15-year follow-up for steroid-responsive, fluctuating hearing loss in the ear with endolymphatic hydrops confirmed by magnetic resonance imaging

Autoimmune mechanisms may play crucial roles in the etiology of endolymphatic hydrops (ELH), which was previously regarded as a postmortem finding in the temporal bone. Recently, ELH has been visualized using 3-T MR imaging in living patients. A 47-year-old woman with deafness in the left ear since adolescence developed right-sided steroid-responsive sensorineural hearing loss in the low frequencies. During over 15 years of follow-up at our otolaryngology clinic, acute deteriorations of hearing in the only hearing ear repeatedly recovered with administration of intravenous and oral steroids. Hearing in the only hearing ear at 62 years old was preserved and comparable to that at 47 years old. At 61 years old, cochlear ELH was documented bilaterally on MR imaging, appearing more severe in the deafened ear than in the hearing ear. This case provides new evidence of the potential steroid-responsiveness of hearing loss due to contralateral-type delayed ELH distinctly visualized on MR imaging.

Live Imaging of the Dehydration Effect of Isosorbide on the Normal and Hydropic Guinea Pig Cochleae Using Optical Coherence Tomography

OBJECTIVE

To investigate the isosorbide-induced dehydration effect on the endolymphatic space by intratympanic administration of isosorbide.

BACKGROUND

Isosorbide, an osmotic diuretic, is used orally as a typical conservative therapy for Menière's disease (MD) in Japan. The dehydration effect occurs 6 hours after isosorbide ingestion. Intratympanic administration of isosorbide resolves endolymphatic hydrops faster than oral ingestion. In addition, the dehydration effect has never been shown directly. Therefore, we investigated the dehydration effect of intratympanic administration of isosorbide on endolymphatic hydrops using optical coherence tomography.

METHODS

We used eight Hartley guinea pigs, divided into normal and hydrops groups. In the hydrops group, the animals underwent endolymphatic sac obliteration to create endolymphatic hydrops. We obtained midmodiolar section images of the cochleae using optical coherence tomography. Then, 50 to 70% isosorbide was sequentially administered intratympanically for 5 minutes, and the apical turn of the cochlea was observed. The relative midmodiolar cross-sectional area of the scala media was calculated for quantitative assessment of the endolymphatic space.

RESULTS

In the normal group, 50% isosorbide had a slight but significant dehydration effect on the scala media; at 55 to 70%, Reissner's membrane became flat. In the hydrops group, 50% isosorbide slightly reduced endolymphatic hydrops; 65% flattened Reissner's membrane, and 70% slightly concaved it toward the basilar membrane.

CONCLUSION

The results suggest that we could select the concentration of isosorbide according to the stage or severity of MD and relief from acute attack. Intratympanic administration of isosorbide may be a promising treatment for patients with MD.

Gentamicin delivery to the inner ear: Does endolymphatic hydrops matter?

Introduction

Middle ear application of gentamicin is a common medical treatment for uncontrolled Ménière’s disease. The objective of the study was to evaluate the impact of endolymphatic hydrops on inner ear delivery.

Methods

Perilymph gentamicin concentrations and correlation with endolymphatic hydrops in an animal model were assessed. A group of 24 guinea pigs was submitted to surgical obstruction of the endolymphatic sac and duct of the right ear. Gentamicin was applied either to the right ear’s round window niche or through a transtympanic injection. Perilymph specimens were collected at different times. Histologic morphometry was used to evaluate both turn-specific and overall hydrops degree.

Results

In animals with endolymphatic hydrops, lower concentrations of gentamicin were observed after 20 or 120 minutes of exposure and in both types of administration, when compared to controls. This difference reached statistical significance in the round window niche application group (Mann-Whitney, p = 0,007). A negative correlation between perilymphatic gentamicin concentration and hydrops degree could be observed in both groups, after 120 minutes of exposure (Spearman correlation, round window niche p<0,001; TT p = 0,005).

Conclusions

The study indicates that the endolymphatic hydrops degree has a negative interference on the delivery of gentamicin into the inner ear following middle ear application.

Intratympanic Injections of Dexamethasone in Delayed Endolymphatic Hydrops: A Prospective Clinical Study

OBJECTIVE

This study was designed to evaluate the effectiveness of intratympanic dexamethazone (ITD) for the treatment of ipsilateral delayed endolymphatic hydrops (DEH).

METHODS

Forty-one patients were diagnosed with ipsilateral DEH. Only 37 patients completed this study. Patients were randomly divided into 2 groups. Group A (n = 16) received oral medication, and group B (n = 21) received ITD once weekly for 4 consecutive weeks.

RESULTS

In group A, 6 patients showed improvement in their vertigo. Four patients (25%) showed complete vertigo control, and 2 patients (12.5%) showed substantial vertigo control. In group B, 21 patients showed improvement in their vertigo, 11 patients (52%) showed complete vertigo control, and 10 patients (47%) showed substantial vertigo control. Only 1 case did not show any improvement in their vertigo.

CONCLUSION

ITD is proven to be a valuable and promising alternative modality for the management of ipsilateral DEH.

Intratympanic steroids injection is effective for the treatment of drop attacks with Ménière's disease and delayed endolymphatic hydrops: A retrospective study

Drop attack (DA) associated with Ménière's disease (MD) and delayed endolymphatic hydrops (DEH) is not common and may cause life-threatening clinical problems. The intratympanic dexamethasone (ITD) is one of primary treatments for MD or DEH. Our study investigated the effect of ITD on the DA associated with endolymphatic hydrops (EH).We retrospectively reviewed 10 patients with MD- and DEH-associated DA between January 2009 and December 2013 in Outpatient Department of Otolaryngology, Union Hospital, Wuhan, China. Among them, 7 patients (5 cases with MD, 2 cases of DEH) received ITD (4 times, on weekly basis). Further repeated ITD courses or intratympanic gentamicin (ITG) were given if the vertigo was not satisfactorily controlled. The number of DA and status of vertigo control after intratympanic injection were evaluated. After a follow-up study lasting from 19 to 35 months, DA in 5 cases (71.4%) disappeared after initial ITD course. In 2 cases, DA was altogether controlled after an additional intratympanic injection (repeated ITD or/and ITG).This study showed that ITD promises to be a first-line conservative treatment for MD- or DEH-related DA since the steroid possesses no inner-ear toxicity. Furthermore, for MD- or DEH-related DA refractory to ITD, ITG can be an effective alternative.

Intratympanic injection in delayed endolymphatic hydrops

CONCLUSIONS

The present study showed that intratympanic dexamethasone injection (ITD) is a promising approach for the treatment of contralateral and ipsilateral delayed endolymphatic hydrops (DEH). Moreover, intratympanic gentamicin injection (ITG), as a chemical labyrinthectomy, is a simple alternative for controlling vertigo in patients with ipsilateral DEH.

OBJECTIVE

This study examined the effect of ITD or ITG on DEH.

METHODS

Fourteen patients with DEH completed the clinical and audio-vestibular evaluation. Among them, 10 cases (ipsilateral type: nine cases, contralateral type: one case) were treated with intratympanic injection. Four patients with ipsilateral DEH underwent ITG, five patients with ipsilateral type and one patient with contralateral type received ITD. All 10 cases were followed up for 8-48 months.

RESULTS

Complete and substantial vertigo control was achieved in four of nine ipsilateral DEH patients treated with ITG. In the other five ipsilateral cases who received ITD, two accomplished complete vertigo control and two had substantial control. In one case, the vertigo was not effectively controlled. One case of contralateral DEH underwent ITD and this case had complete vertigo control. The vertigo intensity, vertigo frequency, vertigo duration and the functional level scale after intratympanic injection was decreased significantly.

[Effects of intratympanic injection of dexamethasone on endolymphatic hydrops and changes in guinea pigs inner ear CFTR expression]

OBJECTIVE

To observe the effect of tympanic injection of dexamethasone in the guinea pig endolymphatic hydrops and the change CFTR expression, to explore the effect of glucocorticoid treatment endolymphatic and its possible mechanism.

METHOD

Thirty guinea pigs were divided into three groups: hormone group, water group, control group. The animals(hormone group, water group) in study were injected DDAVP 4 μg/kg in the first 7 d, and will increase to 6 μg/kg in the second 3 d. The control group was given normal saline, continuous 10 d. After twelfth days, the hormone group transtympanic injection of dexamethasone (5 mg/ml, 0.5 ml), and water group, control group transtympanic given normal saline (0.5 ml), continuous injection 5 d. Using immuno- histochemistry and Western blot to detect the cystic fibrosis transmembrane conductance regulator cochlear factor (CFTR) expression.

RESULT

The water group ABR thresholds was significantly higher than that before the experiment (P < 0.01), and the water group was significantly higher than the rest of the groups (P < 0.01); Hormone group compared with the control group increased threshold value (P < 0.05). The control group had no endolym- phatic hydrops, the water group showed varying degrees of endolymphatic hydrops, cochlear duct and vestibular plus cochlear duct area ratio compared with the control group, hormone group was significantly higher (P < 0.01). hormone group area ratio was higher than the control group (P < 0.05). CFTR was primarily expressed in the stria vascularis, Corti's, spiral ligament, basilar membrane, cochlear ganglion,etc . The expression of CFTR in the water group was increased than that in the control group, and the hormone group (P < 0.01); the expression of hormone group increased compared with the control group (P < 0.05).

CONCLUSION

Tympanic injection of dexa- methasone can alleviate the desmopressin acetatein guinea pigs caused by membranous labyrinth, and the improve- ment of the hearing; Tympanic injection of dexamethasone can make the endolymphatic hydrops cochlea of guinea pigs decreased CFTR expression, indicating that the expression and possible mechanisms of CFTR intratympanic steroids reduce endolymphatic hydrops changes.

Furosemide-loading vestibular evoked myogenic potential testing can suggest developing bilateral involvement of unilateral Meniere's disease

CONCLUSIONS

Patients with positive results of furosemide-loading vestibular evoked myogenic potential (F-VEMP) testing in the unaffected ears of unilateral Meniere's disease have a high incidence of developing bilateral lesions.

OBJECTIVE

To clarify the meaning of positive results of F-VEMP testing of the unaffected ear of patients with unilateral Meniere's disease.

METHODS

Twenty-five patients with unilateral Meniere's disease were investigated in this study. The positive group consisted of 6 patients with positive results of F-VEMP testing in the contralateral ear and the negative group consisted of 19 patients with negative results. The incidence of contralateral involvement was compared in both groups by the Kaplan-Meier method.

RESULTS

Contralateral involvement was seen in three cases (50%) in the positive group after 2, 12, and 26 months and in three cases (16%) in the negative group after 27, 56, and 78 months. The positive group had a higher incidence of contralateral involvement than the negative group (p = 0.0017, according to a log-rank test).

Hearing preservation in Guinea pigs with long-standing endolymphatic hydrops

HYPOTHESIS

Interruption of the excitotoxic and inflammatory pathways implicated in endolymphatic hydrops (ELH)-associated hearing loss (HL) should afford hearing protection at the neuronal level.

BACKGROUND

Previous work in our laboratory in the mouse model of ELH shows that dimethyl sulfoxide (DMSO), an anti-inflammatory solvent, can slow the progression of HL before neuronal degeneration occurs. Riluzole, a glutamate release inhibitor, may provide synergistic benefit. This study was designed to quantify the effects of DMSO and riluzole in a long-term model.

METHODS

Guinea pigs with surgically induced ELH were sorted into 3 groups: riluzole+DMSO (Group 1), DMSO alone (Group 2), and untreated controls (Group 3). Animals in Groups 1 and 2 received daily injections of the study drug(s). All animals underwent auditory-evoked brainstem response evaluation every 4 weeks until 24 weeks, when they were sacrificed. Cochleae were preserved; spiral ganglion density was quantified. Animals without hydrops were excluded from the study as surgical failures.

RESULTS

Animals from all groups developed unilateral HL. At the end of the experiment, HL was significantly lower in Group 1 relative to Group 3 (p = 0.049) and trended toward lower in Group 2 relative to Group 3 (p = 0.097). Groups 1 and 2 were not different (p = 0.311). At the cellular level, there is no evidence of neuronal degeneration in either treated group, whereas there is a significant neuronal degeneration in the untreated group.

CONCLUSION

These results confirm the hearing protection observed with DMSO in short-term studies. However, unlike the previous study, which showed no additive benefit to riluzole, the combined treatment group in this study showed a hearing-protective effect at 24 weeks. This indicates a potential additive benefit conferred by riluzole toward long-term hearing protection. The study also finds evidence of statistically significant neuronal protection with both treatment groups. Overall, study provides additional evidence that DMSO and riluzole may preserve or slow the long-term progression of ELH-associated HL.

Endolymphatic hydrops and therapeutic effects are visualized in 'atypical' Meniere's disease

A 53-year-old male with fluctuating low frequency sensorineural hearing loss and tinnitus, but without vertigo, was evaluated by MRI obtained by intratympanic injection of a gadolinium-based contrast agent (GBCA) before and after the administration of isosorbide. The endolymphatic hydrops was semi-quantitatively evaluated by a 3.0-T MR scanner. For quantification, the affected side/contralateral side ratios were calculated. A gadodiamide (a kind of GBCA)-enhanced space surrounding the endolymph in the affected side with a 0.50 ratio (which may have represented endolymphatic hydrops) improved after isosorbide therapy to a 0.98 ratio. Thus, endolymphatic hydrops was demonstrated in a patient with 'atypical' Meniere's disease (MD), suggesting that at least some atypical MD may share similar etiology with, and therefore be a continuum of, MD. Also, therapeutic effects could be visualized by using MRI. Therefore, MRI-based diagnosis of MD-related disease will be a powerful tool not only because of its precision but also its usefulness for therapeutic evaluation.

Dexamethasone inner ear perfusion for subclinical endolymphatic hydrops

We suggest that the term subclinical cochlear hydrops be used to describe patients presenting with aural fullness, stuffiness, or ear pressure when all other diagnoses have been excluded. We reviewed the charts of 20 patients who had presented with a chief complaint of aural fullness, stuffiness, or pressure and who underwent perfusion of the inner ear for 1 month with dexamethasone 4 or 10 mg/ml. The symptoms improved in 13 (68.4%) of 19 patients after treatment. None of these patients reported a worsening of symptoms, and no patient had worse hearing after perfusion. Complications were infrequent, and patients tolerated the treatment well. Perfusion of the inner ear appears to be a safe procedure with little risk.

Effects of a Nitric Oxide Synthase Type II Inhibitor on Compound Action Potential Thresholds in Experimental Endolymphatic Hydrops

HYPOTHESIS

Nitric oxide (NO) is likely to be synthesized by nitric oxide synthase Type II (NOS II) action and may partake in the origin of changes of compound action potential (CAP) threshold observed in guinea pigs with induced endolymphatic hydrops. This study aimed to assess the action of a NOS II inhibitor on CAP thresholds in these experimental samples.

BACKGROUND

In guinea pigs with experimental endolymphatic hydrops, there are lesions on the cochlea and progressive increase of CAP threshold. NOS II was found in the cochlea of this animal model, and it was inferred that NO can contribute by such alterations.

METHODS

The animals were divided into two groups, in which eight received an intake of a NOS II inhibitor, aminoguanidine, and another eight served as a control group. During 16 weeks, CAP thresholds at 1,000, 2,000, 4,000 and 6,000 on electrocochleography were compared between the groups.

RESULTS

The group that had an intake of aminoguanidine showed a lower increase on CAP thresholds at 2,000 (p < 0.05) and 6,000 Hz (p < 0.05) at the 12th postoperative week, and at 1,000 (p < 0.05), 2,000 (p < 0.001), 4,000 (p < 0.001), > and 6,000 Hz (p < 0.001) at the 16th week.

CONCLUSION

We conclude that NOS II inhibitor reduced the elevation of CAP thresholds in experimentally induced endolymphatic hydrops.

Our experience with the medical treatment of endolymphatic hydrops

Ménière's syndrome is an idiopathic disorder of the cochlea and labyrinth. It is caused by endolymphatic hydrops and is a relatively frequent, lifelong disorder affecting patients' quality of life and work performance. This article presents our clinical experience with the medical treatment of this disease. Patients were treated with a blend of drugs according to their condition (stage of illness and presence of associated diseases).

A comparison of dehydration effects of V2-antagonist (OPC-31260) on the inner ear between systemic and round window applications

V2-antagonist (OPC-31260 (OPC)) application to the scala tympani reduced endolymphatic hydrops. In the present study, we investigated whether systemic administration or local infusion via the round window (RW application) of OPC would be more suitable for clinical use. In Experiment 1, the increase ratios of the cross-sectional area of the scala media of experimentally induced endolymphatic hydrops were quantitatively assessed among four groups of non-OPC application, RW application of xanthan gum, systemic application of OPC and RW application of OPC. In Experiment 2, the effects of systemic and RW applications of OPC on plasma vasopressin (p-VP) concentrations and plasma osmolality (p-OSM) were investigated. In Experiment 3, endocochlear DC potential (EP) was measured in guinea pigs with the RW application of OPC. Electron microscopic observations of the stria vascularis and the hair cells were also made. Both systemic and RW applications of OPC significantly reduced endolymphatic hydrops. However, systemic application resulted in the distension of the Reissner's membrane in the non-operated ear, which seemed to be caused by elevated p-VP levels resulting from the systemic application of OPC. In contrast, RW application of OPC produced no apparent toxic effects in the inner ear, as indicated electrophysiological or morphological changes. Thus, drug delivery via the round window is more useful for the clinical application of OPC for medical decompression.

Prognostic relevance of anamnestic and diagnostic parameters in low-frequency hearing impairment

Low-frequency hearing impairment (LFHI) is mainly attributed to endolymphatic hydrops and has a great variety of possible outcomes. At present, no conservative therapeutic regimen has proven to be ‘gold-standard’, and information about the prognostic indicators of LFHI is scarce.

In a retrospective investigation, we evaluated the records of 90 patients who had been treated with infusions improving blood perfusion. In patients lacking complete remission, dehydration infusion therapy was added. We also undertook audiometric follow up. We calculated the outcomes after infusion therapy, dehydration therapy and after long-time hearing follow up, and we determined the prognostic relevance of several parameters of anamnesis and clinical examination to outcomes, for both therapeutic interventions and long-time hearing.

The prognosis of LFHI was significantly correlated to certain anamnestic and clinical parameters; a short duration of the disease, lack of vertigo and female gender implied a better outcome. The pretherapeutic hearing threshold was an important prognostic factor; the outcome was significantly worse in patients with distinct hearing impairment in low or high frequencies, compared with that in patients with little hearing loss. Whereas vertigo was a negative prognostic factor, the results of quantitative vestibular testing were irrelevant to the outcome. The glycerol test failed to predict the effectiveness of dehydration therapy and lacked any value in predicting prognosis.

These results allow the clinician to focus the anamnesis and diagnostic examination on prognostically relevant parameters, thus enabling a better estimation of the long-term disease course and improved counselling of patients. Furthermore, these results help to distinguish valuable from irrelevant diagnostic procedures.

Endolymphatic hydrops as a cause of audio-vestibular manifestations in relapsing polychondritis

Relapsing polychondritis (RP) is characterized by inflammation and subsequent degeneration of cartilage. We report a 61-year-old woman who had RP with audio-vestibular manifestations. She was also diagnosed as having a myelofibrosis with myeloid metaplasia (MMM). Bilateral endolymphatic hydrops (EH) was confirmed by dominant -SP/AP of the electrocochleogram (ECochG). When thalidomide and prednisolone were prescribed for the treatment of MMM, symptoms of RP -- including the inner ear dysfunction -- were ameliorated. Isosorbide, one of the osmotic diuretics commonly used for the treatment of Meniere's disease (MD) in Japan, was also effective in keeping her free from inner ear dysfunction. This is the first report to confirm the existence of EH in a patient with RP with audio-vestibular manifestations. We suppose that an immunological imbalance due to MMM, in conjunction with a specific immunogenetic background, may have played a role in the pathogenesis of RP and the formation of EH in this patient.

Hypothesis: could Meniere's disease be a channelopathy?

Meniere's disease is a clinical syndrome of uncertain aetiology but it is a widespread belief that it is related to endolymphatic hydrops. Clinically, it is a paroxysmal disorder with vertigo and subsequent deafness. It is responsive to acetazolamide and sensitive to the sodium content in the diet, many of the features of the channelopathies. The present paper explores the possibility that it may be related to a channelopathy.

Frequency Dynamics Shift of Vestibular Evoked Myogenic Potentials in Patients with Endolymphatic Hydrops

OBJECTIVE

To measure the frequency dynamics of the vestibular evoked myogenic potential in patients with endolymphatic hydrops.

STUDY DESIGN

A prospective study.

SETTING

A university hospital.

SUBJECTS

The endolymphatic hydrops group consisted of 28 affected ears of patients with definite unilateral Ménière's disease and a control group of 36 ears of 20 healthy volunteers.

INTERVENTIONS

Vestibular evoked myogenic potentials generated by tone bursts at 250, 500, 700, 1,000, 1,500, 2,000, and 4,000 Hz were measured in both groups. Vestibular evoked myogenic potentials were also measured after furosemide administration in six patients in the endolymphatic hydrops group.

MAIN OUTCOME MEASURE

The frequency sensitivity of vestibular evoked myogenic potential, as evaluated by p13-n23 normalized amplitude.

RESULTS

Peak amplitudes were noted at 500 Hz in the control group and at 1,000 Hz in the endolymphatic hydrops group. After furosemide loading, peak amplitude shifted to a lower frequency in four of six ears.

CONCLUSION

The peak amplitude of vestibular evoked myogenic potentials in the endolymphatic hydrops group was at a higher frequency than in the control group. The frequency of the saccule (nu) should be proportional to radical(tau/sigma), where tau is the tension of membrane and sigma is its density. We advocate the hypothesis that the shift in frequency dynamics of vestibular evoked myogenic potential in patients with endolymphatic hydrops originates from the morphologic features of the saccule, analogous to an expanded balloon.

Time Course of Dehydrating Effects of Isosorbide on Experimentally Induced Endolymphatic Hydrops in Guinea Pigs

Osmotic diuretics are therapeutic agents used to reduce endolymphatic hydrops. However, glycerol-induced change in endolymph volume is followed by a rebound phenomenon. In this study, we investigated the rebound phenomenon occurring with isosorbide, an osmotic diuretic used as a therapeutic agent for Ménière's disease in Japan. Forty guinea pigs underwent surgical obliteration of the endolymphatic sac. Thirty received isosorbide orally 1 month after surgery. These animals were sacrificed 3, 6, or 12 h after isosorbide intake. The remaining 10 animals served as controls. Quantitative assessment of changes in the endolymphatic space was performed light-microscopically. Isosorbide reduced cochlear endolymph volume, with a peak reduction 6 h after intake. Thereafter, no prominent rebound phenomenon was noted. Clinically, since isosorbide is orally administered every 8 h, rebound phenomenon need not be considered in the treatment with isosorbide.

The effects of V2 antagonist (OPC-31260) on endolymphatic hydrops

In the present study, two experiments were performed to investigate the influence of OPC-31260 on experimentally induced endolymphatic hydrops in guinea pigs and the regulation of aquaporin-2 (AQP2) mRNA expression in the rat inner ear. In morphological studies, the increases in the ratios of the length of Reissner's membrane (IR-L) and the cross-sectional area of the scala media (IR-S) were quantitatively assessed among normal guinea pigs (normal ears) and three groups with hydropic ears: hydropic ears with no infusion (non-infusion hydropic ears), hydropic ears with an infusion of physiological saline into the scala tympani (saline-infused hydropic ears) and hydropic ears with infusion of 0.3% OPC-31260 into the scala tympani (OPC-infused hydropic ears). IR-Ls in the experimental groups were markedly larger than in the normal ear group, but there was no significant difference among the groups of non-infusion hydropic ears, saline-infused hydropic ears and OPC-infused hydropic ears. The IR-Ss of non-infusion hydropic ears and saline-infused hydropic ears (48.8-49.3%) were statistically different from that of normal ears (6.5%) (Dunnet multiple comparison test, P<0.01). However, IR-S of the OPC-infused hydropic ears (-14.8%) was significantly smaller than those of non-infusion hydropic ears and saline-infused hydropic ears (one-way ANOVA, P<0.01). In the quantitative polymerase chain reaction study, a comparison of the ratio of AQP2 and beta-actin mRNA (MAQP2/Mbeta-actin) was made between water-injected and OPC-31260-injected rats. An intravenous injection of OPC-31260 resulted in a significant decrease in MAQP2/Mbeta-actin both in the cochlea and in the endolymphatic sac (t-test, P<0.001). These results indicate that water homeostasis in the inner ear is regulated via the vasopressin-AQP2 system, and that the vasopressin type-2 antagonist OPC-31260 is a promising drug in the treatment of Meniere's disease.

Ménière's disease and delayed endolymphatic hydrops in children

In order to study the characteristics of pediatric patients (< or = 15 years at onset) with endolymphatic hydrops disorders, we selected 5 patients with Ménière's disease (MD) and 3 patients with delayed endolymphatic hydrops (DEH) from 7418 patients who had visited the Neurotological Clinic of the Toyama Medical and Pharmaceutical University Hospital between 1979 and 1999. Clinical features were characterized as follows: (i) pediatric MD patients were rare, comprising approximately 1.5% of all the 337 MD patients in the sample; (ii) a fluctuating hearing loss, strong positive response in glycerol test, high SP/AP amplitude ratio in electrocochleography and moderate positive response in furosemide vestibulo-ocular reflex test were recorded; (iii) in 2 of the 5 pediatric MD patients, vertiginous attacks had persisted for a long period and they had undergone surgical procedures (sac operation and vestibular neurectomy); and (iv) the ipsilateral type of DEH was observed in 2/3 children, and contralateral DEH in 1/3.

Allopurinol attenuates endolymphatic hydrops in the guinea pig cochlea

Based on the hypothesis that Ca(2+) overload in the scala media may produce endolymphatic hydrops and generate free oxygen radicals (FOR), allopurinol, a xanthine oxidase inhibitor and free radical scavenger, was administered to guinea pigs after the surgical obliteration of the endolymphatic duct. Allopurinol was given intraperitoneally (50 mg/kg/day) for 15 days starting 1 day prior to the surgical blockage procedure. Measurements from histological serial sections of these temporal bones showed that the total volume of the scala media was significantly reduced (p = 0.007) compared with control hydropic ears. There was an indication of reduced incidence of atrophy in sensorineural structures and stria vascularis. These findings suggest that allopurinol may attenuate the development of endolymphatic hydrops and cell damage by preventing the formation of FOR or scavenging FOR. This study may lead to a new aspect of treatment for Menière's disease.

[Evaluation of the effect of streptomycin perfusion of the labyrinth in the treatment of Meniere's disease and endolymphatic hydrops]

OBJECTIVE

To investigate the clinical effect of streptomycin perfusion of the labyrinth (SPL) in the treatment of Meniere's disease.

METHOD

13 patients with Meniere's disease and 3 patients with delayed endolymphatic hydrops (DEH) underwent SPL. The follow-up time was between 5 and 7 years (average 6.3 years).

RESULT

Vertigo was completely controlled in 9 patients, substantialy controlled in 4, limitedly controlled in 2 and not controlled in 1. Hearing was improved in 1 patients, stabilized in 5 and worse in 10. Tinnitus was improved in 3 patients, stabilized in 5 and worse in 8.

CONCLUSION

SPL is a safe and effective method in the treatment of Meniere's disease and DEH, but the hearing may be insulted and tinnitus may be worse in some patients.

Hearing results of intratympanic steroid treatment of endolymphatic hydrops

OBJECTIVES/HYPOTHESIS

This study evaluated the effectiveness of a single application of steroids to the open middle ear in improving short-term hearing in patients with Meniere's disease and cochlear hydrops.

STUDY DESIGN

Retrospective study in which each patient's pretreatment hearing served as the control compared with posttreatment hearing.

METHODS

Patients were treated with a single application of dexamethasone, 8 mg, in hyaluronan. Following tympanotomy and lysis of round window adhesions, steroids were placed in the round window niche with absorbable gelatin sponge and the remainder of the middle ear was then filled with the steroid solution. Systemic steroids were not administered. Audiograms were performed within 1 month before surgery and at least 1 month after surgery.

RESULTS

Between September 1996 and July 1997, 21 ears in 19 patients underwent intratympanic steroid treatment. The criterion for hearing change was a 10-dB or greater change in pure-tone average (PTA), or a 15% change in speech discrimination score (SDS). Of the 15 ears meeting inclusion criteria for this study, five (33%) demonstrated hearing improvement and three (20%) demonstrated hearing deterioration. Maximum improvement was a 38-dB improvement in PTA and a 32% improvement in SDS.

CONCLUSION

A single application of intratympanic dexamethasone/hyaluronan solution directly to the round window did not produce dramatic short-term hearing improvement in patients with endolymphatic hydrops. Although the theoretical basis for intratympanic steroid treatment of endolymphatic hydrops is appealing, we urge close evaluation of the results of specific protocols of intratympanic steroid administration before widespread utilization of this treatment. The choice of steroid, route of administration, frequency of application, and need for simultaneous systemic administration require standardization to adequately assess the efficacy of this treatment.

The possible effect of pregnancy on Ménière's disease

There are few reports on the course of Ménière's disease during pregnancy. We report here the clinical course of Ménière's disease before, during and after pregnancy and discuss the possible effect of pregnancy on Ménière's disease and the treatment of Ménière's disease during pregnancy. In the present case, the vertigo attacks increased up to 10 times per month during early pregnancy, when the serum osmolality was significantly below normal at 268 mosm/kg. As the pregnancy proceeded, the serum osmolality normalized and the vertigo attacks decreased in frequency. The vertigo attacks were treated by oral isosorbide and intramuscular injection of low-dose diazepam. The coincidence of the decline in osmolality with the increase in vertigo attacks points to serum osmolality as a possible factor in the effect of pregnancy on Ménière's disease.

Treatment of ipsilateral delayed endolymphatic hydrops

Nine patients with ipsilateral delayed endolymphatic hydrops were treated. All cases were initially treated by conservative therapy using isosorbide or other drugs and 4 patients have been doing well without surgical intervention, though they occasionally have slight dizziness. Five patients required surgery to control vertigo. Three patients first underwent cochleosacculotomy to maintain the vestibular function in the diseased ear, but vertigo recurred after 6 months in all 3 cases. These 3 patients and another patient who wanted definitive treatment right from the start underwent transmastoid labyrinthectomy which resulted in complete control of vertigo. One patient received chorda tympani nerve section because he did not want his vestibule destroyed. After the nerve section, he has had no vertigo though sometimes dizziness. Transmastoid labyrinthectomy seems to be the best treatment for ipsilateral delayed endolymphatic hydrops.

Effect of isosorbide on distortion-product otoacoustic emissions and endocochlear DC potential in experimentally induced hydropic ears

The effects of isosorbide on distortion-product otoacoustic emissions (DPOAEs) and endocochlear DC potential (EP) were examined in experimentally induced endolymphatic hydropic ears and untreated control ears using 20 albino guinea pigs. DPOAEs and EP in the hydropic ears decreased after obliteration of the endolymphatic duct and sac. The administration of isosorbide restored DPOAEs to the normal level, whereas EP was further reduced. In control ears there was no significant change in DPOAEs and EP after the administration of isosorbide. The results obtained in the present study indicate that the effect of isosorbide on DPOAEs is different from that on EP, and the recovery of DPOAEs in hydropic ears is not a secondary phenomenon due to the recovery of EP.

Intratympanic gentamicin treatment: preliminary results in two patients with Menière's disease

Menière's disease is a vestibular disturbance characterized by episodic vertigo, tinnitus, and fluctuant hearing loss. The long-term effectiveness of available medical and nonablative surgical treatments has been variable, with frequent symptom recurrence. Vestibular neurectomy and labyrinthectomy, surgically ablative techniques, provide more permanent relief from vertiginous attacks. However, these procedures pose possible morbidity and cochlear risk. In this paper, preliminary results are presented for two patients who underwent intratympanic gentamicin application. Like surgical labyrinthectomy, intratympanic use of gentamicin is intended as an ablative procedure, but with potentially less risk to hearing. More vestibulotoxic than cochleotoxic, gentamicin initially disrupts the endolymph-secreting vestibular dark cells, thereby preventing endolymphatic hydrops development. Following gentamicin application, both patients demonstrated a significant change in peripheral vestibular function, as characterized by a reduction of caloric response, impaired posturography performance, and reduced low-frequency gain on rotary chair testing. Posturography performance subsequently improved, confirming functional compensation. Both patients reported relief from vertiginous attacks. However, word recognition ability was significantly worse in one of these two patients. Changes in pure-tone thresholds were minimal.

[Effect of streptomycin placing in the fenestra of semicircular canals on the function and morphology of the normal and hydropic ears in guinea pigs]

The effect of streptomycin placed in the fenestra of lateral semicircular canal (LSC) on the function and morphology of the normal and artificial hydropic inner ears in guinea pigs was studied in order to explore the method and possibility of treating Meniere's disease by using aminoglycosides. After placing the drug in the fenestra of LSC, no change in AP threshold of ECochG in normal ears but an increase of that in hydropic ears were found caloric induced nystagmus in both groups were disappeared. Under light microscope, severe damage of vestibular epithelium of three canal cristae and utricular macula was noted, while no insult of cochlear hair cells was found in normal ears. More severe damage of vestibular epithelium with part of them degenerated and atrophied and lesions of cochlear hair cells in basal turns and part of second turns occurred in hydropic ears. These demonstrated that the ototoxicity of streptomycin was higher in hydropic ears than in normal ears. In order to destroy vestibular function and preserve cochlear function, further study for adequate dosage of streptomycin and correct route of administration is needed.

Sensorineural hearing loss of suspected autoimmune etiology: a report of three cases

The present paper reports three cases of sensorineural hearing loss of suspected autoimmune origin. Cases 1 and 2 were bilateral sensorineural hearing loss which responded to steroid therapy. Case 3 was bilateral fluctuant sensorineural hearing loss in conjunction with systemic lupus erythematosus. The pathogenesis of autoimmune sensorineural hearing loss is not yet fully understood. In two patients, hearing levels improved or stabilized following the use of osmotic expanders. The clinical results suggest that endolymphatic hydrops may participate in autoimmune sensorineural hearing loss.

Immediate and long-term effects of daily glycerol administration on guinea pig hydropic ears

Oral administration of glycerol at 0.5 g/kg and 1.0 g/kg body weight in the guinea pig with experimentally induced hydrops provoked no obvious modifications of the CAP audiogram within a 3-h recording session. Daily administration of glycerol at the same dose level during a 4-month period did not modify the deterioration of CAP thresholds although some limited beneficial effect was detected for some animals after 8 weeks of treatment.

Endolymphatic hydrops associated with otosclerosis

Endolymphatic hydrops (EH) associated with otosclerosis has been noted for many years. However, the causal relationship of these two entities remains controversial. Having reviewed the records of patients with otosclerosis describing fluctuant hearing loss and vertiginous symptoms, the authors found the EH may coexist with otosclerosis preoperatively; they may be two separate diseases that exist coincidentally; or EH may be caused by the otosclerotic process. Secondly, EH may occur with a fistula after surgery. Occurring after stapedectomy, EH may be caused by fistulization of the bony labyrinth, which is effectively treated by surgery to seal the fistula, which may cause EH to subside and hearing to improve. Thirdly, delayed EH may occur months or years after stapedectomy, possibly as a result of otosclerotic foci or surgical insult to the labyrinth. Dexamethasone, diuretics, and a room air rebreather can be used in the treatment of delayed EH. Hearing may be maintained or may deteriorate, but there usually is no dizziness. The clinical manifestations of EH associated with otosclerosis include a conductive or mixed type of hearing loss; the presence of fullness, tinnitus, fluctuation of hearing, episodic vertigo, an elevated negative summating potential (SP), and an increased summating potential:action potential (SP:AP) ratio shown by ECoG. This report presents five cases of EH associated with otosclerosis.

Shy-Drager syndrome presenting as Menière's disease

A 59-year-old patient with a history of Menière's disease is presented. She developed signs of progressive autonomic failure suggesting a diagnosis of Shy-Drager syndrome, a rare degenerative neurologic condition of unknown etiology. The most common otolaryngologic presentation of this syndrome is with stridor attributable to abductor paralysis of the vocal cords. The association with endolymphatic hydrops has not been previously described.