Anatomical Variations in Patients with Ménière Disease: A Tomography Study

Abstract Introduction The etiology of Ménière disease (MD), a difficult-to-treat condition with great morbidity, remains controversial in the literature. The possible clinical and diagnostic impact of anatomical variations of the temporal bone among patients with MD has been recently studied. Objective To identify anatomical variations of the temporal bone associated with the diagnosis of MD. Methods Thirty-seven patients were included, although each ear was considered separately (n = 74). A case group (nA = 33) was composed of the affected ears of patients with definiteMDand a control group (nB = 41) was used consisting of the ears of individuals who did not meet the criteria for MD and of the contralateral ears from patients with unilateral disease. Tomographic images from the individuals included in the study were submitted to a blinded and systematic evaluation regarding a broad variety of anatomical variations of the temporal bone. Obtained data were compared statistically between the groups and after stratifying the study sample. Significance level was set at 0.05. Results Among the affected ears, it was observed an increased number of tomographic scans in which the vestibular aqueduct could not be identified (p = 0.01, Fisher exact test). No statistically significant differences were observed when comparing the affected and contralateral ears frompatients with unilateral MD, between affected ears from patients with unilateral and bilateral disease or between contralateral ears of patients with unilateral affection and patients without the disease. Conclusion Some anatomical variations might be more frequent in the affected ears of patients with MD, such as the lower rates of individualization of the vestibular aqueduct.

Perilimphatic fistula test: a video clip demonstration.

Perilymphatic fistula (PLF) is an abnormal condition in which a communication is present between the perilymphatic space of the inner ear and the middle ear or mastoid, secondary to a dehiscence in the otic capsule, oval or round window. LF may induce hearing loss, tinnitus, aural fullness, vertigo, disequilibrium, or a combination of these symptoms; the vagueness of symptoms caused by PLF and the lack of specificity of clinical signs and symptoms make the diagnosis elusive. We report a video of a positive PLF test induced by the application of pressure on the tragus, just anterior to the left external auditory canal in a patient with cholesteatoma and PLF of lateral semicircular canal confirmed by CT scan imaging. https://www.youtube.com/watch?v=x5MhSILF9O4.

Radiological findings of the cochlear aqueduct in patients with Meniere's disease using high-resolution CT and high-resolution MRI.

The objective of the present study was to evaluate the cochlear aqueduct (CA) in Meniere's disease (MD) and to disclose radiological differences of CA between MD and non-MD patients by means of high-resolution computed tomography (HRCT) and high-resolution magnetic resonance imaging (HRMRI). Radiological data of 86 ears of MD patients which were separated into 52 ears of diseased side group (MD-D group) and 34 ears of contralateral non-affected side group of unilateral MD (MD-ND group), 27 ears of patients with sensorineural hearing loss (SNHL group) and 56 ears of patients with somatoform dizziness and normal hearing (control group) were analyzed retrospectively. The bony type of CA, the bony length of CA, and the bony width of CA medial orifice was measured in HRCT. The visibility of CA in HRMRI was scored. Fluid length in CA and fluid width in medial orifice were measured in HRMRI. Data were compared between MD-D, MD-ND, SNHL, and control group. There were no significant differences in the bony type of CA, bony length of CA, bony width of CA medial orifice, and fluid width of CA medial orifice between MD-D, MD-ND, SNHL and control group (p > 0.05). However, CA fluid length of MD-D (5.13 ± 1.88 mm) and of MD-ND group (5.44 ± 1.81 mm) was significantly shorter than fluid length of SNHL (6.90 ± 1.55 mm) (p < 0.001, p = 0.001) and of control group (7.43 ± 1.24 mm) (p < 0.001, p < 0.001). The ratio between CA fluid length and CA bony length was the smallest in MD-D group (0.403; p = 0.009). CA bony dimensions of affected ears of MD are normal, but CA fluid length is decreased.

An experimental study of inner ear injury in an animal model of eosinophilic otitis media.

CONCLUSION: As the periods of intratympanic injection of ovalbumin (OVA) to the middle ear became longer, marked eosinophil infiltration in the perilymphatic space was observed. Moreover severe morphological damage of the organ of Corti was observed in the 28-day antigen-stimulation side. These results indicate that eosinophilic inflammation occurred in the inner ear and caused profound hearing loss. OBJECTIVE: The purpose of the present study was to elucidate the inner ear damage in a new animal model of eosinophilic otitis media (EOM) which we recently constructed. METHODS: We constructed the animal model of EOM by intraperitoneal and intratympanic injection of OVA. Infiltrating cells and the inner ear damage were examined by histological study. RESULTS: In the inner ear, a few eosinophils were seen in the scala tympani of the organ of Corti and the dilation of capillaries of the stria vascularis was observed in the 7-day stimulation side. In the 14-day antigen stimulation side, some eosinophils and macrophages were seen in not only the scala tympani but also the scala vestibule. In the 28-day antigen-stimulation side, severe morphological damage of the organ of Corti and many eosinophils, red blood cells, and plasma cells infiltrating the perilymph were observed.

Ventriculoperitoneal shunt as treatment for perilymphatic fistula: a report of six cases.

We report six cases of perilymphatic fistula in patients who received ventriculoperitoneal shunts as part of their final mode of therapy. The last of our 6 patients actually received a ventriculoperitoneal shunt as her initial mode of therapy. All but one had benign intracranial hypertension. All six felt better (less disequilibrium, tinnitus, and pressure and occasional hearing improvement) after LP with removal of 15-20 ml of cerebrospinal fluid.

Sudden hearing loss due to large vestibular aqueduct syndrome in a child: should exploratory tympanotomy be performed?

A 16-year-old girl applied to our ENT clinic with a 3-day history of right hearing loss, tinnitus, and pressure in the right ear. She had had surgery for right perilymph fistula two times, one at the age of 7 and the second at the age of 9. She had recovered after both of these surgeries. This time she had exploratory tympanotomy and perylymh fistula was detected. Computerized tomography investigation obtained after 5 days postoperatively showed bilateral large vestibular aqueducts and otherwise normal inner ear structures. Thyroid function tests and neck palpation were normal. It was an unusual case with both large vestibular aqueduct syndrome (LVAS) and simultaneous spontaneous perilymph fistula.

Evaluating patients with vertigo: bedside examination.

Dizziness and vertigo are common complaints in patients referred for neurological evaluation. With a basic understanding of vestibular physiology and proper examination techniques, a correct diagnosis can generally be made at the bedside. This article reviews the most common peripheral and central vestibular syndromes as well as the key elements of the bedside vestibular system examination.

Can low frequency sound stimulation during posturography help diagnosing possible perilymphatic fistula in patients with sensorineural hearing loss and/or vertigo?

Perilymphatic fistula (PLF) is often difficult to diagnose because of the similar symptomatology, such as vertigo, tinnitus and hearing loss, which is found in several inner ear diseases. We attempted to correlate a positive result of low frequency sound (LFS) stimulation tests in posturography with the presence or absence of a PLF confirmed by transtympanic endoscopy in 209 patients with various inner ear diseases (Meniere's disease ( n=128), vestibulopathy ( n=41), cochleopathy ( n=28) and sudden deafness ( n=12). LFS provoked unsteadiness in posturography without PLF in 24 patients with Meniere's disease, in 5 patients with vestibulopathy, in 3 patients with cochleopathy and in 2 patients with sudden deafness. In one patient, tympanoscopy revealed fistula in the round window membrane that was covered with a fibrinous layer. In four cases there was abnormal light reflex in the round window but without PLF. In eight cases, Hennebert's sign was present with nystagmus, without PLF. We conclude that pathological responses to the LFS test in posturography can also be encountered in other inner ear diseases without PLF.

Contrast enhancement of the cochlear aqueduct in MR imaging: its frequency and clinical significance.

There have been no previous reports on contrast enhancement of the cochlear aqueduct in magnetic resonance imaging. The purpose of the present study was to evaluate the frequency and significance of this finding. Thirty-one patients (15 men and 16 women; age range 18-81 years) with otologic symptoms (sudden sensorineural hearing loss, vertigo, or tinnitus) were examined using contrast-enhanced imaging on a 1.5-T MR scanner. The normal ear served as the control. Two radiologists evaluated contrast enhancement in the area of the cochlear aqueduct. Forty-eight of 62 ears (77.4%) showed contrast enhancement of the cochlear aqueduct, but no significant differences in the frequency of contrast enhancement were observed between patients with and patients without vertigo, tinnitus, sensorineural hearing loss, cerebellopontine angle tumors, or a high-riding jugular bulb. In addition, no gender- or age-related differences were noted. Contrast enhancement of the cochlear aqueduct was frequently observed, but the frequency of enhancement in symptomatic ears was not significantly higher than in control ears. The results of this study may prove helpful in avoiding unnecessary examinations and potential diagnostic confusion.

[When to suspect a perilymphatic fistula?]. / Quand suspecter une fistule périlymphatique?

INTRODUCTION: The diagnosis of perilymphatic fistula (PLF) is difficult since no single clinical situation gives the diagnosis for sure. The goal of this study is to clarify the clinical situations where you must suspect a PLF. METHODS: Retrospective study of 20 patients that had an exploratory tympanotomy with a PLF confirmed peroperatively. An analysis of the symptoms, signs and complementary exams was done. The surgical findings and the postoperative evolution were noted. RESULTS: 100% of patients reported a hearing loss, 80% vertigo, 70% a tinnitus and 35% equilibrium problems. Every patient had an etiological event to explain the PLF (trauma 85%), stapedotomy (10%), other ear surgeries. Five patients had a positive fistula or Vasalva test. All patients except one had an hearing loss on the audiogram (sensorineural, mixte or conductive). 50% had a CT scan, 70% of which were abnormal. A VNG was done on 3 patients. The sites of the PLF were as follows: 90% oval window, 5% round window and 5% both windows. The hearing got better or was stabilised in 95% of patients after the operation. 64% saw an improvement of their tinnitus and 87% of their vertigo. CONCLUSION: The diagnosis of PLF is difficult and a high index of suspicion is mandatory. One must look for an etiologic situation to explain the PLF. The audiogram is almost always modified, a mixte hearing loss being common due to the high incidence of ossicular trauma associated with PLF. The clinical clinical situations where you must suspect a PLF were identified as follows: An old trauma, a recent trauma, a history of otologic surgery particularly on the stapes and a preexisting hearing loss that aggravates. A diagnosis scale to evaluate the risk of PLF, based on clinical situations, physical exam and complementary exams was done to help the clinician in the evaluation of PLF.

[Perilymphatic fistula: report of a case which resolved spontaneously in five days and literature review]. / Fístula perilinfática: presentación de un caso con resolución espontánea en cinco días y revisión de la literatura.

AIMS: We report a patient with a perilymphatic fistula and review the literature on this topic. CASE REPORT: The patient was a 50 years old male with a five days history of intense and continuous vertigo associated with nausea, vomiting and sweating, which was initiated after a sudden noise in the left ear. The symptoms resolved spontaneously over five days, without surgical treatment. The clinical picture resembles those previously reported for perilymphatic fistula. The current literature on this topic has been reviewed in this article. CONCLUSION: The patient presented an early recovery, what corroborates the current tendency of waiting a few weeks before indicating surgery.

[Inner ear and subarachnoid spaces: relations and diseases]. / Oreille interne et espaces sous-arachnoïdiens.

The purpose of this article is to describe, with 5 clinical cases, the physiological communications between the inner ear and the subarachnoid spaces (SAS) and present the imaging features with regard to. Therefore we briefly illustrate abnormal communications between SAS and perilymphatic fluids in certain cochlear and internal acoustic meatus (IAM) malformations and their consequences. Imaging features may depict diffusion pathway of bacterial meningitis to membranous labyrinth via the cochlear aqueduct or via the IAM. Rarely, in some patients referred for cochleovestibular symptoms, imaging features may display skull base tumors involving the area of cochlear or vestibular aqueduct aperture. Therefore, in patients referred for cochleovestibular symptoms, MR and CT study should carefully scrutinise not only the IAM but also the aperture of the cochlear and the vestibular aqueducts and the cerebellopontine meninges.

MR cisternography of the cerebellopontine angle: comparison of three-dimensional fast asymmetrical spin-echo and three-dimensional constructive interference in the steady-state sequences.

BACKGROUND AND PURPOSE: MR cisternography has been used as the noninvasive screening tool of the cerebellopontine angle. The purpose of this study was to directly compare two currently dominant types of sequences for heavily T2-weighted MR cisternography. METHODS: Three-dimensional fast asymmetric spin-echo (3D-FASE) sequences, which are 3D half-Fourier rapid acquisition with relaxation enhancement and 3D constructive interference in the steady-state (3D-CISS) sequences, were compared on a clinical 1.5-T MR unit using the same scan times. In five healthy volunteers, the contrast-to-noise ratio (C/N) between CSF and the cerebellum was measured at three locations. Then, for qualitative analysis, the quality of the labyrinth was scored on the original source multiplanar reformatted images, the virtual endoscopic images, and the maximum intensity projection (MIP) images. In 20 consecutive patients with suspected cerebellopontine angle tumors, visualization of the tumors was evaluated using 3D contrast-enhanced spoiled gradient-echo imaging as the standard of reference. RESULTS: Both sequences showed comparable mean C/N values; however, in qualitative analysis, the scores for 3D-CISS on the source, virtual endoscopic, and MIP images were significantly lower than those on the images obtained with 3D-FASE, owing to more prominent flow and magnetic susceptibility artifacts on the 3D-CISS sequences. In all subjects, discontinuity of the semicircular canals was seen on the virtual endoscopic and MIP images obtained with 3D-CISS, owing to susceptibility artifacts, but not on those obtained with 3D-FASE. All 12 tumors were detected by both sequences, but 3D-CISS gave one false-positive result. CONCLUSION: 3D-FASE is considered the method of choice because artifacts are reduced and specificity is increased.

Temporal bone findings in multiple endocrine neoplasia type 2B.

To our knowledge, present case is the first published report of temporal bone findings in multiple endocrine neoplasia type 2B (MEN-2B). We describe a 43-year-old Japanese man with medullary thyroid carcinoma (MTC), pheochromocytoma, mucosal neuroma and a Marfanoid body habitus. The collateral adrenal tumors and MTC were removed surgically. However, 14 years after surgery, the MTC and pheochromocytoma recurred and the patient died of intracranial hemorrhage due to hypertension. During the autopsy, metastatic MTC was detected in the liver, lungs, kidneys, pancreas and cervical lymph nodes. Recurrent pheochromocytoma was present in the right kidney. Mucosal neuromas were found in the tongue, gastrointestinal tract and vesical nerve plexus. The following histopathological findings were seen in both temporal bones: metastatic MTC was found as well as neuromas and the cochlear aqueduct was widely patent.

Tratamiento quirúrgico del vértigo: revisión bibliográfica / Surgical treatment of vertigo: a review

Se hace una revisión bibliográfica crítica de los procedimientos quirúrgicos usados para curar el síntoma vértigo, con objeto de aclarar sus indicaciones en función de resultados y de efectos nocivos. Las conclusiones a que se llegó fueron las siguientes: 1. En el vértigo producto de fístula perilinfática, se debe intervenir quirúrgicamente tan pronto sea diagnosticada y aún en casos de que solo exista una razonable sospecha. 2. En el vértigo postural paroxístico benigno incapacitante y resistente a tratamiento médico y rehabilitación física, se puede intervenir con obliteración del conducto semicircular posterior, informando al paciente, de preferencia por escrito, que existe riesgo, aunque poco probable, de que aparezca hipoacusia y acúfeno. 3. El vértigo ocasionado por la enfermedad de Meniére o por otros padecimientos, en caso de ser incapacitante y no susceptible a tratamiento médico, debe intervenirse siguiendo dos criterios: Cuando la audición ha disminuido hasta el punto de ya no ser útil, se puede emplear la gentamicina intratimpánica o la derivación del saco endolinfático; si estas fracasan, debe efectuarse laberintectomía. Cuando hay buena audición, o audición recuperable con auxiliar auditivo se puede hacer derivación del saco endolinfático; si ésta fracasa, neurectomía vestibular. 4. Hay razones para ser escéptico sobre la existencia y sobre la posibilidad diagnóstica del vértigo como producto de compresión vascular al tronco del nervio octavo, por lo que la descompresión microvascular del nervio debe considerarse como en fase experimental, y no efectuarse en ambiente clínico.

Beta-2 transferrin assay in the identification of perilymph.

HYPOTHESIS: Western blot assay for beta-2 transferrin protein is a clinically useful method for the detection of human perilymph and should be used for the diagnosis of perilymph fistulas (PLFs). BACKGROUND: Considerable controversy exists regarding the diagnosis of PLF. Recent studies suggest that the detection of beta-2 transferrin protein may be useful in the identification of perilymph. METHODS: To evaluate the usefulness of the beta-2 transferrin assay for identifying human perilymph, paired perilymph samples and negative controls were collected on Gelfoam pledgets from 20 patients who had surgery that opened the inner ear. Blinded immunoelectrophoretic assay (Western blot) for beta-2 transferrin was performed on each specimen. RESULTS: Only one (5%) of the known perilymph samples and none of the control specimens were definitely positive for beta-2 transferrin. Combined with historical data, this assay has 29% sensitivity, 100% specificity, 100% positive predictive value, and 31% negative predictive value. CONCLUSIONS: These findings suggest that the beta-2 transferrin protein assay may not be a reliable method for detecting human perilymph when performed using this technique.

Sudden hearing loss: frequency of abnormal findings on contrast-enhanced MR studies.

BACKGROUND AND PURPOSE: Our purpose was to determine the frequency of abnormal findings on contrast-enhanced high-resolution MR imaging studies in patients with sudden hearing loss. METHODS: Seventy-eight consecutive patients with sudden hearing loss underwent contrast-enhanced MR imaging of the temporal bone, cerebellopontine angle, and brain. Additional tests included audiologic examination, electrocochleography, fistula tests, and serologic tests for viral agents and autoimmune disorders. RESULTS: Probable causes of the sudden hearing loss in these patients included viral or immune-mediated disease, Meniere disease, vascular disorder, syphilis, neoplasm, multiple sclerosis, and perilymphatic fistula. Twenty-four (31%) of the 78 patients were found to have abnormal imaging results early in the course of their work up and treatment. CONCLUSION: The prevalence of abnormal findings on contrast-enhanced MR studies is higher than previously reported in patients with sudden hearing loss.

The cochlear aqueduct: an important landmark in lateral skull base surgery.

The cochlear aqueduct (CA) is used as a landmark in lateral skull base surgery. In this study anatomic relationships between the CA and adjacent neurovascular structures were examined by dissecting 32 temporal bones. Observations of the relationship of the external opening (EO) of the CA with the ninth, tenth, and eleventh cranial nerves, inferior petrosal sinus (IPS), and intrapetrous carotid artery (ICA) were noted. In addition to the distance of the EO of the CA to the vertical portion of the ICA, the entire length of the CA and the width of the EO were also measured. The ninth nerve was the only structure lodged at the EO of the CA in 34.4% of bones. However, in 40.6% of bones only the IPS crossed the EO of the CA, although the ninth nerve was situated just anteroinferiorly in the vicinity of the EO. In 15.6% of bones it was possible to observe both the ninth nerve and the IPS crossing the EO. In 9.4% of bones the EO of the CA was found to be occupied by the tenth and eleventh nerves. It was also observed that the ICA was located anteriorly on the same sagittal plane with the EO in 15.6% of bones. It was concluded that although in 90% of cases the EO of the CA was in close relation with the ninth nerve, other structures such as the IPS, the tenth and eleventh cranial nerves, and the ICA were also at risk during drilling in this area because of their intimate relationships with the EO of the CA.

The cochlear aqueduct in pediatric temporal bones.

The cochlear aqueduct is a bony channel which contains the fibrous periotic duct and connects the perilymphatic space of the basal turn of the cochlea with the subarachnoid space of the posterior cranial cavity. Previous histological studies suggested that patency depended on age, whereas a more recent study showed no statistical correlation between age and patency. To clarify patency in pediatric cochlear aqueducts, we selected 21 temporal bones from 12 infants and children, varying in age from birth to 9 years, in which the cochlear aqueduct was fully visible on one histological section. Photographs were taken for documentation and the length and width of the orifice of the external aperture of the aqueduct at the scala tympani were measured and followed to the internal aperture at the subarachnoid space. The lumen of the duct was examined for mononucleated cells, blood cells and fibrous tissue. Measurements revealed that the mean length of the cochlear aqueduct was 4.6 mm (range, 2.4-10.7 mm), mean width of the external aperture was 484 microm (range, 225-869 microm), and mean width of the internal aperture was 1293 microm (range, 699-2344 microm). The mean diameter of the narrowest part (isthmus) was 151 microm (range, 75-244 microm). In all temporal bones the cochlear aqueduct was patent, with one exception. This latter temporal bone was from a 2-month-old girl with multiple intralabyrinthine anomalies, with the missing cochlear aqueduct believed to be due to an aplasia. Our results support prior measurements of the cochlear aqueduct and demonstrate a short and patent cochlear aqueduct in newborns. With growth, a significant increasing length of the duct was found.

Perilymph detection by beta 2-transferrin immunoblotting assay. Application to the diagnosis of perilymphatic fistulae.

beta 2-Transferrin, the asialotransferrin, is found in cerebrospinal fluid (CSF) and inner ear perilymph, but is absent from serum and other body fluids or secretions except the aqueous humor. The detection of this asialo-fraction of the transferrin in ear fluid microsamples with an immunoblotting technique is of great interest when a perilymphatic fistula (PLF) is suspected. beta 2-Transferrin was detected on microsamples collected by syringe or on micro-collagen sponges from 30 patients undergoing ear surgery. The problem is reviewed, the technique and sample preparation are explained and the results discussed. beta 2-Transferrin detection in the ear fluid allows the identification of perilymph, except in the CSF oto- or rhinorrheal context, and is proposed as a promising test to confirm perilymphatic fistula.