Rigid Autofluorescence Imaging as a Tool for Identifying Cholesteatoma During Otologic Surgery: Initial Ex Vivo Findings.

OBJECTIVE

This study aims to determine whether rigid autofluorescence imaging can differentiate cholesteatoma from surrounding tissues to reduce residual disease after cholesteatoma surgery.

STUDY

DESIGN

Ex vivo proof-of-principle study.

SETTING

Erasmus University Medical Center, Rotterdam, the Netherlands.

METHODS

Autofluorescence signals of cholesteatoma, mucosa, and bone were measured using confocal microscopy to confirm distinguishable spectral differences. Subsequently, rigid autofluorescence imaging with specific filter settings (λe = 405 nm and λd > 570 nm) was applied to 14 resected surgical specimens to obtain signal intensity and tissue-specific fluorescence ratios.

RESULTS

Cholesteatoma matrix without keratin exhibited a significantly higher autofluorescence intensity compared to mucosa (P < .03), with a cholesteatoma-to-mucosa ratio of 2.15. Similarly, autofluorescence intensity was elevated in the matrix with keratin (ratio: 2.25, P = .03) and perimatrix with keratin (ratio: 2.29, P = .04) relative to mucosa. Perimatrix without keratin showed a nonsignificant trend (ratio: 1.85, P = .06). Although cholesteatoma and bone showed no significant difference, this is clinically less relevant as bone is easily identifiable during surgery.

CONCLUSION

Rigid autofluorescence imaging demonstrates significant potential for improving cholesteatoma surgery by reliably differentiating cholesteatoma matrix, both with and without accumulated keratin, from mucosa, showing 2.25- and 2.15-fold higher signal intensities, respectively. This technique could assist otologic surgeons in achieving more complete resections, thereby reducing residual disease rates while preserving surrounding structures. Future research should focus on optimizing the technology for in vivo application, particularly for detecting small cholesteatoma fragments, and further evaluate factors influencing specificity and sensitivity in clinical practice.