High-Intensity Focused Ultrasound Application to the Scalp to Improve Androgenetic Alopecia in an Adult Woman

Androgenetic alopecia (AGA) is an ordinary type of hair loss that affects both men and women. Diverse treatment modalities have been developed and performed to improve AGA, and recently, energy-based devices (EBDs), including low-level laser therapy (LLLT) and fractional radiofrequency (FRF), also joined the ranks of AGA treatment. High-intensity focused ultrasound (HIFU) is one of the noninvasive EBDs and can apply a focal stimulation to the target region, putatively inducing different bioreactions in tissues and cells like LLLT and FRF. However, regarding HIFU treatment for hair loss or AGA, the authors' understanding is significantly limited. Accordingly, this case study was conducted to examine the possibility of HIFU-driven AGA treatment. HIFU was irradiated to the affected areas on the scalp (250–300 shots per session) along with hair gel (10–16 mL per session) in a female AGA patient, and a total of 6 sessions were carried out for 24 weeks. The visual observation revealed that the overall hair condition of the patient had much improved at the seventh visit (>90%) compared with baseline. Notably, the quantitative assessment demonstrated that the hair density increased up to 115 hairs/cm 2 at the sixth visit, and the hair loss area (1.3 cm diameter) gradually declined and then completely disappeared at the seventh visit. Regarding safety, there were no adverse events and almost no pain during the study period. Therefore, these results indicate that HIFU is highly effective and safe in AGA treatment, implying that HIFU can be another option for AGA. Further studies are currently warranted to elucidate detailed mechanisms of how HIFU improves AGA or other types of hair loss.