Photodynamic Therapy: A Clinical Consensus Guide.

BACKGROUND: The American Society of Dermatologic Surgery (ASDS) periodically develops consensus documents for its members concerning various aspects of dermatologic surgery. Advances in photodynamic therapy (PDT) have been many and PDT use has been established in a variety of skin conditions. OBJECTIVE: The ASDS board of directors proposed a committee of experts in the field to develop consensus documents on different treatments. An expert panel reviewed the literature on PDT and discussed the findings. The consensus was reached with evidence-based recommendations on different clinical applications for PDT. PATIENTS AND METHODS: This consensus document includes discussions regarding PDT, including different photosensitizers and various light source activators, historical perspective, mechanism of action, various therapeutic indications and expected outcomes, pre- and post-care, and management of adverse outcomes. RESULTS: Photodynamic therapy is highly effective for pre-cancerous lesions, superficial nonmelanoma skin cancers, inflammatory acne vulgaris and other conditions. New protocols including laser mediated PDT significantly improve results for several indications. CONCLUSION: The ASDS consensus document on PDT will be helpful for educating members on safe and effective PDT for a variety of indications.

Treatment of atrophic scars with fractionated CO2 laser facilitating delivery of topically applied poly-L-lactic acid.

BACKGROUND: Atrophic scars represent a loss of collagen and a challenging reconstructive dilemma with disappointing traditional treatments. OBJECTIVE: To study the safety and efficacy of the treatment of atrophic scars using an ablative fractionated CO2 laser and topical poly-L-lactic acid (PLLA) immediately after to improve atrophic scars. MATERIALS AND METHODS: This was an uncontrolled, institutional review board-approved, prospective study evaluating the treatment of atrophic scars. Four blinded dermatologists evaluated a total of 20 photographs taken at baseline and 3 months after the laser and PLLA treatments using the Modified Manchester Scar Scale. Four criteria were evaluated: (1) overall improvement, (2) improvement in scar atrophy, (3) improvement in scar color/dyschromia mismatch, and (4) improvement in scar contour. RESULTS: All 4 observers accurately identified 76 of the 80 "before" and "after" photographs. Therefore, the blinded evaluating physicians agreed that at the 3-month follow-up visit, 95% of the scars had improved. Each criterion demonstrated an average improvement of at least 33%. CONCLUSION: The combination of using an ablative fractional CO2 laser and PLLA in the treatment of atrophic scars has a synergistic effect on their inherent properties in up-regulating new collagen synthesis to improve atrophic scars.

Inter- and Intra-physician variation in quantifying actinic keratosis skin photodamage.

We investigated the variations in physician evaluation of skin photodamage based on a published photodamage scale. Of interest is the utility of a 10-level scale ranging from none and mild photodamage to actinic keratosis (AK). The dorsal forearms of 55 adult subjects with various amounts of photodamage were considered. Each forearm was independently evaluated by 15 board-certified dermatologists according to the Global Assessment Severity Scale ranging from 0 (less severe) to 9 (the most progressed stage of skin damage). Dermatologists rated the levels of photodamage based upon the photographs in blinded fashion. Results show substantial disagreement amongst the dermatologists on the severity of photodamage. Our results indicate that ratings could be more consistent if using a scale of less levels (5-levels or 3-levels). Ultimately, clinicians can use this knowledge to provide better interpretation of inter-rater evaluations and provide more reliable assessment and frequent monitoring of high-risk populations.

Quantifying skin photodamage with spatial frequency domain imaging: statistical results.

We investigated the change in optical properties and vascular parameters to characterize skin tissue from mild photodamage to actinic keratosis (AK) with comparison to a published photodamage scale. Multi-wavelength spatial frequency domain imaging (SFDI) measurements were performed on the dorsal forearms of 55 adult subjects with various amounts of photodamage. Dermatologists rated the levels of photodamage based upon the photographs in blinded fashion to allow comparison with SFDI data. For characterization of statistical data, we used artificial neural networks. Our results indicate that optical and vascular parameters can be used to quantify photodamage and can discriminate between the stages as low, medium, and high grades, with the best performance of ∼70%, ∼76% and 80% for characterization of low- medium- and high-grade lesions, respectively. Ultimately, clinicians can use this noninvasive approach for risk assessment and frequent monitoring of high-risk populations.

Photodynamic therapy.

Photodynamic therapy (PDT) relies on the interaction between a photosensitizer, the appropriate wavelength, and oxygen to cause cell death. First introduced about 100 years ago, PDT has continued to evolve in dermatology into a safe and effective treatment option for several dermatologic conditions. PDT is also used by pulmonologists, urologists, and ophthalmologists. This article focuses on the history of PDT, mechanism of action, photosensitizers and light sources used, therapeutic applications and expected dermatologic outcomes, as well as management of adverse events.

Skin cancer prevention in annual performance of total skin examination, photoprotection counseling, and patient instruction of self-skin examination.

BACKGROUND: Prevention of skin cancer includes early diagnosis and photoprotection, such as by physician-performed total skin examination (TSE) and patient-performed self-skin examination (SSE). Hypothesizing that 90% of our patients receive an annual TSE, photoprotection counseling, and SSE instruction, we assessed the extent to which this was documented in patients' records. We also sought to identify differences in documentation of TSE, photoprotection counseling, and instruction on SSE with or without use of a dictation template prompting documentation. MATERIALS AND METHODS: Retrospective review of a random sample of 400 patients in an outpatient dermatology practice of a tertiary care academic medical center for any dermatology appointment between May 1 and July 31, 2007. Exclusion criteria included refusal to undergo TSE, lack of access to skin (e.g., wheelchair-bound or in cast), or inappropriate visit type (e.g., for acne, psoriasis, or lupus). RESULTS: Of 400 randomly selected patients, 313 met inclusion criteria. The dictation template was used in 133; of these, 89% (119/133) had documentation in their clinical note of a TSE (exclusive of the buttocks or groin area), and 98% (130/133) had documentation of instruction on sun protection and SSE. Without use of the dictation template, these percentages dropped to 78% (140/180) and 20% (36/180), respectively. Physicians using a dictation template were more likely to document having conducted a TSE and instructed patients on photoprotection and SSE. CONCLUSIONS: A dictation template aids documentation of annual TSE and patient education efforts on photoprotection and SSE.

Comparison of the accuracy of CT volume calculated by circumscription to prolate ellipsoid volume (bidimensional measurement multiplied by coronal long axis).

RATIONALE AND OBJECTIVES: Tumor volume is one of the most important factors in evaluating the response to treatment of patients with cancer. The objective of this study was to compare computed tomographic (CT) volume calculation using a semiautomated circumscribing tracing tool (manual circumscription [MC]) to prolate ellipsoid volume calculation (PEVC; bidimensional measurement multiplied by coronal long axis) and determine which was more accurate and consistent. MATERIALS AND METHODS: The study included six patients with nine neoplasms, six phantoms, and two radiologists. The neoplasms and phantoms of varying sizes and shapes were imaged using multidetector CT scanners, with slice thicknesses ranging from 0.5 to 3 mm. Measurements were performed using a TeraRecon 3D workstation. Each lesion and phantom was manually circumscribed, and its three dimensions were measured. The measurements were repeated 2 weeks later. RESULTS: MC of the phantoms deviated from their true volumes by an average of 3.0 +/- 1%, whereas PEVC deviated by 10.1 +/- 3.99%. MC interobserver readings varied by 1.2 +/- 0.6% and PEVC by 4.8 +/- 3.3%. MC intraobserver readings varied by 1.95 +/- 1.75% and PEVC by 2.5 +/- 1.55%. Patient tumor volume predicted by MC and PEVC varied greatly; MC interobserver readings differed by 3.3 +/- 2.1% and PEVC by 20.1 +/- 10.6%. MC intraobserver readings varied by 2.5 +/- 1.9% and PEVC by 5.5 +/- 3.2%. Variability was greater for complex shapes than for simple shapes. Bidimensional analysis demonstrated an interobserver difference of 12.1 +/- 8.7% and an intraobserver difference of 5.05 +/- 3.3%. These results demonstrate large interobserver and intraobserver variability. Variability was greater for complex shapes than for simple shapes. CONCLUSION: MC of neoplasms provided more accurate and consistent volume predictions than PEVC. More complicated shapes demonstrated the superiority of MC over PEVC.