Abstract
Purpose:
We have previously described the presence of subepithelial fibrosis or transdifferentiation of keratocytes into fibroblasts or myofibroblasts in the cornea of individuals with bullous keratopathy. We have now examined the anterior corneal stroma for structural changes in bullous keratopathy patients after endothelial keratoplasty.
Methods:
Twenty-one individuals who underwent unilateral endothelial keratoplasty (DSAEK) at Yamaguchi University Hospital between November 2007 and July 2012 were enrolled to this clinical study. The subjects were divided into two groups on the basis of whether the preoperative duration of stromal edema was less than 12 months (group A: three men and seven women, with a mean age of 74.6 years) or at least 12 months (group B: five men and six women, with a mean age of 77.9 years). The structure of the anterior stroma was examined with an in vivo laser confocal microscope (Heidelberg Retina Tomography II-Rostock Corneal Module, Heidelberg Engineering) at various times after surgery.
Results:
In vivo confocal microscopy revealed anterior stromal scattering (ASS), subepithelial fibrosis, or fibroblastic-myofibroblastic transdifferentiation of keratocytes in the study subjects. Subepithelial fibrosis was detected in 3 of the 10 cases (30.0%) and 10 of the 11 cases (90.9%) in groups A and B, respectively, before surgery, in 2 (22.2%) and 8 (80.0%) cases, respectively, at 3 months, and in 1 (11.1%) and 5 (55.6%) cases, respectively, at 6 months. Fibroblastic-myofibroblastic transdifferentiation was detected in 1 (10.0%) and 8 (72.7%) cases in groups A and B, respectively, before surgery, in 0 and 3 (30.0%) cases, respectively, at 3 months, and in 0 and 1 (11.1%) case, respectively, at 6 months. ASS was detected in 10 (100%) and 11 (91.6%) cases in groups A and B, respectively, before surgery, in 3 (33.3%) and 6 (60.0%) cases, respectively, at 3 months and in 1 (11.1%) and 6 (66.7%) cases, respectively, at 6 months.
Conclusions:
Changes in anterior stromal structure similar to those apparent in bullous keratopathy patients before surgery were detected by in vivo confocal microscopy in such patients after DSAEK. Subepithelial fibrosis and ASS persisted for more than 6 months in a substantial proportion of individuals with a preoperative duration of stromal edema of less than 12 months.
Keywords: 484 cornea: stroma and keratocytes •
479 cornea: clinical science •
505 edema