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PubMedDate not supplied

The intratemporal course of the facial nerve and its influence on the development of the ossicular chain.

Analysis of the information obtained from more than 110 malformations of the external and middle ear operated upon by the author (Gerhardt) leads to speculation as to their course of development. Of particular interest are the varying types of stapes malformations and the influence of variations in the course of the facial nerve on the development and shaping of the stapes. In the light of clinical examples, an attempt was made to interpret the variations in the course of the facial nerve and certain forms of stapes and incus malformation on the basis of the developmental processes in the area of the skull base and of the brain.

Ear↗
PubMedDate not supplied

Results of stapes operations with preservation of the stapedius muscle tendon.

The material consisted of 195 operated otosclerotic ears. In 101 ears the stapedial tendon was left intact and in 94 ears it was divided. The follow-up period was approximately 8.0 years. The stapedius reflex was tested in 85 ears with intact tendon and in 25 with divided tendon. It was elicited in 50 of the former but in none of the latter. Both bone and air conduction thresholds were postoperatively poorer in ears with preserved tendon than in the ears with divided tendon. Revision surgery was performed in 19 ears, 13 of which had an intact stapedial tendon. The reason for reoperating was usually the fixation of the stapedial crus at the oval window margin. The crus may have shifted because of the pull exerted by the stapedial muscle. In spite of the better circulation to the stapes and the long process of the incus, and of possible protection against loud noises, we cannot, in the light of our experiences, recommend preservation of the stapedius muscle tendon.

Adolescent↗
PubMedDate not supplied

Findings in a pair of temporal bones from a patient with secretory otitis media and chronic middle ear infection.

The histopathological changes in a pair of temporal bones from a 69-year-old woman who had secretory otitis media in the left ear and chronic middle ear infection in the right ear are described. Tympanostomy tubes had been placed in her left ear nine times. The perforation at the grommet showed no ingrowth of squamous epithelium; the fine structure of the tympanic membrane was normal. There were a few mucus strands present in the middle ear, which was lined with a one- to three-cell layer epithelium, where only a few secretory cells were found. In the right ear the thick tympanic membrane showed papillary projections of the squamous epithelium extending from the outer epidermal layer deep into the stroma and close to the collagenous layer of lamina propria. A large marginal perforation was present in the posterior quadrant, but there was no ingrowth of squamous epithelium from the canal into the middle ear. From the anterior margin, a concave veil-like sheet of squamous epithelium had grown onto the incus, chorda tympani and the stapes head. Numerous finger-like projections extended from the margin of this epithelium to the stapedial footplate and the epitympanum. The mucous membrane of the bony portion of the Eustachian tube in both ears was normal to the cartilage level, and the defective ventilation was in all likelihood caused by a dysfunction at the pharyngeal end of the Eustachian tube.

Aged↗
PubMedDate not supplied

Surgical treatment of chronic middle ear disease. 1. Myringoplasty and tympanoplasty.

Results of myringoplasty or tympanoplasty were evaluated in 225 ears followed for at least one year after surgery. Repair of the tympanic membrane with an underlay connective tissue graft (fascia in 90%) was successful in 97% of the ears. One late perforation developed 3 years postoperatively. The average postoperative air-bone gap was 4.8 dB in 88 cases of myringoplasty, the series including three ears with a rigid footplate. Rigid incus and malleus should not be mobilized but subjected to resection and reconstruction. Poor tubal function caused adhesive changes in one ear (1%). In tympanoplasty the average postoperative air-bone gap was 11.3 dB in 100 ears with stapes present and 20.6 dB in 36 ears with only the footplate remaining. Of the 137 tympanoplasty ears, 10 (7%) showed prominent adhesive changes. In 36 ears with cholesteatoma there was one recurrence 3 years later (3%). An air-bone gap of less than 20 dB was postoperatively noted in 94% of the ears undergoing myringoplasty and in 69% of the ears undergoing tympanoplasty.

Ear Diseases↗
PubMed1988

Temporal bone findings in cloverleaf skull syndrome.

Cloverleaf skull syndrome was first reported in 1960 by Holtermüller & Wiedemann as Kleeblattschädel-Syndrome. The case in the present report was that of a male infant 26 days old at the time of death. Besides a trilobed skull and abnormalities of the extremities, he had low-set ears, stenosis of both external auditory canals, a beak-like nose, microphthalmia, retentio testis and congenital dermal sinus-like anomaly at the coccygeal region. A chromosome study revealed a normal male karyotype. The right temporal bone showed some anomalies through the external and middle ears. The bony portion of the external auditory canal was narrowed. The middle ear cavity was filled by mesenchymal tissue devoid of cell components. The incus was almost attached to the lateral tympanic wall. In addition, the stapes was thickened and bent anteriorly. The sensory and neutral elements of the inner ear were normal.

Craniosynostoses↗
PubMed1991

Laser labyrinthectomy in humans.

This paper describes the feasibility of labyrinthectomy of only the vestibular part using argon laser in humans. In animal experiments, the utricular and saccular maculae were completely destroyed using argon laser with the otoprobe of the HGM system via the oval window, following stapedectomy. The human utricular and saccular maculae can be approached in a similar manner. Several approaches to the nerves and ampullae of the anterior and lateral semicircular canals are discussed. The most appropriate method to abolish the function of the ampullae is to sever the ampullary nerves. This can be done through the widened oval window with the argon laser otoprobe. After laser application, the oval window is covered by a piece of perichondrium. A stapes prosthesis is placed on the long process of the incus. Laser singular neurectomy may be used to sever the nerve to the posterior ampulla.

Animals↗
PubMed1996

The pars flaccida middle ear pressure and mastoid pneumatization index.

The degree of pars flaccida retraction and the levels of mastoid pneumatization were assessed and correlated in 388 adults with intact pars tensa. Poorly pneumatized mastoids were found to be associated with retraction of pars flaccida; the poorer the pneumatization, the deeper the retraction. Well pneumatized mastoids were usually associated with normal position of the pars flaccida. The pars flaccida was previously also shown to retract in face of ME negative pressure--and its degree can be seen to be an index of ME negative pressure. Thus, the correlation of deeper degrees of pars flaccida retractions with mastoid hypopneumatization (and vice versa) lends strength to the studies which show the mastoid pneumatic system to have a function of a passive ME pressure buffer. This observation lends further evidence as to why ears with poorly pneumatized mastoids are a priori at risk to develop complications such as SOM in adults, tympanic membrane retractions and perforations, incus necrosis or retraction pocket cholesteatoma. Ears with a large pneumatic system are hardly at such risk.

Ear Diseases↗
PubMed1997

A dynamic and harmonic damped finite element analysis model of stapedotomy.

This study was undertaken in an attempt to better understand the mechanics of sound transmission at the footplate following stapedotomy. The insertion of a Teflon (polytetrafluoroethylene) stapes prosthesis introduces new constraints within the reconstructed ossicular chain which have an effect on the normal vibration patterns of the tympanic membrane. In a finite element model of the ear, constraints have been reproduced as a series of spring constants in the incus/prosthesis/footplate interfaces incorporating damping to simulate the impedance of the inner ear. At zero damping, the frequency response at the pseudo stapes footplate exhibit several maxima and minima between 800 Hz and 2.5 Hz. At higher damping values, these maxima and minima become smoothened out with two or three naturals occurring over the same frequency range. Severe ankylosis of a diseased footplate is reproduced by over-damped conditions. The umbo, incus and stapes footplate vibrate in phase with similar frequencies at light damping levels. The movement of the prosthesis at the pseudo-footplate can be large in the out of plane axis of the ossicular chain, unless sufficient support is provided at the reconstructed footplate. Clinically, this would suggest the vein graft interposed between the piston and stapedotomy hole should endow resistance and elasticity to the system.

Acoustics↗
PubMed1988

Tympanometry using a sweep-frequency probe tone and its clinical evaluation.

In this new tympanometric system, air pressure in the external meatus is kept constant at either -200 daPa or 0 daPa. The frequency of the probe tone is swept from 220 to 2,000 Hz (or 2,500 Hz, if necessary) in 4 s. During this frequency sweep, sound pressure in decibels and phase angle in degrees in the external meatus are sampled and the differences in sound pressure and phase angle measured at -200 and 0 daPa pressures are computed. These results are figured as a frequency-sound pressure curve and a frequency-phase angle curve. From the study on 8 fresh human cadaver temporal bones, four parameters in these curves are selected by discriminant analysis to provide diagnostic criteria: the minimum value and the 0-cross frequency of the frequency-sound pressure curve and the maximum value and its frequency of the frequency-phase angle curve. Normal parameters were determined in 50 normal ears. Evaluation of 40 patients with ossicular disorders revealed that 10 out of 12 cases of ossicular discontinuity and 5 out of 6 cases of malleus and/or incus fixation were correctly diagnosed. For stapes fixation, the diagnosis was correct in 12 out of 22 ears. This system is useful in the clinical diagnosis of ossicular disorders, producing a collection of curves and parameters that are distinctively different for the ossicular discontinuity and the ossicular fixation.

Acoustic Impedance Tests↗
PubMed1997

[Ossicular vibration changes associated with pressure changes in inner ear and cerebrospinal fluid in guinea pigs].

The effects of increase in the inner ear and cerebrospinal fluid (CSF) pressures on the vibration of the ossicular chain were studied in guinea pigs by using a laser doppler vibrometer. Velocity of the malleus umbo and that of the incus long crus in response to a constant sound stimulus of 90dB SPL at the tympanic membrane were measured at 13 frequencies between 0.125 kHz and 10 kHz. Loading pressures to the inner ear and the CSF were adjusted by changing the height of a saline bottle hooked up to the respective site by a 24G Teflon catheter. The pressure was monitored with a pressure transducer placed in the catheter. Positive and negative pressure loads to the inner ear decreased the velocity of the umbo at low and high frequencies. The maximum change was 4.7 dB at 0.125 kHz with a positive pressure load of 400 mmH2O. Similar results were obtained for the umbo and the long crus by a positive pressure load to the CSF, with the exception that the umbo velocity showed no change at higher frequencies. These results suggest that the inner ear and CSF pressure changes affect not only the function of the organ of Corti but also the vibration of the ossicular chain. These changes occurred mainly at lower frequencies.

Animals↗
PubMed2002

[Neurinoma of tympanic plexus: a case report].

We report a unique case of neurinoma originating from the tympanic plexus. A 23-year-old man reparting hearing impairment was found in otoscopic examination to have a tumor contour identified through the ear drum. Computed tomography showed that the tumor extended from the hypotympanum to the mesotympanum, eroding the promontory. A small specimen obtained after myringotomy indicated neurinoma. The man did not report facial weakness or taste disturbance. When we operated to remove the tumor, we found the long crus of Incus had disappeared and the stapes superstructure was dislocated upward due to the tumor expanse. Pathologically, the extirpated tumor was neurinoma of Antoni A. A postoperative salivary gland function test using Tc showed hypofunction at the lesion side of the parotid gland. We surmise that neurinoma originated from the tympanic plexus because of its location and its lack of a relationship to the chorda tympanic nerve or facial nerve.

Adult↗
PubMed1993

[Clinical views of cases with discontinuity of the ossicular chain].

It is well known that reconstruction for discontinuity of the ossicular chain, without inflammatory disease, has a good prognosis. Eleven cases of congenital ossicular chain malformation without ossicular fixation and 6 cases of ossicular chain injury due to the head trauma or an earpick , were treated surgically. The method of reconstruction and the prognoses, according to short-term and long-term follow up, were studied in these 17 cases. The following results were obtained: 1) In almost all cases, the pure tone audiograms were flat or slightly rising types, and the mean air conductive hearing loss was about 60 dB. Only 2 cases showed the falling type with conductive hearing loss. Connective tissue was observed at the incudo-stapedial joint intraoperatively in these two cases. 2) Mean hearing improvement was in 31.8 dB in the low frequency region (125, 250, 500 Hz), 22.7 dB in the middle frequency region (500, 1000, 2000 Hz), and 12.9 dB in the high frequency region (2000, 4000, 8000 Hz), within 3 weeks after operation, in all 17 cases. 3) No clear changes in hearing level were seen postoperatively, for the four periods evaluated; 1-3 weeks, 1-3 months, 4-6 months and over 7 months in all cases. 4) The cases in whom the reconstruction was performed between the incus and stapes, especially the foot plate of the stapes, showed poor hearing recovery. 5) There was no relation between hearing recovery and the prostheses used in reconstructions. However, it was thought that pieces of the patient's own cartilage or bone should be used whenever possible.

Adolescent↗
PubMed1994

[Computed tomography findings in middle ear anomaly].

The efficacy of computed tomography (CT) of the temporal bone was studied in 45 ears with a middle ear anomaly but whose tympanic membranes were normal. The plane of the film was 30 degrees oblique to the orbito-meatal line. Four otorhinolaryngologists made radiological diagnoses of the CT film without having any information about the patients. CT films of 40 normal ears were also evaluated and served as controls. The incudo-stapedial joint (I-S joint) and the stapes were visualized in all control group subjects. The percentage of correct diagnoses was 77.8% for separation of the I-S joint, and 75.6% for fixation of the stapes. The monopedal stapes was not visualized. Fixation of the malleus and the incus could not be diagnosed correctly. Abnormalities in the location of the facial nerve were visualized in a few ears. CT of the temporal bone was clinically useful for differentiating I-S joint separation and fixation of the stapes.

Adolescent↗
PubMed1994

[Direct observation of the tympanic cavity by superfine fiberscopy through the eustachian tube].

It was impossible to observe directly the tympanic cavity with the ear drum intact. The superfine fiberscope, developed by the Department of Otolaryngology, Tokyo Medical College, makes it possible to observe the tympanic cavity through the eustachian tube without any surgical intervention such as myringotomy. This fiberscope is flexible and very fine, having an outer diameter of 0.6-0.8mm. Using this new fiberscope, the following structures can be observed: the handle of the malleus, the long process of the incus, the incudostapedial joint, the head of the stapes, the crus of the stapes, the tendon of the tensor tympani muscle and the promontory. Observation results are presented for 138 ears with various disorders: cholesteatoma, tympanosclerosis, congenital malformation, ossicular dislocation, otosclerosis, otitis media with effusion, chronic otitis media, etc. All patients could be tested with local anesthesia in the outpatient clinic except very young children. The findings were easily recorded on either photographs or video tapes. This superfine fiberscope was of great value in the diagnosis of pathologies affecting middle ear structures in outpatient clinics, since no surgical intervention was necessary in the procedure. In addition, it was very useful for making highly detailed studies and for discussion after the examination.

Adolescent↗
PubMed1995

[Three-dimensional CT of the ossicles of the middle ear].

This study was performed to evaluate the usefulness and limitations of three-dimensional (3-D) imaging of the ossicular chain in the middle ear by high speed helical CT. One dissected human temporal bone, five normal ears, and twelve diseased ears (trauma, ossicular anomaly, cholesteatoma, chronic otitis media) were scanned in 1.0mm slices and reconstructed at a thickness of 0.2-0.5mm. All 3-D CT specimens can be observed in any plane and from any direction. Ossicular 3-D CT temporal bone images were reconstructed as if the malleus, incus and stapes were being observed under a microscope. No defect in the ossicles or their joints was seen in the images. The entire structure of the stapes could not be represented by conventional two-dimensional CT, but the 3-D CT in our study showed the head, crus and foot plate of the stapes in detail. Ossicular 3-D CT images of normal ears yielded the same findings as those recorded in the temporal bone. Preoperative diagnostic findings of ossicles in diseased ears were very useful. 3-D CT was diagnostic and its accuracy was confirmed by surgical observations, especially in ossicular anomalies. 3-D CT was also an important method of postoperative evaluation of ossicular reconstruction, i.e. TORP and PORP. It could represent the anatomical relation between prosthesis and the oval window. Postoperative hearing improvement can be compared with 3-D CT findings. High-speed helical CT can scan an object more quickly and clearly than conventional CT, and its biological damage in humans is less than that of other methods.

Adolescent↗
PubMed1999

Chronic inflammatory ear disease and cholesteatoma: creation of auxiliary attic aeration pathways by microdissection.

HYPOTHESIS: The attic compartments, except for Prussak's space, are aerated through the tympanic isthmus. The aim of this study was to develop aeration pathways that would bypass the isthmus in surgery for chronic inflammatory ear disease and cholesteatoma. BACKGROUND: Microdissection of the epitympanum has shown that the anterior attic and the supratubal recess are separated by the tensor fold, the excision of which creates a large new aeration pathway. METHODS: Earlier surgical experience was reexamined as to the access to the tensor fold. Twenty temporal bones were dissected to create clinically useful new surgical routes for tensor fold removal in the presence of an intact ossicular chain. RESULTS: An endaural atticotomy, extended to the supratubal recess, allows excision of the tensor fold; however, the excision must be performed blindly. Cutting the neck of the malleus to allow lateral lifting of the manubrium exposes the tensor tendon and allows rapid excision of the fold. The elasticity of the tendon assists in approximation of the cut edges. In canal wall up surgery, removal of the lateral attic bone until the root of the zygoma exposes the anterior surface of the head of the malleus and the lateral portion of the transverse crest. Drill-out of the crest leads directly to the posterior side of the tensor fold, allowing its excision under direct vision. Thinning of the attic bone lateral to the body and short process of the incus allows simultaneous removal of the lateral incudomalleal fold. CONCLUSIONS: When the ossicular chain is discontinuous, tensor fold resection can be made under direct vision. With an intact chain, cutting of the neck of the malleus used in tympanic glomus tumors causes no hearing changes, allows complete fold excision, and is adaptable to chronic ear surgery. The frontolateral attic route for removal of tensor fold, together with the lateral incudomalleal fold, can be used in the canal wall up surgery to improve attic aeration.

Cholesteatoma, Middle Ear↗
PubMed1999

Acute necrotizing otitis media in an infant: a case report.

Acute necrotizing otitis media (ANOM), an uncommon but severe form of bacterial otitis media, frequently causes distressing sequelae if not properly diagnosed and treated. A four-month-old female infant initially became ill with intermittent fever, followed by left facial nerve paralysis and left otorrhea four days later. Microscopic examination of the left ear revealed congestion and swelling of the external ear canal, perforation of the eardrum and erosions on the malleus. Culture of pus from the otic lesion grew Pseudomonas aeruginosa. The patient's condition did not improve despite systemic administration of antibiotics; thus, surgical intervention was arranged. During the operation, near-total perforation of the eardrum, a dislodged incus, cholesteatoma-like matrix around the stapes, and granulation tissue occupying the middle ear and mastoid cavities were noted. Radical mastoidectomy was conducted and pathologic examination of the surgical specimen disclosed necrotic changes in both soft and bony tissues. The patient recovered soon after surgery. Her fever subsided one day after surgery and the patient was discharged in a stable condition 12 days later. However, she still had left facial nerve paralysis six months later.

Acute Disease↗
PubMed1999

Proximal symphalangism and congenital conductive hearing loss: otologic aspects.

OBJECTIVE: Results of stapedectomy are reported in a Belgian 26-year-old woman and two Dutch brothers having the proximal symphalangism syndrome (McKusick 18580). STUDY DESIGN: Case reports are presented. A review of the results of ear surgery for congenital conductive hearing loss in this syndrome is given. SETTING: The Belgian patient was treated in a general hospital. The Dutch patients were treated in a university hospital, which was a tertiary referral center. PATIENTS: Patients were referred to have an evaluation of their hearing impairment. INTERVENTION: Based on the syndromal diagnosis and based on routine audiometric tests, a congenital ossicular fixation was considered to be the cause of the hearing loss. By exploratory tympanotomies, this was confirmed. Reconstructive procedures including stapedotomy were performed. MAIN OUTCOME MEASURES/RESULTS: Long-term audiometric data are presented to evaluate the outcome of the surgical interventions. CONCLUSIONS: Congenital stapes ankylosis eventually combined with a congenital fixation of the short process of the incus in the fossa incudis, causing the congenital conductive hearing loss. Surgical intervention is very successful in most reported cases, but negative side effects are incidentally found as well.

Adult↗