Effect of 630-NM pulsed laser irradiation on the proliferation of HeLa cells in Photofrin(®)-mediated photodynamic therapy.

Background And Aims: Red laser light of wavelength 630 nm is usually used for Photofrin(®)-mediated photodynamic therapy (PDT). The 630-nm light employed in PDT corresponds to the region of the wavelength used in low-level laser therapy (LLLT) may influence on the photodynamic effect required for killing cancer cells. The aim of this in vitro study was to investigate the changes in cell viability and degree of cell proliferation after Photofrin(®)-mediated PDT using 630-nm pulsed laser irradiation (10 Hz repetition rate and 7-9 ns pulse width), which was clinically found to induce no remarkable cell injury.