Corneal sensitivity and ocular surface health in patients undergoing femtosecond LASIK retreatment for residual refraction.

PURPOSE: To assess corneal sensitivity and the ocular surface in patients undergoing primary femtosecond laser in situ keratomileusis (FS-LASIK) and those undergoing FS-LASIK retreatment under the same flap due to residual refractive error.

SETTING

Ekol Eye Hospital, Izmir, Turkey.

DESIGN

Prospective case series.

METHODS

19 patients with previous FS-LASIK who had myopic and astigmatic refractive error were included in the study group, and 19 age-matched and sex-matched patients undergoing FS-LASIK for the first time as the control group. Corneal sensitivity, Schirmer test, tear film break-up time (TBUT), Oxford grading scheme for ocular surface staining, and Ocular Surface Disease Index (OSDI) were measured preoperatively and at postoperative 1 week and 1, 3, and 6 months.

RESULTS

The mean refractive correction in the study and control groups, respectively, was 2.18 ± 0.78 diopters (D) (range: 1.00 to 3.50) and 2.76 ± 1.20 D (range: 1.00 to 4.50; P = .07). Corneal esthesiometry results in the study and control groups, respectively, were 6.10 ± 12.55 vs 9.90 ± 11.50 mm at 1 week ( P = .001), 41.95 ± 6.98 vs 45.09 ± 5.88 mm at 1 month ( P = .004), 56.09 ± 3.37 vs 56.19 ± 2.52 mm at 3 months ( P = .8), and 58.60 ± 2.01 vs 58.80 ± 1.39 mm at 6 months ( P = .5). Significant difference between the 2 groups in Schirmer test score that disappeared at postoperative 3 months and in TBUT and ocular surface staining that disappeared at 6 months, whereas the statistically significant difference in OSDI score persisted at 6 months ( P = .03) was detected.

CONCLUSIONS

Corneal surface sensitivity and ocular surface health are more impaired in patients undergoing FS-LASIK retreatment due to residual refractive error.