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At least 91 records · Page 5Linked to original sources
PubMed1989

Spontaneous perilymphatic fistula in children.

Treatment of fistulae in children should be targeted at four different problem areas. The surgical intervention of these fistulae is most efficacious in controlling recurrent meningitis, which has not been discussed in this paper, and in the controlling of vestibular symptoms. Whether or not it will stop the progression of hearing loss or restore hearing is not known in a group of patients. It has been documented in this and other reports that the closure of the fistula will in specific cases appear to be associated in time with a stopping of the progression of the hearing loss and is associated also in time with the restoration of hearing function. Various factors must be considered in developing criteria for intervention. A decision to explore the ear should be based on history, audiometric change, vestibular testing including a fistula test, and malformation of bony labyrinth.

Adolescent↗
PubMed1999

The leaking labyrinthine lesion resulting from direct force through the auditory canal: report of five cases.

The leaking labyrinthine lesion is treated by conservative methods or surgical procedures. With respect to the stapes, the surgical treatment is controversial. Five cases of middle ear injuries accompanying oval window rupture are reported herein. In each case, direct force through the auditory canal damaged not only the ossicular chain but also the oval window. Initial symptoms were sudden hearing loss with significant conductive disturbance and various degrees of unsteadiness. Spontaneous horizontal nystagmus directed toward the uninvolved ear was observed in each case. Tympanic cavities were promptly explored under general anesthesia and oval window injuries were confirmed. In each case, the damaged stapes was temporally removed from the oval window. Perilymphatic leakage was recognized in each case. Two patients had subluxation of the stapes with a paucity leakage. Three had complete luxation of the stapes with a relatively huge oval window fistula. Disrupted oval windows were repaired with temporalis muscle fascial grafts that were inserted under the middle ear mucosae surrounding the oval windows. The stapes were replaced in the repaired oval windows, and the ossicular chains were reconstructed without artificial grafts. Vestibular dysfunctions disappeared within 7 days, and satisfactory audiologic results were obtained in each case.

Adult↗
PubMed1993

Impedance transfer: acoustic impedance of the annular ligament and stapedial tendon reconstruction in otosclerosis surgery.

The resistance rebuilt around the lower tip of the piston must be the same as that created by the annular ligament of the stapes footplate. Otherwise, the threshold at which an acoustic or barotrauma is able to damage the membranes and hair cells of the inner ear will be lowered. The elasticity reestablished around the lower tip of the piston plays a part in the quality and quantity of hearing for the low frequencies up to 3 kHz. To protect the ear against acoustic traumas, an attempt to rebuild the stapedial reflex is proposed.

Acoustic Impedance Tests↗
PubMed2005

[Surgical experience by 95 malformed stampedes and otosclerosis].

OBJECTIVE: To investigate the effect of stapes surgery for conductive hearing loss with intact tympanic membrane and eustachian tube. METHOD: Stapes surgery data of 95 conductive hearing loss patients, which with intact tympanic membrane and eustachian tube, was retrospective analyzed,and the surgical effect of otosclerosis, middle ear deformities and external canal stenosis was summarized. RESULT: Postoperative (4 weeks after the surgery) pure tone threshold test demonstrated that the effect of Vestibulotomy was better than incus-footplate connection (incus and footplate is connected by a cortical bone ) ( P <0.05). The surgery to the patients with external canal stenosis was better than those with otosclerosis or middle ear deformities ( P <0.05). There was no statistic significance between physiological stapedectomy and Vestibulotomy. The follow-up of 1-3 years showed that the pure tone threshold of 8 out of 14 cases reverted to the preoperative level, while the hearing improvement in the other cases still remained. CONCLUSION: Stapes surgery to the patients with stapes-oval window deformities is of significance compared with those with otosclerosis.

Adolescent↗
PubMed1988

ECoG results in perilymphatic fistula: clinical and experimental studies.

Patients with perilymphatic fistula have been described as having symptoms similar to Meniere's disease and endolymphatic hydrops. Direct clinical or experimental evidence linking the two inner ear disorders has been lacking. An enhancement of the summating potential observed with electrocochleography suggests a diagnosis of ELH in both of these inner ear disorders. In this study, ECoG results of 27 patients with surgically confirmed PLF are reported. Fourteen patients with surgically confirmed spontaneous PLF had abnormal ECoG. Six of these 14 patients had normal hearing. The ECoG changes in patients with Meniere's disease and those with surgically confirmed PLF are identical, indicating the underlying pathologic change in both is hydrops. But there is no specific diagnostic abnormality on ECoG that differentiates these two inner ear disorders. Also, an experimental model of PLF was developed and studied in guinea pigs. "Inactive" PLF is defined as "an opening was made into the cochlea, but if no perilymph moved out through the fistula, it was defined as inactive" An "active" PLF occurs when perilymph actually moves from the inner ear out to the middle ear. ECoGs were recorded before and after creation of an "active" PLF. ECoG abnormalities were seen in "active" PLF and correlated with histologic data demonstrating ELH. An abnormally enhanced summating potential was demonstrated after active removal of perilymph through the experimentally created fistula. Cochlear duct histology showed hydropic distention of Reissner's membrane in the experimental ears and no changes in the membranous labyrinths of the unoperated, control ears.(ABSTRACT TRUNCATED AT 250 WORDS)

Action Potentials↗
PubMed1996

Identification of photoacoustic transients during pulsed laser ablation of the human temporal bone: an experimental model.

Laser ablation of hard tissues during neurotologic operations has been accomplished with continuous-wave (CW) lasers in the visible and midinfrared spectrum. The mechanism of ablation at these wavelengths is secondary to photothermal-induced tissue destruction. As a result, significant thermal damage to surrounding tissue may occur. Pulsed ultraviolet (UV) lasers have been suggested as an alternative to the argon, KTP-532, and CO2 lasers currently used in clinical practice. The pulse length of Excimer lasers are considerably shorter than the thermal diffusion time of bone tissue, and as a consequence thermal injury is minimal. This makes pulsed lasers an attractive tool for tissue ablation in the ear: in essence a "cold knife." However, the short pulse width of Excimer lasers (typically 10-150 ns) can create large thermoelastic stresses in the ablation specimen. This study identifies the presence of these photoacoustic waves during the Excimer laser treatment of the cadaveric human temporal bone. A XeCl (lambda = 308 nm, tau p = 12 ns) excimer laser was used to ablate hard tissue surrounding the oval window and facial ridge with energies of 75, 45, 25, and 12 mJ/pulse. Spot size was estimated to be 0.5 mm2. Custom high-frequency polyvinyldifluoride (PVDF) piezoelectric film transducers were fabricated and attached to the promontory, round window niche, and facial ridges. The signals were amplified using a low-noise preamplifier and recorded on a digitizing oscilloscope. Photoacoustic waves were clearly identified. Notably, large acoustic waves were measured on the promontory and on both sides of the facial ridge. The implications and clinical relevance of these findings is discussed and compared to findings obtained from a model system.

Acoustics↗
PubMedDate not supplied

Perilymphatic fistula: a histopathologic study.

Over the last two decades, clinical criteria for perilymphatic fistulae have been defined to the extent that differentiation can be made between such fistulae and other balance-affecting disorders such as Meniere's syndrome. On the assumption that the specimens in the temporal bone bank of the University of Chicago Medical School that had been obtained from patients having vertigo, hearing loss, or both, before those clinical criteria were so defined might have been classified incorrectly, we proposed a retrospective histopathologic study, with prediction of two independent variables: a clinical history and physical findings consistent with the diagnosis of perilymphatic fistula and communication between the vestibule and the middle ear adjacent to or via the fissula ante fenestram. Eleven pairs of temporal bones with the histologic diagnosis of idiopathic labyrinthine hydrops were evaluated before the clinical histories relevant to those specimens were reviewed. In one specimen, a communication between the vestibule and the middle ear space was identified. In none of the other specimens was there a similar communication. As this study continued, significance was given to the histologic details of the communication between the middle ear and posterior canal ampulla. The temporal bones without these communications did not have clinical histories consistent with the diagnosis of perilymphatic fistula.

Aged↗
PubMed1981

Failures in surgery for stapedial otosclerosis.

The causes for failure in surgery for stapedial otosclerosis are many. Most of these occur in the early postoperative period. Failures occurring later are due to either a breakdown of the reconstructed transformer system or to a labyrinthitis due to failure of the vestibular seal. The role of cochlear otospongiosis in producing late failures has not been sufficiently emphasized. This clinical review of 105 surgical failures examined consecutively during the years of 1975 through 1979 will demonstrate the importance of cochlear otospongiosis in this consideration. The fate of the unoperated-on ear in unilateral surgical failures will be demonstrated. Control of the progressive sensorineural hearing loss in these instances can be gained by the use of sodium fluoride therapy.

Adolescent↗
PubMed1991

Repair of a cerebrospinal fluid perilymph fistula primarily through the middle ear and secondarily by occluding the cochlear aqueduct.

A 35-year-old man had a 5-year history of fluctuating hearing loss in his only hearing ear. History and diagnostic tests indicated a perilymph fistula, a diagnosis subsequently confirmed by exploration. Primary and secondary repairs temporarily ameliorated symptoms. A spinal fluid to middle ear fluid pathway was identified by radioactive tracer. A patent cochlear aqueduct indicated on computed tomography scan was found and repaired through a posterior cranial fossa approach. Hearing was preserved, remaining relatively stable during the 2-year follow-up period.

Adult↗
PubMed1992

Survival and evolution of vein grafts in otosclerosis surgery: structural and ultrastructural evidence.

The annular ligament of the stapes footplate measures 0.2 mm2 and contains elastic fibers that restrict perilymphatic movement to a molecular level. This resistance of the annular ligament prevents excessive movement of labyrinthine fluids that are potentially hazardous to the membranous and cellular structures of the inner ear. However, if the resistance of the annular ligament is overcome, then inner ear damage can occur. The vein graft, as used in our technique for otosclerosis surgery, occupies a space of 0.2 mm2 between the edge of the stapedotomy hole and the piston and has nearly the same compliance and resistance as the annular ligament of the stapes footplate. The vein graft becomes integrated with the middle-ear mucosa. It develops a rich and active blood supply and the smooth muscle cells and elastic fibers remain, although the latter show some modification of ultrastructural pattern. The graft becomes overlaid by the middle-ear epithelium. Even samples of vein graft that have been present for many years retain surviving elastic fibers, including those that have become fibrotic. In time, the number of elastic fibers increases as a result of the activity of fibroblasts, which build a poorly colored collagen.

Adult↗
PubMed1988

[Electrical stimulation of the fenestra ovale. Perspectives].

Amongst the various sites for stimulation of the internal ear, in monocanal-extra-cochlear system, the fenestra ovale has virtually never been used. The authors suggest a cup-shaped electrode placed at the end of an incudo-vestibular prosthesis, such as a teflon piston, after stapedectomy and interposition of connective tissue. The immediate advantage of such a method is the fixation of the electrode. Tolerance is excellent and electrical impedance remained stable at very satisfactory levels. The future perspective appearing most promising is based upon simultaneous use of electrical and acoustic stimulation.

Acoustic Stimulation↗
PubMed1985

[Perilymph fistulas--symptoms and indications for tympanoscopy].

In the last two years thirteen cases of perilymph fistula were treated by tympanoscopy and covering with connective tissue. Recovery of hearing was not observed in 4 totally deaf ears, but improvement was recorded in each of 9 cases with impaired hearing. Vertigo disappeared in 10 of 11 cases without any correlation with the degree of hearing loss. We perform tympanoscopy in suspected perilymph fistula, because prognosis is uncertain, spontaneous recovery with remaining defects may induce ménièriform syndrome, and pathway of infection should be closed. The diagnosis of a perilymph fistula must be solidified in cases of sudden deafness with vertigo, sudden hearing loss changing to the worse during medical treatment, sudden hearing loss without recovery during medical treatment, sudden hearing loss and subsequent onset of vertigo.

Adult↗
PubMed1989

Perilymphatic fistulas in children: rationale for therapy.

We report 26 consecutive patients (32 ears) who were identified in a 2 year period (July 1, 1985-June 30, 1987) with unexplained sudden, fluctuating, or progressive sensorineural hearing loss (SNHL). All patients underwent an exploratory tympanotomy and a perilymphatic fistula was identified in 13 patients (14 ears). The mean change of 14 +/- 27 dB in speech reception threshold before and after surgery was significant at p = 0.08 among children with fistula and ranged from -30 to 80 dB. In children with sudden, progressive or fluctuating SNHL and multiple sensory deficits, including blindness or contralateral SNHL, or prior head trauma, prompt surgical exploration is mandatory. Additionally, the aggressive management of otitis media with effusion is essential in such patients to minimize fluctuations in hearing caused by superimposed conductive hearing loss. Caution must be exercised to separate fluctuating hearing loss from fluctuations in audiologic testing.

Adolescent↗
PubMed1998

Involvement of round and oval windows in the vestibular response to pressure changes in the middle ear of guinea pigs.

Changes in ambient pressure can elicit the vertigo and bodily disequilibrium known clinically as alternobaric vertigo. Our previous studies showed that changes in middle ear pressure altered the activity of the primary vestibular neuron, and the finding suggests that the pressure-induced vestibular response causes alternobaric vertigo. To investigate the roles played by the round window (RW) and the oval window (OW) in the vestibular response induced by pressure, we measured the change in perilymphatic pressure and the firing rates of primary vestibular neurons after the application of positive or negative pressure to the middle ear. We found an increase in the pressure-induced vestibular response in the group with a closed OW, and a decrease in the group with a closed RW. Measurements showed that the amplitude of the change in perilymphatic pressure in the group with a closed OW did not differ from that in the control group, whereas the amplitude of the perilymphatic pressure change in the group with a closed RW was significantly reduced. A discrepancy between the number of neurons responding and the amplitude of the perilymphatic pressure change in the closed OW group suggests that the vestibular response induced by the change in middle ear pressure was not related solely to the magnitude of the pressure change in the inner ear, but also involved the oval and round windows.

Animals↗
PubMed1988

Surgical dimensions of the facial recess in adults and children.

The facial recess approach permits surgical access to the round window area. This route is used in patients who are undergoing cochlear implantation. To evaluate the feasibility of this procedure in children as compared with adults, serial sections of temporal bones were used to measure the surgical dimensions of the facial recess. No statistically significant differences in the dimensions of the facial recess or the extended facial recess approaches were found between children and adults. The relationship of the facial and chorda tympani nerves to the annular plane exhibited no change with postnatal growth. These structures translate posteriorly and laterally toward the annular plane as they descend within the temporal bone. Therefore, the facial recess approach represents no greater hazard in a child than in an adult.

Adult↗
PubMed1991

Surgical management of perilymph fistulas. A new technique.

A wide range of recurrence rates (21% to 47%) for perilymph fistula repairs have been reported in the otology literature. An improved surgical technique developed at the Portland (Ore) Good Samaritan Hospital and Medical Center Neurotology Department was used to repair perilymph fistulas in 58 patients from October 1986 to October 1988. Our recurrence rate was reduced from 27% in a 1982-1985 study to 8% in our study. At 1 year postoperatively, improvements in disequillibrium, dizziness, and vertigo were comparable with results of older surgical techniques. Functional outcomes were also good: 83% of patients returned to normal activities of daily living, and 71% also returned to school or resumed gainful employment outside the home.

Adolescent↗
PubMed1990

Cholesteatoma in the oval window niche.

The histopathological changes in the oval window niche into which a cholesteatoma is spreading are described in 14 temporal bones. Extension of the matrix into the niche was found commonly. In some cases the matrix passed from the facial canal to the promontory but failed to reach the niche. The perimatrix of the cholesteatoma was composed of inflamed and vascularized granulation tissue or fibrocystic tissue. A matrix covering the walls of the niche and the footplate of the stapes or the oval window was rarely found. It was surrounded by a thin layer of non-inflamed fibrous or fibrocystic tissue which covered the niche. Bone destruction of the superstructures of the stapes was observed in 12 of the 14 cases examined. The footplate of the stapes was partially or totally destroyed in 4 cases. Bone destruction of the tympanic portion of the facial canal adjacent to the oval window niche was present in all cases. Our present studies further suggest that surgical removal of a cholesteatoma from the niche may be difficult, even when done very carefully.

Cholesteatoma↗