{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T19:22:37Z","timestamp":1792783357453,"version":"4.5.0"},"reference-count":21,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T00:00:00Z","timestamp":1776297600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T00:00:00Z","timestamp":1776297600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"name":"Misr University for Science & Technology","id":[{"id":"https:\/\/ror.org\/05debfq75","id-type":"ROR","asserted-by":"crossref"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Lasers Med Sci"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>To evaluate within-group corneal biomechanical changes induced by LASIK, photorefractive keratectomy (PRK), and corneal cross-linking (CXL) using Corvis ST, while accounting for differences in baseline corneal status between refractive surgery candidates and keratoconic eyes. This prospective comparative study included 150 eyes of 150 patients undergoing LASIK (n\u2009=\u200950), PRK (n\u2009=\u200950), or epithelium-off CXL for keratoconus (n\u2009=\u200950). Corneal biomechanical parameters were assessed preoperatively and at 6\u00a0months postoperatively using Corvis ST, including deformation amplitude (DA), stiffness parameter at first applanation (SP-A1), DA ratio at 2\u00a0mm, Ambr\u00f3sio relational thickness horizontal (ARTh), corneal biomechanical index (CBI), and tomographic biomechanical index (TBI), the latter derived from combined Pentacam tomography and Corvis ST measurements. Within-group changes were analyzed using paired parametric or non-parametric tests as appropriate. Between-group comparisons were performed using ANCOVA or linear mixed-effects models adjusted for baseline values, age, central corneal thickness, and biomechanically corrected intraocular pressure. LASIK and PRK eyes demonstrated significant postoperative increases in DA, DA ratio at 2\u00a0mm, CBI, and TBI, along with significant reductions in SP-A1 and ARTh (all p\u2009&lt;\u20090.001), indicating biomechanical weakening relative to their preoperative state. The magnitude of weakening was greater following LASIK than PRK after baseline adjustment. In contrast, keratoconic eyes treated with CXL showed significant reductions in DA, DA ratio, CBI, and TBI, and a significant increase in SP-A1 (p\u2009&lt;\u20090.001), consistent with biomechanical stiffening. These changes occurred despite differing baseline biomechanical profiles between groups. LASIK and PRK are associated with measurable corneal biomechanical weakening, whereas CXL induces biomechanical stiffening in keratoconic corneas. These findings should be interpreted within the context of distinct baseline corneal conditions rather than as direct comparisons of procedural efficacy. Corvis ST provides a robust framework for quantifying procedure-specific biomechanical directionality within different clinical settings.<\/jats:p>","DOI":"10.1007\/s10103-026-04858-9","type":"journal-article","created":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T00:57:49Z","timestamp":1776301069000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Assessment of corneal biomechanical properties using Corvis ST following LASIK, PRK, and CXL"],"prefix":"10.1007","volume":"41","author":[{"given":"Passant Sayed","family":"Saif","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohamed Yasser Sayed","family":"Saif","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hisham Mohamed Khairy","family":"Abdel Dayem","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammed Othman AbdElkhalek","family":"Elsayed","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohamed Abdel Mongey","family":"Ibrahim","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,4,16]]},"reference":[{"issue":"1","key":"4858_CR1","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1007\/s00417-023-06207-w","volume":"262","author":"Y Shen","year":"2024","unstructured":"Shen Y, Zhang Y, Li C, Wang J, Zhou X (2024) The role of corneal biomechanics in refractive surgery: a clinical perspective. Graefes Arch Clin Exp Ophthalmol 262(1):33\u201342","journal-title":"Graefes Arch Clin Exp Ophthalmol"},{"issue":"1","key":"4858_CR2","volume":"10","author":"H Matalia","year":"2023","unstructured":"Matalia H, Shetty R, Roy AS, Ghosh A (2023) Insights into corneal biomechanics using Corvis ST: current and emerging applications. Bioengineering 10(1):87","journal-title":"Bioengineering"},{"key":"4858_CR3","volume":"14","author":"T Ye","year":"2024","unstructured":"Ye T, Chen X, Zhang L, Hu Y (2024) Reliability of corneal biomechanical indices using Corvis ST in healthy eyes. Sci Rep 14:17765","journal-title":"Sci Rep"},{"issue":"9","key":"4858_CR4","volume":"12","author":"R Kandavel","year":"2023","unstructured":"Kandavel R, Ameen S, Patel H, Rajesh R, Thomas J (2023) Corneal biomechanical response after LASIK and PRK using Corvis ST. J Clin Med 12(9):1156","journal-title":"J Clin Med"},{"issue":"2","key":"4858_CR5","first-page":"145","volume":"72","author":"Y Liu","year":"2024","unstructured":"Liu Y, Sharma A, Gupta R, Mehta R (2024) Evaluation of biomechanical properties in post-LASIK corneas. Indian J Ophthalmol 72(2):145\u2013152","journal-title":"Indian J Ophthalmol"},{"key":"4858_CR6","volume":"12","author":"A Elmassry","year":"2024","unstructured":"Elmassry A, Khalil A, Soliman T, Fekry S, Amin M (2024) Comparative biomechanical analysis of LASIK and PRK with and without adjunctive cross-linking using Corvis ST. Front Bioeng Biotechnol 12:1323612","journal-title":"Front Bioeng Biotechnol"},{"issue":"1","key":"4858_CR7","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1007\/s40123-023-00823-9","volume":"13","author":"C Zhang","year":"2024","unstructured":"Zhang C, Liu X, Huang Y, Feng Y (2024) Long-term biomechanical strengthening of the cornea after CXL in keratoconus patients. Ophthalmol Ther 13(1):23\u201334","journal-title":"Ophthalmol Ther"},{"key":"4858_CR8","volume":"14","author":"W Wang","year":"2024","unstructured":"Wang W, Xu H, Zhang Y, Sun Y, Tang S (2024) Visual and biomechanical outcomes of LASIK Xtra and PRK Xtra: a randomized comparative study. Sci Rep 14:21345","journal-title":"Sci Rep"},{"issue":"5","key":"4858_CR9","first-page":"321","volume":"33","author":"CJ Roberts","year":"2017","unstructured":"Roberts CJ, Dupps WJ Jr, Roberts JA (2017) Corneal biomechanics after LASIK and PRK: a comparative study. J Refract Surg 33(5):321\u2013327","journal-title":"J Refract Surg"},{"issue":"2","key":"4858_CR10","first-page":"123","volume":"28","author":"AJ Kanellopoulos","year":"2012","unstructured":"Kanellopoulos AJ, Asimellis G (2012) Comparison of corneal thickness changes after LASIK and PRK. J Refract Surg 28(2):123\u2013129","journal-title":"J Refract Surg"},{"issue":"3","key":"4858_CR11","first-page":"e0283456","volume":"19","author":"W Chen","year":"2024","unstructured":"Chen W, Bao FJ, Roberts CJ, Zhang J, Wang C, Li XF et al (2024) Effect of corneal cross-linking on biomechanical changes following transepithelial photorefractive keratectomy and femtosecond laser-assisted LASIK. PLoS ONE 19(3):e0283456","journal-title":"PLoS ONE"},{"key":"4858_CR12","doi-asserted-by":"crossref","unstructured":"Eid MZ, Sobhy AM, Abdelaziz AM (2022) Corneal biomechanical changes after laser-assisted in situ keratomileusis (LASIK), femtosecond LASIK and photorefractive keratectomy (PRK). 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J Cataract Refract Surg 42(6):879\u2013885","journal-title":"J Cataract Refract Surg"},{"issue":"Geriatric Ophth","key":"4858_CR19","doi-asserted-by":"publisher","first-page":"19","DOI":"10.21608\/niles.2021.50547.1041","volume":"4","author":"AE Abd elghany","year":"2021","unstructured":"Abd elghany AE, Haroun H, Aboud S (2021) Evaluation of corneal biomechanics in primary open angle glaucoma. Niles J Geriatr Gerontol 4(Geriatric Ophthalmology):19\u201328","journal-title":"Niles J Geriatr Gerontol"},{"key":"4858_CR20","doi-asserted-by":"publisher","DOI":"10.1038\/s41598-025-14330-3","volume":"15","author":"PS Saif","year":"2025","unstructured":"Saif PS, Okasha MG, Mahmoud H et al (2025) Impact of veriflex and ICL on corneal biomechanics and endothelial cell density. 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J Refract Surg 34(6):393\u2013399","journal-title":"J Refract Surg"}],"container-title":["Lasers in Medical Science"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s10103-026-04858-9.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/article\/10.1007\/s10103-026-04858-9","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1007\/s10103-026-04858-9.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,16]],"date-time":"2026-06-16T22:08:12Z","timestamp":1781647692000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1007\/s10103-026-04858-9"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,4,16]]},"references-count":21,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2026,12]]}},"alternative-id":["4858"],"URL":"https:\/\/doi.org\/10.1007\/s10103-026-04858-9","relation":{},"ISSN":["1435-604X"],"issn-type":[{"value":"1435-604X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,4,16]]},"assertion":[{"value":"1 October 2025","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"9 March 2026","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"16 April 2026","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"This study was conducted in accordance with the ethical standards of the Declaration of Helsinki. Ethical approval was obtained from the Faculty of Medicine Research Ethical Committee, Beni-Suef University (approval no. FMBSUREC\/05012025\/SAIF). All participants provided written informed consent prior to inclusion in the study and were informed of their right to withdraw from the study at any time.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethics approval and consent to participate"}},{"value":"Not applicable, as no identifying patient information or images were included in this study.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"Clinical trial registration:\n                      ClinicalTrials.gov\n                      Identifier: NCT06818461. Registration date: April 2024.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Clinical trial registration"}},{"value":"The authors declare no competing interests.","order":5,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"73"}}