The use of photobiomodulation therapy in the treatment of hair cycle arrest in a Pembroke Welsh corgi

Hair cycle arrest is a relatively common condition of double-coated breeds with a complex and poorly defined pathogenesis. Several therapeutic options have been described; however, the clinical response is often variable, and some treatment options can be invasive and may invoke adverse effects. Herein is described the first case of hair cycle arrest in a Pembroke Welsh corgi, which was successfully treated with photobiomodulation therapy. Photobiomodulation therapy (previously known as low-level laser therapy) proved to be a well-tolerated treatment, with no adverse effects appreciated. Videodermoscopy, a noninvasive technique, was utilised to objectively measure response to treatment and was a readily repeatable tool for in-hospital use. This case highlights a previously unrecognised breed to consider for the diagnosis of hair cycle arrest, as well a new indication for photobiomodulation therapy as a treatment option and videodermoscopy diagnostic analysis software as an aid in case management for practitioners moving forward.