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At least 685 records · Page 38Linked to original sources
PubMed2006

Should we use ossicular remnants in ossicular reconstruction following cholesteatoma removal?

The remnants of the acoustic ossicles have been used in ossicular reconstruction during mastoid surgery for many decades. The present study assessed the status of the acoustic ossicles in 114 patients (57 with cholesteatoma and 57 without) during surgery for chronic otitis media using the operating microscope. In 52 cases, the ossicles (malleus and/or incus) were assessed using both the surgical and scanning electron microscope in order to reveal any erosions and compare the findings. From the 57 operated ears with cholesteatoma, 45 (79%) had ossicular erosion whereas 12 (21%) did not. In the group of 57 operated ears with chronic otitis media without cholesteatoma, 33 (58%) had ossicular erosion whereas 24 (42%) did not. This difference was statistically significant (p = 0.02). With regard to the 52 operated cases who were studied with both microscopes, in the cholesteatoma patients the surgical microscope was not able to reveal any ossicular erosions in 39% of the cases, whereas the scanning electron microscope revealed moderate or severe erosions in the same ears. This suggests that the operating microscope is not reliable enough to determine if ossicular remnants can be used in ossicular reconstruction following cholesteatoma surgery. There is a considerable risk that epithelia or other cholesteatoma particles remain in the areas of erosions that cannot be seen with the operating microscope. The use of such ossicular remnants may lead to cholesteatoma recurrence and failures in mastoid surgery. Therefore, autoclaving or alternative prosthesis may be considered in such cases.

Adult↗
PubMed2006

Key features of the human middle ear.

The human middle ear was investigated using a generalised circuit model which can simulate the spatial vibrations of the ossicular chain. The behaviour was observed for acoustic excitation via the normal air conduction path and for mechanic excitation due to shaking the complete temporal bone. More insight into the functionality of the middle ear was obtained by also considering abnormal conditions such as stiffenings. It turned out that the mammalian middle ear is superior to a columella ear due to its particular design. The placement of comparably heavy bones (malleus head and incus body) outside the main transmission path between the manubrium and the stapes footplate in combination with a very flexible ossicular chain creates several favourable properties.

Acoustic Stimulation↗
PubMed1994

Study of pterygospinosus muscle in human fetuses.

The arrangement of the pterygospinosus muscle was analyzed in 5 human fetuses. The pterygospinosus muscle extends from the posterior border of the lateral lamina of the pterygoid process to Meckel's cartilage. Such an arrangement would permit its action on the joint formed by Meckel's cartilage and the incus of the middle ear. The pterygospinosus muscle is a remnant of the masticatory muscle group. The relationships of the pterygospinosus muscle with the mandibular nerve and its branches and the maxillary artery and its branches were analyzed.

Computer Simulation↗
PubMedDate not supplied

Etretinate-induced malformation of the first two branchial arches: differential staining and microdissection study of embryonic cartilage.

Malformations of the cranial base, temporal bone and middle ear were induced in the offspring of Sprague-Dawley rats by a single intraperitoneal injection of 10-30 mg/kg etretinate (Tigasone) at days 8.5-10.5 of gestation. By differential staining of the embryonic craniofacial cartilage and bone, and microdissection of the otomandibular complex, the induced malformations were studied specifically. Defective formations of Meckel's cartilage and the cartilaginous skull base were found to be prominent features of the malformation. The malformation included defective middle-ear ossicles; especially the malleus and incus were fused with a shorter than normal long process and manubrium. In conjunction with the distal part of Meckel's cartilage, mandibular micrognathia was observed. All of the malformed tissues are derivatives of the first and second branchial arches. The teratogenically induced defects in the rat embryos show some similarities to the clinical syndromes of the first and second branchial arches in man.

Abnormalities, Multiple↗
PubMed2001

Intraoperative assessment of stapes movement.

A method is described that allows, for the first time, intraoperative vibration modes assessment of the acoustically stimulated stapes by means of scanning laser Doppler interferometry (LDI). The study was designed to answer the following questions: 1) Is LDI practical for taking measurements during surgery? 2) Are the results comparable to the findings in temporal bone preparations? and 3) Do the vibration characteristics of the stapes change after the posterior incudal ligament is detached from the incus? Seven patients with profound bilateral hearing loss who were undergoing cochlear implantation were included in the study. The measurement system was easily applicable for intraoperative measurements and allowed contact-free analysis with very high accuracy. No major differences in the results from the live human subjects and temporal bone preparations were observed. The stapes movement was predominantly pistonlike at the lower frequencies and became complex at higher frequencies. Sacrificing the posterior incudal ligament had no statistically significant effect on stapes vibration.

Acoustic Stimulation↗
PubMed2006

Results after revision stapedectomy with malleus grip prosthesis.

Revision stapedectomy with a malleus grip prosthesis is a technically challenging otologic procedure. The prosthesis is usually longer and extends deeper into the vestibule than a conventional stapes prosthesis, creating the potential to affect the vestibular sense organs. The prosthesis also bypasses the ossicular joints, which are thought to play a role in protecting the inner ear from large changes in static pressure within the middle ear. The prosthesis is in close proximity to the tympanic membrane, thus increasing the risk for its extrusion. We reviewed our experience with revision stapedectomy with the Schuknecht Teflon-wire malleus grip prosthesis in 36 ears with a mean follow-up of 23 months. The air-bone gap was closed to within 10 dB in 16 ears (44%) and to within 20 dB in 26 ears (72%). The incidence of postoperative sensorineural hearing loss was 8% (3 ears). There were no dead ears. Extrusion of the prosthesis occurred in 1 case (3%). Nearly 50% of patients reported various degrees of vertigo or disequilibrium during the first 3 weeks after surgery. These vestibular symptoms resolved by 6 weeks in all but 1 case. We did not find evidence of damage to the inner ear due to the length of the prosthesis or due to the potential for direct transmission of changes in static pressures within the middle ear to the labyrinth. Our results are similar to those published in the literature for malleus attachment stapedectomy and conventional revision incus stapedectomy.

Adult↗
PubMedDate not supplied

Goblet cell population in the normal middle ear and Eustachian tube of children and adults.

On 54 temporal bones from entirely normal prematures and newborn infants, children, and adults, 30,000 to 90,000 counts of goblet cells were done in different parts of the Eustachian tube and middle ear. In the Eustachian tube, normal prematures showed a very low density of goblet cells in all localities, increasing in the pharyngeal parts gradually through childhood and reaching in the normal adult a very high density in the pharyngeal orifice. There are no differences in density between the medial and lateral wall, but in some parts a decrease of density towards the tubal roof. In the middle ear the density is low in normal prematures, increasing slightly in infants, and decreasing again during the age range 7-14 years and in adults. Goblet cells are present in all middle-ear localities, but in markedly decreasing density in this sequence: hypotympanum anteriorly, posteriorly, promontory anteriorly, in the middle, epitympanum, niche of oval window, antrum, niche of round window, mastoid process, incus, and promontory posteriorly.

Adolescent↗
PubMedDate not supplied

Quantitative evaluation of postnatal bone growth in the auditory ossicles of the dog.

The postnatal bone growth (appositional and internal) in the auditory ossicles and in the tibia of three mongrel dogs was studied by means of tetracycline and alizarin labeling. The appositional growth is characterized by an increase in the external dimensions of the auditory ossicles within the first month of postnatal life. No trace of bone deposition was found after this period of time. The patterns of internal growth are: 1) the rate of primary osteon formation shows the same value in the incus and malleus; 2) these values are always less than those in the primary osteons of the diaphysis of the tibia of the same dog; 3) the time required for the formation of these osteons in the auditory ossicles, like in the other parts of the skeleton, increases significantly with age.

Animals↗
PubMedDate not supplied

Stapedectomy - long-term report.

The long-term results with large fenestra stapedectomy with vein graft and Teflon piston are compared with results with the small fenestra stapedectomy with teflon piston directly into the vestibule. There were 1,943 operations in the former group and 2,155 in the latter when compared in 1970. One hundred consecutive patients from the beginning of each group with follow-up to present were compared. Results were generally the same with no great change in 15 and 20 years as compared to those at 5 years. The complication of perilymph fistula was caused by creating an opening in the footplate much larger than the prosthesis and was eliminated by interposing a living oval window seal if the opening was much larger than the prosthesis and a flap of lining membrane from the promontory when it was not. Other factors that influence a good result are discussed, including the type and the diameter of the piston used, the type of living oval window seal and the method of attachment to the incus. The small fenestra operation was found to be superior to the large, not only for the hearing gain achieved, but the case of performance and the freedom from complications due to migration of the prosthesis and/or the oval window seal. At present we have done about all that can be done for the conductive components. What remains is the sensorineural component which our studies indicate may be due to an autoimmune response.

Cochlear Implants↗
PubMedDate not supplied

Evaluation of three cyanoacrylate glues for ossicular reconstruction.

We evaluated and compared the separate effects of ethyl, isobutyl, and fluoroalkyl cyanoacrylate on the promontory mucosa and surgically disarticulated incudostapedial joint in the adult cat middle ear. The animals were sacrificed at 10-, 30-, and 60-day intervals after glue application. All three cyanoacrylates elicited a chronic inflammatory response when placed directly on the promontory mucosa. The use of ethyl and isobutyl cyanoacrylate resulted in persisting discontinuity of the incudostapedial joint with erosion of the incus. Fluoroalkyl cyanoacrylate maintained incudostapedial continuity without ossicular erosion. Ethyl and isobutyl cyanoacrylate are probably not appropriate for middle ear surgery. The less toxic fluoroalkyl cyanoacrylate may be useful as an ossicular adhesive in selected cases. Our findings are further contrasted with those obtained in similar studies with methyl and butyl cyanoacrylate. The effects of each of the five cyanoacrylates are reviewed in the continuing search for a safe and effective ossicular adhesive.

Animals↗
PubMedDate not supplied

Klippel-Feil syndrome with conductive deafness and histological findings of removed stapes.

The Klippel-Feil syndrome is usually associated with sensorineural hearing impairment, but rarely is it associated with conductive or mixed deafness. A 22-year-old female presented with fusion of the cervical vertebrae, torticollis, scoliosis, pterygium colli, the Sprengel deformity with an omovertebral bone, concavity of the thorax and conductive hearing impairment of the right ear. Tympanotomy disclosed an atrophic long process of incus and a fixation of the stapes footplate, and stapedectomy was performed with immediate postoperative improvement of hearing. However, she developed a sudden hearing loss with dizziness soon after she had physical exercise on the 15th postoperative day, and revision surgery revealed a perilymph fistula of the oval window. Histological investigations of the removed stapes showed no specific osseous changes but hyperostosis of the posterior edge of the footplate. The literature is reviewed and the etiology of the conductive deafness and the perilymph fistula is discussed.

Adult↗
PubMedDate not supplied

Stapes surgery in patients with osteogenesis imperfecta.

Osteogenesis imperfecta is not in itself a contraindication to stapedectomy. Thirty stapedectomies were performed on 24 patients with osteogenesis imperfecta. Thin ossicles, crural fractures, and thick, mushy, granular footplates predominate in this condition. Deficient, short crura that did not contact the footplate were noted in three patients; this is possibly a new clinical observation. Three times in this small series the endosteum was so thick that it was possible to fenestrate the soft, granular, mush-like footplate without invading the vestibule. Extreme caution in handling the incus is necessary. Conductive hearing loss can be relieved through stapedectomy in patients with osteogenesis imperfecta with about the same level of predictability as in those with otosclerosis.

Adult↗
PubMedDate not supplied

Clinical assessment of ossicular mobility by a ceramic vibrator designed for implantable hearing aids.

Ossicular mobility was assessed by direct coupling of a piezoelectric ceramic vibrator to the ossicles during middle ear surgery. The sites excited were body of the incus, head of the stapes, and footplate of the stapes through a hydroxyapatite ceramic strut. The threshold of the vibratory hearing was determined by the patient's response as a minimum audition, and the vibration threshold was obtained by subtracting the preoperative bone conduction threshold from the vibratory hearing threshold. The results were analyzed by the state of hearing after the operation, which revealed that a patient with a good vibration threshold during the operation had a tendency to get good postoperative hearing. This may mean that postoperative hearing can be predicted to some extent during the operation by the measurement of ossicular mobility.

Adolescent↗
PubMedDate not supplied

Malleus grip prosthesis.

The malleus grip prosthesis is designed for ears with conductive hearing loss caused by pathologic conditions of the stapes in association with pathologic conditions of the malleus or incus. The malleus grip procedure was performed on 220 ears, and follow-up studies are available on 203. Mild to profound sensorineural hearing losses occurred in 16 (8.37%). The remaining 187, on the first postoperative test, had an average air-bone gap of 14 dB, and subsequent examinations on 100 of them showed no significant change with the passage of time. The procedure is technically more difficult than stapes surgery for otosclerosis, and success is highly dependent upon selection of appropriate cases and meticulous implantation of the prosthesis.

Deafness↗
PubMedDate not supplied

Reconstruction of the ossicular chain with hydroxyapatite implants.

This paper describes the clinical results of the application of dense hydroxyapatite assembly prostheses. A study of 60 patients with hydroxyapatite incus prostheses revealed an air-bone gap closure within 20 dB in 86.6% of the cases, and an air-bone gap closure of less than 10 dB in 60.6%. No improvement was seen in 5% of the patients. The follow-up period varied from 1 to 4 years with an average of 2 years, and the hearing gain remained constant during this period. Hydroxyapatite may be considered a useful material for reconstructive middle ear surgery.

Adolescent↗
PubMedDate not supplied

Otologic complications following temporomandibular joint arthroscopy.

The recent application of arthroscopic surgical techniques to the temporomandibular joint (TMJ) has facilitated the diagnosis and treatment of TMJ disorders. However, as TMJ arthroscopy is performed more frequently, new complications are being recognized. We report three patients who developed severe otologic complications following TMJ arthroscopy. Two sustained complete or severe sensorineural hearing loss and severe vertigo from trauma to the ipsilateral ear. The third patient had complete facial paralysis from trauma to the facial nerve in the middle ear and a conductive hearing loss from incus dislocation. Complete hearing loss and facial paralysis from trauma to the main trunk of the facial nerve have not been reported previously as complications of TMJ arthroscopy.

Adult↗
PubMed1997

Mechanics of type IV tympanoplasty: experimental findings and surgical implications.

In a type IV tympanoplasty, the stapes footplate is directly exposed to incoming sound while the round window is "shielded," usually with a fascia graft. Postoperative hearing results are quite variable, with air-bone gaps ranging from 10 to 60 dB. A cadaveric human temporal bone preparation was developed to investigate the middle ear mechanics of this operation to identify causes of variable results and to test predictions of a recently described theoretic model of type IV tympanoplasty. The ear canal, tympanic membrane, malleus, and incus were removed so as to expose the stapes and round window to the sound stimulus. A "cavum minor" chamber (air space adjacent to the round window) was constructed around the round window niche. The round window could be isolated from sound by placing an acoustic shield over this chamber. The mechanical properties of the shield, cavum minor, annular ligament, and round window membrane were varied experimentally. Stapes velocity as determined by an optical motion sensor was used as a measure of hearing level. The largest stapes velocity occurred with a mobile stapes and round window, a stiff shield, and a well-aerated cavum minor. Partial fixation of the stapes or round window caused a decrease in stapes velocity. Acoustic shields of conchal cartilage or Silastic silicone rubber sheeting (approximately 1 mm thick) provided near-optimal shielding. A temporalis fascia shield resulted in a stapes velocity 10 to 20 dB less than that seen with a cartilage or Silastic silicone rubber shield at low frequencies. A cavum minor air space as small as 16 microL was sufficient for unrestricted stapes motion, provided the air was in contact with the round window membrane. These results qualitatively matched predictions of our model, but there were some quantitative differences. The clinical implications of our results are that in order to optimize postoperative hearing, the surgeon should 1) preserve normal stapes mobility, preferably by covering the footplate with a very thin split-thickness skin graft, not a fascia graft; 2) reinforce a fascia shield with cartilage or Silastic silicone rubber; 3) create conditions that promote aeration of the round window niche; and 4) preserve the mobility of the round window membrane.

Adult↗
PubMed1998

Otological manifestations of CHARGE association.

The combined findings of abnormalities of the incus and stapes, absence of the oval window, absence of the stapedius muscle (with absent pyramidal eminence and tympanic sinus in most cases), and abnormalities of different parts of the inner ear (dysplastic cochlea, hypoplastic or dysplastic vestibule, and absent semicircular canals) are characteristic of the CHARGE association. Computed tomography and magnetic resonance imaging using 1-mm-thick contiguous slices proved useful in demonstrating the broad spectrum of temporal bone abnormalities in patients with the CHARGE association.

Adolescent↗