Laser Retinal Effects: Electrophysiological Determination in Visual Cortical Cells of Monkeys and Cats.

摘要

The purpose of the present study was to examine electrophysiologically the effect of laser induced retinal lesions on the visual cortex of mammalian animal model. The effect of threshold energy levels of laser radiation was studied acutely and chronically in cats using the visual evoked response (VER). In addition, electroretinographic (ERG) studies have been added to the program to obtain direct physiological evidence on the condition of the retinal area affected by the laser radiation. This study was coordinated with LAIR personnel (the P.I. visited two times in LAIR), especially with regard to the type of laser technology to be used and its availability in the Goldschleger Eye Institute. A Neodymium YAG laser device (Nd:YAG) was used; energy levels applied were 0.1-1.0 millijoules (mJ) and 1-100 pulses were given to the various cats. The results showed that the ERG is affected; the lased eye was less excitable than the normal eye in most of the cats studied, whatever laser energy has been applied. The findings of the visual evoked response (VER) showed that in most cats the lased eye was inferior to the normal eye. An effect was found even in cases where energy level was as small as 0.1 mJ and whether the animals were exposed to the laser radiation 1 day or 6 weeks prior to the recording session. (sdw)