Abstract
Purpose: :
To study the incidence and longterm outcome of corneal surface defects and intraocular pressure following trabeculectomy with intraoperative 5FU and MMC and different dosages of postoperative (postOP) 5FU.
Methods: :
A retrospective, non-randomized comparative study of 381 patients undergoing trabeculectomy with intraoperative application of either 5FU (group I, n=169) or MMC (group II, n=212). Depending on the Wuerzburg bleb classification score (WBCS) for postoperative scarring, of these 30 (group 2: n=26) patients did not receive 5FU postOP, 67 (93) received up to 7 postoperative injections of 5 mg 5FU and 72 (93) received more than 7 injections. Surface epithelial defects were routinely assessed by slitlamp microscopy and fluoresceine and intraocular pressure (IOP) was evaluated by Goldmann applanation tonometry. For statistical comparison the Kruskal-Wallis-Test and Chi-Square-test were used.
Results: :
The mean total dose of 5FU was 25,8±9,1 mg (28,4±7,5 mg) with ≤ 7 injections and 54,2±10,9 mg 5FU (51,7±11,8mg) with >7 injections. Increasing dosage of postOP 5FU induced more frequently corneal erosions in both groups. Corneal erosions were seen in controls in 16,7% (26.9%), with ≤7 injections in 55,2% (47.3%) and with >7 injections in 77,8% (59.1%). The difference between the non-5FU, the low and high dose 5FU regimen was significant in group I as well as in group II (each p<0,0001). All groups showed a reduction of IOP to a lower normal range after 12 months. Control: 22,4mmHg to 13,4mmHg (22,6mmHg to 10,5mmHg), with ≤7 injections 23,8mmHg to 12,5mmHg (25mmHg to 11,5mmHg) and with >7 injections 25mmHg to 15,9mmHg (25,1mmHg to 13,6mmHg) (p=0,147 (p= 0,935)).
Conclusions: :
Corneal epitheliopathy following trabeculectomy and postOP 5FU was dose dependent with higher doses leading to a higher incidence of corneal erosions. However 5FU-treatment of filtering blebs judged to be at high risk for scarring resulted in a similar final IOP lowering effect.
Keywords: cornea: epithelium • clinical (human) or epidemiologic studies: outcomes/complications • intraocular pressure