Otoendoscopy in cholesteatoma surgery of the middle ear: what benefits can be expected?

OBJECTIVE: This study was conducted with the aim of determining the contribution of otoendoscopy in the surgical management of cholesteatoma of the middle ear.

BACKGROUND: The anterior epitympanum and the retrotympanum are anatomic sites that are difficult to access under otomicroscopy. Otoendoscopy offers a large field of vision using direct vision and lateral vision endoscopes, particularly in the supratubal recess and sinus tympani, for which visualization is excellent with reduced surgical approaches.The objectives of the study were to evaluate otoendoscopy as a means of identifying residues of lesions after excision of the disease under otomicroscopy in the same stage of surgery and its impact on the frequency of residual cholesteatomas at the time of surgical revision.

STUDY DESIGN: Retrospective case review.

SETTING: Private hospital center.

PATIENTS: Patients operated on a tympanoplasty under otomicroscopy with or without an otoendoscopic exploration for a cholesteatoma or an uncontrollable tympanic retraction pocket.

INTERVENTIONS: Between 1994 and 2005, 350 patients underwent tympanoplasty for a cholesteatoma or an uncontrollable tympanic retraction pocket.The surgical procedures were divided into closed tympanoplasty via the transmeatal approach, closed tympanoplasty with antroatticomastoidectomy and open tympanoplasty. Tympanoplasty was initially performed systematically under otomicroscopy.After excision of the disease, the cavities of the middle ear were examined by otovideoendoscopy, with the aim of identifying any peroperative residue of the lesion, to determine its location, especially in the epitympanum and retrotympanum, and the quality of its excision under otovideoendoscopy.During surgical revision, the frequency and location of any residual cholesteatoma were systematically recorded to determine the prognostic value of the quality of excision under otovideoendoscopy.

MAIN OUTCOME MEASURES: The repartition of the canal wall down, canal wall up, and transmeatic tympanoplasties was compared between the population operated with or without the otoendoscopy as a complementary exploration of the otomicroscopy in the same surgical time. The frequency and the location of a residual disease identified by the otoendoscopy and the frequency of a residual disease in a second surgical stage were evaluated.

RESULTS: Eighty patients (34%) who presented with an initial location of the disease at the epitympanum underwent complementary exploration by otovideoendoscopy. In this population, the frequency of open tympanoplasty was significantly lower.In 35 cases (44%), otoendoscopy revealed a residual lesion after an apparently total excision by otomicroscopy during closed tympanoplasty.The use of otoendoscopy did not produce a significant reduction in the number of residual cholesteatomas at the second stage of surgery compared to the population that underwent surgery under otomicroscopy alone. Nevertheless, the 35 residual lesions identified under otoendoscopy, as a complement to the microscope, during the first stage of surgery would have led systematically to a residual cholesteatoma at the second stage of surgery.Complementary exploration by otoendoscopy was performed on 85 patients (34%) who presented with a lesion of the retrotympanum. In this population, the frequency of open tympanoplasty was significantly reduced, while the techniques by the transmeatal approach were used in the majority of cases.In 65 cases (76%), a residual lesion was identified by otoendoscopy during the first stage of surgery in the sinus tympani or on the footplate of the stapes, between the crura of the stapes. Otoendoscopy did not produce a reduction in the frequency of residual cholesteatomas during surgical revision. Nevertheless, as for the epitympanum, the 65 residual lesions discovered under otoendoscopy would have led systematically to a residual cholesteatoma at the second stage of surgery if otoendoscopy had not been performed during the first stage.

CONCLUSION: This study confirms the real value of otoendoscopy in the surgical management of cholesteatomas of the middle ear. It belongs entirely to the minimally invasive surgical procedures, while significantly reducing the frequency of open tympanoplasty and recourse to posterior tympanotomy and offering excellent access to numerous lesions by the transmeatal approach. Analysis using otoendoscopy reduces the incidence of residual cholesteatomas by identifying lesion extensions that are overlooked under otomicroscopy. Nevertheless, some residual cholesteatomas persist at the second stage of surgery. The quality of excision under otoendoscopy constitutes an important parameter in the decision regarding revision surgery. By targeting the at-risk regions where a residual lesion was discovered, it allows the control scanner to be read with greater accuracy, thus facilitating the decision on whether to perform surgical exploration.