Abstract
Purpose: :
To evaluate long-term visual acuity as well as endothelial cell loss after endokeratoplasty in patients with endothelial disorders.
Methods: :
53 eyes of 45 patients with reduced corneal transparency due to Fuchs’ corneal dystrophy (n=38), pseudophakic bullous keratopathy (n=8), glaucoma (n=6) and trauma (n=1) underwent endokeratoplasty between June 2002 and September 2008. Endokeratoplasty is a surgical procedure where an automated microkeratome (ALTK -automated lamellar therapeutic keratoplasty system - Moria, Doylestown, Pennsylvania) is used to create a hinged corneal flap. After trephination and substitution of the underlying tissue with the donor button, prepared on the artificial anterior chamber of the ALTK system, the superficial flap is sutured back into position. Finally air is insufflated into the anterior chamber to enforce fixation and subsequently is exchanged with fluid. All surgeries were performed by one surgeon. (CS) Examinations during follow-up included best corrected visual acuity testing in snellen as well as endothelial cell count (Noncon ROBO-CA, Konan-Keeler, Kobe, Japan).
Results: :
Mean age was 70 years. Mean follow-up period for all patients was 32 months. Mean visual acuity increased from 20/100+1 at baseline to 20/40+2 after 36 months (n=27, +21 letters, p<0.001) and to 20/32-1 after 60 months of follow-up (n=10, +23 letters, p=0.009). Mean endothelial cell density decreased from 2797 cells/mm2 at baseline (donor tissue) to 1025 cells/mm2 (n=26, -63%, p<0.001) after 36 months and to 882 cells/mm2 (n=10, -68%, p<0.001) after 60 months. 4 eyes (7,5%) experienced graft failure and required reoperation with donor exchange.
Conclusions: :
Endokeratoplasty is a promising alternative to penetrating keratoplasty in patients with endothelial disorders, providing a faster wound healing and better preservation of corneal surface and thus a better rehabilitation of visual acuity. However, endothelial cell loss was significant and this surgical technique has to be compared with other recently introduced surgical techniques of posterior lamellar keratoplasty.
Keywords: transplantation • cornea: endothelium • cornea: clinical science