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Currently, most investigators directly use limbal explants to culture corneal epithelial cells. However, it has not been identified that limbal stem cells do readily migrate from the limbal explants onto culture plate or amniotic membrane carrier. In this study a cell-suspension culture system for rabbit limbal stem cells was developed and compared with the direct explant method in the aspect of stem cells content in the culture system. Rabbit limbal epithelial cells were dissociated from rabbit eyes by dispase and single cell suspension was made for cell-suspension culture. DeltaNp63 expression of cultured rabbit limbal epithelial cells by cell-suspension technique and explant technique was detected. In cell-suspension culture, isolated cell-suspension was evaluated by flow cytometric analysis for vimentin expression and residual limbal tissue after dispase treatment was examined by scanning electron microscopy. In limbal epithelial cells suspension less than 5% cells were vimentin positive. Examination of residual limbal tissue confirmed that all the limbal epithelial cells had been removed. Histological examination revealed that with cell-suspension culture the cultured epithelial cells could differentiate better than with explant technique. In cells cultured with cell-suspension, there were much more cells expressing DeltaNp63 than in explant cultured cells. In cells cultured with explants, most of DeltaNp63 labelling cells mustered around the explants, and peripheral cells on the slides were DeltaNp63 negative. These results suggested that with pure limbal epithelial cells suspension including basal cells, which could directly enter into culture system, cell-suspension culture technique was significantly superior to explant culture technique in terms of stem cells content.

OBJECTIVE: To evaluate contrast sensitivity and color vision of yellow ultraviolet (UV) intraocular len (IOL) in cataract patients. DESIGN: Randomized clinical trial. METHODS: Extracapsular cataract extraction was performed in 60 senile cataract patients. The patients were randomly assigned to receive 30 yellow UV IOLs and 30 ordinary UV IOLs. Visual acuity, contrast sensitivity, and color vision were examined up to 6 months postoperatively. RESULTS: The yellow UV IOLs showed statistically significantly higher spatial contrast sensitivity than ordinary UV IOLs in the low and middle frequencies. There was no significant difference between yellow and ordinary UV IOL in color vision. Incidences of photophobia and cyanopsia were less in patients who received the yellow UV IOLs. CONCLUSIONS: Yellow UV IOLs are preferable to ordinary UV IOLs in preserving spatial contrast sensitivity and cause less photophobia and cyanopsia in the early postoperative period.