Photodynamic therapy of highly vascularized tissue

Abstract

A method for intraoperatively administering Photodynamic Therapy (PDT) to a highly vascularized target tissue. The method of PDT begins with the introduction of an exogenous photosensitizing agent into the target tissue-associated vasculature. Upon entry of the photosensitizer into the vasculature, the target tissue is immediately exposed to phototherapeutic light having a wavelength suitable for photoactivating the photosensitizer within the target tissue-associated vasculature. Continued illumination of the target tissue affects destruction of the vasculature within the tissue without requiring the photosensitizer to accumulate within the nonvascular tissue cells prior to photoactivation. The destruction of the vasculature supplying the target tissue destroys the target tissue. The method eliminates the prior art procedural step of waiting for the photosensitive compound to accumulate within the target tissue cells prior to administering photoactivating light to the target tissue. The photodynamic treatment of Dysfunctional Uterine Bleeding is presented as an example of applying the method to treat highly vascularized target tissue. The intraoperative method may be adapted for treating other tissues by increasing the amount of photosensitizer laden blood in the tissue by adjunctive means such as inducing localized vasodilator.