Purpose: To evaluate the role of selected modalities of Storz Professional Image Enhancement System (IMAGE1 S) in differentiating cholesteatoma during endoscopic ear surgery (EES); to assess the potential usefulness of IMAGE1 S in recognition of cholesteatoma residuals at the end of EES.
Methods: A retrospective study on 45 consecutive patients who underwent EES for cholesteatoma between March 2019 and November 2019 at a tertiary referral center was performed. For each case, Spectra A and Spectra B filters were applied intra-operatively. When examining the surgical field, a switch from white light (WL) to IMAGE1 S was performed to detect cholesteatoma and differentiate it from non-cholesteatomatous tissue. When the IMAGE1 S pattern was suspicious for the presence of cholesteatoma, images of the field under both enhancement modalities were taken and the targeted lesions were sent for histologic analysis. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of IMAGE1 S were calculated. A final recognition of the surgical field using the selected filters was performed to detect any possible cholesteatomatous residuals.
Results: Detection of cholesteatoma by IMAGE1 S selected filters revealed the following data: sensitivity 97%, specificity 95%, PPV 95%, NPV 97%. On three occasions, there was no correspondence between enhanced endoscopy and histology. In 5 out of 45 cases (11%), cholesteatoma residuals, which had not been identified at WL inspection at the end of the procedure, were detected by IMAGE1 S.
Conclusion: Our results suggest a potential role for IMAGE1 S Spectra A and B filters in EES for cholesteatoma surgery. We propose the integration of IMAGE1 S as a final overview of the surgical cavity for recognition of cholesteatomatous residuals.
Keywords: Cholesteatoma; Endoscopic ear surgery; IMAGE1 S; Image enhancement; Tympanoplasty.