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At least 73 records · Page 4Linked to original sources
PubMed2003

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.

Acoustic Impedance Tests↗
PubMed1980

Vestibular fenestration and stapedioplasty in congenital stapes and vestibular window abnormality.

In this paper the results of vestibular fenestration and stapedioplasty in cases of congenital stapes deformity and vestibular window abnormality are presented. The problems in the surgical reconstruction of the middle ear transmission system, especially the importance of the areal ratio between the tympanic membrane and the vestibular window and the ossicular lever action, are discussed. The following conclusions were reached: 1. The area of the new vestibular window should be greater than 2.0 x 1.0 mm, i.e., one third of normal. 2. Hearing gain was about 1.5 times better after incus-stapedioplasty than after malleus-stapedioplasty. It is recommended that an effort be made to adopt incus stapedioplasty whenever possible.

Adolescent↗
PubMed2004

Fallopian canal dehiscences: a survey of clinical and anatomical findings.

This survey investigates fallopian canal dehiscences in order to assess the risk of encountering an unprotected facial nerve during routine ear surgery. In a prospective non-randomized study, the intraoperative appearance of the facial canal in 357 routine ear operations was compared with 300 temporal bone specimens from 150 autopsies. Intraoperatively, a dehiscence was detected in 6.4% (23/357) of the operations, most frequently at the oval niche region (16/23 cases). The incidence increased with the number of operations (P<0.0002). Cholesteatoma surgery had the highest relative risk (RR 4.6) of exposing an unprotected facial nerve. Postoperatively, no persistent facial paralysis was observed. In four of five cases with a transient facial palsy due to local anesthetics, a bony dehiscence could be found. The anatomical study revealed fallopian canal dehiscences in 29.3% (44/150) of the autopsies. One-third (15/44) of the individuals affected displayed bilateral findings, thus resulting in 19.7% (59/300) of temporal bones affected. A total of 17/59 bones showed microdehiscences, and most (55/59) were located at the oval niche. The actual prevalence of fallopian canal dehiscences is significantly higher than intraoperative findings suggest. The oval niche is the most affected region. High-resolution computed tomography is of diagnostic value only in selected cases. Facial paralysis following local anesthesia is the most significant clinical sign. Vigilance in acute facial palsy after local anesthetics and in cholesteatoma surgery and adequate intraoperative exposure help to prevent iatrogenic injury of the uncovered nerve. In unclear cases, nerve monitoring can facilitate a safe outcome.

Adolescent↗
PubMed1982

Meningitis and congenital fistula of the internal ear.

Congenital CSF otorrhea is seldom the cause of meningitis but has to be looked for especially if associated with a dead ear or with recurrent meningitis. Polytomograms of the mastoids are essential to rule out any abnormality of the internal ear. Three patients with a congenital CSF otorrhea and associated meningitis are reviewed. They all presented a Mondini type of dysplasia and had an oval window fistula. They were treated successfully with fascia and muscle obliteration of the vestibule.

Adolescent↗
PubMed2004

The topographical anatomy of the round window and related structures for the purpose of cochlear implant surgery.

The treatment of total deafness using a cochlear implant has now become a routine medical procedure. The tendency to expand the audiological indications for cochlear stimulation and to preserve the remnants of hearing has brought new problems. The authors have studied the topographical anatomy of the internal structures of the ear in the area where cochleostomy is usually performed and an implant electrode inserted. Ten human temporal bones were obtained from cadavers and prepared in a formalin stain. After dissection of the bone in the area of round and oval windows, the following diameters were measured using a microscope with a scale: the transverse diameters of the cochlear and vestibular scalae at the level of the centre of the round window and 0.5 mm anteriorly to the round window, the distance between the windows and the distances from the end of the spiral lamina to the centre of the round window and to its anterior margin. The width of the cochlear scala at the level of the round window was 1.23 mm, and 0.5 mm anteriorly to the round window membrane it was 1.24 mm. The corresponding diameters for the vestibular scala are 1.34 and 1.27 mm. The distances from the end of the spiral lamina to the centre of the round window and to its anterior margin are 1.26 and 2.06 respectively. The authors noted that the two methods of electrode insertion show a difference of 2 mm in the length of the stimulated spiral lamina. The average total length of the unstimulated lamina is 2.06 and 4.06 in the two situations respectively.

Cochlear Implantation↗
PubMed1993

Association of spontaneous anterior fossa CSF rhinorrhea and congenital perilymphatic fistula in a patient with recurrent meningitis.

A case of recurrent meningitis associated with spontaneous cerebrospinal fluid (CSF) rhinorrhea and left sensorineural hearing loss in a 4-year-old boy was found to be due to simultaneous congenital defects. High resolution CT examination clearly showed an anterior fossa defect and an inner ear malformation, including demineralization in the region of the footplate of the stapes, and thus provided clear guidance for the surgeon.

Cerebrospinal Fluid Rhinorrhea↗
PubMed1991

Stapes surgery: complications and airway infection.

From a group of 1,111 patients who had stapedectomy or stapedotomy performed in a 10-year period, a thorough investigation was made of 11 patients who had a total hearing loss and 8 patients who developed a partial sensorineural hearing loss after operation. The data obtained indicate that postoperative infection with influenza virus may be responsible for unexpected complications following stapedectomy. A close relation was found between the appearance of complications and periods of epidemics of influenza.

Adolescent↗
PubMedDate not supplied

The Robinson stapes prosthesis: a 15-year study.

A report on the stapedectomy procedure using the Robinson stainless steel stapes prosthesis over a 15-year period is presented in a study of 3,200 cases. Short-term results, long-term results, failures, and delayed complications are statistically analyzed. This implant is presently the most frequently used prefabricated stapes prosthesis in the country, and each year more otologic surgeons are adopting this surgical technique.

Adolescent↗
PubMed2004

[The cartilage guide: a solution for anchoring a columella-prosthesis on footplate].

BACKGROUND: A torp (columella-prosthesis) is the typical ossicular reconstruction in cases of a destroyed stapedial arch. Yet, many unsatisfactory hearing results are due to the lack of a stable, reliable anchoring of the base of the prosthesis on the footplate. Some solutions have been postulated, amongst them the perforation of the footplate with a tiny spike at the lower end of the prosthesis, which, however, many otosurgeons regard as too dangerous for the inner ear. Specially designed silicone sheets cannot guarantee a permanent guide of the columella. METHODS: From our good experience with cartilage in different reconstruction procedures, we therefore developed a cartilage guide for the oval window niche. An oval 2,5 x 3,5 mm cartilage with a central hole is cut out of a thin (0,2 - 0,3 mm) cartilage plate with a help of a cartilage punch, which we had designed in collaboration with Heinz Kurz manufacture. The cartilage is placed into the oval niche and its hole guides the prosthesis onto the centre of the footplate. RESULTS: Temporal bone experiments demonstrated a reliable sound transport through this guide. Revision surgery revealed a stable ingrowth of the cartilage plate into the oval niche, its perforation securely guiding the prosthesis similar to a piston on to the footplate. The first short time hearing results (max. 1 year) in 22 patients confirmed the acoustic quality of this stabilisation of a columella on the footplate as compared to a matched control group. CONCLUSIONS: The stabilization of the columella with a cartilage-guide might solve one of the many problems with unsatisfactory hearing results after the reconstruction of a completely destroyed ossicular chain.

Adolescent↗
PubMed1995

Posterior canal-activated excitatory vestibuloocular relay neurons participate in the vestibulocortical pathways in cats.

We have previously reported that axon collaterals of posterior canal-activated excitatory vestibular (PC) neurons project to the contralateral oculomotor nucleus, and rostrally to the thalamus. To elucidate the vestibulothalamocortical pathways we investigated the synaptic connections of the PC neurons with the thalamic neurons by post-spike averaging of compound potentials triggered by spikes of the PC neuron in anesthetized cats. The averaged field potential evoked in the ventrobasal complex (VBC) revealed a spike followed by a negative wave. Latencies of the wave ranged from 0.8 to 1.5 ms. Next, we examined the location and axonal projection of 36 thalamic neurons which were activated by nose-up head rotation and by contralateral labyrinth stimulation. Most of them were located in the VBC and some in the medial geniculate body. Thirteen of the 36 neurons were antidromically activated from the anterior suprasylvian sulcus or postcruciate dimple of the cortex. These results suggest that the PC neurons participate, at least in part, in the vestibulocortical pathways contributing to spatial orientation.

Animals↗
PubMed1993

Computer-aided three-dimensional reconstruction and measurement of facial canal dehiscence.

Location, shape and dimensions of the dehiscence in the facial canal to the middle ear space were studied in 20 temporal bones obtained from 19 individuals aged 1 day to 72 years at death by using our computer reconstruction and measurement method. The most frequent site of dehiscence was the oval window area (70%), particularly in its posterior half and on the inferior to inferomedial aspect of the canal. The shape of the dehiscence tended to be oval in the oval window area, but rather irregular in the other areas. The dehiscence ranged from 0.4 to 2.64 mm in length, from 0.12 to 1.59 mm in width, and from 0.03 to 1.87 mm2 in surface area. Proximity of these dehiscences to the field of otological surgery is stressed.

Computer Graphics↗
PubMed1987

Perilymph fistula: an important cause of deafness and dizziness in children.

This study underscores the importance of considering a perilymph fistula, an abnormal communication between the inner and middle ear, in any child with a progressive sensorineural hearing loss. A concomitant complaint of intermittent dizziness or observed spells of imbalance (56%) is another indication of the disease. Six of 16 patients (37.5%) with proven fistulas were less than 2 years of age at the onset of symptoms. Unless the fistula is identified and repaired by grafting, the ear may become totally deaf. This would be disastrous in the presence of bilateral fistulas, which occur commonly in children (56% of patients had symptoms of bilateral disease). Our experience in recognizing and treating fistulas and thereby saving and restoring hearing is described.

Adolescent↗
PubMed1976

Symposium: Congenital anomalies of the middle ear. IV. Management of profuse perilymph leak.

Profuse perilymph leak during an otological operation can be controlled by inserting an epidural teflon cannula into the lumbar subarachnoid space and draining away the excess spinal fluid. After about 100 cc is removed the perilymph leak stops, and the oval window can be sealed with a living seal, such as vein, and the operation completed. The catheter is left in the subarachnoid space for about four days, with a bottle on the distal end positioned to remove no more than 150 cc of spinal fluid per day. Results with two patients in which this maneuver was used to control profuse perilymph leak are reported.

Catheterization↗
PubMedDate not supplied

The vestibular nerve: its course to the anterior and lateral ampullae.

The course of the ampullary nerve to the anterior and lateral ampullae was studied using 25 human temporal bones. Sudan Black B staining was applied to decalcified temporal bones in order to stain nerve fibers. After removing the external and middle ear, each temporal bone was divided into four blocks by three parallel planes, making an angle of 45 degrees to the long axis of the stapes footplate or a line along the stapedial tendon. Two planes were in contact with the anterior and posterior margin of the oval window, respectively. The third plane passed through the capitulum of the stapes. Distances from the upper margin of the oval window, to the distal and proximal part of the ampullary nerve, to the facial nerve, and to the utricular macula were measured in the third plane. The thickness of the thinnest part of the wall of the facial canal facing the stapes was also measured. A new surgical approach to the ampullary nerve is discussed.

Aged↗
PubMed2002

Photoacoustic effects of carbon dioxide lasers in stapes surgery: quantification in a temporal bone model.

HYPOTHESIS: The use of the CO2 laser in stapes surgery creates sound waves that could damage hearing. BACKGROUND The application of a laser to any medium has absorption, reflection, and thermal effects. To date, the majority of research on the safety of CO2 laser stapedotomy has focused on the thermal effects of the laser alone. Because of the properties of the CO2 laser, its absorption also presents some risk to the inner ear. This absorbed energy can be converted to photoacoustic or photochemical effects. The goal of this paper is to measure these photoacoustic effects (sounds) produced by the CO2 laser. METHODS: Using a variety of settings, a Sharplan 150 XJ Laser and a Contour model Erbium:YAG laser were applied to the oval window of human temporal bones. Perilymph was simulated by fixing the temporal bone in a normal saline bath. Photoacoustic waves were measured by a hydrophone 2 mm beneath the oval window. Measurements were made with and without a simulated tissue seal over the window. RESULTS: No detectable sounds were created below 4 watts (continuous mode) or 60 mJ (superpulse mode). Above those settings, intensities of 90 dB sound pressure level and higher were detected when the laser was applied directly to the perilymph. With the tissue seal in place, no detectable sounds were identified. The accuracy of this model was confirmed by comparing these results with previously published results using the Erbium:YAG laser. CONCLUSIONS: Below 4 watts in continuous wave mode and below 60 mJ in superpulse mode, any sound generated by the laser is small. Above these thresholds, however, impact sounds are produced that could result in threshold shifts with repeated applications.

Humans↗
PubMed1991

Perilymph fistula--a diagnostic dilemma.

A retrospective series is presented of 51 cases operated on for suspected perilymph fistula. In 26 ears a fistula was identified at surgery. A positive fistula test was found to strongly indicate a perilymph fistula but was more often negative than positive in surgically demonstrated fistula ears. Other vestibular tests were found to be of little value in the pre-operative diagnosis. Ears with a surgically demonstrated fistula and sensorineural hearing loss had either flat or downward-sloping audiograms. Difficulties in diagnosing a perilymph fistula at tympanotomy are discussed. At follow-up, vestibular symptoms were found to be eliminated or improved in 96 per cent of cases with surgically demonstrated fistulae and in 68 per cent of cases in which no fistula was detected at tympanotomy but hearing improved significantly in only one ear (4 per cent) of the former group and in five ears (20 per cent) of the latter group.

Adolescent↗