PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Retrocochlear Diseases”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

Intratympanic dexamethasone for sudden sensorineural hearing loss after failure of systemic therapy.

OBJECTIVE: Intratympanic steroids are increasingly used in the treatment of inner ear disorders, especially in patients with sudden sensorineural hearing loss (SNHL) who have failed systemic therapy. We reviewed our experience with intratympanic steroids in the treatment of patients with sudden SNHL to determine overall success, morbidity, and prognostic factors. HYPOTHESIS: Intratympanic steroids have minimal morbidity and the potential to have a positive effect on hearing recovery in patients with sudden SNHL who have failed systemic therapy. STUDY DESIGN: The authors conducted a retrospective review. METHODS: Patients presenting with sudden SNHL defined as a rapid decline in hearing over 3 days or less affecting 3 or more frequencies by 30 dB or greater who underwent intratympanic steroids therapy (24 mg/mL dexamethasone) were reviewed. Excluded were patients with Meniere disease, retrocochlear disease, autoimmune HL, trauma, fluctuating HL, radiation-induced HL, noise-induced HL, or any other identifiable etiology for sudden HL. Patients who showed signs of fluctuation of hearing after injection were excluded. Pretreatment and posttreatment audiometric evaluations including pure-tone average (PTA) and speech reception threshold (SRT) were analyzed. Patient variables as they related to recovery were studied and included patient age, time to onset of therapy, status of the contralateral ear, presence of diabetes, severity of HL, and presence of associated symptoms (tinnitus, vertigo). A 20-dB gain in PTA or a 20% improvement in SDS was considered significant. RESULTS: : Forty patients fit the criteria for inclusion in the study. The mean age of the patients was 54.8 years with a range from 17 to 84 years of age. Overall, 40% (n = 16) showed any improvement in PTA or SDS. Fourteen (35%) men and 26 (65%) women were included. Using the criteria of 20-dB improvement in PTA or 20% improvement in SDS for success, 27.5% (n = 11) showed improvement. The mean number of days from onset of symptoms to intratympanic therapy was 40 days with a range of 7 days to 310 days. A statistically significant difference was noted in those patients who received earlier injection (P = .0008, rank sum test). No patient receiving intratympanic dexamethasone after 36 days recovered hearing using 20-dB PTA decrease or a 20% increase in discrimination as criteria for recovery. Twelve percent (n = 5) of patients in the study had diabetes with 20% recovering after intratympanic dexamethasone (not significantly different from nondiabetics at 28.6%, Fisher exact test, P = 1.0). Comparison to other studies that used differing steroid type, concentration, dosing schedule, inclusion criteria, and criteria for success revealed, in many instances, a similar overall recovery rate. CONCLUSIONS: Difficulty in proving efficacy of a single modality is present in all studies on SNHL secondary to multiple treatment protocols, variable rates of recovery, and a high rate of spontaneous recovery. Forty percent of patients showed some improvement in SDS or PTA after treatment failure. When criteria of 20-dB PTA or 20% is considered to define improvement, the recovery rate was 27.5%. Modest improvement is seen with the current protocol of a single intratympanic steroid injection of 24 mg/mL dexamethasone in patients who failed systemic therapy. Dramatic hearing recovery in treatment failures was rarely encountered. No patient showed significant benefit from intratympanic steroids after 36 days when using this protocol for idiopathic sudden SNHL. If patients injected after 6 weeks are excluded from the study, the improvement rate increases from 26.9% to 39.3%. Earlier intratympanic injection had a significant impact on hearing recovery, although with any therapeutic intervention for sudden SNHL, early success may be attributed to natural history. If we further exclude seven patients treated with intratympanic steroids within 2 weeks of the onset of symptoms (i.e., study only those patients treated with intratympanic dexamethasone between 2 and 6 weeks after onset of symptoms), still, 26% improved by 20 dB or 20% SDS. The recovery rates after initial systemic failure are higher than would be expected in this treatment failure group given our control group (9.1%) and literature review. These findings indicate a positive effect from steroid perfusion in this patient population.

Adolescent↗

Oral steroid treatment of sudden sensorineural hearing loss: a ten year retrospective analysis.

OBJECTIVE: To describe ten years of experience with Sudden Sensorineural Hearing Loss and compare the outcomes with and without treatment with oral corticosteroids. STUDY DESIGN: Retrospective review of medical records. SETTING: Large specialty hospital, Department of Otolaryngology. PATIENTS: Patients presenting with sudden onset (72 hours) unilateral sensorineural hearing loss, with no evidence of Ménière's Disease, acoustic injury, retrocochlear disease, and other specifiable disorders. INTERVENTIONS: The majority of patients received a standard course of oral corticosteroids (Prednisone 60 mg and taper). A smaller group declined treatment. MAIN OUTCOME MEASURES: Recovery of hearing sensitivity was measured using standard audiometry and reported as change in Pure Tone Average. Word recognition scores were also analyzed. RESULTS: When severe-to-profound cases are analyzed, a significant improvement (p <.01) in Pure Tone Average is seen in cases treated with steroids versus those untreated. When milder cases are included, a statistical floor effect prevents differentiation of these groups. Word recognition scores were significantly improved (p <.05) in the treated group. CONCLUSIONS: Application of steroid medication significantly improves the recovery outcomes in cases of Severe Sudden Sensorineural Hearing Loss.

Administration, Oral↗

Is hyperventilation-induced nystagmus more common in retrocochlear vestibular disease than in end-organ vestibular disease?

Hyperventilation-induced nystagmus (HVIN) has previously been shown by the senior author to be common in patients with both acoustic neuromas and following resection. The recurrent study's aim was to examine if HVIN was specific for retrocochlear pathology. To test this, the incidence of HVIN in 24 patients with confirmed acoustic neuroma was compared with its incidence in 38 patients with end-organ vestibular disease (defined as a greater than 25% reduction in caloric testing). Hyperventilation was carried out for 90 seconds. The results showed that 58% of the acoustic neuroma group were positive for HVIN versus 18% of the end-organ group. This difference was very significant on chi-square testing (p < .002). Hyperventilation-induced nystagmus appears to be much more prevalent in retrocochlear pathology than in end-organ pathology.

Adult↗

Special audiometric test battery in 121 proved acoustic tumors.

The usefulness of a special audiometric test battery was analyzed in relation to overall and individual test efficiency for the diagnosis of retrocochlear disease. Data were collected and analyzed from 118 patients with 121 surgically confirmed acoustic neuromas and were compared with an earlier report of 200 similar cases. While audiologic testing plays a major role in the identification of retrocochlear disease, the test battery is not highly efficient. Eleven percent of our neuromas had no audiologic signs and, therefore, escaped audiologic detection. The efficiency of individual tests range from 47% to 77%, while the difference in efficiency between the tone-decay test (77%) and the entire battery (89%) indicates the continued need for more than one test. The low efficiency of some of the components justifies reappraisal and revision of the present test battery.

Audiometry↗

Audiological findings in 125 cases of acoustic neuromas.

The audiological findings in 125 patients with surgically confirmed acoustic neuromas are presented. Following the classification by Pulec et al. (1971) we found 20 medium-size and 105 large tumours; small tumours were not represented. A clear connection between the degree of hearing loss and tumour size was noted, while there was no correlation between duration of history and tumour size. An attempted evaluation of the different audiological tests (ABLB and Metz recruitment test, speech discrimination scores, tone decay, reflex decay, and Békésy tracings) that were applied to the patients, has been made. Attention is called to some audiological findings which, to our knowledge, have not been described previously. No patient in the entire material had normal hearing; 73 had anacusis, and 52 hearing losses of varying degree. In the presence of a normal contralateral ear, the evaluation of audiological tests at PTA thresholds poorer than 80 dB is rather questionable. Attention was therefore concentrated on 32 patients with a hearing loss of 80 dB or less. The pathophysiological basis for the typical hearing loss in patients with retrocochlear disease is a reduction in the number of active fibers in the acoustic nerve and it was to be expected that abnormal findings would be present especially in those tests that exert the greatest demand on the total transmission capacity of the nerve, in other words with the application of intense and/or prolonged sounds. The Metz test is just such a procedure and it is not surprising that it shows the highest degree of validity between all the tests. No single test suffices to distinguish cochlear from retrocochlear disease and it is necessary to use a battery of tests. Any unexpected variability in the outcome of ordinary routine test results has gradually become one main indication to pursue the diagnosis with more elaborate procedures, ant it has been a great help always to apply the Metz test as a part of our routine clinical examination.

Adult↗

An objective method of analyzing cochlear versus noncochlear patterns of distortion-product otoacoustic emissions in patients with acoustic neuromas.

OBJECTIVES: To objectify the effects of retrocochlear disease on distortion-product otoacoustic emissions (DPOAEs) by developing a computer-based software strategy for classifying DPOAE patterns as cochlear or noncochlear and to evaluate the sensitivities of these techniques in a large series of patients with unilateral acoustic neuromas. STUDY DESIGN: Development of a novel, software-based method of DPOAE analysis, which was evaluated with data obtained from a retrospective review of the results from audiometric tests performed in a series of patients. METHODS: A computer-based software strategy was developed, using frequency-specific data from normal-hearing adults, for the purpose of distinguishing cochlear from noncochlear patterns of hearing loss, by determining the discrepancies between DPOAEs and behavioral audiometry. Preoperative pure-tone thresholds and DPOAEs from 97 patients with surgically confirmed acoustic neuroma were compared using an objective method and a standard, subjective technique that was considered to be the gold standard. The effects of bilateral hearing losses, such as noise-induced hearing loss and presbycusis, were accounted for during the analysis to isolate the effects of the tumors on hearing thresholds and DPOAEs. RESULTS: Overall, 55 (57%) of the tumor ears were assigned to the cochlear group (i.e., DPOAEs consistent with hearing thresholds), 40 (41%) to the noncochlear group (i.e., DPOAEs inconsistent with hearing thresholds), and 2 (2%) to an indeterminate group, using the subjective technique for classifying DPOAEs. There was no significant difference in the categorization of the patients with acoustic neuroma when employing the objective strategy. The objective algorithm, when modified to maximize the number of noncochlear identifications, led to assignments of 36 (37%) to the cochlear, 57 (59%) to the noncochlear, and 4 (4%) to the indeterminate categories. CONCLUSIONS: Subjective analysis of a large series patients with acoustic neuromas showed that the majority of ears with tumors demonstrated cochlear (57%), rather than non-cochlear (41%), patterns of DPOAEs. The computerized, software-based algorithm developed for differentiating cochlear from noncochlear patterns of DPOAEs in patients with retrocochlear disease had a maximum sensitivity of 59%. This value was significantly higher than that reported in previous studies.

Adult↗

Mass screening for retrocochlear disorders: low-field-strength (0.2-T) versus high-field-strength (1.5-T) MR imaging.

BACKGROUND AND PURPOSE: In patients with clinical symptoms suggestive of a retrocochlear disorder, contrast-enhanced T1-weighted spin-echo (SE) high-field-strength MR imaging is considered the criterion standard in assessing vestibular schwannoma. However, only 10-20% of its findings are pathologic. Our purpose was to prospectively compare the performance of low-field-strength MR imaging in screening for retrocochlear disorders, with high-field-strength MR imaging as the criterion standard. METHODS: A total of 287 patients with suspected retrocochlear disease underwent axial 1.5-T MR imaging with a T1-weighted SE sequence before and after contrast enhancement and with a high-resolution T2-weighted construction interference in steady state sequence. At immediate follow-up, the same patients underwent axial 0.2-T T1-weighted SE imaging without additional contrast enhancement. Results were classified as negative, positive, or uncertain and were analyzed in light of the patients' clinical symptoms. RESULTS: MR imaging at 1.5 T depicted 63 disorders (21.95%), including 53 schwannomas, three other tumors, and seven other disorders (ie, gadolinium-enhancing inner ear, facial nerve, or meninges). MR imaging at 0.2 T showed evidence of 58 disorders; five disorders were not detected, although all schwannomas and other tumors were seen, including those smaller than 2 mm, and only two (28.6%) of the other disorders were detected. When correlated with clinical data, results showed that the five undetected disorders occurred in patients with unusual clinical signs. CONCLUSION: MR imaging at 0.2 T provided high sensitivity in detecting vestibular schwannoma of the internal auditory canal or cerebellopontine angle; it can be used for mass screening for this disease. Positive and uncertain imaging findings should be followed up with high-field-strength MR imaging.

Cerebellopontine Angle↗

[Acoustic oto-emissions. Clinical uses].

Otoemissions are acoustic signals emitted by the cochlea in response to a short acoustic stimulation (click) that may be recorded with a miniaturized microphone placed within the external auditory canal. They reflect the active mechanisms of the cochlea as they relate to the contractile properties of the outer hair cells, which determine the cochlear properties of sensitivity to and selectivity of frequencies. We have been studying for 5 years the clinical applications of otoemissions in over 500 patients. Otoemissions in 100% of normal ears may be recorded, and the detection threshold is generally 10 dB lower than the psycho-physiological threshold. In pathology, otoemissions present a practical interest in the following applications: objective investigation of perception hearing loss, early screening of cochlear disease consecutive to administration of ototoxic drugs, or sound-induced trauma; exploration of Meniere's disease; study of modifications induced by osmotic substances; diagnosis of retrocochlear disease; quick objective assessment of cochlear function in the newborn and the child.

Acoustic Stimulation↗

The clinical application of acoustic distortion products.

Otoacoustic emissions provide an objective measure of hair-cell function that is independent of retrocochlear activity. Because of their frequency specificity, distortion-product emissions have great potential for clinical use. The present report describes the results of initial studies in patients with known cochlear or retrocochlear disease, diagnosed with standard otologic and audiologic tests. The cochlear group consisted of those diagnosed with noise-induced hearing loss, Meniere's disease, or hereditary hearing loss, whereas patients with acoustic neuroma comprised a retrocochlear group. A final group consisted of patients with sudden sensorineural hearing loss of unknown origin. Detailed distortion-product emission testing included the computer-controlled acquisition of "audiograms" and response/growth functions. The outcomes of these studies demonstrated that distortion-product emissions provide a noninvasive, frequency-specific test of sensory-cell function that objectively depicts the boundary between normal and abnormal hearing. These emissions were also able to effectively track dynamic changes in progressive disease processes. Finally, as a screening tool, acoustic distortion products provide an objective means of assessing cochlear status in infants and young children and in adults at risk for hearing loss. Because acoustic distortion products accurately measure the sensory component of a sensorineural hearing loss, distortion-product testing may play an important role in the diagnosis and treatment of cochlear dysfunction.

Adolescent↗

Cryptococcal meningitis: implications for the otologist.

Cryptococcal meningitis can present to the otologist with hearing loss and vestibular dysfunction. A man with cryptococcal meningitis presenting with bilateral profound sensorineural hearing loss and vestibular dysfunction is described. The difficulty in arriving at the diagnosis and consequences of misdiagnosis are discussed. Histological and clinical studies suggest that the cochlear nerve is likely to be damaged in patients who have deafness associated with this disease. Retrocochlear damage may result in cochlear implantation having a poor outcome.

Acute Disease↗

Usefulness of 1000 Hz tone-burst-evoked responses in the diagnosis of acoustic neuroma.

The auditory brain stem response (ABR) has become widely recognized as a sensitive and cost-effective screening modality in neuro-otologic diagnosis. However, the audiometric characteristics of the test ear may obscure the interpretation of the click-evoked ABR, particularly in the face of high-frequency hearing loss. It is often unclear whether latency delays or absent responses are attributable to retrocochlear disease or simply to the magnitude of the patient's hearing loss. The acoustic click stimulus commonly used in ABR testing activates predominantly the basilar membrane in the 2000 to 4000 Hz range. Because many cochlear and retrocochlear processes are associated mainly with hearing loss in this range, we have found it helpful in selected cases to use 1000 Hz tone-burst stimuli to circumvent the effects of elevated hearing thresholds on the ABR. In this article, our experience with the use of 1000 Hz nonlinearly gated tonebursts in 17 patients with acoustic neuroma is presented.

Adult↗

Masking level differences encountered in clinical populations.

Methods for measuring masking level differences (MLDs) at 500 Hz and for spondees were used with 290 subjects: 50 persons with normal hearing and 240 patients with various diseases. Of particular interest was whether techniques currently in clinical use could be used with ease, dispatch, and profit in determining MLD size. The methods selected, which were variations of Békésy audiometry and speech reception threshold procedures, proved clinically feasible. Results revealed differences in behavior from one group of subjects to another. Although MLDs were not affected by cortical lesions, they were very often abnormally small for patients with eight-nerve tumor, Meniére's disease, or multiple sclerosis. The high incidence of abnormally small MLDs in populations with normal sensitivity to pure tones and speech but with evidence of subcortical central lesions, such as patients with multiple sclerosis, suggests that the MLD tasks can be of diagnostic value in detecting retrocochlear lesions. However, in persons with hearing loss or significant interaural differences in threshold sensitivity, or both, the MLD tests are not always reliable in differentiating cochlear from retrocochlear disease.

Acoustic Stimulation↗

False positive stapedial reflexes and brain stem evoked response findings in patients with suspected retrocochlear lesions.

Patients with suspected retrocochlear disease are usually evaluated with stapedial reflex studies and BSER. Positive responses on these tests usually indicate the need for CT scans with air contrast myelogram. We have been impressed with the lack of sensitivity of these audiometric tests in separating tumor from non-tumorous causes. Although we have never found an acoustic neuroma or cerebellopontine angle tumor without stapedial reflex and BSER abnormalities, we have encountered 20 patients who have strong evidence to support a retrocochlear tumor on audiometric testing but with negative CT with air contrast scans. This report will deal with our experience with these cases and indicate the necessity for obtaining air contrast CT scans before alarming the patient about a retrocochlear disorder or possible surgery. There appear to be many non-tumorous disorders associated with stapedial reflex decay and positive BSER.

Adult↗

Magnetic resonance imaging in acoustic neuroma diagnosis.

Magnetic resonance imaging (MRI) is capable of providing excellent images of the contents of the internal auditory canal and cerebellopontine angle. In order to determine whether MRI is comparable to air contrast computed tomography in the diagnosis of small acoustic neuromas, 44 patients with suspected retrocochlear disease were studied with both CT and MRI. Twenty-one lesions were identified successfully with MRI and CT. The size of the tumors ranged from 4 mm to 5 cm. In twenty-three nontumor patients the normal audiovestibular nerve bundles were well visualized. Air contrast CT, on the other hand, was falsely positive in two cases. The results of this study indicate that MRI is suitable as the primary anatomic investigation in patients suspected of having retrocochlear lesions. It has the advantages of being highly reliable as well as free of ionizing radiation and the need for invasive procedures. The expense of MRI compares favorably with that of combined intravenous and gas contrast CT.

Adult↗

MR imaging of the acoustic nerves and small acoustic neuromas at 0.6 T: prospective study.

To evaluate the capability of magnetic resonance (MR) in imaging normal acoustic nerves, 12 volunteers without signs or symptoms of intracranial disease were examined using a 0.6 T superconductive system. Several spin-echo (SE) pulse sequences were tested to identify the optimal sequence for demonstration of the acoustic nerve bundle. Repetition times (TRs) varied from 300 to 2000 msec and echo times (TEs) from 30 to 120 msec. A single-slice technique was used with 5 and 8 mm sections, one or two data acquisitions per projection, and axial and coronal imaging. The normal acoustic nerves were demonstrated readily by MR in axial and/or coronal sections. The distal parts of the nerves and tumors were imaged best with SE 1500/60. The medial extremities of the seventh and eighth nerves tended to be obscured in this sequence by brightening the cerebrospinal fluid signal adjacent to the brainstem, but they were demonstrated clearly with 500 or 800 msec TR and 30 msec TE. Five patients were studied who had hearing loss and evidence of retrocochlear disease. In four patients, MR imaging demonstrated five acoustic nerve tumors ranging in size from purely intracanalicular to a 12 mm cisternal component. In the fifth case, no tumor was identified by MR imaging or gas computed tomographic (CT) cisternography. Contrast-enhanced CT using a Siemens Somatom DR 3 or GE CT/T 8800 scanner failed to provide convincing evidence of tumor in any case, while gas CT cisternography was positive in all five tumors. All five acoustic neuromas were identified readily using the SE sequences that proved optimal for demonstration of normal nerves. This experience revealed that MR imaging can demonstrate the eighth nerve complex well and reliably. Single-slice (5 or 8 mm) technique is adequate, but multislice without tissue gaps (used recently) is more efficient. Small, even intracanalicular, acoustic neuromas are imaged effectively, indicating that the method is capable of superseding contrast CT cisternography, particularly with improving technology.

Atrophy↗

[Objective auditory brainstem response threshold deficits in patients with cerebellopontine angle tumors].

The established criteria of auditory brainstem responses (ABR) such as JV latency, JI-V interpeak latency and interaural differences of latency or amplitude have been found to be sensitive for detecting tumors of the cerebellopontine angle if a response is present. However, the ABR can be absent in cases of acoustic neuromas because of desynchronization, even though pure-one audiometry indicates that responses should be present. This retrospective study compared the ABR and pure-tone thresholds in 234 cases with cerebellopontine angle tumors and a control group of 181 cases with sensory hearing losses in order to quantify threshold discrepancies. The average deficit of the objective ABR threshold (DOABRT) to the subjective pure-tone threshold for those frequencies between 1-6 kHz was 3.6 dB for the control group (ABR and pure tone thresholds very close) and 31.2 dB for the tumor group (ABR threshold much higher than the pure-tone threshold). ABR thresholds 30 dB higher than the high-frequency pure tone thresholds were found in 40.6% of the tumor group and in none of the control group. Thus, deficits of the ABR threshold >30 dB can be considered to be an additional criterion for detecting retrocochlear disease and increases ABR sensitivity for tumor detection even if responses are absent.

Adolescent↗