Evaluation of the efficacy and safety of cold laser (Diode 808 nm) therapy in the treatment of localized plaque psoriasis: clinical, dermoscopic and ultrastructural study

Abstract

Background Psoriasis is a chronic, recurring, and immune-mediated inflammatory skin disease. Throughout the period of the last few decades, phototherapy has become widely used in treating stable psoriatic lesions. For the treatment of psoriasis, several light/laser therapies with distinct modes of action have been developed. Cold laser therapy might be an effective therapeutic choice for localized plaque psoriasis. Objective To assess the safety and efficacy of cold laser therapy clinically and microscopically in localized plaque psoriasis treatment. Patients and methods 40 patients with localized mild plaque psoriasis were selected from the Dermatology and Venereology outpatient clinic–Tanta University Hospitals and enrolled in the clinical trial. They were treated by cold laser 808 nm wavelength (Endolaser 422, Enraf–nonious B.V. Rotterdam, Netherlands) one session for 10 min on each plaque twice weekly separated by 2 days until clinical cure or for a maximum of 8 weeks. Evaluation was done immediately after the last session by taking the average of three blinded dermatologists of the photos, the modified Psoriasis Area and Severity Index [mPASI], dermoscopic examination, patients’ satisfaction scale and histopathological and electron microscopic examination of punch biopsy specimens taken before and after the end of treatment from psoriatic lesions in four patients only. Results There was a statistically significant clinical improvement after the end of treatment compared with before treatment as 16 patients (40%) showed excellent improvement, 8 patients (20%) showed good improvement, 9 patients (22.5%) showed mild improvement, and 7 patients (17.5%) showed poor improvement. As regard mPASI, a statistically significant decrease in mPASI was found after the end of treatment ( P <0.001). Regarding dermoscopic examination, a statistically significant reduction in the percentage of patients showing dermoscopic red dots and white scales after the end of treatment ( P <0.01). As regard the patients’ satisfaction scale, 82.5% of patients were satisfied from the results. Histopathological and ultrastructural evaluation revealed normalization of the psoriatic microscopic changes with cold laser. Conclusion The use of cold laser therapy for the management of localized mild plaque psoriasis is safe, tolerable, effective, and can be used as an alternative therapy for psoriasis.