Purpose: To evaluate potential toxic effects of indocyanine green dye on cultured human retinal pigment epithelial cells.
Methods: Controlled laboratory experiment. Cultured human retinal pigment epithelial cells were exposed to balanced saline solution, balanced saline solution with endoillumination, indocyanine green or indocyanine green with endoillumination. Cells were evaluated by light microscopy, electron microscopy, and a mitochondrial dehydrogenase assay.
Results: Retinal pigment epithelial cells exposed to indocyanine green showed no histologic or ultrastructural changes. Those exposed to indocyanine green alone or indocyanine green plus light demonstrated a significant decrease in mitochondrial enzyme activity (P = 0.0002 and 0.005, respectively).
Conclusion: Brief exposure of cultured human retinal pigment epithelial cells to indocyanine green results in decreased mitochondrial enzyme activity but does not appear to influence cellular morphology or ultrastructure.