Effect of suction ring application during LASIK on goblet cell density.

Purpose: To study the effect of LASIK surgery on conjunctival goblet cells as one of the proposed mechanisms for dry eye occurring after LASIK.

Methods: This prospective study included 22 eyes (11 patients) that underwent LASIK for the correction of myopia. Three pairs of samples were taken from the bulbar conjunctiva of each eye. The first pair was taken preoperatively before application of the suction ring. The second and third pairs were taken from the same sites at 1 week and 1 month consecutively. The first site was at 12 o'clock and the second at the inferotemporal quadrant between 7 and 8 o'clock. Time of suction was recorded.

Results: Preoperatively, mean goblet cell density was 424 +/- 105 cells/mm2 (range: 284 to 630 cells/mm2). All postoperative samples showed a statistically significant decrease in goblet cell count: 216 +/- 81 cells/mm2 (range: 40 to 325 cells/mm2) at 1 week and 218 +/- 99 cells/mm2 (range: 50 to 396 cells/mm2) at 1 month. Other parameters of conjunctival impression cytology were normal. The difference between the samples in the inferior conjunctiva preoperatively and 1 week postoperatively was greater than that of the superior conjunctiva. Recovery rate in both sites was similar and the damage did not correlate with the duration of suction.

Conclusions: The application of the microkeratome suction ring induced changes in the perilimbic conjunctiva. These changes contribute to the pathology of dry eye. Goblet cell count remains affected at 1 month postoperatively.