Laser light absorption in the vitreous body after fluorescein angiography in diabetic patients

The presence of disodium fluorescein as a fluorescent marker in the vitreous body and also in the chorioretina, as a consequence of the administration for fluorescein angiography, influences the effectiveness of laser retinal photocoagulation on a time- and wavelength- dependent basis, in diabetic patients affected by proliferative diabetic retinopathy. In this work we discuss the problem of photocoagulation in the presence of fluorescein, from the viewpoints of (1) shielding of laser radiation by vitreous, (2) heating of the vitreous, and (3) the role of fluorescein in the chorioretina.