Muscle Damage and Recovery in the Rabbit Tongue Following Photodynamic Therapy with Haematoporphyrin Derivative

To study the effects of photodynamic therapy on the tissues of the tongue. 20 New Zealand White rabbits were injected intravenously with haematoporphyrin derivative. Their tongues and those of 2 controls were illuminated with 100 J/cnr of red light from a copper vapour-pumped dye laser emitting light at 625 nm. The rabbits were sacrificed at intervals between 2 days and 12 weeks following treatment. Their tongues were examined histologically. Initially there was marked damage to mucosa, muscle and blood vessels. However, this healed by a mixture of regeneration and scarring.