Corneal biomechanics changes after femtosecond laser LASIK surgery / 国际眼科杂志(Guoji Yanke Zazhi)

ABSTRACT

AIM: To investigate the changes of corneal biomechanical indexes after femtosecond laser-assisted in situ keratomileusis ( LASIK ) , so as to provide theoretical basis for the safety study of femtosecond laser LASIK.?METHODS: Totally 85 myopia patients ( 170 eyes ) treated in our hospital from June 2014 to June 2016 were selected and underwent femtosecond laser LASIK surgery. The medical records of patients met the inclusion criteria were retrospectively analyzed. Corneal compensated intraocular pressure ( IOPcc ) and corneal resistance factor ( CRF ) , corneal hysteresis ( CH ) and Goldmann correlated to IOP value ( IOPg ) before operation, and at 3 and 6mo after surgery were measured by the ocular response analyzer, and central corneal thickness was measured by A type ultrasonic measuring instrument.?RESULTS:At postoperative 3 and 6mo, central corneal thickness was sharply lower than that before surgery, with a statistical significance ( P<0. 05 ); postoperative IOPcc, CRF, CH, IOPg and other corneal biomechanical parameters decreased distinctively, with statistical meaning ( P<0. 05 ); data at postoperative 3 and 6mo showed no evident differences ( P>0. 05 ); the cornea cutting thickness was 98. 67 ± 7. 56μm, CH and CRF variation were 3. 40 ± 0. 34mmHg, 3. 55 ± 0. 43mmHg respectively, the cornea cutting thickness was positively correlated with CH, CRF variation ( r=0. 232, 0. 254; P<0. 001).? CONCLUSION: Femtosecond laser LASIK can apparently reduce corneal thickness as well as the corneal biomechanical indexes, the data at postoperative 3mo tends to be stable.