Improving Safety: Individualized Corneal Cross-Linking Treatment For Keratoconus In Thin Corneas Via The Sub400 Protocol
Published 2024 - 42nd Congress of the ESCRS
Reference: FP18.01 | Type: Free paper | DOI: 10.82333/98d4-2064
Authors: Semra Akkaya Turhan* 1 , Elif Bagatur Vurgun 2 , Burçin Gogus 1 , Ayşe Ebru Toker 3
1Istanbul,Marmara University School of Medicine, Ophthalmology Department,Türkiye,Türkiye, 2Kocaeli,Kocaeli Kandıra M. Kazım Dinç State Hospital, Ophthalmology Department,Türkiye,Türkiye, 3Morgantown,West Virginia University Eye Institute, Department of Ophthalmology,USA,United States
Purpose
The aim of this study is to evaluate the efficacy and safety of individualized corneal cross-linking (CXL) treatment according to the Sub400 protocol in keratoconus patients with thin corneas.
Setting
Marmara University Research and Training Hospital, Department of Ophthalmology
Methods
In this prospective interventional case series, 45 eyes of 39 patients with progressive keratoconus and corneal thickness <400μm were included. Patients underwent individualized CXL treatment according to the Sub400 protocol. The best-corrected visual acuities (BCVA;LogMAR) at preoperative and postoperative 1st, 6th and 12th months, and keratometric values were compared. The depth of the demarcation line(DL) was measured by anterior segment optical coherence tomography (AS-OCT;Optovue,Fremont,CA) at postoperative 1 month, and the ratio to the central corneal thickness (CCT) was determined. Endothelial cell counts(ECC) measured with in vivo corneal confocal microscopy (IVCCM;HRT III,Heidelberg,Germany) were compared with preoperative values.
Results
Mean age of the patients was 21.8±5.4 years(range:12-36). The follow-up period was 10.2±6.3 months(range:1-20 months). In patients completing the 12-month follow-up(n=20), K1, K2 and Kmean values remained stable and significant reduction were observed in Kmax values (ΔK1=-0.5D, p=0.638; ΔK2=-0.8D, p=0.255; ΔKmean=-1.1D, p=0.326; ΔKmax=-1.6 D, p=0.003). BCVA remained stable at postoperative 1 year (0.71±0.21 vs 0.62±0.23, p=0.69). Intraoperative stromal thickness before riboflavin was measured as an average of 342.1±44.0 μm(range:203-395 μm). DL depth was measured as 196.1±33.2 μm at 1 month, and was localized to 54% of CCT. No significant difference was found between preoperative and postoperative 1-month ECC (2814±379 vs 2804±370; p=0.63).
Conclusions
The Sub400 protocol has emerged as a robust and promising approach, demonstrating both safety and efficacy in arresting the progression of keratoconus among patients with thin corneas, thereby representing a noteworthy advancement in clinical practice.