Post-operative hearing among patients with labyrinthine fistula as a complication of cholesteatoma using "under water technique"

Endoscopic diving technique for hearing preservation in managing labyrinth-invading cholesteatomas

PURPOSE

Complete removal of the matrix over the existing fistula in the event of an extensive cholesteatoma with labyrinth invasion can result in total deafness. This study aimed to present a novel method of underwater endoscopic labyrinth dissection using continuous steroid irrigation (CSI) and systemic steroid administration for hearing preservation.

METHODS

The endoscopic diving technique (EDT) was used to dissect semicircular canals, revealing the underwater anatomy of membranous labyrinth structures, in two cadaver temporal bones. EDT with CSI was used in three clinical cases with extensive cholesteatoma.

RESULTS

On cadaver temporal bones, the anatomy of the lateral (LSC), superior (SSC), and posterior membranous semicircular canals with their respective ampullas and common crus was documented. In the first case managed with transcanal EDT, the LSC was eroded across almost its entire length. The fallopian canal was circumferentially eroded at the second genu and part of the mastoid segment. The cholesteatoma matrix was completely removed, and the membranous LSC was preserved. In the second and third cases, we were able to remove the cholesteatoma matrix along the eroded bony semicircular canals while keeping the membranes intact. No sensorineural hearing loss was detected in the postoperative masked pure-tone audiometry at a mean follow-up time of 12 months or cholesteatoma recurrence at the follow-up imaging.

CONCLUSIONS

EDT with CSI can be safely utilized in the course of temporal bone labyrinth dissections and provides advantages during cholesteatoma removal over the eroded labyrinth on preservation of the membranous structures, and thus may help preserve cochlear function.

Presentation, Management, and Hearing Outcomes of Labyrinthine Fistula Secondary to Cholesteatoma: A Systematic Review and Meta-analysis

OBJECTIVE

The current study systematically reviewed the literature to compare auditory outcomes of patients treated for labyrinthine fistula (LF) based on characteristics of disease and surgical management.

DATABASES REVIEWED

PubMed, Scopus, Web of Science.

METHODS

Original series (at least five cases) published from 2000 reporting management and hearing results of LF secondary to cholesteatoma were included. Proportion and odds-ratio (OR) meta-analyses were conducted through inverse variance random-effects models based on logit transformation.

RESULTS

The prevalence of LF is estimated to be 7% (95% confidence interval [CI], 5-9%). Fistulae involving the lateral semicircular canal (90%; 95% CI, 87-93%) and larger than 2 mm (53%; 95% CI, 43-64%) were common, whereas membranous involvement was less frequent (20%; 95% CI, 12-30%). Complete removal of the cholesteatoma matrix overlying the LF was mostly applied. Bone conduction (BC) preservation was frequently achieved (81%; 95% CI, 76-85%); new-onset postoperative anacusis was rarely reported (5%; 95% CI, 4-8%). A higher chance of BC preservation was associated with sparing the perilymphatic space (OR, 4.67; 95% CI, 1.26-17.37) or membranous labyrinth (OR, 4.56; 95% CI, 2.33-8.93), exclusive lateral semicircular canal involvement (OR, 3.52; 95% CI, 1.32-9.38), smaller size (<2 mm; OR, 3.03; 95% CI, 1.24-7.40), and intravenous steroid infusion (OR, 7.87; 95% CI, 2.34-26.42).

CONCLUSION

LF occurs in a significant proportion of patients with cholesteatoma. In the past two decades, complete removal of the cholesteatoma matrix followed by immediate sealing has been favored, supported by the high proportion of BC preservation. Hearing preservation depends primarily on characteristics of the LF, and specific surgical strategies should be pursued. Intraoperative and postoperative intravenous steroid infusion is recommended.

Analysis of postoperative effects of different semicircular canal surgical technique in patients with labyrinthine fistulas

Objective

Different semicircular canal surgery techniques have been used to treat patients with labyrinthine fistulas caused by middle ear cholesteatoma. This study evaluated postoperative hearing and vestibular function after various semicircular canal surgeries.

Materials and methods

In group 1, from January 2008 to December 2014, 29 patients with middle ear cholesteatoma complicated by labyrinthine fistulas were treated with surgery involving covering the fistulas with simple fascia. In group 2, from January 2015 to October 2021, 36 patients with middle ear cholesteatoma complicated by labyrinthine fistulas were included. Cholesteatomas on the surface of type I labyrinthine fistulas were cleaned using the “under water technique” and capped with a “sandwich” composed of fascia, bone meal, and fascia. Cholesteatomas on the surface of type II and III fistulas were cleaned using the “under water technique,” and the labyrinthine fistula was plugged with a “pie” composed of fascia, bone meal, and fascia, and then covered with bone wax.

Results

Some patients with labyrinthine fistulas in group 1 exhibited symptoms of vertigo after surgery. In group 2 Patients with type II labyrinthine fistulas experienced short-term vertigo after semicircular canal occlusion, but no cases of vertigo were reported during long-term follow-up. “sandwich.” In patients with type II labyrinthine fistulas, the semicircular canal occlusion influenced postoperative hearing improvement. However, postoperative patient hearing was still superior to preoperative hearing.

Conclusion

The surface of type I labyrinthine fistulas should be capped by a “sandwich” composed of fascia, bone meal, and fascia. Type II and III labyrinthine fistulas should be plugged with a “pie” composed of fascia, bone meal, and fascia, covered with bone wax.

Development of semicircular canal occlusion

Surgical treatment of vertigo is performed with in-depth study of inner ear diseases. Achieving an effective control of vertigo symptoms while reducing damage to hearing and reducing surgical complications is the principle followed by scholars studying surgical modalities. Semicircular canal occlusion is aimed at treatment of partial peripheral vertigo disease and has attracted the attention of scholars because of the above advantages. This article provides a review of the origins of semicircular canal occlusion, related basic research, clinical applications, and the effects of surgery on vestibular and hearing function.

Labyrinthine Fistula in Cholesteatoma Patients: Outcomes of Partial Labyrinthectomy With “Underwater Technique” to Preserve Hearing

Labyrinthine fistula (LF) is one of the most important complications of cholesteatoma and is defined as an abnormal communication between the inner and the middle ear. This study aims to describe our experience with the partial labyrinthectomy evaluating the post-operative hearing results. Twenty-one patients who presented labyrinthine fistula in the semicircular canals were included in the present study. Hearing impairment was present in 48% of patients (10/21). A pre-operative assessment using the Gardner–Robertson hearing classification showed the following: 52%, Class I; and 48%, Class II. A post-surgical Gardner–Robertson hearing classification evidenced the following: 43%, Class I; and 57%, Class II. The presence of LF is usually considered a negative prognostic factor for hearing preservation. The key point of partial labyrinthectomy surgery is the preservation of structures, keeping them wet with Ringer's solution throughout the procedures, and not performing suction that is close to the opened LF. The bony labyrinth is drilled underwater without suction, removing the entire cholesteatoma matrix and quickly plugging the site before and after the LF. This faster plugging of the labyrinth makes it possible to preserve the peri-lymph and the endo-lymph fluid and the hearing function. This study showed that a partial labyrinthectomy is useful for maintaining serviceable hearing in patients with LF.