Treatment of large conjunctival nevus by resection and reconstruction using amniotic membrane.

BACKGROUND: Nevus of the bulbar conjunctiva is a benign pigmented lesion of the ocular surface. Unless a biopsy is required for ruling out malignant melanoma, a nevus is usually excised for cosmetic reasons only. However, with large lesions involving two or more quadrants of the bulbar conjunctiva, a total resection can be difficult. In this report, we present a case of a huge nevus treated by surgical excision and amniotic membrane transplantation for reconstruction of the bulbar conjunctiva. METHODS: A 54-year-old Japanese man was referred to our clinic with suspected malignant tumor of the bulbar conjunctiva in his right eye. A large and diffuse pigmented tumor with numerous small cysts was present mainly on the upper bulbar conjunctiva. Resection of the conjunctival tumor and amniotic membrane transplantation for reconstruction of the bulbar conjunctiva were performed. RESULTS: The histopathological diagnosis was conjunctival nevus. Epithelialization of the bulbar conjunctiva over the amniotic membrane sheet was completed 4 weeks after resection. At 44-month follow-up, there was no recurrence or any postoperative complication. CONCLUSION: Surgical resection combined with reconstruction by amniotic membrane transplantation is effective for the treatment of large conjunctival nevus.

Alpha-internexin as a corneal autoantigen in spontaneous autoimmune keratitis mouse model.

PURPOSE: The purpose of this study was to identify target antigens of autoimmune keratitis with a disease-prone mouse model. METHODS: BALB/c nude mice grafted with embryonic rat thymi (TG nude mice) develop various organ-localized autoimmune lesions, including keratitis. A hybridoma producing a monoclonal antibody (OT-20), specific for corneal epithelium was established by using spleen cells from this model mouse of keratitis, and the target of OT-20 was identified by immunoblot analysis. Then, using the antigen, T-cell proliferation and cytokine production by TG nude mice with keratitis were examined. RESULTS: Immunoblot analysis revealed alpha-internexin to be the target antigen of OT-20 that specifically recognizes corneal epithelium. Sera from TG nude mice with keratitis reacted with alpha-internexin on Western blot analysis, and the T cells of these mice on stimulation with alpha-internexin exhibited proliferation responses and produced IL-2, IFN-gamma, and TNF-alpha, but not IL-4 or IL-5. CONCLUSIONS: These results suggest that alpha-internexin is one of the corneal antigens associated with keratitis, developing spontaneously in TG-nude mice, with a probable pathogenic role.

[Quantitative determination of vitamin A levels in frozen preserved human amniotic membrane].

PURPOSE: Retinoids are associated with cell proliferation and differentiation. The levels of retinoids (vitamin A and its derivatives) in human amniotic membrane (AM) were measured to investigate whether endogenous retinoids in AM might contribute to the process of wound healing of the keratoconjunctival epithelium in AM transplantation. SUBJECTS AND METHODS: Retinoids were extracted from AM obtained from three patients following cesarean section. Retinoids including retinol (ROL), retinylaldehyde (RAL), retinoic acid(RA), and retinyl palmitate(RP) were analyzed using a reverse-phase high performance liquid chromatograph equipped with a multi-wavelength detector or fluorescence detector. RESULTS: ROL was identified and detected in AM at a concentration of 9.42 2.75(mean +/- standard deviation) ng/g wet tissue. No other retinoids, were detected. CONCLUSION: Among the retinoids tested, only retinol was detected at low levels in human AM tissues. Based on these results, endogenous retinoids in AM probably have little effect on wound healing of the keratoconjunctival epithelium in AM transplantation.

[Corneal endothelial cell changes in triple procedure].

PURPOSE: A retrospective study was performed to examine time-related changes in the corneal endothelium in eyes that underwent a triple procedure consisting of penetrating keratoplasty, extracapsular excision, and intraocular lens (IOL) insertion. MATERIALS AND METHODS: We studied 39 eyes from 36 patients who underwent a triple procedure associated with corneal transplantation at Tokyo Medical University between February 1989 and May 1996. The ages of the patients at the time of operation ranged from 61 to 91 years (mean, 70.9 +/- 10.8 years). The postoperative follow-up period ranged from 13.6 to 107.5 months (mean, 53.4 +/- 27.1 months). The following were evaluated: 1) cure rate of transparency, 2) complications, 3) time-related changes of endothelial cell density during 7 years after operation, and 4) comparison of changes in endothelial cell density associated with various factors such as primary disease, graft, IOL, and rejection. RESULT: The following results were obtained. 1. The cure rate of transparency of the graft at the last examination(a mean of 53.4 +/- 27.1 months after surgery) was 82.1%. 2. The incidence of rejection at the last examination was 35.9%. 3. The mean endothelial cell density in the graft was 2945.8 cells/mm2 before operation, and decreased to 1806.7 cells/mm2 one year after operation, and further to 1161.1 cells/mm2 five years after operation, showing a reduction of 60.6% compared to the mean before operation. 4. The annual rate of endothelial cell reduction in the same patient was approximately 25% the first year after operation and gradually lessened from the second year, reaching a stable level of 6% after the third year. 5. The punching method(done from the epithelial side), diameter of optical zone of IOL (6 mm or less), and rejection contributed to the reduction of endothelial cell density by one year after the operation. CONCLUSION: The triple procedure is considered to be a technique that may be chosen actively.