Long-Term Changes of Corneal Biomechanical Properties After LASIK
Purpose
to investigate biomechanical changes after myopic LASIK by using the Ocular Response Analyzer
Methods
57 patients (114 eye) undergoing bilateral LASIK were study prospectively. Corneal biomechanical parameters (CH, CRF, IOPg, IOPcc) measurements were obtained with the Ocular Response Analyzer (ORA) before and after LASIK 3 months, 1 year and 2 years. The preoperative central corneal thickness, planned ablation depth were recorded. Manifest refraction spherical equivalent, CH, CRF, IOPg, IOPcc were measured preoperative and postoperative 3 months, 1 year and 2 years postoperatively
Results
Compared with preoperative baseline values, CH, CRF, IOPg, IOPcc decreased postoperatively (p<0.01). There no significant differences in CH, CRF, IOPcc, IOPg at 3 months, 1 year and 2 years postoperative. At end-point of the study, the mean change in CH and CRF (DCH, DCRF) were 1.72±1.36 mmHg and 3.09±1.31 mmHg respectively. The correlations between AD and DCH, DCRF were significant (r=0.434 and 0.448, p<0.0001)
Conclusion
Changes in CH and CRF after LASIK 2 years, suggest alteration in corneal biomechanics correlating with attempted correction. The CRF parameter may be more useful than CH parameter in assessing biomechanical changes resulting from LASIK