Sudden bilateral sensorineural hearing loss associated with urticarial vasculitis.

BACKGROUND: Bilateral sensorineural hearing loss associated with recurrent urticarial skin lesions may be signs of underlying Muckle-Wells syndrome. Previous reports have described the hearing loss to be progressive in nature. METHOD: To our knowledge, this paper presents the first published case of sudden onset, bilateral sensorineural hearing loss associated with urticarial vasculitis due to underlying Muckle-Wells syndrome. RESULTS: The patient underwent a cochlear implantation with a modest outcome. CONCLUSION: Cochlear implantation may help to rehabilitate sudden hearing loss associated with this condition, but early diagnosis may allow treatment with interleukin-1ß inhibitors such as anakinra.

Discontinuity of the incudo-stapedial joint within a fully aerated middle ear and mastoid on computed tomography: A clinico-radiological study of its aetiology and clinical consequence.

AIM: To investigate the aetiology and clinical consequences of incudo-stapedial (IS) discontinuity when it is demonstrated on computed tomography (CT) within a fully aerated middle ear and mastoid. METHODS AND MATERIALS: Patients with CT evidence of IS discontinuity within a fully aerated middle ear and mastoid were prospectively identified. Clinical history, otoscopic findings, audiometry, and CT data were evaluated. Predefined criteria were used to determine the likely aetiology of IS discontinuity, whether it was diagnosed prior to the CT study, and the clinical consequences in terms of degree of conductive hearing loss and requirement for surgical correction. The range of CT appearances was evaluated. RESULTS: The IS discontinuity in 34/36 ears was felt to be due to incus erosion secondary to chronic otitis, on the basis of clinical history and otoscopic findings. The IS discontinuity was rarely evident prior to CT with long-process deficiency being identified in only 5/36 cases. The mean air bone gap was only 22.5 dB. The ossicular defect was surgically addressed in only four cases. The incus deficiency was confined to the lower-third on CT in 19/36 cases. CONCLUSION: When IS discontinuity is demonstrated within a fully aerated middle ear and mastoid, the most likely aetiology is of acquired incus erosion due to chronic otitis media. The IS discontinuity on CT is usually not evident otoscopically. It usually results in only mild conductive hearing loss and the ossicular discontinuity was rarely surgically addressed in the present series.

Magnetic resonance imaging features of large endolymphatic sac compartments: audiological and clinical correlates.

OBJECTIVES: (1) To study the prevalence and characteristics of large endolymphatic sac internal compartments on thin-section T2- and T2*-weighted magnetic resonance imaging, and to relate these to other large endolymphatic sac magnetic resonance imaging features, and (2) to correlate the compartment imaging features, endolymphatic sac size and labyrinthine anomalies with the patients' clinical and audiological data. METHOD: Magnetic resonance imaging studies for 38 patients with large endolymphatic sac anomalies were retrospectively reviewed in a tertiary referral centre. Endolymphatic sac compartment presence, morphology and imaging signal were assessed. Endolymphatic sac size and labyrinthine anomalies were also recorded. Endolymphatic sac compartments and other imaging features were correlated with clinical and audiological data. RESULTS: Compartments were present in 57 per cent of the imaged endolymphatic sacs, but their presence alone did not correlate with other imaging features or clinical data. The endolymphatic sac : internal auditory meatus signal ratio was associated with a history of sudden or fluctuating hearing loss. Hearing loss correlated with opercular and extraosseous endolymphatic sac size measurements. A larger midpoint intraosseous endolymphatic sac size was associated with clear fluid loss at cochlear implantation. CONCLUSION: The magnetic resonance imaging characteristics of large endolymphatic sac compartments have been defined. The endolymphatic sac size and distal compartment signal should be recorded, as these provide prognostic information and assist the planning of appropriate interventions.

Electric acoustic stimulation of the auditory system: experience and results of ten patients using MED-EL's M and FlexEAS electrodes.

OBJECTIVE: To evaluate the hearing preservation rate and speech perception scores in patients with profound high frequency hearing loss and acoustically aidable low frequency hearing, managed with the MED-EL electric acoustic stimulation system referenced to the insertion depth of the electrode array. STUDY DESIGN: Retrospective data analysis. PARTICIPANTS AND SETTING: Ten patients implanted at the Auditory Implant Centre, Guy's and St Thomas's Hospital, London, UK. MAIN OUTCOME MEASURES: Pure tone audiometry, speech perception tests and electrode insertion depth angle. RESULTS: Postoperatively, functional hearing preservation allowing electric acoustic stimulation was achieved in eight patients and total preservation of residual hearing in five patients with follow-up periods of more than 12 months. Three of four (75%) patients with an insertion depth of >360 degrees had a threshold shift of >25 dB, and all four patients had a threshold shift of >10 dB. All patients with total hearing preservation had the electrode inserted up to 360 degrees at maximum. Overall, speech perception outcomes increased significantly and hearing impairment was significantly reduced after electric acoustic stimulation or electric stimulation alone as compared with the preoperative scores. CONCLUSION: Electric acoustic stimulation provides significant benefit to individuals with profound high frequency hearing loss. Studies with larger number of patients are needed to establish the optimal electrode insertion angle as well as to further analyse the benefit of electric acoustic stimulation.

CT and MR imaging cochlear distance measurements may predict cochlear implant length required for a 360 degrees insertion.

BACKGROUND AND PURPOSE: A preoperative prediction of the 360 degrees point insertion depth would aid the planning of electric acoustic stimulation (EAS) implantation. The purpose of this study was to establish whether the distance between the round window and the opposite cochlear wall on CT or MR imaging may be used to predict the length of a cochlear implant electrode array required to be inserted to the 360 degrees point of the basal turn. MATERIALS AND METHODS: CT and MR imaging data were studied in 19 patients undergoing cochlear implantation. Distances were measured between the round window and the opposite outer cochlear wall on an oblique paracoronal reformatted image. Adjusted distance measurements were applied to a spiral function to estimate the length of an electrode array extending between the round window entry point and the 360 degrees point. This was compared with measurements of implant length to this insertion depth on postoperative CT. RESULTS: Intraobserver reproducibility for each of the 2 observers was r = 0.85/0.55 for CT and r = 0.87/0.67 for MR imaging. Interobserver reproducibility was r = 0.68 for CT and r = 0.84 for MR imaging. There was no bias between CT and MR imaging measurements, with a mean difference of less than 0.1 mm. CT and MR imaging estimates markedly correlated with the actual length of the electrode array extending to the 360 degrees insertion depth (SD between the estimated and actual length was 0.84 mm for CT and 0.87 mm for MR imaging). CONCLUSIONS: CT and MR imaging measures of cochlear distance (CD) were used to predict insertion depths to 360 degrees , and these were markedly concordant with the actual length of the electrode array required to reach this point. MR imaging measurements were more precise and similar in accuracy to those obtained with CT.

Effect of cochlear implant electrode insertion on middle-ear function as measured by intra-operative laser Doppler vibrometry.

HYPOTHESIS: The aim of this study was to investigate the impact of cochlear implant electrode insertion on middle-ear low frequency function in humans. BACKGROUND: Preservation of residual low frequency hearing with addition of electrical speech processing can improve the speech perception abilities and hearing in noise of cochlear implant users. Preservation of low frequency hearing requires an intact middle-ear conductive mechanism in addition to intact inner-ear mechanisms. Little is known about the effect of a cochlear implant electrode on middle-ear function. METHODS: Stapes displacement was measured in seven patients undergoing cochlear implantation. Measurements were carried out intra-operatively before and after electrode insertion. Each patient acted as his or her own control. Sound was delivered into the external auditory canal via a speaker and calibrated via a probe microphone. The speaker and probe microphone were integrated into an individually custom-made ear mould. Ossicular displacement in response to a multisine stimulus at 80 dB SPL was measured at the incudostapedial joint via the posterior tympanotomy, using an operating microscope mounted laser Doppler vibrometry system. RESULTS: Insertion of a cochlear implant electrode into the scala tympani had a variable effect on stapes displacement. In three patients, there was little change in stapes displacement following electrode insertion. In two patients, there was a significant increase, while in a further two there was a significant reduction in stapes displacement. This variability may reflect alteration of cochlear impedance, possibly due to differing loss of perilymph associated with the electrode insertion. CONCLUSION: Insertion of a cochlear implant electrode produces a change in stapes displacement at low frequencies, which may have an effect on residual low frequency hearing thresholds.

Non-sutured fixation of cochlear implants using a minimally-invasive approach.

The minimal invasive techniques have become the main stay of the surgical approach for the cochlear implant. Securing the implant with sutures can be challenging due to the limited access and awkward operating angle. We have developed a non-sutured technique to secure the implant by placing and securing the proximal end of the electrode into a bony groove. Our series supports the notion that the technique is suitable for implant cases in which the patient's age is older than 18 months.

Submucous resection of the nasal septum as an outpatient procedure.

We report our experience of submucous resection of the nasal septum under local anaesthesia as an outpatient procedure. We have audited 50 consecutive cases and compared the results with a similar group of patients in whom the operation was carried out in the usual way under general anaesthesia. We have found the procedure to be safe, effective and economically advantageous.

Does post-operative nasal packing cause nocturnal oxygen desaturation?

Previous studies have shown an increased frequency and duration of apnoeic episodes during sleep when the nose is occluded. The aim of this study was to ascertain whether oxygen desaturation occurs with nasal occlusion by post-operative packing. Continuous digital pulse oximetry was carried out before and after submucous resection of the nasal septum in 17 otherwise healthy patients. Post-operative nasal packing produced a statistically significant change in oxygen saturation during sleep. The change was, however, of such small magnitude that it is unlikely to be clinically significant.

Unterberger stepping test: a useful indicator of peripheral vestibular dysfunction?

Deviation of gait in a stepping test has been proposed as a useful indicator of peripheral labyrinthine dysfunction. A prospective study of 26 patients suspected of having uncompensated peripheral labyrinthine dysfunction and 49 normal patients with normal labyrinthine dysfunction showed no significant difference in performance of the Unterberger stepping test between patients with electronystagmographically significant canal paresis and those with normal vestibular function.

Basal lamina pathology of the utricle and endolymphatic duct in Ménière's disease.

Labyrinthectomy was performed in a patient with a 4-year history of Ménière's disease. The utricle and the proximal portion of the endolymphatic duct were studied using light and electron microscopy. The epithelium varied in height from squamous to columnar. The basal lamina lining the columnar epithelial cells showed marked thickening which was visible in the light microscope. Electron microscopy revealed that the basal lamina had a fibrillar structure. The basal lamina of adjacent blood vessels also showed pathologic thickening with similar fibrillar texture. The significance of basal lamina thickening in association with Ménière's disease is discussed.