Although epi-keratome laser-assisted in situ keratomileusis (Epi-LASIK), penetrating keratoplasty and pars plana vitrectomy with corneal epithelial debridement for diabetic retinopathy are surgeries commonly performed, the time-sequential, in vivo microscopic wound healing process is not fully understood. The purpose of this study is to study the healing of corneal wounds after Epi-LASIK, penetrating keratoplasty and pars plana vitrectomy with corneal epithelial debridement for diabetic retinopathy by in vivo confocal microscopy, an easily performed and non-invasive procedure. We plan to enroll 40 eyes of 40 patients in each of these three surgeries. In Epi-LASIK, slit-lamp biomicroscopy, in vivo confocal microscopy, and visual acuity are recorded before and 1, 3, and 7 days after surgery. The eyes are examined weekly in the first month and at 3 and 6 months. For penetrating keratoplasty and pars plana vitrectomy with corneal epithelial debridement, slit-lamp biomicroscopy, in vivo confocal microscopy, and visual acuity are recorded before and weekly in the first month after surgeries and at 3 and 6 months. Selected images of the corneal basal/apical surface epithelia, stromal reactions and corneal endothelial conditions by in vivo confocal microscopy are evaluated qualitatively for the cellular morphology and density.