UV-C LED Disinfection of Flexible Rhinolaryngoscopes: Microbiological, Economic, Environmental, and Legislative...

To evaluate the microbiological efficacy of the Ray-Two ultraviolet-C (UV-C) light-emitting diode (LED) chamber for reprocessing flexible rhinolaryngoscopes in otorhinolaryngology (ORL) practice and compare its economic and ecological impacts with chemical high-level disinfection using the Tristel Trio Wipes System (TTWS).

In a prospective study at a tertiary ORL center, bacterial contamination was assessed on 20 flexible rhinolaryngoscopes immediately after routine posterior rhinoscopy and/or laryngoscopy. Paired swab samples were collected from the distal 10-12 cm shaft pre- and post-reprocessing: manual pre-cleaning with tap water followed by a 4-min UV-C LED cycle. Samples were cultured on TSA-5% sheep blood agar for 36 h at 35°C-37°C, with colony-forming units (CFUs) enumerated. Per-cycle costs and carbon footprints were calculated via life cycle assessment (ISO 14040/14044) and compared with TTWS, based on 5000 annual procedures.

Pre-reprocessing median CFUs (IQR; range) were 15 (3-27; 2 to > 200), reducing to 0 (0-0; 0-1) post-UV-C (p < 0.001; > 99% reduction; 19/20 samples sterile). UV-C per-cycle cost was €0.56 (vs. €8.32 for TTWS; 93% savings), with a carbon footprint of 6.81 g CO₂e (vs. 115.8 g; 94% reduction). Annual savings: €38,800 and 548 kg CO₂e.

The Ray-Two UV-C LED chamber achieves near-complete bacterial elimination (100% in 19/20 samples; 1 residual CFU in 1/20 samples) on flexible rhinolaryngoscopes, with superior cost-efficiency and sustainability versus TTWS. This mercury-free, point-of-care method supports greener ORL practice amid evolving EU and US state-level regulations on mercury-containing lamps, enhancing infection control without compromising efficacy.