Photobiomodulation and Wearable Light Therapies: A Bibliometric Analysis of the Scientific Literature (1970-2025)

Background: This study aims to map the temporal evolution of light-based therapies and identify emerging technological trends in wearable photobiomodulation (PBM) devices. Materials and methods: A bibliometric analysis (1970-2025) was conducted using three major databases: Scopus, PubMed, and Web of Science. The initial dataset, consisting of 117 articles, was processed using the Bibliometrix package in R (version 4.5.0), resulting in a final set of 110 articles. The analysis followed the TALL model (Tracking, Analysis, Layout, and Learning). Results: Scientific production on phototherapeutic devices began in the early 2000s, peaking in 2024, showing a productivity pattern typical of emerging or highly specialized fields. The period 2010-2023 represents a central thematic hub in research. During this time, new light sources (OLED and QLED) enabled the development of flexible, wearable, and implantable photonic devices. In the recent period (2024-2025), light-based therapies are increasingly integrated with network-connected biosensing systems for tissues or accessories, allowing adaptive treatments and remote monitoring. However, these next-generation devices are still undergoing consolidation and scientific maturation. Conclusions: The results highlight the rapid evolution of research on light-based therapies toward more integrated and clinically validated approaches, indicating growing scientific interest in personalized wearable PBM devices.