The role of explorative tympanotomy in patients with sudden sensorineural hearing loss with and without perilymphatic fistula.

PURPOSE: The purpose of this study was to describe the role of explorative tympanotomy in patients with Profound Sudden Sensorineural Hearing Loss (SSNHL) without clinical evidence of perilymphatic or labyrinthine fistula and to compare intraoperative findings with the postoperative hearing outcome. STUDY DESIGN: Retrospective study of all patients diagnosed with SSNHL who underwent explorative tympanotomy between 2002 and 2005. SETTINGS: Tertiary care university-affiliated hospital. SUBJECTS AND METHODS: Eighty-two patients were diagnosed with unilateral profound SSNHL and underwent tympanotomy with sealing of the round and oval windows. Values of pure tone audiograms and percentage hearing loss of patients with and without intraoperative diagnosed perilymphatic fistula (PLF) were compared and analyzed. RESULTS: PLF was diagnosed in 28% cases intraoperatively. In most cases, hearing improved significantly after surgery. Interestingly, patients with PLF had a 2.4 times greater decrease of percentage hearing loss compared to patients without PLF. CONCLUSIONS: Explorative tympanotomy seems to be useful in patients with profound SSNHL. Patients with PLF benefit more from the surgical procedure and have better outcome than patients without PLF.

Hearing loss after lumbar puncture.

We report a 63-year-old man who developed transient acute on chronic hearing loss after a lumbar puncture performed to investigate raised intracranial pressure. He was subsequently found to have stenosis of the distal left transverse sinus, which was treated with stenting.

Communication routes between intracranial spaces and inner ear: function, pathophysiologic importance and relations with inner ear diseases.

OBJECTIVE: There exist 3 communication routes between the intracranial space and the inner ear, the vestibular aqueduct, the cochlear aqueduct, and the internal auditory canal. They possess a key role in inner ear pressure regulation and fluid homeostasis and are related to inner ear diseases. REVIEW METHODS: Relevant literature was reviewed, and the current knowledge of the anatomy, physiologic importance, and relations to inner ear diseases were described. Pathologic communication routes such as semicircular canal dehiscence syndrome were highlighted as well. CONCLUSION: Abnormalities in all 3 communication routes may predispose or be the cause of distinct inner ear pathologic condition and involved in other cochlear and vestibular syndromes, in which their role is not completely clear. The increasing knowledge of the underlying mechanisms encourages promising approaches for possible intervention in the future.

Management of the draining ear in children.

There are a variety of causes of otorrhea in children. The most important factor in reaching the proper diagnosis and providing relief of the problem is aural toilet. Once adequate debridement has been performed, the diagnosis is usually clearer, and treatment with ototopicals is significantly more effective. Most cases of otorrhea are due to infection or granulation tissue and can be managed initially with appropriately selected ototopical medication, thereby avoiding the risks and side effects of systemic therapy and the need for referral to a specialist. However, otorrhea in children that is refractory to medical therapy may be due to retained tympanostomy tubes or insidious pathology such as cholesteatoma or malignancy. In such cases, prompt referral to the otolaryngologist can facilitate accurate diagnosis and successful management.

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.

Perilymphatic application of alpha-melanocyte stimulating hormone ameliorates hearing loss caused by systemic administration of cisplatin.

It has previously been demonstrated that ototoxicity induced by systemic administration of cisplatin is reduced by concomitant systemic administration of alpha-melanocyte stimulating hormone (alpha-MSH). In this study we investigated the effects of cochlear, perilymphatic application of alpha-MSH during intraperitoneal administration of cisplatin. Guinea pigs, implanted with a round-window electrode, allowing daily monitoring of the compound action potential (CAP), and also implanted with a mini-osmotic pump, pumping at a rate of 0.25 microl/h either physiological saline or alpha-MSH solution (0.02, 2, and 20 microg/ml), were treated daily with a bolus injection of cisplatin (2 mg/kg) until the electrocochleogram showed a persistent decrease in CAP amplitude (> or = 40 dB threshold shift at 8 kHz). Then, cisplatin treatment was stopped, but intracochlear perfusion of alpha-MSH or physiological saline was continued for 10 days to evaluate possible effects of alpha-MSH on the expected recovery. On day 10, the animals were killed and the cochleas were fixed and processed for histological analysis. All groups required 6-7 days of cisplatin to reach the criterion CAP threshold shift. Ten days after cessation of the cisplatin treatment, recovery of the CAP was observed in all groups and at all frequencies, although it was more pronounced at the lower frequencies. With respect to recovery, small statistically significant differences were found between the saline and the alpha-MSH co-treated groups. Histological results showed significantly less outer hair cell (OHC) loss in the group co-treated with 2 microg/ml alpha-MSH as compared to the group co-treated with saline. Since alpha-MSH was directly delivered to the cochlea, the ameliorating effect of alpha-MSH on OHC survival is likely to involve a cochlear target.

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.

[Etiology of labyrinthine perilymphatic fistula]. / K voprosu ob étnologii perilimfaticheskikh fistul labirinta.

The examination of 120 patients with verified labyrinthine fistulas (LFs) has demonstrated that perilymphatic LFs most often are caused by rupture of the cochlear window's membrane (54%). Among other reasons were broken base of the stapes (6%), the defect in the area of both windows (17%), rupture of the annular ligament of the stapes (15%), defects in the area of semicircular canals. Incompetence of the stapedial piston prosthesis is documented.

Endoscope-guided round window fistula repair.

OBJECTIVE: Endoscope-guided round window membrane repair was performed to evaluate whether the approach is feasible in the treatment of a round window fistula. STUDY DESIGN: Retrospective case review. SETTING: Tertiary care academic center. PATIENT: A 27-year-old man had been scuba diving 6 days previously in the Australian Great Barrier Reefs. He had poor hearing with tinnitus in the left ear and a vertiginous sensation. INTERVENTION: A myringotomy was incised, and a tympanoscope was introduced into the middle ear cavity. With the patient under general anesthesia, the middle ear and the oval and round window areas were examined with a tympanoscope. In endoscopic visualization, a round perforation could be seen in the round window membrane. After detection of the round window perforation, a small piece of temporal fascia was obtained to seal the membrane perforation. RESULTS: One month after the operation, the patient's hearing was significantly better. The myringotomy had healed. CONCLUSION: A transmyringeal endoscopic procedure for round window fistula repair is feasible and combines the best features of minimally invasive surgery and aural endoscopy.

Tympanic membrane displacement analyser tracing modifications induced by glycerol in Menière's disease.

The aim of the study was to detect inner ear fluid pressure changes induced by glycerol in Menière's disease (MD) by means of a tympanic membrane displacement analyser (TDA). The study group consisted of 25 MD patients. The Vi (maximum inward displacement of the tympanic membrane) and the Vm (mean displacement of the tympanic membrane) were measured at 10, 20 and 25 dB above the stapedial reflex threshold. Each patient received therapy based on glycerol. The control group consisted of 20 patients with non-hydropic sudden hearing loss. At 20 and 25 dB above stapedial threshold MD patients had lower Vi values before therapy. After glycerol, we observed a Vi increasing in the hydropic ears in 68-96 per cent of patients. Since a Vi improvement implies a reduction of perilymph pressure, our results confirm the effectiveness of Vi in detecting specific action of glycerol in MD.

Relationship of the cochlear aqueduct and inner ear pressure in Ménière's disease and in a normal population.

OBJECTIVE: The aim of this study was to determine the dimensions of cochlear aqueduct radiologically in patients with Ménière's disease and in normal subjects, and to correlate these findings with normal and low static acoustic compliance (SAC) (high and normal perilymphatic pressure) to see whether the dimensions of the cochlear aqueduct play any role in the perilymphatic pressure in normal individuals and patients with Ménière's disease. STUDY DESIGN: Prospective double-blind study. SETTING: The study was conducted at Hacettepe University Medical Faculty, a tertiary care center. PATIENTS: Forty patients with Ménière's disease with bilateral involvement, diagnosed by vertigo attacks, fluctuating hearing loss, tinnitus, fullness in the ear, and cochlear sensitivity constituted the patient group. Forty healthy individuals with no otolaryngologic symptoms constituted the control group. INTERVENTIONS: All individuals underwent SAC measurement in terms of equivalent volume in milliliters, based on two volume measurements. To measure the dimensions of the cochlear aqueduct, high-resolution computed tomography of the temporal bone in the axial plane was performed. RESULTS: There was no statistically significant difference in the width of the cochlear aqueduct between patients with Ménière's disease and normal subjects. When SAC measurements were also taken into account, there was no difference in cochlear aqueduct dimensions between individuals with normal and low SAC values in the two groups. CONCLUSION: The dimensions of cochlear aqueduct are not significantly different in Méniére's disease patients and normal individuals. Also, the cochlear aqueduct does not appear to play a significant role in normal and low SAC values in the two groups of individuals.

Perilymphatic pressure measurement in patients with Menière's disease.

The MMS-10 Tympanic Displacement Analyser is a new device for measuring perilymphatic pressure in humans. This instrument was used in 70 patients with Menière's disease (44 affected ears) and a group of 50 young normal hearing subjects. No significant differences in perilymphatic pressure measurements were found between the groups. Although measurement parameters showed large inter-individual variation in a subgroup of 25 patients, the intra-individual correlation in the subgroup was good. In patients with Meniere's disease no relationship was found between perilymphatic pressure, hearing thresholds, blood pressure, gender or age. There was no difference between unilaterally and bilaterally affected patients.

Persistent bilateral hearing loss after shunt placement for hydrocephalus. Case report.

Transient hearing decrease following loss of cerebrospinal fluid (CSF) has been reported in patients undergoing lumbar puncture, spinal anesthesia, myelography, and/or different neurosurgical interventions. The authors present the first well-documented case of a patient with persistent bilateral low-frequency sensorineural hearing loss after shunt placement for hydrocephalus and discuss the possible pathophysiological mechanisms including the role of the cochlear aqueduct. These findings challenge the opinion that hearing decreases after loss of CSF are always transient. The authors provide a suggestion for treatment.

Stress electrocochleography.

Electrocochleographic recordings after changes of middle-ear and intracranial pressure were studied in a group of otologically normal subjects and in patients with suspected Ménière's disease. Electrocochleography performed under these conditions was called stress electrocochleography. It was useful to distinguish among Ménière's disease, benign positional vertigo, and a round-window fistula. Changes of middle-ear pressure, whether positive or negative, always resulted in a rise of the SP/AP ratio. Raised intracranial pressure after Trendelenburg positioning showed fluctuations of the SP/AP ratio in both normal subjects and symptomatic patients. However, in normal subjects, a congruent pattern of these fluctuations was apparent, whereas symptomatic patients exhibited a discordant pattern. The discordant pattern, typical for Ménière's disease, showed an increase of the SP voltage, whereas the AP voltage decreased. In benign positional vertigo, the SP voltage decreased, and the AP voltage increased, once during Trendelenburg positioning and again at the end of the test when starting position was resumed. During raised intracranial pressure after the Queckenstedt maneuver, round-window fistulas showed an increase of the SP voltage, whereas the AP voltage decreased considerably. At our clinic, stress electrocochleography has become an important neurootological test in the differential diagnosis of Ménière's disease.

Perilymphatic pressure dynamics following posture change in patients with Menière's disease and in normal hearing subjects.

The hydrostatic pressure of the inner ear depends on the cerebrospinal fluid pressure through the cochlear aqueduct. The time-course of inner ear pressure change following rapid change in cerebrospinal fluid pressure is related to the aqueduct patency. In this study the patency of the cochlear aqueduct in 27 patients with Menière's disease (28 affected ears, 16 non-affected ears) and in 12 normal hearing subjects (18 control ears) was assessed non-invasively by means of the MMS-10 Tympanic Displacement Analyser. Following a rapid change in body position, changes in intracranial cerebrospinal fluid pressure were found to influence perilymphatic pressure within 1 min. No significant differences were found among affected ears, non-affected ears and control ears.

[Noninvasive determination of pressure relations of intracranial and intracochlear fluid spaces during the glycerol test in normal probands and patients with Menière's disease]. / Nicht invasive Bestimmung der Druckverhältnisse in den endokraniellen und intracochleären Flüssigketsräumen unter Durchführung des Glyceroltests bei Normalpersonen und Patienten mit Morbus Menière.

BACKGROUND: The cochlear aqueduct is a route for direct pressure transfer between intracranial and intracochlear fluids. In patients with Menière's disease, intracochlear pressure is presumably disturbed. The "Tympanic Membrane Displacement Analyser (TDA)" is a new system which provides a useful noninvasive method of detecting intracranial and intracochlear pressure changes. PATIENTS: In this study TDA measurements in combination with a glycerol test were performed in nine patients with Menière's disease and in seven normal persons. RESULTS: Before ingestion of glycerol, no significant difference in pressure was found between the two groups. After ingestion of glycerol a temporary decrease in intracochlear pressure was detected in both groups without any significant difference between the two groups. CONCLUSION: These results show that the combination of glycerol testing and TDA measurements does not seem to be helpful for the differential diagnosis of Menière's disease.

Perilymphatic fistula in teens and young adults: emphasis on preexisting sensorineural hearing loss.

Sudden hearing loss and new-onset vestibular disorders can be caused by perilymphatic fistulas (PLFs). In children, the existence of a severe or profound sensorineural hearing loss (SNHL) has been associated with a perilymphatic fistula when a sudden hearing loss or vestibular disturbance occurs. Likewise, at the other end of the age spectrum, several large series of PLFs in adulthood have been presented. This report focuses on a neglected age group, those in their teens and young adulthood. Twenty-three patients between the ages of 17 and 26 were studied who had a preexisting SNHL and had developed an additional hearing loss, a new vestibular disturbance, or both. An age-matched cohort of 21 patients with normal hearing was examined in relation to their medical history, diagnostic tests, and surgical outcome of a perilymphatic fistula repair. The findings of this report suggest that persons who have a preexisting SNHL are more likely to develop a perilymphatic fistula eventually than are persons with normal hearing.

Vein graft in stapes surgery.

Sealing the opening of the oval window during stapes surgery is essential; it prevents postoperative complications, such as perilymph fistula and sensorineural hearing loss. In this small series of 269 cases with otosclerosis, tympanosclerosis, and congenital ossicular abnormality, vein grafting was used to seal the opening of the footplate. Hearing improvement after surgery was acceptable, and none had total hearing loss or perilymphatic fistula. World literature from the last half of this century on grafting the oval window is reviewed. Absorbable gelatin sponge (Gelfoam) seems to be causing more complications, so its use is highly discouraged. Temporalis fascia, fat, and perivenous loose areolar tissue have been used by different authors at different times in footplate surgery. The opening created in the oval window during stapes surgery must not be left uncovered.

Fluorescein as an easy, low-cost, indirect, or reverse intraoperative marker to rule out perilymph versus local injection.

Clear fluid found in the dependent portions of the middle ear (round and oval windows) is generally assumed to be perilymph (PL). However, all clear fluid observed at middle ear exploration is not necessarily PL. PL should be distinguished from local injection. An accumulation of the local injection could be confused with perilymph fistula (PLF) diagnosis. There is no standard way of distinguishing perilymph from local injection, as both are clear, watery fluids. Fluorescein, tagged with a mixture of xylocaine and epinephrine (FLOTAX) was used as the local injection in 10 patients undergoing middle ear exploration for possible PLF.FLOTAX was injected into the vascular strip and ear canal skin in routine fashion. Transtympanic endoscopy and special Zeiss custom fluorescein filters were used to document any accumulation of fluid in the dependent portions of the middle ear and confirm whether any fluorescein (from the FLOTAX) was present. The middle ear was checked both before (endoscopically) and after raising the tympanomeatal flap. After the "local" injection, FLOTAX was observed to accumulate in dependent portions of the middle ear before raising the tympanomeatal flap in six of 10 ears. In the other four ears, FLOTAX slowly seeped into the middle ear cleft after the tympanomeatal flap was elevated and manipulated. Fluorescein can be used as an inexpensive, indirect intraoperative marker or "reverse test" for possible PLF. By eliminating a likely and common offender (local injection), any accumulation or reaccumulation of clear fluid that is not fluorescein tagged may more confidently be identified as possibly perilymph. The use of FLOTAX helps eliminate the confusion between the local injection and potential PLF. It does not in any way eliminate the possibility of other transudates from incisions, allergic reactions, or other manipulation of the tympanomeatal flap or middle ear mucosa.

Is perilymphatic pressure altered in tinnitus?

Tinnitus is characterized by the continuous or intermittent auditory perception of various sounds (buzzing, whistling, etc.) in the absence of any external stimulus. Perilymphatic hyperpressure is one of the numerous mechanisms which could hypothetically be involved in tinnitus generation. In the present experiment, perilymphatic pressure was measured indirectly using the tympanic membrane displacement technique. Twenty-five tinnitus patients were investigated at 10, 15 and 20 dB above the acoustic reflex threshold with ipsilateral stimulation. The variables Vi (inward tympanic displacement), Vm (mean tympanic displacement) and their variations according to stimulus level were compared between tinnitus sufferers and age-matched or hearing-matched controls. Tympanic displacement was measured in sitting and supine positions so as to evaluate cochlear aqueduct patency. No systemic changes in response occurred in tinnitus patients, except at a high stimulation level, perhaps due to hearing impairment.