High-Resolution Computed Tomography of the Inner Ear: Effect of Otosclerosis on Cochlear Aqueduct Dimensions.

OBJECTIVES: The cochlear aqueduct is a bony duct connecting the scala tympani with the subarachnoid space. Given the pathophysiology of otosclerosis, including bone resorption and new bone deposition, we hypothesize that the cochlear aqueduct in otosclerotic ears is narrowed. METHODS: A retrospective review of patients with otosclerosis who have undergone high-resolution computed tomography (HRCT) of the temporal bone was completed. The control cohort included 20 patients with the diagnosis of noise-induced hearing loss, without the diagnosis of otosclerosis. Uniform measurements of cochlear aqueduct dimensions were performed using the axial plane. RESULTS: The otosclerosis cohort included 25 males and 52 females with mean age of 52.2 ± 17.6 years. The control group included 10 males and 10 females with mean age of 64.0 ± 18.5 years. The mean cochlear aqueduct length, width mid canal, aperture base, aperture widest diameter, and funnel diameter in millimeters were 12.19 ± 1.66, 0.68 ± 0.28, 4.21 ± 1.67, 3.23 ± 1.47, and 2.70 ± 1.05 in the ears with otosclerotic foci and 11.57 ± 1.66, 0.69 ± 0.29, 2.56 ± 1.59, 2.77 ± 1.67, and 2.58 ± 1.03 in control group, respectively. Statistical difference was seen in length of cochlear aqueduct, aperture base, and aperture widest diameters (P = .017, <.001, .007). CONCLUSIONS: The length of the cochlear aqueduct and the funnel width are statistically longer in the otosclerotic population compared to control. The width of the cochlear aqueduct is not statistically different.

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.

Sneezing and Perilymphatic Fistula of the Round Window: Case Report and Systematic Review of the Literature.

The goal of the present study was to describe a case of perilymphatic fistula (PLF) of the round window (RW) that occurred after sneezing, along with a review of the literature. We report a case of PLF of RW, which was provoked by sneezing, and its consequent medical and surgical treatments. With respect to the review of the literature, articles were initially selected based on their titles or abstracts, followed by methodological evaluation. The patient underwent an explorative tympanotomy (ET) with packaging of RW with the pericondrium, following which the patient's complaints regarding vertigo and imbalance disappeared, but the severe sensorineural hearing loss persisted. For the literature review, five references were selected. These studies showed a great variety in the clinical presentation and healing of symptoms. Sneezing represents a rare but well-recognized cause of PLF, as reported in our case. The correct selection of patients who should undergo ET and an early surgical repair of PLF are mandatory for better outcomes, especially in case of hearing.

Differences in perilymphatic space enhancement and adverse inflammatory reaction after intratympanic injection of two different gadolinium agents: A 9.4-T magnetic resonance imaging study.

PURPOSE: To compare the inner ear enhancement after intratympanic injection of two widely used gadolinium (Gd) agents by 9.4 T micro-magnetic resonance imaging (MRI) and to investigate the effects of Gd on the inner ear. METHODS: Twelve ears of six rats received intratympanic administration of 1/5 diluted Gd agents: gadoterate meglumine (Gd-DTPA) for the left ear and gadodiamide (Gd-DTPA-BMA) for the right ear. MRI was performed every 30 min from 1 to 4 h after administration. The normalized signal intensity was evaluated by quantitative analysis at each cochlear fluid compartment. Eight, six, and seven ears treated with Gd-DTPA, Gd-DPTA-BMA, and nothing as controls, respectively, were processed for histological evaluation after MRI. After hematoxylin & eosin staining, adverse inflammatory reactions were evaluated for turbid aggregation and lymphocytes. RESULTS: The perilymphatic enhancement of Gd-DTPA was superior to that of Gd-DTPA-BMA regardless of cochlear turn, compartment, and time point. Inflammatory reactions were found in 4/8 (50.0%) and 4/6 (66.6%) ears administered Gd-DTPA and Gd-DTPA-BMA, respectively. Regardless of the contrast agent used, inflammatory reactions were most definite in the scala tympani of the basal turn, i.e., near the round window. Slightly greater inflammatory reactions were observed in ears injected with Gd-DTPA-BMA compared to Gd-DTPA although the difference was not statistically significant. No inflammatory reaction was observed in any of the seven controls. The auditory brainstem response threshold was 11.8 ± 2.5 dB SPL before IT Gd injection and it did not change for up to 5 days (15.4 ± 6.6 dB SPL) post-injection. CONCLUSIONS: Gd-DTPA was superior to Gd-DTPA-BMA for visualization of the inner ear. Administration of diluted Gd agents intratympanically may induce considerable inflammatory reactions in the inner ear.

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.

A case of pneumolabyrinth induced by Eustachian tube air inflation.

OBJECTIVES: Here, we report a case of pneumolabyrinth induced by Eustachian tube air inflation (ETAI) with a catheter and present evidence that multiple air bubbles entered the perilymphatic space through a preexisting oval window fistula. SETTING: Tertiary referral center. PATIENT: Sixty-six-year-old woman. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Air bubbles in the perilymphatic space revealed by cone beam computed tomography (CT) volume rendering imaging. RESULTS: The patient was referred to us because of vertigo, unsteadiness, and right hearing loss after ETAI using a Eustachian tube catheter. On Day 2, an audiogram showed right total deafness, and the perilymphatic space could not be identified on T2-weighted magnetic resonance imaging. A high-resolution cone beam CT scan obtained on Day 3 showed multiple air bubbles in the labyrinth. The volume rendering images clearly revealed a larger air bubble in the vestibule inside the footplate of the stapes and small air bubbles in the horizontal semicircular canal, superior semicircular canal, and basal and second turns of the cochlea. This finding indicates that the air bubbles entered the perilymphatic space through an oval widow fistula caused by a sudden elevation in intratympanic air pressure. Two months later, the air bubbles had disappeared, and the patient's high tone hearing had improved slightly. CONCLUSION: ETAI can cause a pneumolabyrinth if the intratympanic pressure rises beyond a certain critical level. In this situation, volume rendering imaging of high-resolution cone beam CT can be used to quantify and identify the air bubbles present. The images taken in this study suggest that air bubbles entered the perilymphatic space through a perilymphatic fistula.

Traumatic perilymphatic fistula secondary to stapes luxation into the vestibule: a case report.

A penetrating ear injury with a perilymphatic fistula is not an uncommon occurrence in otolaryngologic practice, but stapes luxation is rare. We report the case of an 11-year-old boy who developed a traumatic perilymphatic fistula secondary to an atypical stapes luxation into the vestibule. After sustaining a penetrating injury to the right ear, the patient presented with otalgia, vertigo, vomiting, gait unsteadiness, and hearing loss. High-resolution computed tomography (HRCT) of the temporal bone detected pneumolabyrinth, indicating a perilymphatic fistula. The stapes had pivoted on the footplate at the oval window, and then it made an unusual 180° flip and luxated deeply into the vestibule, with the capitulum stapedis pointing medially. Conservative management was chosen in view of the high surgical risks posed by the deeply luxated stapes and the likelihood of a fracture of the stapes footplate. This case illustrates the importance of an accurate diagnosis and interpretation of a traumatic perilymphatic fistula and stapes luxation as seen on HRCT of the temporal bone.

Pólipo-quiste del seno esfenoidal como hallazgo casual en paciente con hipoacusia brusca severa retrococlear / Sphenoidal sinus-cyst as casual finding in a patient with severe and audden retrocochlear hearing loss

Presentamos el caso de una mujer de 56 años controlada en nuestro servicio de ORL, a causa de acúfenos y vértigo de aparición brusca. La exploración endoscópica fue normal. La audiometría mostraba una hipoacusia neurosensorial severa y los potenciales evocados auditivos (PEATC) confirmaron la citada hipoacusia apuntando un origen retrococlear de la misma. Como pruebas de imagen se solicitarion TC y RMN óticocraneal, en la que se informaba de la presencia de una lesión quística versus pólipo en seno esfenoidal de 15 por 10 mm sin otras alteraciones o patología significativa

We present the case of a 56 years old female controlled in our ENT Department because of right suden hearing loss, tinnitus and vertigo. The endoscopic exam was normal. Audiogram showed a severe neurosensorial hypoacusia and PEATC confirmed the so called hypoacusia suggesting a retrocochlear origin of it. As imaging tests and otic-craneal CT and IRM were asked for, which informed of the presence of a cystic lesion versus polyp in sphenoidal sinus of 15 x 10 mm without other alterations or significant pathology

Recurrent diving-related inner ear barotrauma.

OBJECTIVE: To present two cases of recurrent diving-related inner ear barotrauma (IEB) and to discuss the possible cause and pathogenesis of the increased inner ear vulnerability. STUDY DESIGN: Case series. SETTING: Tertiary referral center. PATIENTS: Two scuba divers suffering from repeated cochleovestibular barotrauma. INTERVENTIONS: Neurotological evaluation, perilymphatic fistulae repair, and conservative treatment. MAIN OUTCOME MEASURE: The increasing popularity of scuba diving expose the individuals involved in this sport to unique pathologies that are not common under terrestrial conditions. The otolaryngologist who is involved in the care of these patients is required to diagnose and treat diving-related ear injuries and to consider the risk for recurrent inner ear injury when diving is resumed. CONCLUSION: IEB carries a risk for permanent hearing loss and chronic vestibulopathy. We recommend complete neurotological evaluation including high-resolution CT of the temporal bones as a routine workup for IEB. The presence of a significant residual sensorineural hearing loss, evidence for noncompensated vestibular damage, and CT findings of possible enhanced cerebrospinal fluid-perilymph connection should be considered when a return to diving activity is considered.

Noise-induced perilymph fistula.

Perilymph fistulae are difficult to diagnose because they present with a wide variety of signs and symptoms, they are associated with many etiologies, and they often mimic other conditions. In this article, we describe a case of perilymph fistula that featured one of its more rare causes: acoustic trauma--specifically, damage from a loud blast from the siren of a fire engine. We also review the literature and discuss the difficulties of diagnosis and treatment and the possible mechanisms by which acoustic trauma and other etiologies cause perilymph fistulae.

Persistence of perilymph fistula mechanism in a completely paretic posterior semicircular canal.

The three dimensional eye movements (search coil technique) of a patient with a completely paretic left posterior semicircular canal as a result of a perilymph fistula (PLF) were studied. The patient still exhibited pressure induced nystagmus that obeyed Ewald's first law. This finding cannot be explained by otolith stimulation, but might indicate that PLF mechanisms either persist in canal plugging or act on the ampulla by directly deflecting the cupula.

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.

[Validation of a clinical scale for the diagnosis of perilymphatic fistula]. / Validation de l'echelle clinique pour le diagnostic des fistules périlymphatiques.

INTRODUCTION: The diagnosis of perilymphatic fistula (PLF) is difficult because no single clinical situation gives the diagnosis for sure. The goal of this article is to study the clinical situations where you must suspect a PLF and to support a clinical scale described in a previous work (Bussières et al 2003). METHODS: Retrospective study of 15 patients that had an exploratory tympanotomy with a PLF not confirmed preoperatively. An analysis of the symptoms, signs and complementary exams were done. The surgical technique and findings and the postoperative evolution were noted. RESULTS: There is 66.7% of hypoacusis the most frequently symptom (postoperative improvement of 26.7%); after came vertigo present in 60% (postoperative improvement of 44.4%) and tinnitus present in 53.3% (postoperative improvement of 25%). The trauma history is always positive, most of then is typical (80%) and the other one are atypical (20%).The diagnosis of PLF has been determined in 5 patients in the follow-up according to the improvement of the symptoms. These patients had a score > 7 at the clinical scale. CONCLUSION: The sensibility and specificity scores of the clinical scale are respectively 100% and 70% in this study.

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.