Affiliation:
1. Eye Research Center, Farabi Eye Hospital, Tehran university of Medical Sciences, Tehran, Iran
2. Ophthalmology Department, Velayat Hospital, Qazvin University of Medical Sciences, Qazvin, Iran
Abstract
Abstract
Purpose
To evaluate the 12 months' changes in tomographic, densitometric, and aberrometric parameters in keratoconic eyes after accelerated corneal cross-linking (CCL) and classify a densitometric course in different stages of the keratoconus separately (Mild, moderate, and severe).
Methods
In a prospective observational study, 67 keratoconic eyes of 67 patients that underwent accelerated epithelium-off corneal cross-linking (9 mW/cm2 and 10 minutes) for treatment of progressive keratoconus were included. Corneal tomographic, densitometric, and aberrometric values obtained using the Pentacam HR were recorded at the baseline and 3, 6, and 12 months post-operatively.
Result
One year after treatment, corrected distance visual acuity (CDVA) was improved, and maximum keratometry, thinnest pachymetry, higher order, and total Root Mean Square (RMS) were significantly decreased. (p < 0.001) Corneal densitometry values showed a significant elevation 3 months post-surgery compared to baseline and then decreases to baseline values at 1 year. Only the Anterior 0–2 mm zone densitometry at the third month was different between the three groups. RMS at 1 year correlated with Anterior 0–2 mm, Anterior 2–6 mm, total corneal 0–2 mm, and total corneal 2–6 mm densitometry values in the third month. Final CDVA at 12th-month follow-up correlated with the Anterior 0–2 mm corneal densitometry in the third month.
Conclusion
Anterior 0–2 mm zone densitometry at the third-month post accelerated CCL can be used to detect different staging of keratoconus. Due to the correlation between final aberrometric and peak densitometric values in keratoconic eyes, peak densitometric values can be used as a prognostic factor for the final visual outcomes after accelerated CCL.
Publisher
Research Square Platform LLC
Reference43 articles.
1. McGhee CN. 2008 Sir Norman McAlister Gregg lecture: 150 yearsof practical observations on the conical cornea – What have welearned? Clin Exp Ophthalmol 2009;37:16076.
2. Does ethnic origin influence the incidence or severity of keratoconus?;Pearson AR;Eye (Lond),2000
3. Topographic keratoconus is not rare in an Iranian population: The Tehran eye study;Hashemi H;Ophthalmic Epidemiol,2013
4. The corneal epithelial basement membrane: Structure, function, and disease;Torricelli AA;Invest Ophthalmol Vis Sci,2013
5. Induction of crosslinks in corneal tissue;Spoerl E;Exp Eye Res,1998