Hair Density Response to Photobiomodulation in Canine Alopecia X Is Measured Reliably With an Ordinal Scale: A Randomized, Controlled, Double-Blind Study

May 2025 in “ American Journal of Veterinary Research ”

Dalia Aoudj, Jérôme R. E. del Castillo, C. Bergeron, Gabrielle Brosseau, C de Jaham, Marie‐Odile Benoit‐Biancamano, Nadia Pagé

photobiomodulation alopecia X Hair Density Score HDS histopathological analysis

TLDR Photobiomodulation did not significantly improve hair density in dogs with alopecia X.

This study assessed the impact of photobiomodulation on canine alopecia X using a 5-level ordinal Hair Density Score (HDS) in a randomized, controlled, double-blind trial with 7 dogs. The HDS demonstrated high inter-rater reliability and sensitivity to hair density changes over time, but the treatment did not significantly affect hair density compared to the sham. Histopathological analysis also showed no significant differences between treated and untreated sides. The study concludes that while the HDS is a reliable tool for monitoring hair density, further research with larger sample sizes is needed to evaluate the efficacy of photobiomodulation in treating alopecia X.

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