Laser Exposures in the Maculas of Human Volunteers. I. CW HeNe, CW Argon, Pulsed Ruby Laser Measurements.
DUKE UNIV MEDICAL CENTER DURHAM N C DEPT OF OPHTHALMOLOGY
Pagination or Media Count:
Patients whose eyes require enucleation for medical reasons have been exposed to focused laser beams in a regular pattern of locations in the eye, including the macula in both the parafoveal and foveal regions. A variety of power levels have been used from ruby, continuous wave helium-neon, and continuous wave argon lasers. The ophthalmoscopic appearance of the resulting lesions has been correlated with any loss of function and with the subsequent histological examination. Other diagnostic tests such as fluorescein angiography have been used. The following effects of laser exposures in the macula were consistently seen Minimum lesions outside the fovea could not be detected functionally Suprathreshold lesions large enough to be useful as marker lesions parafoveal produced small scotomas Exposure to approximately 13 50 level for macular burns did not produce a visible lesion of the fovea, nor did it appear to have any effect on function Exposures which do not produce an alteration to the fovea visible by fundoscopy do not alter function Minimum visual lesions in the fovea may degrade vision to approximately 2040. Author Modified Abstract