In Reply: The Use of a 405-nm Blue Light System in a Neurosurgical Department as an Adjunct for Lowering Environmental Contamination and Perioperative Infections: Results From a Prospective Observational Cohort Study

To the Editor: We sincerely thank the authors for their insightful comments and their thorough discussion on our publication regarding the use of 405-nm blue light as an adjunctive tool for reducing environmental contamination and perioperative infections in the neurosurgical setting.1 We fully agree with the authors on the critical importance of preventing healthcare-associated infections, particularly in neurosurgery, given the complexity of the patients treated and the potential severity of infection-related outcomes. We appreciate their recognition of our significant results, demonstrating a reduction in surgical wound infections and environmental contamination, findings consistent with previous studies.2-4 As highlighted by Rahman and colleagues, we acknowledge the methodological limitations of our study, specifically the prospective observational design and the absence of randomization and blinding, which could introduce performance and selection biases. However, we underline that despite these potential biases, the observed infection rate reduction was significant, occurring notably although surgical procedures in the blue light ward had longer durations—a factor generally correlated with increased infection risk.3,5 These results provide further weight to the observed outcomes, suggesting the robustness of our findings against potential biases. In addition, we highlight previous controlled clinical studies which reported similar efficacy with antimicrobial light systems. Bache et al (2012), for instance, demonstrated up to 75% reduction in bacterial contamination using high-intensity narrow-spectrum (HINS) light systems, supporting our study's outcomes.2,6 We greatly appreciate the authors' suggestion for future randomized multicenter trials aimed at further validating the efficacy, cost-effectiveness, and broader applicability of blue light technology in different hospital settings, including intensive care units and transplant units. Indeed, the implementation of structured protocols for routine use of such antimicrobial light systems in the operating room setting would be a crucial step forward, enhancing standard infection control measures. In conclusion, we fully agree that antimicrobial blue light systems should be seen as a complementary measure rather than a replacement for established infection control practices, including strict adherence to aseptic protocols and instrument sterilization. We thank the authors again for their valuable comments and look forward to future collaborative studies that could further advance patient safety and the quality of care in neurosurgical departments.