Changes of Tear Film and Ocular Surface with Time after Penetrating Keratoplasty

ABSTRACT

PURPOSE: To evaluate the parameters of tear function and ocular surface changes with time course after penetrating keratoplasty (PKP). METHODS: Corneal sensitivity test (CST), tear film break-up time (BUT), basal tear secretion test (BST), tear clearance test (Tcr), fluorescein staining and conjunctival impression cytology were evaluated in 21 eyes of 21 patients who underwent PKP at 1, 3 and 6 months postoperatively. RESULTS: CST (p=0.02), BST (p=0.04), fluorescein scoring (p=0.03), and goblet cell density (p=0.03) showed improving tendency during 6 month after surgery, but BUT (p=0.11), Tcr (p=0.65) and squamous metaplasia (p=0.20) did not change significantly. One month after surgery, CST (p<0.01), BUT (p=0.01), BST (p<0.01), and goblet cell density (p=0.01) were lower, while fluorescein staining score (p<0.01) and the grade of squamous metaplasia (p=0.03) were higher in PKP group. Six months after surgery, CST (p<0.01) and goblet cell density (p=0.04) were lower, and fluorescein staining score (p<0.01) was higher in PKP group. CONCLUSIONS: Tear film and ocular surface are compromised after PKP and improved gradually during postoperative 6 months. However, these parameters were not recovered completely to the normal level.