Surgical treatment of labyrinthine fistula caused by cholesteatoma

Description of a New Labyrinthine Dehiscence: Horizontal Semicircular Canal Dehiscence at the Tympanic Segment of the Facial Nerve

Objective

This report is a case series of patients with findings suspicious for a labyrinthine dehiscence syndrome not previously described in the medical literature. We describe the clinical and test findings in 16 patients with CT findings suspicious for dehiscence of the ampullated end of the horizontal semicircular canal at the tympanic segment of the facial nerve.

Study Design

Observational case series.

Setting

Neurotology vestibular referral center.

Patients

To be included in this study the patients were seen at our center in 2019 and had a high-resolution CT scan with a collimation of 0.6 mm. Patients who were identified as having findings suspicious for dehiscence of bone where the facial nerve crosses the ampullated end of the horizontal semicircular canal (HSC-FND) were identified and further analyzed.

Interventions

Case series retrospective record review of patient symptoms, physical findings, audiometry, vestibular testing, and CT scans was performed. CT findings of other dehiscent sites were noted. A comparison to surgically treated perilymph fistula (PLF) patients of the same period was performed.

Main Outcome Measures

History and physical exam were reviewed for auditory symptoms, vestibular symptoms, and exacerbating factors. and. Audiometry and vestibular testing were reviewed to determine which tests were most likely to be abnormal. CT scans were independently graded according to degree of suspicion for HSC-FND. Finally, patients with HSC-FND as the sole dehiscence identified were compared to those who had HSC-FND plus other dehiscent sites (HSC-FND+O) and to the group of surgically treated PLF patients.

Results

Of 18 patients, 16 met inclusion criteria. Nine (56%) of those suspicious for HSC-FND had dehiscences in other parts of the labyrinth. Additional dehiscent sites included: six superior semicircular canal dehiscences (SSCD), two cochlear facial dehiscences and one cochlear carotid dehiscence. The most common auditory symptoms were autophony followed by tinnitus and aural fullness. The most common vestibular symptoms were pulsion sensation (feeling of being pushed to one side) followed by vertigo spells. The most common exacerbating factors for vertigo were straining, and sound. The most commonly abnormal vestibular test was nasal Valsalva testing, which was positive in all but one patient. Anamnesis and examination observations were similar in both groups, but the HSC-FND group were less likely to demonstrate a caloric weakness or an abnormal ECOG compared to the HSC-FND+O group. Of note, cVEMP was more often found to have lower thresholds in the HSC-FND group compared to the HSC-FND+O group. An example case is highlighted. Comparison to the PLF patients revealed statistically significant difference in the presenting symptoms of autophony, fullness and pulsion sensation. When comparing testing, HSC-FND patients were more likely to have an abnormal cVEMP and PLF patients were more likely to have asymmetric hearing. The incidence of bilateral disease was also more common among the HSC-FND patients than the PLF patients.

Conclusions

A new labyrinthine dehiscence has been described to occur where the tympanic segment of the facial nerve crosses over the ampullated end of the horizontal semicircular canal. HSC-FND patients can present in a similar manner as HSC-FND+O patients with similar test findings except as mentioned above. The identification of one dehiscence such as SSCD does not preclude the presence of another dehiscence such as HSC-FND. HSC-FND could be the source of persistent symptoms post SSCD surgery as illustrated in the case presented. HSC-FND patients seem to identify themselves compared to PLF patients by a much more likely presenting symptoms of autophony, fullness, pulsion, abnormal cVEMP, bilaterality of disease, and symmetric hearing.

Comparison of Different Slice Thicknesses in Computed Tomography for Labyrinthine Fistula Evaluation

OBJECTIVES

The aim of the present study is to assess the impact of different slice thicknesses in computed tomography for labyrinthine fistula evaluation and to determine the appropriate slice thickness.

METHODS

A total of 258 patients who underwent mastoidectomy and tympanoplasty for chronic otitis media with cholesteatoma from 2010 to 2014 were reviewed. The radiological diagnoses were compared with intraoperative findings. Sensitivity and specificity of 2.0-, 1.5-, 1.0-, and 0.75-mm-thick computed tomographic (CT) images for the evaluation of labyrinthine fistulae were calculated. Cohen's κ coefficient was also calculated.

RESULTS

The sensitivities of 2.0-, 1.5-, 1.0-, and 0.75-mm-thick CT images for the evaluation of labyrinthine fistulae were 76.9, 86.5, 90.4, and 93.3% (observer 1) and 67.3, 76.0, 79.8, and 87.5% (observer 2), respectively. The specificities of 2.0-, 1.5-, 1.0-, and 0.75-mm-thick CT images for labyrinthine fistula evaluation were 96.1, 94.8, 95.5, and 95.5% (observer 1) and 99.4, 97.4, 95.5, and 94.8% (observer 2), respectively. Cohen's κ coefficients were 0.790, 0.788, 0.876, and 0.911 in 2.0-, 1.5-, 1.0-, and 0.75-mm-thick CT images, respectively.

CONCLUSIONS

The sensitivity of CT for labyrinthine fistula evaluation increases with decreasing slice thickness, while the specificity does not improve.

A retrospective study on post-operative hearing of middle ear cholesteatoma patients with labyrinthine fistula

CONCLUSIONS

There is no significant change in bone conduction threshold after operation, so the tympanoplasty can be done to maintain hearing when conditions allow.

OBJECTIVE

To study the impact of surgical treatment on hearing of cholesteatoma patients with labyrinthine fistula.

METHODS

The clinical data of 35 patients (35 ears) with labyrinthine fistula, which were caused by cholesteatoma, were analyzed retrospectively. The hearing of 21 patients was followed up.

RESULTS

Three months to 5 years follow-up of 21 patients were accomplished by pure tone audiometry and other details. There was no recurrent cholesteatoma in the patients. Compared with pre-operative average bone conduction at 0.5, 1, 2, 4, and 8 kHz, 12 cases had a difference less than 5 dB, three patients' hearing improved (more than 10 dB), and five cases declined (more than 10 dB). One patient received cochlear implantation 3 months after the surgery. The average bone and air conduction thresholds at 0.5, 1, 2, 4, and 8 kHz had no obvious change (p > 0.05) in 11 patients managed by a canal wall down mastoidectomy with tympanoplasty.

A case of labyrinthine fistula by cholesteatoma mimicking lateral canal benign paroxysmal positional vertigo

Acute peripheral vestibulopathy, of which the chief complaint is positional vertigo, comprises benign paroxysmal positional vertigo (BPPV), labyrinthitis, labyrinthine fistula, and cerebellopontine angle tumors. Since the typical presentation of labyrinthine fistulas may be sensorineural hearing loss, positional vertigo, or disequilibrium, it is often difficult to distinguish from BPPV or Meniere's disease. Herein we report a 61-year-old female patient with typical symptoms and signs attributable to geotropic type variant of the lateral semicircular canal BPPV on the left side, who eventually was confirmed as having a labyrinthine fistula from chronic otitis media with cholesteatoma on the left side. This is another case where, even in the presence of isolated vertigo showing typical findings of acute peripheral vestibulopathy, other otologic symptoms and signs must not be overlooked.

Surgery of the ear and the lateral skull base: pitfalls and complications

Surgery of the ear and the lateral skull base is a fascinating, yet challenging field in otorhinolaryngology. A thorough knowledge of the associated complications and pitfalls is indispensable for the surgeon, not only to provide the best possible care to his patients, but also to further improve his surgical skills. Following a summary about general aspects in pre-, intra-and postoperative care of patients with disorders of the ear/lateral skull base, this article covers the most common pitfalls and complications in stapes surgery, cochlear implantation and surgery of vestibular schwannomas and jugulotympanal paragangliomas. Based on these exemplary procedures, basic "dos and don'ts" of skull base surgery are explained, which the reader can easily transfer to other disorders. Special emphasis is laid on functional aspects, such as hearing, balance and facial nerve function. Furthermore, the topics of infection, bleeding, skull base defects, quality of life and indication for revision surgery are discussed. An open communication about complications and pitfalls in ear/lateral skull base surgery among surgeons is a prerequisite for the further advancement of this fascinating field in ENT surgery. This article is meant to be a contribution to this process.

Prognostic indicators of hearing after complete resection of cholesteatoma causing a labyrinthine fistula

The objectives of this study are (1) to evaluate hearing change after complete cholesteatoma resection in the setting of a labyrinthine fistula, (2) to assess the sensitivity and specificity of the preoperative CT-scan in diagnosing a labyrinthine fistula, and (3) to determine the correlation between the type of the labyrinthine fistula and its radiologic size. A retrospective chart review of all patients operated for cholesteatoma between 2004 and 2009 was conducted. Primary outcome was defined as the average variation in bone conduction thresholds (BCTs) as well as speech discrimination score (SDS) after total excision of cholesteatoma causing a labyrinthine fistula. We reviewed all preoperative CT-scans and operative notes to assess sensitivity and specificity for the diagnosis of a labyrinthine fistula. Results show that 317 patients underwent mastoidectomy for cholesteatoma. Twenty-eight patients were found to have 32 labyrinthine fistulas caused by cholesteatomatous disease affecting the lateral semi-circular canal (SCC) (n = 25), the superior SCC (n = 5), the posterior SCC (n = 1) and the footplate (n = 1). Postoperative BCT and SDS (24.5 dB; 86.6%) were neither clinically nor statistically different from preoperative levels (23.2 dB; 87.5%) (p = 0.35). Sensitivity and specificity of the preoperative high resolution 0.55 mm cuts CT-scan was 100%. With a fistula of 3.55 mm in the axial plan, a membraneous fistula must be suspected with a sensitivity of 66% and a specificity of 71%. Complete matrix resection without suctioning at the site of a cholesteatomatous labyrinthine fistula is a safe and effective management option. High-resolution preoperative CT-scan is very precise in diagnosing labyrinthine fistula and its radiologic size helps to predict the type of the fistula.

Bilateral promontory fistula due to noncholesteatomatous chronic otitis media

The authors describe a case of bilateral promontory fistula due to noncholesteatomatous chronic otitis media in a 46-year-old male. We performed both open cavity mastoidectomy and left staged ossiculoplasty. One year postoperatively, the audiogram showed an improved left air conduction threshold and maintenance of bone conduction. We suggest that noncholesteatomatous chronic otitis media can induce various destructive changes via the chronic inflammatory reaction.