Figure 1. Viability of cultured ocular cells exposed to a range of verteporfin for 24 h without exposure to laser light. The percent of live cells was determined with 3-(4,5- dimethyl-2-thiazoyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay in human scleral fibroblasts (hFibro), human trabecular meshwork cells (hTMC), and a human retinal pigment epithelial cell line (ARPE-19). Data were normalized to untreated cells (0 µg/ml verteporfin; 100% Live), and plotted as the mean (n=4) with error bars representing the standard deviation. *=p<0.05 versus 0 µg/ml verteporfin treatment.