FUTURE DIRECTIONS
Controlled trials and cumulative clinical experience continue to redefine the spectrum of PDT applications. On the horizon are new photosensitizers and novel ways of delivering ALA. Knowledge gained from D-PDT, including less associated pain, has led to investigations in which low irradiance LED sources are used instead of conventional light sources. Advances in PDT have been accompanied by progress in imaging techniques such as confocal reflectance microscopy. Combination of the two in the future could lead to noninvasive diagnosis and delineation of cutaneous carcinomas as well as treatment and long-term evaluation.
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Photodynamic therapy for actinic keratosis of the forehead and scalp: a randomized, controlled, phase II clinical study evaluating the noninferiority of a new expedited microneedle-assisted photodynamic therapy
Light fractionation significantly improves the response
indications and specific procedural steps guided by the individual practitioner’s experience and empiric preferences. One round of topical drug plus light (administered as a single exposure or as multiple fractionated exposures) can be considered a single PDT session. A “course” or “cycle” of PDT may involve one or more individual PDT sessions separated by a set time interval. What should not be underestimated is the time and staffing necessary to provide appropriate patient counseling and education as well as intraoperative support and supervision during the light exposure phase. Consensus recommendations and guidelines from various expert groups and dermatologic societies have been published to guide the use of PDT.
Fig. 135.8 Erythema, edema, and multiple pustules 4 days after photody- namic therapy (PDT) for actinic keratoses. Topical 20% 5-aminolevulinic acid (ALA) was followed by irradiation with red light from an LED (light-emitting diode).