Objective Only preliminary investigations on the use of the 445 nanometer wavelength blue light laser (BLL) for various laryngeal pathologies have been described. Currently, no standard exists for reporting treatment technique and tissue effect with this modality. Here, we aim to establish and validate a classification system to describe laser-induced tissue effects.

Study Design Retrospective video-based study for classification development and reliability validation.

Methods Video recordings from procedures performed with the BLL by multiple academic laryngologists were retrospectively reviewed. A preliminary 6-point classification (BLL 1-6) was developed based on expert consensus. Thirteen additional procedural clips were independently rated utilizing the classification schema to assess perceived tissue effect, and measure inter- and intra-rate reliability.

Results The final 5-point classification system (BLL 1-5) included angiolysis, blanching, tissue vaporization, ablation with mechanical tissue removal, and cutting. The consensus of the combined reviewers in rating all cases was 89% (58 of 65). Complete consensus was not achieved in 11% (7/65) of cases. Of those incorrect, 57% (4/7) were of clips illustrating the BLL-2 classification. Intra-rater reliability amongst the reviewers was 100%.

Conclusion Tissue effect of the 445 nm blue light laser can reliably be standardized with this proposed classification system. This rating system can be used to facilitate future systematic study of outcomes and effective communication between laryngologists and trainees.

Y.E.B. currently receives research funding from the National Institutes of Health under grants 3OT2OD032720-01S2 and 3OT2OD032720-01S3, unrelated to the current project. All other authors declare that there is no conflict of interest.

This research was not supported by any external funding.

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Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

Ethical approval to report this study was obtained from the University of South Florida Institutional Review Board (STUDY004249), and the requirement to obtain informed consent was waived as the study was considered a review of existing data.

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Funding/Financial Support: This research was not supported by any external funding.

Statement of Disclosure of Conflicts of Interest: Y.E.B. currently receives research funding from the National Institutes of Health under grants 3OT2OD032720-01S2 and 3OT2OD032720- 01S3, unrelated to the current project. All other authors declare that there is no conflict of interest.

Ethical Statement: The authors are accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved. The study was conducted in accordance with the Declaration of Helsinki (as revised in 2013). Ethical approval to report this study was obtained from our university’s Institutional Review Board (USF IRB STUDY004249).

All data produced in the present study are available upon reasonable request to the authors.