Analysis of Long-Term Change in Corneal Sensitivity after Penetrating Keratoplasty and Associated Tear Film Parameters

Abstract

Purpose:To evaluate the long-term changes in the corneal sensitivity and to analyze which tear film parameters correlate with corneal sensitivity after penetrating keratoplasty (PKP). Methods: Twenty-eight eyes of 28 patients who underwent PKP were included in the present study. Corneal sensitivity, Schirmer test, tear break-up time, tear clearance rate, and keratoepitheliopathy were evaluated at 1, 3, 6, 12, and 24 months postoperatively. Then, which tear film parameters correlated with corneal sensitivity during the follow-up period were analyzed. Results: Corneal sensitivity was 5.18 ± 3.96 mm at one month postoperatively and increased to 29.64 ± 12.39 mm (p < 0.05) at 24 months postoperatively but was still not in the normal range. Tear break-up time and keratoepitheliopathy improved at postoperative three months and six months, respectively, compared with one month postoperatively, and both measures normalized at 24 months postoperatively. Schirmer test results and tear clearance rate were in the normal range during the follow-up period. Corneal sensitivity was correlated with tear break-up time from three to 24 months postoperative and with tear clearance rate from one month to 24 months postoperative (p < 0.05). Conclusions: Change in corneal sensitivity after penetrating keratoplasty correlates with tear break-up time and tear clearance rate; therefore, tear break-up time and tear clearance rate can be used as parameters for management of dry eye after PKP.

Effect of the Preservative Benzalkonium Chloride in Prostaglandin Analogues on Corneal Sensitivity

“…14,15 피검자가 정면을 주시하도록 시선을 고정시키고 길이 60 mm, 직경 0.12 mm의 나일론 사를 각막에 수직으로 닿게 한 후 5° 이상 기울어지지 않도 록 하여 압박 시 닿는 느낌이 있을 때까지 5 mm 간격으로 나일론사의 길이를 줄여, 닿는 느낌이 있는 최초의 길이를 기록하였다. 이때 4번 자극하여 2번 이상 지각할 때의 길이…”