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At least 289 records · Page 16Linked to original sources
PubMed1996

Middle ear anomalies induced by hypertriazene administration in the mouse.

The middle ear is derived from various embryonic tissues. Many experiments using teratogens have been performed, employing the difference of each tissue's sensitivity to the teratogen and the tissue's critical time of development. Triazene, a foliate metabolism antagonist, produced anomalies in fetuses that resembled those associated with thalidomide in humans, the so-called the first and second branchial syndrome. In our experiment, we administrated 3,3-dimethyl-1-phenyltriazene, an inductor of triazene, to pregnant mice at 7 to 14 days of gestation resulting in unique fetal anomalies. We examined the development of the stapes, stapedial artery, facial nerve, and oval window using an optical microscopic and three-dimensional reconstruction. Middle ear and facial nerve anomalies in mice depend on the gestation day when triazene is administrated. The stapedial artery, oval window, facial nerve (horizontal segment), stapes footplate, and styloid process are affected on the 9th to 11th administration day, the annular stapedialis on the 10th to 11th day, and the malleus and incus on the 9th to 11th day. The use of the Vox View/Mac, allowed us to create three-dimensional pictures from two-dimensional slides providing an improved understanding of the relationships between anatomical structures.

Animals↗
PubMed1983

Traumatic luxation of the stapes.

A case of traumatic middle and inner ear damage due to involuntary piercing of the tympanic membrane with a knitting needle is reported. The incudo-stapedial joint was dislocated and the intact stapes was depressed into the vestibule. Exploration of the middle ear, followed by extraction of the stapes, closure of the oval window with a vein graft and interposition of a prosthesis between the incus and oval window, improved the condition but did not restore inner ear function. A second case, of unclear etiology, is also presented. The indications, timing and technique of surgical intervention in cases of traumatic luxation of the stapes are briefly discussed.

Ear Ossicles↗
PubMed1995

[Classification of middle ear anomalies by a correspondence analysis method].

We studied on 70 cases of middle ear anomalies by a standard correspondence analysis method. The external meatus of these cases was open. We classified these 70 cases into the following four groups: type D: disruption between the long process of the incus and the movable oval window (54.3%), type F: immovable oval window with no disruption between the long process of the incus and the oval window (14.3%), type DF: anomalies with both immovable oval window and disruption between the long process of the incus and the oval window (18.6%), type O: anomalies of neither type D nor type F (12.9%). Half of these 70 cases had other miscellaneous anomalies, however, they did not affect the present results.

Ear, Middle↗
PubMed1996

[The clinical observations on 110 cases of adhesive otitis media].

The treatment of the adhesive otitis media (AOM) remains a challenge to the otologists. This paper analysed 110 cases of AOM (120 ears) collected during 25 years from 1967 to 1992. The clinical observation found that the lesions of AOM affected all parts of the middle ear, even the round and oval windows. There were various degrees of tympanic fibrous adhesions and atelectatic tympanum in these cases. After the tympanic adhesions were surgically separated and the lesions were removed, the silastic film or a slice of the homologous cartilages were put into the tympanum to prevent a new adhesion. It was showed that the silastic film was frequently enveloped in a capsule formed by the fibrous collagenous tissue and other extensive adhesions were existed around the capsule. But the cartilage slice caused the slighter pathological reactions. However, their hearing did not recovery to an available level. Therefore the further studies for the treatment of AOM are necessary.

Adolescent↗
PubMed1979

The double-membrane break syndrome in sudden hearing loss.

Some patients with sudden hearing loss actually have two membrane breaks, one at the oval or round window and one further inside the cochlea. One may heal spontaneously and the other not, or both, or neither. It is very likely impossible to detect this early from the threshold audiogram, because the intracochlear breaks allows endolymph and perilymph mixing which spreads over much of the anatomically normal clchlea causing diffuse loss of function. This theory is illustrated by three case histories.

Adult↗
PubMed1992

Positional audiometry in the diagnosis of perilymphatic fistula.

Fifty-eight cases with a presumptive clinical diagnosis of perilymphatic fistula (PLF) are described with the results of a positional audiometric test designed to detect the presence of air in the cochlea. All patients underwent tympanotomy and observations of the middle ear are recorded together with the results of treatment. A definite leak was found in 33 cases and none in 25, but grafting of the round and oval window was performed in all but 10 cases. Pure-tone audiometry was performed before and after a 30-minute period of positioning the patient horizontally with the affected ear uppermost. A change in audiometric thresholds was noted in the group where a presumptive diagnosis of PLF was made, including some of those not found to have leaks at operation. However these changes were not observed in the positional tests of a group of 22 patients with hearing losses attributable to other causes. Also, an abnormal air-bone gap was noted in the PLF group compared with the other group. Although the original two-frequency criteria of earlier studies applied to the positional test did not predict the operative findings (leak or no leak), new data on frequency specific changes are presented. It is possible that fistulas at the oval window may be associated with positional threshold change at 500 Hz, and those at the round window with changes at 8 kHz.

Audiometry, Pure-Tone↗
PubMedDate not supplied

Recurrent meningitis, congenital anacusis and Mondini anomaly.

Temporal bone polytomography should be performed in cases of recurrent meningitis, anacusis and vestibular areflexia. The finding of a Mondini-type anomaly is indicative of an oval window fistula. A further case is described, and scanning electron microscopic views of the defect in the stapedial footplate presented. Dysplasia of the otic capsule is considered to be the probable cause of this syndrome.

Deafness↗
PubMed1992

[Otosclerosis--diagnosis and therapy].

Otosclerosis (synonym: otospongiosis) is a focal or diffuse spongifying disease of the bony labyrinth. So far pathogenesis is unknown, some recent investigations assume a paramyxovirus infection. But there are no doubts about hereditary and genetic factors, females are twice often affected as males with a maximum incidence between 20 and 40 years. If the disease invades the oval window niche it causes fixation of the stapes with conducting hearing loss. In some cases otospongiosis is associated with and presumably causes cochlear degeneration alone with sensoneurale hearing impairment of varying degree. The surgical technique is now well developed and the operative treatment enables in over 90% a closure of the air-bone gap by using stapes pistons. The medical therapy in cases of sensoneural hearing loss with sodium fluoride is still controversially discussed.

Adult↗
PubMed1992

Facial canal dehiscence: histologic study and computer reconstruction.

The incidence, location, shape, and dimensions of dehiscences in the facial canal to the middle ear space were studied in 160 temporal bones obtained from 129 individuals 24 gestational weeks to 109 years of age at death by means of light microscopy and our computer reconstruction and measurement method. Dehiscences were observed in 95 of the 129 individuals (74%) and in 119 of the 160 bones (74%). The incidence was found to be quite high among fetuses and newborns, lowest in individuals in their twenties and then again quite high in the geriatric population (chi 2 test, chi 2 = 5.45 and 4.41, p < .05). The most frequent site of dehiscence was the oval window area, particularly in its posterior half (57% of all ears) on the inferior to inferomedial aspects of the canal; these dehiscences were clearly demonstrated in reconstructed images. The incidence of dehiscence in the area of the cochleariform process was 16%, and all these dehiscences were on the lateral to superolateral aspect of the canal. The second genu area and the mastoid portion were sites of dehiscence in 21% and 18%, respectively, of specimens; more than half of the dehiscences in the second genu area and mastoid portion were on the lateral to anterolateral and posterior aspects of the facial canal, respectively. The shape of the dehiscence tended to be oval in the oval window area, but rather irregular in the other areas. The dehiscences 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. The proximity of these dehiscences to the field of otologic surgery is stressed.

Adolescent↗
PubMed1993

Spontaneous perilymphatic fistula: electrophysiologic findings in animals and man.

The case against the occurrence of spontaneous perilymphatic fistulas is presented. Electrophysiologic findings both in animals and in man suggest that small holes in either the round or oval window are not associated with any significant hearing loss. Removal of perilymph may cause some changes in the electrocochleogram that can be reversed when the perilymph is replaced. Tympanotomy surgery, especially when performed with the injection of local anesthetic solutions may result in transudates in the middle ear that are difficult to differentiate from perilymph leaking out from the inner ear. Perilymphatic fistulas were excluded by performing a posterior myringotomy under general anesthesia in 162 congenitally deaf ears. If fluid was present it was suctioned, and if no change occurred on the intraoperative electrocochleogram, it was concluded that no fistula existed. Based on the electrophysiologic findings and the clinical observations in over 240 ears, it was concluded that spontaneous perilymphatic fistulas do not exist. The author accepts that perilymphatic fistulas occur after surgery, especially after stapedectomy, and that they can occur after head injury or barotrauma. However, these should heal readily; persistent or intermittent fistulas are an otologic rarity.

Adult↗
PubMed1991

Ablation of otolithic organs with argon laser.

Utricular maculae of guinea pigs were irradiated by argon laser through the oval window without touching the perilymph. The stapes was replaced in the oval window after irradiation. The inner ear was studied morphologically and physiologically. Argon laser beam caused detachment of the sensory epithelium from the basement membrane of the utricular macula. The lesion was round and localized at the site of irradiation. The epithelium changed to a layer of cuboidal cells after 2 to 3 weeks at the irradiated spot. Degeneration of the epithelium gradually spread to the periphery, and total loss of sensory epithelium was observed 10 weeks after irradiation. Hearing was preserved, and caloric test showed normal response.

Acoustic Maculae↗
PubMed2000

[Revision surgery of otosclerosis: a review of 26 cases].

OBJECTIVES: The aim of this study was to identify causes of primary stapedectomy failures and to evaluate hearing results in revision stapes surgery. MATERIAL AND METHODS: We retrospectively reviewed a series of 26 revision stapedectomies. Patient characteristics, preoperative findings, causes of failure and complication of primary stapedectomy and postoperative hearing results were noted. RESULTS: Conductive hearing loss was the most common reason for revision surgery (77 %). Leading causes of stapedectomy failure included prosthesis malfunction (42 %), fibrous adhesions (37,5 %), incus erosion (12,5 %) and otosclerotic regrowth (12,5 %). When revision was indicated because of cochleo-vestibular complication, middle ear exploration revealed 3 problems: oval window granuloma or excessively long prosthesis or perilymphatic fistula. In this series, postoperative air-bone gap was closed to less than 10 dB in 57 % of cases, to less than 20 dB in 71 % of cases and we did not observed any sensorineural hearing loss. CONCLUSION: The results of this series are comparable with previously published studies. Revision stapes surgery is not as successful as primary stapedectomy, but the risk of sensorineural hearing loss does not appear to be higher than in primary surgery. Revision surgery is a challenging problem that must be performed by an experienced surgeon.

Adult↗