The superficial isobaric gas counterdiffusion phenomenon, which produces dermal lesions and lethal gas embolism, was investigated at sea level and 2 ATA for effects on the eye of the New Zealand White rabbit. The animals breathed an N2O-O2 mixture by mask and were surrounded by a He environment. There was no gas lesion formation in the conjunctiva or cornea and no gas bubble formation in the anterior compartment of the eye in any of the experimental animals, even at the maximal 8-h exposure. In contrast to the eye, the skin of these animals showed progressive gas-filled lesions after 3 h at 1 ATA. Reasons for the relative insensitivity of the structures of the eye to the counter-diffusion process are discussed.