自身免疫性感音神经性聋

自身免疫性感音神经性聋(autoimmune sensorineural hearing loss,ASNHL)是侵犯耳蜗[1、2]及蜗后[3]的自身免疫性疾病,这一概念由美国学者McCabe在1979年     

Reversible sensorineural hearing loss

We present an unusual case of temporary sensorineural hearing loss in a 6-year-old child due to carbon monoxide. This was shown on both the audiograms and confirmed with objective testing using otoacoustic emissions. Carbon monoxide poisoning is one of the few recognised causes of reversible sensorineural hearing loss, though it may also lead to a permanent deficit. This is discussed along with other potential causes of reversible sensorineural hearing loss.     

Macrovascular sensorineural hearing loss

Sensorineural hearing loss (SNHL) has many etiologies including vascular sources. Vascular causes of SNHL can occur at the microvascular level. Macrovascular level may be described as arising from vessels proximal to the labyrinthine artery or those vessels that can be visualized without the aid of a microscope. Otologic symptomatology and diagnostic evaluation of the SNHL may reveal a macroscopic vascular source. Representative cases of macrovascular sensorineural hearing loss due to aneurysm, arteriovenous malformation, and vertebrobasilar artery dolichoectasia are presented.     

Treatable sensorineural hearing loss

Sensorineural hearing loss is generally felt to be an untreatable medical condition. However, in some cases, prompt diagnosis and treatment of the underlying condition may reverse the deafness. This article summarizes various treatable forms of sensorineural hearing loss and provides illustrative cases histories of patients who have had sensorineural hearing losses that were improved by medical or surgical intervention. Patients with reversible sensorineural deafness due to inadvertent aminoglycoside over-dosage, congenital cholesteatoma, Meniere's syndrome, blood coagulopathy, and perilymphatic fistula all had improvements in auditory function after medical or surgical intervention. Recent experimental studies on animals may explain the basic mechanisms behind hearing loss and recovery. Aminoglycoside ototoxicity appears to have an initial reversible step, followed by a permanent process. Early endolymphatic hydrops and fistulas may cause mechanical effects in the cochlea which can be corrected. Coagulopathy may cause hypoxia which reverses after anticoagulation. These observations reveal that animal experiments can be useful in explaining human auditory dysfunction of the reversible type.     

Carbamazepine-induced sensorineural hearing loss

Carbamazepine is a commonly prescribed anticonvulsant medication that affects various levels of the nervous system. We report a case of temporary sensorineural hearing loss in a patient after overdosing with 36 g of carbamazepine. Six days after the overdose, the patient complained of bilateral hearing loss and tinnitus. Audiograms revealed a 30- to 40-dB sensorineural hearing loss bilaterally. Another audiogram 2 weeks later showed a complete recovery in both ears accompanied by a clinical resolution in audiovestibular symptoms. Carbamazepine is used to treat partial and generalized seizures, trigeminal neuralgia, and bipolar illness. Adverse effects are not common but most frequently include dizziness, drowziness, nausea, and skin rashes; rare complications are agranulocytosis, bradycardia, and heart block. Documented hearing loss as a side effect of carbamazepine has not been reported, to our knowledge.     

Intratympanic steroids for sensorineural hearing loss

Corticosteroids are standard treatment for a number of inflammatory and immune-mediated inner ear diseases. In recent years there has been growing interest in intratympanic administration of steroids as a means of achieving high inner ear drug concentration and low risk of systemic side effects. Idiopathic sudden sensorineural hearing loss seems to be the condition with the greatest potential for both study and clinical use of intratympanic steroid treatment. Despite promising preliminary observations, there re-main many unanswered questions about this treatment modality.     

Acute low-tone sensorineural hearing loss

Two-hundred forty-one patients with acute low-tone sensorineural hearing loss (ALSH) who consulted my clinic from 1987 to 1996 were retrospectively investigated. The results were as follows: (1) In 110 patients, the sum of hearing level in three low frequencies (125 Hz, 250Hz and 500Hz) was more than 100dB, and that in three high frequencies (2KHz, 4KHz and 8KHz) was less than 60dB. This audiological finding is a widely accepted criterion for the diagnosis of ALSH. One-hundred thirty-one patients did not fit this criterion. (2) The annual number of ALSH patients gradually increased during these ten years due to an increase in the number of female patients. (3) A high incidence of young females characterized these ALSH patients. (4) Of 162 patients, 64.8% and 17.9% showed complete and partial recovery of hearing, respectively. (5) The recovery rates were compared in two groups, one group consisted of patients whose sum of hearing level in the three lower frequencies was more than 100dB, and the other group was comprised of patients whose sum of hearing level in the same lower frequencies was less than 100 dB. There was no statistical difference in recovery rate between the two groups. (6) The frequency distribution of the mean of hearing level in the three lower frequencies was investigated. The mean and standard deviation was 39.1 +/- 11.8dB. By histogram, these results resembled a normal distribution. This suggests that these 241 patients has same disease entity. The pathophysiological condition of ALSH must not be various. Also, that ALSH has the peculiarity that an approximate 40 dB hearing loss may be a normal occurrence.     

鼓室注射地塞米松治疗突发性聋

目的：报告鼓室注射地塞米松治疗突发性感音神经性聋（突聋）的疗效。方法：对1例双耳突聋患者行鼓室注射地塞米松治疗。结果：双耳纯音气导听阈下降40dB以上。结论：鼓室注射地塞米松是治疗突聋的有效方法。     

Idiopathic sudden sensorineural hearing loss

Idiopathic sudden sensorineural hearing loss remains one of the major unsolved otologic emergencies. In this paper the most important recent clinical literature is reviewed, a new method of clinical staging is presented, and unexplored potential treatments are presented. The method of clinical staging presented here is based on four elements represented by the acronym HEAR. The individual elements of the staging are hearing threshold (H), elapsed time from onset (E), audiogram shape (A), and related vestibular symptoms (R). Insufficiently explored potential treatments of sudden hearing loss include antiviral drugs, rheologic agents, and free radical scavengers.     

Experimental autoimmune sensorineural hearing loss

Alterations in host immunity result in a number of disorders affecting multiple organ systems, including the inner ear. The mechanism of injury is poorly understood; as such, this study investigated whether an experimental model of autoimmune sensorineural hearing loss (ASNHL) could be established. Animals were immunized with heterologous inner ear antigen and then evaluated for evidence of evolving inner ear autoimmunity. These animals uniformly developed antibodies to inner ear antigen in their sera and perilymph and 12 of 38 ears showed significant increases in action potential thresholds. Histopathological lesions consisted of loss of cochlear neurons, perivascular plasma cell infiltrates, edema, and extravasation of erythrocytes. These findings are characteristic of autoimmune injury and suggest the establishment of an experimental model of ASNHL in which to further investigate this clinical disorder.     

Noise-induced autoimmune sensorineural hearing loss

Typically, autoimmune sensorineural hearing loss has been described as a slowly progressive, asymmetric hearing loss that is responsive to medications traditionally used in the treatment of other autoimmune conditions. These medications include steroids and cytotoxic drugs. Inciting factors in autoimmune inner ear disease are rarely cited. We describe a case of episodic sudden hearing loss triggered consistently by environmental noise. The hearing loss was responsive to steroids at the time of each occurrence and was determined to be autoimmune. This case raises questions about the relationship between autoimmune inner ear disease and sensitivity to environmental noise that warrant further research.     

Aspirin-induced hearing loss as a model of sensorineural hearing loss

Performance in forward-masking, temporal-integration, and gap-detection tasks was measured in five normal-hearing subjects before and during a five-day period of aspirin use. The drug regimen was 3.9 g per day, taken in four equal doses at 6-h intervals. In the subjects showing substantial temporary hearing loss induced by the aspirin. (1) forward masking declined at about a normal rate as the masker-to-signal interval was increased. (2) the temporal-integration functions were flatter than normal, and (3) detection of a temporal gap was worse than normal at low sound-pressure levels (SPLs) but was essentially normal at levels above about 60 dB SPL. These aspirin-induced changes in performance are similar to the differences observed between normal listeners and listeners with mild sensorineural hearing loss. Thus, temporary, aspirin-induced hearing loss offers promise as a model condition for sensorineural hearing loss. The advantages offered by this model include all those typically attributed to within-subjects experimental designs, as well as the ability to manipulate the amount of hearing loss. Its primary disadvantages are that the hearing loss is not asymmetrically distributed toward the high-frequency region, as it typically is with sensorineural deafness, and there are large individual differences in the amount of temporary hearing loss induced by fixed doses of aspirin.     

Intratympanic methylprednisolone for sudden sensorineural hearing loss.

OBJECTIVE: Corticosteroids are commonly used for the treatment of sudden sensorineural hearing loss (SSHL). In this study, the effectiveness of intratympanic (IT) corticosteroid injection was studied and compared with a control group on patients with SSHL who failed systemic corticosteroid treatment. MATERIALS AND METHODS: A total of 19 patients as a retreatment group (RG) and 18 patients as a control group (CG), all failed high-dose intravenous and oral corticosteroid treatments, were included in this study. These patients were invited back, and IT methylprednisolone was injected five times via 3-day intervals in RG and followed-up for a mean period of 24.9 months (range, 7-30 mo). Audiological evaluations were performed initially, a week after the completion of the injections, monthly in the following first 3 months, and at the end of follow-up period in RG. The CG was followed-up for 3 months after the completion of systemic corticosteroid treatment without any additional drug administration. RESULTS: The mean age was 52.6 years (range, 20-79 yr) in RG and 59.9 years in CG. The mean pure-tone average for speech frequencies (500-4,000 Hz) at baseline audiogram and at the first month, at the third month, and at last controls were 65.2 (range, 43-102 dB), 45.4 (range, 23-77 dB), 43.6 (range, 30-77 dB), and 44.5 (range, 33-77 dB) dB, respectively, in RG. The mean pure-tone averages for speech frequencies (500-4,000 Hz) at the end of systemic treatment and at third-month control were 63.5 (range, 44-98 dB) and 59.0 (range, 40-100 dB) dB, respectively, in CG. The hearing gain that is equal to or more than 10 dB was achieved in 14 patients (73.6%) at the last control in RG. No hearing gain could be detected in the CG. No serious side effect was observed with IT treatment. CONCLUSION: We conclude that IT methylprednisolone injection provides more significant hearing improvement for patients that failed with previous high-dose systemic corticosteroid administration than systemic corticosteroid treatment alone. So it may be the first-step medical treatment of idiopathic SSHL alone or at least may be combined with the systemic corticosteroid administration.