Audiological characteristics and exploratory treatment of a rare condition of acute-otitis-media-associated sudden sensorineural hearing loss.

BACKGROUND: Acute otitis media (AOM) is a common disease that is more prevalent in children. Most studies concerning AOM-associated sudden sensorineural hearing loss are case reports and retrospective in nature, hence the etiology of AOM-associated sudden hearing loss has not been fully established. AIM: To analyze audiological characteristics of AOM-associated sudden hearing loss and evaluate efficacy of combined tympanostomy tube placement (TTP) and intratympanic methylprednisolone. METHODS: Eight adult patients who were diagnosed with AOM-associated sudden hearing loss and ineffectively treated by conventional medical therapy were enrolled in this study. Basic data were collected, and pure tone audiometry was performed to assess the audiological characteristics. Combination therapy with TTP and intratympanic methylprednisolone injection was given to the patients. RESULTS: Mixed or sensorineural hearing loss was observed at high frequencies (2-4 kHz). All the cases in this study were cured after TTP and intratympanic methylprednisolone. After treatment, the average hearing threshold at affected frequencies was significantly lower than those in the pretreatment group (P < 0.05) and was similar to that in the healthy ears (P > 0.05). CONCLUSION: AOM rarely induces sudden sensorineural hearing loss. Combination therapy with TTP and intratympanic methylprednisolone injection may be effective after failure of conventional medical treatment.

Clinical Analysis of Intratympanic Injection of Dexamethasone for Treating Sudden Deafness.

INTRODUCTION: A variety of causes may induce sudden deafness. However, it remains challenging to determine the exact cause in a clinic. There is no standard treatment for this disease due to its unclear etiology. OBJECTIVE: The present study aims to investigate the clinical efficacy of the intratympanic injection of dexamethasone for treating sudden deafness. METHODS: A total of 154 patients with sudden deafness were retrospectively analyzed. The evaluation of sudden deafness was based on the AAO-HNS efficacy evaluative criteria. All patients were initially treated within seven days by an intravenous drip of methylprednisolone, vasodilator, and neurotrophic agents. These patients were divided into two groups: the treatment group (91 patients) and the control group (63 patients). Patients in the treatment group were given an intratympanic injection of dexamethasone, while patients in the control group were given conventional vasodilators and neurotrophic treatment. RESULTS: The effective rate in the treatment group was 47.25% (43/91 patients), and this was significantly higher than in the control group (14.29%, 9/63 patients). The adverse reactions in the treatment group included transient pain (7.69%, 7/91), but there was no vertigo in either group. There was one case of tympanic membrane perforation. CONCLUSION: The intratympanic injection of dexamethasone is a better choice for refractory sudden deafness due to its high efficacy and fewer adverse reactions.

Case analysis of temporal bone lesions with facial paralysis as main manifestation and literature review.

OBJECTIVE: This study aims to discuss clinical characteristics, image manifestation and treatment methods of temporal bone lesions with facial paralysis as the main manifestation for deepening the understanding of such type of lesions and reducing erroneous and missed diagnosis. METHODS: The clinical data of 16 patients with temporal bone lesions and facial paralysis as main manifestation, who were diagnosed and treated from 2009 to 2016, were retrospectively analyzed. Among these patients, six patients had congenital petrous bone cholesteatoma (PBC), nine patients had facial nerve schwannoma, and one patient had facial nerve hemangioma. All the patients had an experience of long-term erroneous diagnosis. RESULTS: The lesions were completely excised by surgery. PBC and primary facial nerve tumors were pathologically confirmed. Facial-hypoglossal nerve anastomosis was performed on two patients. HB grade VI was recovered to HB grade V in one patient. The anastomosis failed due to severe facial nerve fibrosis in one patient. Hence, HB remained at grade VI. Postoperative recovery was good for all patients. No lesion recurrence was observed after 1-6 years of follow-up. CONCLUSION: For the patients with progressive or complete facial paralysis, imaging examination should be perfected in a timely manner. Furthermore, PBC, primary facial nerve tumors and other temporal bone space-occupying lesions should be eliminated. Lesions should be timely detected and proper intervention should be conducted, in order to reduce operation difficulty and complications, and increase the opportunity of facial nerve function reconstruction.

An efficient strategy for establishing a model of sensorineural deafness in rats.

Ototoxic drugs can be used to produce a loss of cochlear hair cells to create animal models of deafness. However, to the best of our knowledge, there is no report on the establishment of a rat deafness model through the combined application of aminoglycosides and loop diuretics. The aim of this study was to use single or combined administration of furosemide and kanamycin sulfate to establish rat models of deafness. The rats received intravenous injections of different doses of furosemide and/or intramuscular injections of kanamycin sulfate. The auditory brainstem response was measured to determine the hearing threshold after drug application. Immunocytochemistry and confocal microscopy were performed to evaluate inner ear morphology. In the group receiving combined administration of furosemide and kanamycin, the auditory brainstem response threshold showed significant elevation 3 days after administration, higher than that produced by furosemide or kanamycin alone. The hair cells showed varying degrees of injury, from the apical turn to the basal turn of the cochlea and from the outer hair cells to the inner hair cells. The spiral ganglion cells maintained a normal morphology during the first week after the hair cells completely disappeared, and then gradually degenerated. After 2 months, the majority of spiral ganglion cells disappeared, but a few remained. These findings demonstrate that the combined administration of furosemide and kanamycin has a synergistic ototoxic effect, and that these drugs can produce hair cell loss and hearing loss in rats. These findings suggest that even in patients with severe deafness, electronic cochlear implants may partially restore hearing.

Vibrant Soundbridge implantation via the third window in two Chinese patients with severe bilateral congenital aural atresia.

CONCLUSION: In patients with undeveloped vestibular/oval windows and inaccessible round windows, Vibrant Soundbridge (VSB) implantation performed by placing the transducer into a reconstructed window on the inner tympanum wall demonstrated significant improvement in hearing and verbal communication ability. OBJECTIVE: To report our surgical experience with new placement of the VSB in pediatric patients with undeveloped vestibular windows, inaccessible round windows, and severe bilateral congenital aural atresia (CAA). METHODS: In two patients with bilateral CAA selected for middle ear implantation, CT scans revealed severe middle ear malformation including inaccessible round windows, absence of vestibular/oval windows, and abnormal facial nerve anatomy. The transducer of the VSB was implanted into a 'window' drilled at the inner tympanum wall in both patients. RESULTS: The surgery was successful. Pure-tone air conduction thresholds across the frequencies of 0.25-8 Hz were improved by 35 dB (preoperation, 69.2 dB; postactivation, 34 dB) in patient 1 and 46.6 dB (preoperation, 75.8 dB; postactivation, 24.2 dB) in patient 2. Normal hearing thresholds were achieved in the range of 1-8 kHz in both patients. A sentence recognition rate of up to 100% (65 dB SPL in a quiet room) was attained by both patients after surgery and VSB activation at 3 months postoperatively.

In vivo delivery of Atoh1 gene to rat cochlea using a dendrimer-based nanocarrier.

Gene therapy is a promising clinical solution to hearing loss. However suitable gene carriers for the auditory system are currently unavailable. Given the unique structure of the inner ear, the route of delivery and gene transfer efficiency are still not optimal at present. This study presented a non-viral delivery system of in vivo delivery of Atoh1 gene (a potentially therapeutic gene for hearing loss) to rat cochlea. We treated polyamidoamine (PAMAM) dendrimers by activating and modifying with Na-carboxymethyl-beta-cyclodextrins (CM-beta-CD) in sequence. A novel gene carrier (CM-beta-CD modified activated PAMAM dendrimers, CMAP) was then constructed. CMAP nanoparticles could bind pRK5-Atoh1-EGFP plasmids to form vector-DNA complexes (dendriplexes) with a mean particle size of 132 +/- 20 nm and zeta potential of 31 +/- 3 mV. These dendriplexes were locally applied on the round window membrane and delivered to the inner ear by passive gradient permeation. Results showed that the Atoh1 gene was successfully transferred into the cells as indicated by the green fluorescence detected in the inner ear. A relatively selective gene transfer with high efficiency was achieved in the auditory hair cells but not much in other cell types in the cochlea. Auditory brainstem response was determined seven days after inoculation, indicating good tolerance. This approach may provide a novel tool for inner ear gene therapy and initiate the applications of biomaterials to treat auditory disorders.