{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T20:05:01Z","timestamp":1792008301521,"version":"4.4.0"},"reference-count":37,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2025,2,18]],"date-time":"2025-02-18T00:00:00Z","timestamp":1739836800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Background: Corneal allogenic intrastromal ring segments (CAIRSs) offer a novel, biocompatible alternative to synthetic intracorneal ring segments (ICRSs). This review aims to evaluate the clinical outcomes of CAIRS. Methods: Inclusion criteria were studies with a minimum of 20 eyes and six months of follow up. The primary outcome measure was uncorrected distance visual acuity (UDVA). The secondary outcomes were a change in corrected distance visual acuity (CDVA), spherical equivalent (SE), mean keratometry (K-mean), maximum keratometry (K-max), K1, K2, and pachymetry. Results: The primary outcome UDVA improved from 0.83 \u00b1 0.15 to 0.40 \u00b1 0.08 logMAR (p = 0.01), while CDVA improved from 0.52 \u00b1 0.22 to 0.19 \u00b1 0.09 logMAR (p = 0.01). K-max decreased from 57.8 \u00b1 1.09 D to 53.57 \u00b1 2.66 D (p &lt; 0.01), and K-mean reduced from 49.27 \u00b1 0.28 D to 45.30 \u00b1 1.46 D (p &lt; 0.01). An average of 84.92% \u00b1 11.4% of eyes had an improvement in UDVA. No major complications or significant visual acuity deterioration were reported. Conclusions: CAIRSs serve as an alternative to synthetic ICRSs and even corneal transplantation in some cases. They represent a safe, effective, and biocompatible promising advancement in corneal ectasia management to improve visual acuity and corneal topography with minimal complications.<\/jats:p>","DOI":"10.3390\/jcm14041340","type":"journal-article","created":{"date-parts":[[2025,2,18]],"date-time":"2025-02-18T03:47:06Z","timestamp":1739850426000},"page":"1340","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Corneal Allogenic Intrastromal Ring Segments: A Literature Review"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6817-9161","authenticated-orcid":false,"given":"Issac","family":"Levy","sequence":"first","affiliation":[{"name":"Sussex Eye Hospital, University Hospitals Sussex NHS Foundation Trust, Brighton BN2 5BF, UK"},{"name":"Ophthalmology Department, Rabin Medical Center, Petach Tikva 4941492, Israel"},{"name":"Faculty of Medicine, Tel Aviv University, Tel Aviv 6997801, Israel"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0325-6461","authenticated-orcid":false,"given":"Ritika","family":"Mukhija","sequence":"additional","affiliation":[{"name":"Sussex Eye Hospital, University Hospitals Sussex NHS Foundation Trust, Brighton BN2 5BF, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0667-3700","authenticated-orcid":false,"given":"Mayank A.","family":"Nanavaty","sequence":"additional","affiliation":[{"name":"Sussex Eye Hospital, University Hospitals Sussex NHS Foundation Trust, Brighton BN2 5BF, UK"},{"name":"Brighton & Sussex Medical School, University of Sussex, Falmer, Brighton BN1 9PX, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1796","DOI":"10.1016\/S0886-3350(01)01090-2","article-title":"Corneal ectasia induced by laser in situ keratomileusis","volume":"27","author":"Pallikaris","year":"2001","journal-title":"J. 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