A therapy device for providing photodynamic therapy to a target tissue, the therapy device comprising: an outer shaft extending from a proximal portion to a distal portion ; a surgical instrument translatable within the outer shaft, the surgical instrument including: a treatment end located at the distal portion configured to apply a photosensitizer and deliver phototherapeutic light to the target tissue, wherein the surgical instrument includes a lighting system to provide the phototherapeutic light and an applicator system to deliver the photosensitizer, wherein the applicator system includes: an application shaft extending from the proximal portion to an applicator tip located at the distal portion, the application shaft defining a media conduit configured to deliver the photosensitizer from a media source to the application tip , the device further including: a phototherapeutic light containment device translatable within the outer shaft wherein the phototherapeutic light containment device is in a non-expanded position when positioned within the outer shaft, and transitions from the non-expanded position to an expanded position when the phototherapeutic light containment device advances from the outer shaft, the phototherapeutic light containment device configured to contain the phototherapeutic light to a specific location defined by the phototherapeutic light containment device. an outer shaft extending from a proximal portion to a distal portion ; a surgical instrument translatable within the outer shaft, the surgical instrument including: a treatment end located at the distal portion configured to apply a photosensitizer and deliver phototherapeutic light to the target tissue, wherein the surgical instrument includes a lighting system to provide the phototherapeutic light and an applicator system to deliver the photosensitizer, wherein the applicator system includes: an application shaft extending from the proximal portion to an applicator tip located at the distal portion, the application shaft defining a media conduit configured to deliver the photosensitizer from a media source to the application tip , the device further including: a phototherapeutic light containment device translatable within the outer shaft wherein the phototherapeutic light containment device is in a non-expanded position when positioned within the outer shaft, and transitions from the non-expanded position to an expanded position when the phototherapeutic light containment device advances from the outer shaft, the phototherapeutic light containment device configured to contain the phototherapeutic light to a specific location defined by the phototherapeutic light containment device. an application shaft extending from the proximal portion to an applicator tip located at the distal portion, the application shaft defining a media conduit configured to deliver the photosensitizer from a media source to the application tip , the device further including: a phototherapeutic light containment device translatable within the outer shaft wherein the phototherapeutic light containment device is in a non-expanded position when positioned within the outer shaft, and transitions from the non-expanded position to an expanded position when the phototherapeutic light containment device advances from the outer shaft, the phototherapeutic light containment device configured to contain the phototherapeutic light to a specific location defined by the phototherapeutic light containment device. <EOS>