Exploring Patient Pain Experiences during and after Conventional Red Light and Simulated Daylight Photodynamic Therapy for Actinic Keratosis: A Qualitative Interview Study.

Simulated daylight photodynamic therapy is a relatively new and potentially less painful alternative to conventional red light photodynamic therapy for actinic keratosis. Qualitative research exploring patient experiences of pain and skin reactions during these treatments is scarce. To address this, semi-structured interviews were conducted of 10 patients aged 60-81 years with symmetrically distributed actinic keratoses 4 weeks after split-face treatment with conventional red light photodynamic therapy and simulated daylight photodynamic therapy. The participants were recruited from an ongoing clinical randomized trial. Interviews (median length 35 min) were conducted between June 2022 and January 2023, audio-recorded, transcribed verbatim, and analysed qualitatively using content analysis, as described by Graneheim and Lundman. Participants reported that conventional red light photodynamic therapy was very painful during illumination and transiently painful in the post-treatment period, while simulated daylight photodynamic therapy was almost painless during illumination and led to minor post-treatment pain. Also, skin reactions were more intense and longer-lasting with conventional red light photodynamic therapy than with simulated daylight photodynamic therapy. Most participants expressed a treatment preference for simulated daylight photodynamic therapy but had reservations about its unestablished long-term effectiveness. This study underscores the considerable pain associated with conventional red light photodynamic therapy, and the pivotal importance of shared decision-making when selecting the most appropriate treatment.

Measurements of illuminance in simulated daylight photodynamic therapy.

BACKGROUND: Simulated daylight photodynamic therapy (SDL-PDT) is a new treatment alternative for actinic keratosis. The aim of this study was to show how the illuminance that reaches the target skin area during SDL-PDT depends on the spatial positioning of the patient. METHODS: In this technical validation study, illuminance from the SDL-PDT system IndoorLux© was measured at different angles, directions, and distances from the light sources corresponding to potential target skin areas. Using two different photometers, data from 63 measuring points at seven specific distances from the ceiling were collected at 0°, 45°, and 90° angles, respectively. Illuminance levels ≥12,000 lux were regarded as adequate. Hotspots were defined as adequate measurements in all directions at a specific measuring point at distances of 1.3, 1.5, and 1.8 m from the light sources (i.e., the most common patient treatment positions). RESULTS: Adequate illuminance levels were more common with photometer 1 (73%) than photometer 2 (57%). Almost all illuminance levels were adequate at a 0° angle with both photometers. Adequate illuminance levels were observed at 82-93% of the measuring points at a 45° angle and 22-47% at a 90° angle. Hotspots were registered with both photometers at all measuring points at 0°; 59-79% of the measuring points at 45°; and 0-21% at 90°. CONCLUSION: Patient positioning is important during SDL-PDT. Adequate illuminance is achieved if target skin areas are positioned at 0°-45° angles relative to the light sources, but not at 90° angles.

Optimizing treatment of acne with photodynamic therapy (PDT) to achieve long-term remission and reduce side effects. A prospective randomized controlled trial.

Photodynamic therapy with methyl aminolevulinate (MAL-PDT) is an effective treatment of acne vulgaris, but is associated with side effects. We performed a prospective randomized split-face study aimed at optimizing MAL-PDT treatment. Patients (n = 33) were randomized to two or four treatments of PDT with MAL on one cheek and placebo vehicle on the other cheek, 1-2 weeks apart. A 1.5-h pre-treatment with the MAL cream was followed by illumination with red light (20 J/cm2). Assessments were performed before treatment and 4, 10, and 20 weeks after the last treatment. In comparison to baseline, the number of inflammatory lesions at 20 weeks on cheeks treated with MAL-PDT showed a relative decrease of 74% in the group with two treatments and 85% in the group with four treatments. This new treatment regimen for both MAL-PDT and red-light-only PDT, with shortened pre-treatment and reduced light dose, could be an effective modality.