Higher percentage of CD34+ stem cells and elevated efficacy in androgenetic alopecia treatment observed in CGF prepared from 640 nm laser‐pretreated blood: A preliminary study

Background Concentrated growth factor (CGF) injection has proven effective in treating androgenetic alopecia (AGA). The primary mechanism of CGF in treating AGA is thought to be the CD34+ stem cells and platelets‐associated growth factors being injected into the scalp. CGF efficacy in treating AGA may rely on the activation level of these stem cells and platelets. The 640 nm laser is a United States Food and Drug Administration approved AGA treatment that activates follicle stem cells. Therefore, we hypothesize that pretreating CGF with a 640 nm laser may further activate CD34+ stem cells and platelets, thereby improving the efficacy of CGF in treating AGA. Objective This study aims to investigate whether 640 nm laser pretreated CGF (640CGF) has a greater effect in treating AGA than 640 nm laser non‐pretreated CGF (N640CGF) and evaluate whether 640 nm laser pretreatment changed CD34+ cell percentage. Methods This study enrolled 10 patients (8 male, 2 female) with AGA aged 18–60 years who received CGF injections. The 640CGF group was pretreated with a 640 nm laser at an energy density of 4 J/cm2, with a 30 cm irradiation distance for 30 min. Half of the scalp was treated with 640CGF, whereas the other half was treated with N640CGF. The injection was prepared by a doctor who did not know which blood tube had been pretreated. The treatment efficacy was evaluated using a trichoscope 1 month after injection. Results All 10 (100%) patients participated in the follow‐up visit, and a higher quantity of new hairs was observed on the side injected with 640CGF than N640CGF (p = 0.019). Additionally, fewer malnourished hairs were observed on the 640CGF pretreated side (p = 0.015). No serious adverse events were reported. Conclusions A higher percentage of CD34+ stem cells and improved efficacy in AGA treatment could be observed with CGF prepared from 640 nm laser‐pretreated blood.