To investigate the effect of ocular surface reconstruction and assess the safety in cultivated oral mucosal epithelial cell sheet transplantation (COMET) regarding patients with cicatricial change of ocular surface.

Interventional study for treatment of patients with cicatricial change of ocular surface.

Single Group: (Limbal stem cell deficiency group)

Treatment: After cultivating autologous Oral mucosal epithelial cell sheet, the sheet will be transplanted to the ocular surface of the patients

Inclusion criteria

1. patient with eye which has limbal stem cell deficiency and conjunctivalization of cornea
2. patient who shows no improvement after limbal tissue or amniotic membrane transplantation, or who has difficulty in receiving long-term immunosuppressive treatment
3. patient who agree this clinical trial
4. patient with the eyes in which best corrected visual acuity is less than counting finger
5. patient who is older than sixteen year old

Exclusion criteria

1. patient who has relevant corneal transparency
2. patient who is on the pregnancy or has a plan of pregnancy within 1 year
3. patient who has corneal infection
4. patient who has diagnosis of HBV, HCV, HIV, syphilis
5. patinet who has past medial history of antinal, myocardial infarction, heart failure, arrhythmia, brain stroke, cerebrovascular disease
6. patient who has malignancy
7. patient who shows hypersensitivity to bovine protein.

Primary outcome Epithelization of corneal surface (6 months after cell sheet transplantation)

Secondary outcome Visual acuity (6 months after cell sheet transplantation)

Inclusion Criteria:

1. patient with eye which has limbal stem cell deficiency and conjunctivalization of cornea
2. patient who shows no improvement after limbal tissue or amniotic membrane transplantation, or who has difficulty in receiving long-term immunosuppressive treatment
3. patient who agree this clinical trial
4. patient with the eyes in which best corrected visual acuity is less than counting finger
5. patient who is older than sixteen year old

Exclusion Criteria:

1. patient who has relevant corneal transparency
2. patient who is on the pregnancy or has a plan of pregnancy within 1 year
3. patient who has corneal infection
4. patient who has diagnosis of HBV, HCV, HIV, syphilis
5. patinet who has past medial history of antinal, myocardial infarction, heart failure, arrhythmia, brain stroke, cerebrovascular disease
6. patient who has malignancy
7. patient who shows hypersensitivity to bovine protein.