Investigation of acute ocular damage threshold of 40 GHz millimeter wave on rabbit

Acute ocular damage threshold of 40 GHz millimeter wave (MMW) exposure was investigated. Pigmented rabbits were exposed unilaterally to 400, 300, 200 or 100 mW/cm² 40 GHz MMW for 6 minutes by a lens antenna under systemic anesthesia. Ocular changes were evaluated by slit-lamp biomicroscopy. Miosis and corneal epithelial damage except corneal stromal opacification were observed immediately after 6 min exposure to 400 mW/cm². Corneal stromal opacification and corneal epithelial damage occurred from 1 to 2 days after exposure. No miosis, but slight corneal epithelial damage was evident immediately after 6 min exposure to 300 mW/cm². This slight epithelial damage healed within 24 hours. No ocular changes were seen in the 200 mW/cm² exposure group from immediately after to 2 days after exposure upon slit-lamp examination. Acute ocular damage threshold of 40 GHz millimeter exposure was investigated using in vivo rabbit model. The ocular damage threshold of 40 GHz millimeter exposure seems to lie between 100 to 200 mW/cm² irradiation.