Corneal biomechanics after refractive surgeryA comparison between surgical techniques
- Carlos Palomino
- Alfredo Castillo
- José Ángel Cristóbal
- M.ª Ángeles del Buey
- David Carmona
ISSN: 2171-4703
Año de publicación: 2011
Volumen: 2
Número: 3
Páginas: 127-130
Tipo: Artículo
Otras publicaciones en: Journal of Emmetropia: Journal of Cataract, Refractive and Corneal Surgery
Resumen
PURPOSE: To compare the effect of PRK, Lasik and femtosecond Lasik (fLasik) on the biomechanical properties of the cornea. METHODS: 120 eyes from subjects candidates for refractive surgery (75 men, 45 women, mean age 30±7 years of age) divided into three groups (PRK, Lasik and fLasik) were examined using the Ocular Response Analyzer (ORA). Corneal hysteresis (CH) and Corneal Resistance Factor (CRF) values were obtained before and after surgery. RESULTS: Average preop CH values were 10.45±1.09, 10.39±1.50 and 11.03±1.20 mmHg changing to 7.63±1.85, 7.37±1.71 and 8.83±1.44 mmHg after the surgery for the PRK, Lasik and fLasik groups respectively. A greater variability was found for both CH and CRF parameters in the PRK group, although not significantly (p>0.1). Variation was significantly greater after Lasik than fLasik (p<0.05). CONCLUSION: The least residual stromal bed the greater variation in both CH and CRF occurs, hence the greater risk of secondary keratectasia. The fLasik group maintains corneal biomechanics after the surgery better that the other groups studied, which probably accounts for the better predictability of the clinical outcomes.