Morphogenesis and teratogenesis of the middle ear in animals.
Explore the source record for details and available documents.
Abnormalities, Drug-Induced↗
SEARCH · PubMed Health
Results for “Oval Window, Ear”
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Oval and round window membrane changes in otitis media in the human. An ultrastructural study.
An ultrastructural study of oval and round window changes in otitis media in humans was done. Ten cases were evaluated. In this first ultrastructural study of oval and round windows in otitis media, done at different stages of the disease, the round window membrane changes were similar to those of the mucoperiostium. Morphologic evidence suggests that the round window membrane layers participate in absorption and secretion of substances to and from the inner ear, such that the entire membrane could play a role in a middle and inner ear "defense system." Although the middle ear side of the footplate of the stapes had histopathological changes, the vestibular side remained essentially unchanged.
Adult↗
[About rupture and lesion of the labyrinthine windows (author's transl)].
After the extensive discussion of the last published literature on the different possibilities of a lesion of the labyrinthine windows, four own cases are discussed. In case of a typical anamnesis of single patients with sudden deafness after sudden exertion or trauma prior to onset the surgical exploration is recommended. It is concluded that spontaneous labyrinthine window ruptures must be added to the etiologic factors in sudden hearing loss.
Adult↗
Oval and round window changes in otitis media. Potential pathways between middle and inner ear.
A longitudinal sequential study of oval and round window changes in otitis media in an experimental animal (cat) using Eustachian tube obstruction was done. Thirty-two animals were used. In this first sequential study of the oval and round windows in otitis media, the continuum of round window membrane changes from 1 day to 6 months after obstruction revealed changes to be gradual and similar to those of the mucoperiostium. These changes are suitable for changes in permeability and suggest that this membrane is a very likely pathway from the middle to the inner ear. Bony fistulas were not observed and the oval window remained essentially unchanged in time, thus they were not considered routes into the inner ear. Other possible routes are discussed.
Animals↗
An empirical bound on the compressibility of the cochlea.
Effects of a possible inner-ear compressibility on middle-ear transfer functions are explored and a small upper bound on the magnitude of that compressibility established. Consequently. the traditional two-port representation of middle-ear mechanics remains valid to within a few percent. If the compressibility of the cochlea is small but finite, a simple phenomenological model of that compressibility correctly predicts hearing thresholds in the "middleless" ear at low frequencies. Experiments to establish the value of cochlear compressibility and to explore further its possible contributions to residual hearing in patients with missing or disarticulated middle-ear ossicles are suggested.
Animals↗
Symposium: Congenital anomalies of the middle ear. III. Congenital anomalies of the middle ear.
Congenital anomalies of the middle ear have been considered rare. The tremendous volume of middle ear surgery performed during the last 15 years has brought attention to numerous anomalies of the facial nerve, ossicles, and middle ear cleft, suggesting that middle ear anomalies are not as rare as once believed. This paper discusses anomalies of the descending and horizontal facial nerve which have been previously reported. The literature of anomalies of the ossicles is reviewed. A very rare anomaly of the carotid artery presenting in the middle ear is described and its surgical treatment outlined. Two anomalies of the middle ear associated with other branchial arch anomalies are reported and their treatment results discussed.
Adolescent↗
[Barotrauma of the inner ear. A review with 2 characteristic case reports].
Explore the source record for details and available documents.
Adult↗
Prostheses for stapes surgery.
A variety of different implants are available today for use by the otologic surgeon. All prostheses are well tolerated, and the risks of complication as a result of their implantation are comparable. The most commonly used prostheses are the wire-Teflon piston and the stainless steel bucket handle. Although the otologic surgeon has a wide variety of prostheses to choose from, most have a preference for one particular type. Results of hearing improvement following a successful stapedectomy is more a function of the surgeon's experience than of the type of prosthesis used. As James L. Sheehy, MD, so often says, "if a technique is working well for you, don't change for change's sake" (personal communication, 1994).
Ear Ossicles↗
[Idiopathic perilymph fistula].
This article presents 6 cases with idiopathic perilymph fistulae. The etiology of idiopathic perilymph fistula may be congenital malformation of the otic capule. Diagnosis of idiopathic perilymph fistula primarily depends on history and exploratory tympanotomy, but ENG-fistula test and positional audiometry are worth of diagnosing. During microsurgical procedure, attention must be paid to the presence of membrane of the round window niche. If a good repair of fistula is not followed by a good result, other lesions such as double labyrinth membrane rupture should be considered.
Adult↗
[Interference effects in the inner ear in sound stimulation of oval and round windows].
Explore the source record for details and available documents.
Ear, Inner↗
Congenital labyrintho-tympanic fistula -- a recently recognized entity in children.
A case of congenital labyrintho-tympanic fistula is reported. The possible anatomical pathways and main clinical characteristics are discussed together with a review of the literature. Special emphasis is made for early recognition in children, of this entity without invasive forms of investigation, and the proper surgical approach via tympanotomy is described.
Child, Preschool↗
Inner ear barotrauma.
Inner ear barotrauma was observed by compressing or decompressing guinea pigs. The barotrauma in compression was greatly influenced by auditory tube function, and, in the animals deprived of this function, we could observe far more severe damage of inner ear hair cells and far more frequent round window rupture than in animals not thus deprived. Barotrauma in decompression was brought about in guinea pigs not deprived of auditory tube function with a decompression speed of 0.1 kg/cm2/sec, which is so severe that even a healthy auditory tube could not endure it. It can be said that the middle and inner ear are more apt to be damaged in decompression than in compression.
Animals↗
Persistent inner ear injury after diving.
OBJECTIVE: The purpose of this multiple case report was to discuss the occurrence and cause of sudden sensorineural hearing loss after diving. STUDY DESIGN: The study design was a retrospective case review. SETTING: The study was conducted at an academic tertiary referral center. PATIENTS: In this multiple case report, two teenagers with unilateral sudden sensorineural hearing loss after diving, one from a starting block and one from a 1-m board, while performing school swimsports were included. INTERVENTION: The patients underwent diagnostic tympanotomy with sealing of the round and oval window membranes and a vasoactive rheologic therapy combined with corticosteroid treatment. MAIN OUTCOME MEASURES: The average pure-tone bone-conduction thresholds were calculated. The appearance of nystagmus, vertigo, and tinnitus was analyzed. RESULTS: Both patients experienced unilateral sudden deafness after performing a headfirst pike-type dive into a swimming pool. None of the patients contacted with the bottom of the pool. In one patient, a rupture of the round window was found intraoperatively. In the other patient, no rupture of the round or oval window was seen intraoperatively. In spite of sealing of the round window and application of vasoactive rheologic therapy, hearing did not improve significantly in either of the patients. CONCLUSION: Rupture of the round window may occur after diving even if the dive is performed from a low height into the water and the bottom of the pool is not contacted. Besides direct contusion to the external ear and barotrauma, other causes such as whiplash mechanism have to be considered.
Adolescent↗
Traumatic labyrinthine fistulas.
During the last 10 years, the rupture of the inner ear windows, as an entity, has been introduced in the differential diagnosis of the acute vestibulocochlear syndrome. Head trauma, Valsalva-like maneuvers and barotrauma due to diving accidents are now described as etiologic factors in the pathogenesis of labyrinthine fistula. Four cases were explored and repaired in the last four years in our department. Ataxia was the prominent symptom in three, while positional nystagmus and vertigo were consistent findings in all four cases. The definitive evidence of the fistula can be proved only by exploratory tympanotomy. In this report, the importance of the consideration of this entity in the differential diagnosis of vestibulocochlear syndrome in victims of traffic and diving accidents is emphasized.
Adolescent↗
Restoration of hearing with type V tympanoplasty.
Type V tympanoplasty with fenestration of the oval window and protection of the round window in a residual hypotympanic cavity can be considered as the last-chance procedure for rehabilitation of hearing in ears with 'canal wall down' or other conditions. The review of 64 cases suggests that restoration of hearing can be adequate in the majority of cases.
Adipose Tissue↗
[Experimental studies on the effect of labyrinth anesthesia].
Injection of tetracaine into the tympanic cavity inhibits, independently of histologic lesions of the round window membrane, the active electrogenic pump in the stria vascularis cells. The DC potential in the endolymph is reduced with increasing doses of tetracaine, while the K+-Cl- activity is unchanged for 120 min. This drug does not alter the permeability of Reissner's membrane. Near the stria vascularis area, the oxygen pressure in the endolymph increases significantly after the effects of 4% tetracaine.
Anesthesia, Local↗
Three-dimensional CT of the middle ear and adjacent structures.
Three-dimensional (3D) computed tomography of the middle ear and adjacent structures has been carried out in two cadaveric heads from axial and coronal high-resolution images. The structures shown on the images of the walls of the tympanic cavity are illustrated. The usefulness and limitations of the technique, in this region, are discussed: use of grey level volumes at the surface of the slices and the inclusion of structural landmarks is emphasized. The 3D representations show the anatomical spacial relationships of the small structures in and around the middle ear to advantage. The information may be of use in surgical orientation.
Cochlea↗