When argon laser photocoagulation is performed directly following fluorescein angiography, intense vitreous fluorescence is often apparent to the laser surgeon during each laser application. The authors created an experimental model to determine whether the surgeon is exposed to potentially toxic light levels when treating eyes containing substantial concentrations of fluorescein, such as in patients with proliferative diabetic retinopathy. Serial dilutions of sodium fluorescein using both slit lamp and indirect ophthalmoscope laser delivery systems were excited and the irradiance generated by blue-green (488, 514 nm) and green (514 nm) argon wavelengths was measured radiometrically. Maximum irradiance levels were approximately 4.5 to 6.25 times higher when sodium fluorescein was present in clinical concentrations during slit lamp delivery compared to levels measured without the presence of sodium fluorescein. When using the laser indirect ophthalmoscope, potential retinal irradiance levels were about 1/30 of those measured when a slit lamp is used. While all irradiances measured were within occupational safety guidelines, the presence of fluorescein greatly increases the laser surgeon's exposure to light despite the presence of protective safety filters.
|Original language||English (US)|
|Number of pages||5|
|Journal||Lasers and Light in Ophthalmology|
|State||Published - Jan 1 1995|
ASJC Scopus subject areas