The Role of Endolymphatic Hydrops in Patients with Pantonal Idiopathic Sudden Sensorineural Hearing Loss:A Cause or Secondary Reaction

The purpose of this study was to investigate the presence of endolymphatic hydrops(EH)in both affected and unaffected ears of patients with pantonal unilateral idiopathic sudden sensorineural hearing loss(ISSNHL)using three-dimensional fluid-attenuated inversion recovery magnetic resonance imaging(3D-FLAIR MRI)and further evaluate the significance of EH in this disorder.Twenty-seven ISSHL patients were enrolled in this study.3D-FLAIR MRI was performed 24 h after intratympanic injection of gadolinium-diethylenetriaminepentaacetic acid(Gd-DPTA).The incidences of EH in the affected ears and contralateral unaffected ears were compared and the correlations of EH with vertigo or prognosis were analyzed using the Chi-square test.The results showed that the incidence of EH was 68.0%(17/25)in the affected ears and 34.8%(8/23)in the unaffected ears.There was a statistically significant difference between affected ears and unaffected ears in regard to the incidence of EH(P<0.05).There were no significant correlations of EH with vertigo(P=1.000)or with prognosis(P=0.359)in the affected ears.In conclusion,there is EH in the inner ear of patients with pantonal ISSNHL;EH is not related to vertigo,a concomitant symptom of ISSNHL,and the prognosis of this condition.The presence of EH may be a secondary reaction following the impairment of the inner ears with pantonal ISSNHL.

Dexamethasone does not affect endolymphatic hydrops(EH)in patients with Meniere's disease within 24 h,and intratympanic administration of gadolinium plus dexamethasone simplifies high-quality imaging of EH using a novel protocol of 7 min

Background:Intratympanic administration of gadolinium chelate allows for a better visualization of endolymphatic hydrops(EH)using MRI than intravenous injection and was recently further improved to facilitate high-quality imaging of EH in 7 min.The aim of the present study was to simplify the intratympanic administration protocol by mixing gadolinium chelate with therapeutic dexamethasone and to evaluate the effects of this mixture on the visualization of EH in MRI.Materials and methods:In an in vitro study,the potential impact of gadolinium-diethylenetriamine pentaacetic acid(Gd-DTPA)on the stability of dexamethasone was evaluated by analyzing dynamic changes in dexamethasone with high-performance liquid chromatography(HPLC)after mixing with GdDTPA.Ten patients with definite Meniere's disease(MD)were recruited to study the potential interference of dexamethasone on MRI visualization of EH,and 49 patients with MD were recruited to evaluate the effect of intratympanic injection of Gd-DTPA mixed with dexamethasone on MRI of EH using a 3T MR machine and a novel heavily T2-weighted 3-dimensional fluid-attenuated inversion recovery reconstructed using a magnitude plus zero-filled interpolation(hT2FLAIR-MZFI)sequence.Results:The retention times and peak area of dexamethasone in HPLC were not modified by the addition of Gd-DTPA.EH grading in the cochlea and vestibule was not influenced in any ear by intratympanic injection of dexamethasone.Excellent inner ear images were obtained from all patients,and EHs with various grades were displayed.There were significant correlations between diagnosis and cochlear EH(p<0.01,Spearman's Rho),between diagnosis and vestibular EH(p<0.01,Spearman's Rho),and between cochlear and vestibular EH(p<0.01,Spearman's Rho).The distribution of Gd-DTPA plus dexamethasone negatively correlated with the grade of vestibular EH.Injury of the endolymph-perilymph barrier was detected in one cochlea and three vestibules of 59 inner ears with MD.Conclusions:Intratympanic administration of Gd-DTPA plus dexamethasone yielded high-quality MRI images of EH in patients with MD using a novel 7-min protocol and simplified the clinical application.Intratympanic administration of Gd-DTPA plus dexamethasone might be used to test its therapeutic effect in future work.

Correlation of semi-quantitative findings of endolymphatic hydrops in MRI with the audiometric findings in patients with Meniere's disease

Purpose:To investigate the correlation between vestibular hydrops(VH),cochlearhydrops(CH),vestibular aqueduct non-visibility(VANV),and visually increased perilymphatic enhancement(VIPE)with the findings of pure-tone audiometry(PTA)in Meniere’s disease(MD)patients.Methods:In this cross-sectional study,53 ears belonging to 48 patients were divided into two groups and evaluated.In group“MD patients,”there were 24 ears of 19 patients diagnosed with the definite MD(14 patients with unilateral and 5 patients withbilateral involvements).The“control group”consisted of 29 non-symptomatic ears belonging to patients diagnosed with unilateral sudden sensory-neural hearing loss or unilateral schwannoma.All the patients underwent 2 sessions of temporal bone MRI using the same 3T system:an unenhanced axial T1,T2,and 3D-FLAIR MRI,an intravenous gadoliniumenhanced axial T1 fat-sat,and 4 h after the injection,an axial 3D-T2 cube and 3D-FLAIR session.VH,CH,VANV,and VIPE were assessed.Subsequently,the correlation between EH indices and PTA findings(in three frequency domains of low,middle,and high)were evaluated,and the predictive value of MRI was calculated.Results:VH was significantly correlated with the hearing threshold in the low,middle,and highfrequency domains.CH was also correlated with the hearing threshold in the low and middle domains.Contrarily,VIPE was not associated with hearing thresholds,and VANV was only correlated with the hearing threshold in low frequencies.Conclusion:The grade of VH,CH,and VANV were significantly correlated with the hearing thresholds in PTA.

Contralateral delayed endolymphatic hydrops: Clinical features and long term outcome

Background:Contralateral delayed endolymphatic hydrops(CDEH)is a clinical entity characterized by fluctuating low frequency hearing loss and/or vertigo,mimicking Meniere’s disease(MD),that manifests after the appearance of severe non-hydropic hearing loss(NHHL)at the other ear.Objectives:to describe the clinical features and the course of 57 patients affected by CDEH.Method:this is a retrospective study;57 patients affected by CDEH,out of 1065 patients seen in the same period and affected by MD,were subjected to otoscopy,PTA threshold evaluation,impedance testing,ABR,research of positioning nystagmus,vestibular function evaluated by means of bithermal caloric test under video-oculographic,and MRI with gadolinium.Results:the CDEH was definite in 24 cases(42%),probable in 2(4%)and possible in 31(54%).The mean PTA threshold at the hydropic ear was 41 dB.At the last follow-up,40 patients(70%)did not report vertigo or fluctuating hearing loss.Among the 17 patients who still reported symptomatology,11(64%)were affected by fluctuating hearing loss alone,4(23%)reported a subjective worsening of hearing loss and 2(12%)an acute vertigo crisis.Conclusions:contralateral delayed endolymphatic hydrops is a relatively rare form of Meniere disease that manifests more frequently as a definite form or with fluctuating low-frequency hearing loss.The prognosis at a long term follow-up is relatively good in terms of vertigo resolution.Contralateral delayed endolymphatic hydrops rarely determines a severe hearing loss in the better ear.

MRI detection of endolymphatic hydrops in Meniere's disease in 8 minutes using MIIRMR and a 20-channel coil after targeted gadolinium delivery

Background:Endolymphatic hydrops(EH)become visible in vertigo patients,particularly in those with Meniere's disease(MD),in vivo using gadolinium-enhanced MRI.However,the image quality is not satisfying after intravenous injection of gadolinium chelate(GdC),and occasional failure in GdC uptake has been noticed after traditional intratympanic injection.In the present report,targeted delivery of GdC and using a cost-effective MRI system to obtain high quality images of EH in only 8 min will be fntroduced.Methods:39 MD patients were recruited in the study.First,0.1 ml of 20-fold diluted gadolinium-diethylenetriamine acid(Gd-DTPA)was delivered onto the posterior upper part of the tympanic medial wall using a soft-tipped micro-irrigation catheter through an artificially perforated tympanic membrane.Inner ear MRI was performed 24 h after Gd-DTPA administration using a 3T MR machine and a 20-channel head/neck coil with an 8 min sequence of medium inversion time inversion recovery imaging with magnitude reconstruction(MIIRMR).The parameters were as follows:TR 16000 ms,TE 663 ms,inversion time 2700 ms,flip angle 180°,slices per slab 60.Results:Efficient inner ear uptake of Gd-DTPA was detected 24 h after delivery and it created excellent contrast in the inner ear of all cases.High quality images demonstrating EH in the vestibule and cochlea were obtained.Conclusion:Targeted delivery of minimum Gd-DTPA(0.1 ml,20-fold dilution)onto the posterior upper portion of the tympanic medial wall and MRI with MIIRMR in a 3T machine and 20-channel head/neck coil are clinically practical to obtain high quality images displaying EH.

Diuretic Agents in Treatment of Sudden Deafness

Objective To study the role of diuretic agents in treating sudden deafness (SD) and explore the possibility of endolymphatic hydrops as a potential cause of SD. Methods Twenty-eight SD cases were reviewed. In 23 cases, treatment was initiated with routine agents. Diuretic agents were later added in 8 of these cases that failed to respond to routine treatment agents. Diuretic agents were included in the initial treatment in the rest 5 cases. In total, 13 cases received diuretics in addition to routine treatment agents and 15 cases received conventional treatment only. Results In the 8 cases who received diuretics after failed conventional treatments, 4 showed hearing improvement, whereas all 5 cases in which diuretics were included in the initial treatment demonstrated hearing improvement. Conclusion These results suggest a possible role of endolymphatic hydrops in the pathophysiologic course of SD. Diuretics should be considered when clear indications exist with no conflicts to other medical conditions.

Morbus Menière: Were the last 50 years of molecular biological research fruitless for Menière's disease?

After discovering an inner ear hemorrhage, Prosper Menière ascribed disease to the inner ear for the first time. Since that time, a lot of efforts have been made to determine the pathophysiologic causes of the classical symptoms sensorineural hearing loss, vertigo attacks, tinnitus and ear fullness. According to its express pattern Menière's disease may appear as classical andatypical disease. In the last decades, huge advances have taken place in biochemical and physiological research and in pathophysiological understanding of the inner ear and its diseases. This encloses stimulus perception and conduction, regulation of inner-ear fluid homeostasis and inner ear diseases with underlying genetics. Menière's disease pathophysiologic correlate is an endolymphatic hydrops which is characterized by changes of inner ear homeostasis with its parameters volume, concentration, osmolarity and pressure of the endolymph. Hormones, autonomous system and the immunsystem together with purinergic, adrenergic and muscarinic receptors, steroids, vasopressin, atrial natriuretic peptide and aquaporin channels regulate inner ear homeostasis. Consequently, general diagnostics comprise a magnetic resonance imaging with gadolinium, vestibular diagnostics and tone audiometry. Standard therapy for acute inner ear symptoms is limited to cortisone infusions together with a rheologic agent or a radical scavenger. For acute vertigo attacks and for the mainstay therapy antivertiginous pharmaceuticals are given. In severe cases destruction of the vestibular hair cells by ototoxic antibiotics, endolymphatic sac surgery or neurectomy of the vestibular nerve might be necessary. Certainly, in research there is a move from simple pharmaceutical therapy forward to nanoparticlebased, genetic-based and stem cell therapy.