Academic Journal
Outcomes of the Sub400 Protocol and Contact Lens-Assisted Corneal Cross-Linking in Advanced Thin-Cornea Keratoconus: Clinical Efficacy and Long-Term Visual Stability.
| Τίτλος: | Outcomes of the Sub400 Protocol and Contact Lens-Assisted Corneal Cross-Linking in Advanced Thin-Cornea Keratoconus: Clinical Efficacy and Long-Term Visual Stability. |
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| Συγγραφείς: | Karaca EE; Department of Ophthalmology, University of Health Sciences, Ankara Bilkent City Hospital, Ankara, Turkey; and., Asfuroğlu Y; Department of Ophthalmology, Ankara Bilkent City Hospital, Ankara, Turkey., Ulusoy DM; Department of Ophthalmology, Ankara Bilkent City Hospital, Ankara, Turkey., Ustael AB; Department of Ophthalmology, University of Health Sciences, Ankara Bilkent City Hospital, Ankara, Turkey; and., Evren Kemer Ö; Department of Ophthalmology, University of Health Sciences, Ankara Bilkent City Hospital, Ankara, Turkey; and. |
| Πηγή: | Cornea [Cornea] 2026 Oct 01; Vol. 45 (10), pp. 1286-1291. Date of Electronic Publication: 2025 Oct 24. |
| Τύπος έκδοσης: | Journal Article |
| Γλώσσα: | English |
| Στοιχεία περιοδικού: | Publisher: Lippincott Williams & Wilkins Country of Publication: United States NLM ID: 8216186 Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1536-4798 (Electronic) Linking ISSN: 02773740 NLM ISO Abbreviation: Cornea Subsets: MEDLINE |
| Imprint Name(s): | Publication: Hagerstown, MD : Lippincott Williams & Wilkins Original Publication: New York, N.Y. : Masson Pub. USA, c1982- |
| Ιατρικοί όροι (MeSH): | Keratoconus*/drug therapy , Keratoconus*/physiopathology , Keratoconus*/metabolism , Keratoconus*/pathology , Keratoconus*/diagnosis , Corneal Cross-Linking*/methods , Riboflavin*/therapeutic use , Photosensitizing Agents*/therapeutic use , Visual Acuity*/physiology , Cross-Linking Reagents*/therapeutic use , Cornea*/pathology , Photochemotherapy*/methods , Contact Lenses*, Collagen/metabolism ; Corneal Stroma/metabolism ; Humans ; Retrospective Studies ; Female ; Adult ; Male ; Corneal Topography ; Ultraviolet Rays ; Young Adult ; Corneal Pachymetry ; Adolescent ; Treatment Outcome ; Follow-Up Studies |
| Περίληψη: | Purpose: To compare the clinical outcomes of the sub400 protocol and contact lens-assisted corneal cross-linking (CACXL) in patients with keratoconus with corneal thickness below 400 μm. Methods: This retrospective study included 88 eyes of 88 patients with progressive keratoconus and thinnest pachymetry <400 μm. Group 1 (n = 50) underwent sub400 CXL using individualized fluence at 3 mW/cm2, whereas group 2 (n = 38) received CACXL with 10 mW/cm2 for 9 minutes after functional pachymetry was increased above 400 μm using a riboflavin-soaked contact lens. Outcomes at 12 months included corrected distance visual acuity, keratometric parameters, thinnest corneal thickness, demarcation line (DL) depth, endothelial cell density, and progression rate. Results: Twelve months after surgery, tomographic stability was maintained in 45 of 50 eyes (90%) in the sub400 CXL group and in 33 of 38 eyes (86.8%) in the CACXL group. No eyes in both groups showed signs of endothelial decompensation. DL depth was significantly greater in the CACXL group (296.32 ± 43.22 μm) than in the sub400 group (266.44 ± 48.63 μm; P = 0.002), with a negative correlation between baseline Kmax and DL depth (ρ = -0.226, P = 0.034). No significant changes were observed in Kmax, Kmean, or postoperative thinnest corneal thickness in both groups (P > 0.05). Conclusions: Sub400 and CACXL provide similar short-term efficacy and endothelial safety in thin corneas. CACXL achieves deeper stromal penetration, although without superior 12-month visual or topographic outcomes. Longer-term studies are needed to determine whether greater DL depth yields sustained biomechanical or refractive benefits. (Copyright © 2025 Wolters Kluwer Health, LLC. All rights reserved.) |
| Competing Interests: | The authors have no funding or conflicts of interest to disclose. |
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| Contributed Indexing: | Keywords: Corneal cross linking; corneal ectasia; keratoconus; sub400 protocol |
| Substance Nomenclature: | TLM2976OFR (Riboflavin) 0 (Photosensitizing Agents) 0 (Cross-Linking Reagents) 9007-34-5 (Collagen) |
| Entry Date(s): | Date Created: 20260902 Date Completed: 20260902 Latest Revision: 20260902 |
| Update Code: | 20260903 |
| DOI: | 10.1097/ICO.0000000000004031 |
| PMID: | 42686044 |
| Βάση Δεδομένων: | MEDLINE |
| ISSN: | 1536-4798 |
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| DOI: | 10.1097/ICO.0000000000004031 |