Reversible irritative effect of acute 2.45GHz microwave exposure on rabbit eyes--a preliminary evaluation

We have attempted to determine if there is a hazardous effect of acute microwaves at 2.45 GHz on the eye of a rabbit under lengthy exposure without anesthesia, the contralateral eye serving as a control. Unilateral eyes of 9 adult Japanese white rabbits (10-12 weeks of age) were irradiated by 2.45 GHz continuous wave (CW) microwave for 160 min. to 240 min. under restraint without anesthesia. The specific absorption rate (SAR: phantom material) was 26.5 W/kg. The corneal surface temperature increment was 3.0 degrees C for 15 min. on average. Miosis occurred in all rabbits within 15 min. Post-exposure ophthalmological signs, first detected as the effect of CW irradiation, included 1) miosis and pupillary congestion; 2) keratoleucoma and corneal edema; 3) endothelial cell detachment and floating in aqua oculi, 4) fibrinogenesis in the anterior chamber, and 5) conjunctiva edema, which disappeared one week after exposure. There was no cataract formation. The acute microwave irradiation to the rabbit eye, causing the miosis and pupillary congestion in all irradiated eyes, was the first to be detected.