RESUMEN
PURPOSE: To histologically evaluate the outcome of mucous membrane grafts to the eyelid. METHODS: Case series of 31 eyes from 24 patients who underwent transplantation of hard palate (25 eyes), buccal (1 eye), or nasal turbinate (5 eyes) mucosa to the posterior eyelid surface. These grafts were biopsied at 0.5 months to 84 months (mean, 20 months) postoperatively. They were examined with light microscopy and compared with either the donor mucosa from the same patient (2 patients) or the typical donor site histology (22 patients). RESULTS: Graft biopsies revealed general epithelial morphology that was quite similar to the respective donor sites in virtually all cases. Six (25%) of 24 hard palate graft biopsies, which were obtained at 8 months to 49 months (mean, 22 months) postoperatively, displayed orthokeratosis alternating with parakeratosis, while 12 (50%) demonstrated parakeratosis alone, and another 6 (25%) showed adjacent regions of parakeratotic and nonkeratinized epithelium. No hard palate grafts showed complete absence of keratinization after transplantation. Other significant findings included loss of goblet cells in nasal turbinate grafts and few submucosal glands remaining in any specimen. CONCLUSIONS: Full-thickness mucosal grafts typically maintain their native epithelial morphology following transplantation to the ocular surface. Submucosal glands usually do not survive transplantation, which could be the result of intentional thinning of the graft at the time of transplantation. Contrary to the opinion that hard palate graft epithelium usually undergoes metaplasia from keratinized to nonkeratinized within 6 months following transplantation to the eye, all hard palate grafts in this study remained orthokeratotic and/or parakeratotic.