutschland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9181-8913","authenticated-orcid":false,"given":"Kassandra","family":"Xanthopoulou","sequence":"additional","affiliation":[{"name":"Klinik f\u00fcr Augenheilkunde, Universit\u00e4tsklinikum des Saarlandes und Medizinische Fakult\u00e4t der Universit\u00e4t des Saarlandes, Homburg, Deutschland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cristian","family":"Munteanu","sequence":"additional","affiliation":[{"name":"Klinik f\u00fcr Augenheilkunde, Universit\u00e4tsklinikum des Saarlandes und Medizinische Fakult\u00e4t der Universit\u00e4t des Saarlandes, Homburg, Deutschland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Loay","family":"Daas","sequence":"additional","affiliation":[{"name":"Klinik f\u00fcr Augenheilkunde, Universit\u00e4tsklinikum des Saarlandes und Medizinische Fakult\u00e4t der Universit\u00e4t des Saarlandes, Homburg, Deutschland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Achim","family":"Langenbucher","sequence":"additional","affiliation":[{"name":"Institut f\u00fcr Experimentelle Ophthalmologie, Universit\u00e4tsklinikum des Saarlandes und Medizinische Fakult\u00e4t der Universit\u00e4t des Saarlandes, Homburg, Deutschland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9701-8204","authenticated-orcid":false,"given":"Berthold","family":"Seitz","sequence":"additional","affiliation":[{"name":"Klinik f\u00fcr Augenheilkunde, Universit\u00e4tsklinikum des Saarlandes und Medizinische Fakult\u00e4t der Universit\u00e4t des Saarlandes, Homburg, Deutschland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"194","published-online":{"date-parts":[[2023,6,22]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"848","DOI":"10.1080\/02713683.2018.1451545","article-title":"Asymmetry between Left and Right 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