The following is true about verteporfin used in photodynamic therapy (PDT): (AIIMS Nov 2014)
|A||verteporfin is activated by green laser light|
|B||it generates free radicals which causes blood clotting local to the lesion|
|C||it destroys the new vessels through heat|
|D||it is contraindicated in pseudophakia|
Verteporfin is a liposomal benzoporphyrin derivative. It is activated by a non-thermal, red (689nm) laser light targeted specifically at the area where the CMV is located. The energy of the laser is absorbed by verteporfin, causing photochemical reactions and the generation of free radicals and singlet oxygen. These in turn cause localized cellular and tissue damage, resulting in the formation of a platelet thrombus and hence vascular occlusion of the choroidal neovascular membrane.