Is photodynamic therapy for rejuvenation realistic?

Paris - Lasers and intense pulsed light sources (IPL) are effective for nonablative skin resurfacing of skin changes due to photoaging.

Photorejuvenation therapy combined with 20 percent 5-ALA (5-aminolevulinic acid) and IPL or lasers effect superior clinical results when compared to IPL treatment alone, proving photodynamic therapy (PDT) to be a plausible, safe and realistic therapy for skin rejuvenation, according to Peter Bjerring, M.D., Ph.D., director of the Dermatological Laser Center at The Private Hospital Molholm in Vejle, Denmark.

Dr. Bjerring spoke in detail on the effects of PDT on skin rejuvenation at the Anti-Aging Medicine World Congress, here.

More specifically, type 3 photorejuvenation is best achieved with a second-generation IPL combined with a photosensitizer. Dr. Bjerring cites a study by Dr. Tina Alster et al. in which 10 patients with mild to moderate photodamage were treated with 20 percent 5-ALA plus IPL on one side of the face and IPL alone on the contralateral side. The two treatments were delivered at four-week intervals, with clinical improvement scores determined up to six months after the final treatment.

Study results

Results of the study showed that higher clinical improvement scores were noted on the areas treated with combination 5-ALA plus IPL.

Only a mild erythema, edema and desquamation were observed on the facial halves where 5-ALA was applied without any post-procedural scarring or unwanted pigmentary changes observed. This proves that PDT with 5-ALA combined with IPL is safe and more effective for facial rejuvenation than an IPL treatment alone.

Improving treatment safety

To improve the safety of 5-ALA therapies, Dr. Bjerring and Agneta Troilius, M.D., from Sweden performed fluorescence studies with lower concentrations of the acid.

To ultimately improve its penetration into the skin, he adjusted the 5-ALA dose so that all the fluorescence was "burned away" after the light therapy.

By employing a FluoDerm (TARO) fluorescence quantification and visualization system, the investigators could detect that 32 hours after the application of 20 percent 5-ALA cream on the skin, there was a significant fluorescence and phototoxicity remaining. Dr. Bjerring says 5-ALA is an endogenous substance present in all cells and, when applied topically, it induces production of protoporphyrin IX and is a precursor of mitochondrial cytochromes.

Standard treatment

Dr. Bjerring's current standard treatment for photodynamic photorejuvenation is to first apply 0.5 percent 5-ALA in a liposomal solution (e.g., Lipoxala, Dudok Pharmacy, the Netherlands) as a sensitizer for two to three hours, and then to treat with light, namely an IPL Ellipse Flex at 525 nm to 750 nm, with two pulses for a pulse duration of 2.5 ms and a 10 ms interval between pulses.

For treatment of pre-malignant and sun-induced lesions (or type 4 photorejuvenation), the physician first establishes the diagnosis and the extent of the lesion (e.g., actinic keratoses or basal cell carcinomas). Then, he applies either a 0.5 percent 5-ALA liposomal solution or a 16 percent methyl ester of 5-ALA cream under occlusion for three hours. The PDT (37-90 J/cm² ) is then delivered to the tumor and immediate surrounding area. The induced fluorescence can be visualized with a BioCam (BioCam) or FluoDerm.

"The results we achieved using this system are noteworthy. Photorejuvenation type 2 and type 3 (with and without photodynamic therapy) induces objective, quantitative improvements in the extracellular dermal fibrous matrix. Furthermore, 5-ALA in combination with IPL (photorejuvenation type 4) is safe and effective for the removal of pre-malignant skin changes," Dr. Bjerring affirms.