ABSTRACT
Although photodynamic therapy (PDT) has been studied intensively for the past decade, there are relatively few data on the effects on normal tissue. PDT is used predominantly to treat solid, localized tumors, the photosensitizer being activated by light from a laser. The potential for PDT in the bladder is to treat multifocal carcinoma in situ or dysplasia. The major problem that has been encountered clinically is the level of complications, in particular, the reduction in bladder capacity and compliance, most likely owing to some fibrosis in normal muscle. The mechanical strength of soft tissues is maintained predominantly by collagen, and structural integrity is vital if safe healing is to occur after tumor destruction. The effects of PDT on a range of normal tissues have been studied to ensure that safe healing is possible. Histological studies of the healing of tissues after PDT and thermal damage have demonstrated differences.
