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At least 19 recordsLinked to original sources
PubMedDate not supplied

On the statics of malleus and incus and on the function of the malleus-incus joint.

An electromagnetic probe was used for statistical measurements on human temporal bone preparations in the malleus-incus region. When forces of 5 and 10 mN (milliNewton) were applied to certain points, the displacement of the malleus was considerably greater close to the umbo than in the region of the short process. According to the lever laws, a pivot was determined which was situated approximately in the mass centre of malleus and incus if two measuring points were chosen which were situated close to the umbo. The pivot was far outside the mass centre when the measuring points were closer to the head of the malleus. The conclusion was that statistically both auditory ossicles have no fixed pivot; rather, they are in a position to adapt to each oscillation of the tympanum. When forces were applied alternately at the malleus and incus with the same lever arm, a different displacement was measured, varying with the force applied. Greater forces led to more pronounced differences in displacement than did smaller forces. When forces of1 mN and below were applied, no differences in the displacement were ascertained. This shows that the malleus-incus joint was flexible if greater forces were applied. In dynamic terms, we can assume the existence of a protective mechanism about 120 dB.

Ear Ossicles↗
PubMed2004

Malleus relocation in ossicular reconstruction: managing the anteriorly positioned malleus: results in a series of 268 cases.

OBJECTIVE: The objective of this study was to report an original method of malleus relocation allowing for better placement of both partial and total prostheses in ossicular reconstruction. STUDY DESIGN: We conducted a retrospective review of clinical and audiometric findings. SETTING: A tertiary referral center. MATERIALS AND METHODS: This is a study of 268 patients who underwent ossiculoplasty surgery from October 1997 to October 2000 for chronic otitis media, noninflammatory disease, and otosclerosis revision. Malleus relocation with total and partial ossicular replacement prostheses was used in all cases. Audiometric assessment included pre- and postoperative audiometric evaluation using conventional audiometry. Air-bone gap, bone-conduction thresholds, and air-conduction thresholds were measured. RESULTS: A postoperative air-bone gap closed to within 10 dB was achieved in 56% of cases. An air-bone gap smaller than 20 dB was obtained in 78% of cases. Postoperative improvement of air-conduction thresholds superior to 20 dB was found in 41.5% of cases. The postoperative bone-conduction thresholds were unchanged in 98% of cases. One case of total postoperative sensorineural hearing loss was seen in this series (0.4%). Extrusion of the protheses was not observed in this series. Follow up ranged from 6 to 36 months (mean, 12.4 months). CONCLUSION: This study shows that malleus relocation is a safe and efficient technique for ossicular reconstruction. The ideal position of the relocated malleus allows easier and more stable placement of middle ear prostheses.

Adolescent↗
PubMed2005

Malleus-to-footplate versus malleus-to-stapes-head ossicular reconstruction prostheses: temporal bone pressure gain measurements and clinical audiological data.

HYPOTHESIS: Several clinical reports suggest that if the stapes superstructure is intact, ossicular reconstruction should be made to the stapes head rather than the footplate to achieve a better hearing outcome. To test this hypothesis, we compared the in situ mechanical performance of hydroxylapatite (HA) malleus-to-stapes-head (MSH) ossicular reconstruction prosthesis (ORP) with malleus-to-footplate (MFP) ORP, both manufactured by Project HEAR. BACKGROUND: ORPs are commonly used to replace a missing or deficient incus. However, hearing outcomes are highly variable, depending on the ORP material, design, surgical technique, and ORP positioning. METHODS: Cochleo-vestibular pressure measurements in human cadaveric temporal bones for the HA MFP ORP have been reported by Puria et al. (2005). In the present study, the ear canal pressure Pe and cochleovestibular pressure Pv were measured in cadaveric temporal bones with intact incus, removed incus, and MSH ORP reconstruction. The relative loss in gain, Lmsh, is defined as the ratio of Pv with reconstructed MSH ORP to intact incus and compared with Lmfp. A retrospective clinical audit of the pre- and postoperative audiologic results of patients who had undergone ossiculoplasty with either MSH or MFP ORP was conducted for comparison. RESULTS: For the 0.5 to 3 kHz frequency range, Lmsh magnitude is 6.2 dB lower than the Lmfp magnitude (p = 0.05). The retrospective audit of audiologic results after ossiculoplasty with either MSH or MFP ORP revealed a similar difference in gain between the two ORP designs with air-bone gap differences of 7.6 dB (p = 0.04) and air conduction threshold differences of 8.0 dB (p = 0.13) for these patients. CONCLUSION: The MFP ORP showed better average pressure gain compared with the MSH ORP across the speech frequencies. Surgeons performing ossiculoplasty with designs similar to Project HEAR HA ORPs, where there is direct columella-like connection between the malleus and stapes, should consider using the MFP ORP design to achieve a better postoperative audiologic result, even when the stapes superstructure is intact.

Aged↗
PubMed2004

[Surgery for tympanosclerotic stapes fixation accompanied by malleus fixation at the anterior malleus: report of 2 cases].

Most tympanosclerotic stapes fixation involves fixation or erosion of the malleus and/or incus. This status of the ossicular chain is one reason that ossiculoplasty for tympanosclerotic stapes fixation is more difficult than that for otosclerosis. In some cases, the malleus is fixed only at the anterior, while the incus is intact. In such cases, anterior spinotomy can recover mobilization of the malleus, then a prosthesis can be used for the long process of the incus during ossiculoplasty. We conducted stapedectomy with anterior spinotomy on 3 ears in 2 patients. Over 15 dB of hearing was regained in all 3 ears 6 months after surgery. No significant sensorineural hearing loss was seen in any ear. To adapt this surgical procedure, it is necessary to evaluate preoperative CT findings and the status of the ossicular chain during surgery.

Adult↗
PubMed2005

Experimental and clinical studies of malleus fixation.

OBJECTIVES/HYPOTHESIS: Preoperative clinical diagnosis of malleus fixation can be difficult. "Fixation" of the malleus can be caused by various disorders or diseases: fibrous tissue, bony spurs, and neo-osteogenesis around the malleus head or stiffening of the anterior malleal ligament. The conductive hearing loss produced by these disorders or diseases has not been well characterized. The study goals were 1) to determine the effects of various types of malleus fixation using a cadaveric temporal bone preparation and 2) to assess the clinical utility of umbo velocity measurements in preoperative differential diagnosis of malleus fixation and stapes fixation. METHODS: Umbo and stapes velocity were measured in 18 fresh cadaveric human temporal bones with laser vibrometry before and after controlled application of adhesives to the malleus, stapes, or both ossicles. RESULTS: Each simulated pathological condition produced a specific degree of loss in stapes velocity: stiffening of anterior malleal ligament, 0 to 8 dB; fibrous tissue around malleus head, less than 10 dB; bony bar to malleus head, 10 to 30 dB; and extensive neo-osteogenesis around malleus head, greater than 35 dB. Simulated malleus fixations generally produced similar reductions in both umbo and stapes velocity. Stapes fixation reduced stapes velocity with little change in umbo velocity. Because the change in stapes velocity would be similar to conductive hearing loss, experimental results were directly compared with clinical measurements of umbo velocity in surgically confirmed cases of malleus or stapes fixation. The effects of malleus and stapes fixations between the clinical and experimental data were similar. CONCLUSION: The study showed that measurements of umbo velocity and air-bone gap can enable one to diagnose malleus fixation and specifies how to differentiate malleus from stapes fixation.

Aged↗
PubMed1981

Primary malleus fixation: diagnosis and treatment.

Primary malleus fixation occurs in an otherwise normal middle ear without evidence of congenital deformity and without chronic inflammatory changes. It occurs in the latter decades of life and is frequently associated with sensorineural presbycusis. We believe it is a ligament ankylosis with osteoarthritis related to the aging process. The diagnosis of malleus fixation is facilitated through the use of a modified Siegle pneumatic otoscope in conjunction with the Zeiss binocular microscope. The literature pertaining to this subject as well as the more historical reports are reviewed. Goodhill has written extensively on malleus fixation. The audiologic test results in the fixed malleus cases reviewed for this study often presented a misleading picture, sometimes mimicking stapedial otosclerosis with a characteristic Carhart's notch and sometimes indistinguishable from sensorineural presbycusis. Usually speech discrimination scores fell in the very good to excellent range. Weber tests, whether performed by tuning forks or audiometrically, almost always lateralized to the suspect ear. Impedance frequently failed to conform to the expected fixed malleus pattern of low static compliance and absent acoustic reflexes; there was an equal number of low compliance and normal range compliance tympanograms and 15% of the total number of our cases had abnormally high compliance tympanograms. Stapedial reflexes are normally expected to be absent with lateral ossicular fixation, but this was not a consistent finding with contralateral test stimulation. The decision for surgical treatment is dependent on the audiological findings and the potential hearing gain. The technique described consists of the removal of the incus and the head of the malleus and the reconstruction of a sound conducting pathway from the handle of the malleus to the mobile stapes or from the mobile stapes to the under surface of the tympanic membrane using a prosthesis-ossicle arrangement. Malleus fixation occurs far more often than it is diagnosed. Surgical correction can result in a worthwhile hearing gain even when the air-bone gap is narrow or nonexistent. The technique of ossicular reconstruction is dictated by the anatomical findings. Some form of autograft ossicular reconstruction from the malleus handle to the stapes is most frequently utilized. Otosclerosis with stapes fixation sometimes causes a lateral ossicular fixation due to degenerative disease and fibrosis. In this instance a stapedectomy is performed as the primary procedure with subsequent revision as necessary to eliminate the lateral obstruction.

Audiometry↗
PubMed2006

Malleus head fixation: histopathology revisited.

CONCLUSIONS: Malleus head fixation is a rare but not exceptional pathology. It may be apparently congenital or acquired, and can be associated with stapes fixation. In the acquired secondary process two histological types of malleus head fixation were found: the first corresponded to non-tympanosclerotic bone remodeling and the second to localized tympanosclerosis. OBJECTIVE: To describe the histopathologic features of malleus head fixation and to correlate them with its clinical appearance. MATERIAL AND METHODS: Ten patients with surgically proven malleus head fixation were included in this series. A fixed malleus head was resected via a transcanal approach in six patients, and attic bony fragments fixing the malleus head were removed via a mastoidectomy without disruption of the ossicular chain in four. Histopathologic studies were performed for both types of malleus head fixation. RESULTS: Three types of acquired malleus head fixation were defined in accordance with the surgical and histopathological findings. Histologically, the first type presented with normal bone tissue, the second was characterized by non-tympanosclerotic bone remodeling and the third presented with a localized tympanosclerotic focus in the tympanic cavity.

Adolescent↗
PubMed2004

Response of the cat eardrum to static pressures: mobile versus immobile malleus.

A phase-shift shadow moiré interferometer was used to measure the shape of the cat eardrum with a normal mobile malleus and with an immobile malleus as it was cyclically loaded with static middle-ear pressures up to +/-2.2 kPa. The shape was monitored throughout the loading and unloading phases, and three complete cycles were observed. The mobile-manubrium measurements were made in five ears. In three ears, the malleus was then immobilized with a drop of glue placed on the head of the malleus. Eardrum displacements were calculated by subtracting shape images pixel by pixel. The measurements are presented in the form of gray-level full-field shape and displacement images, of displacement profiles, and of pressure-displacement curves for selected points. Displacement patterns with a mobile malleus show that pars-tensa displacements are larger than manubrial displacements, with the maximum pars-tensa displacement occurring in the posterior region in all cats except one. Displacements vary from cycle to cycle and display hysteresis. For both the mobile-malleus and immobile-malleus cases, the eardrum response is nonlinear. The response is asymmetric, with lateral displacements being larger than medial displacements. With a mobile malleus, manubrial displacements exhibit more pronounced asymmetry than do pars-tensa displacements.

Algorithms↗
PubMed2002

The use of malleus allografts in ossiculoplasty.

OBJECTIVE: To assess the functional performance of remodeled malleus allografts in a malleus-footplate assembly in terms of hearing results and mid long-term stability. STUDY DESIGN: A retrospective study of 60 consecutive patients who underwent a malleus allograft ossiculoplasty from 1993 until 2000. In all cases the incus and the stapedial arch were missing as the result of cholesteatoma (49), chronic otitis (5), incus necrosis resulting from stapes prosthesis (5), and congenital ossicular malformations (1). In all cases malleus allografts were remodeled to form a malleus-stapes assembly. RESULTS: The audiometric results, using such an ossiculoplasty, revealed an overall median gain of 18.3 dB at 2 months, 22.3 dB at 6 months, and 25 dB 1 year postoperatively on Fletcher frequencies. An air-bone gap closure within 20 dB was achieved in 81% of all cases 1 year postoperatively. No cases of extrusion have been seen in our series. CONCLUSION: Our findings suggest that malleus allografts are capable of generating good and stable functional results as malleus-stapes assembly.

Adolescent↗
PubMed2004

Comparison of the mechanical performance of ossiculoplasty using a prosthetic malleus-to-stapes head with a tympanic membrane-to-stapes head assembly in a human cadaveric middle ear model.

HYPOTHESIS: Ossiculoplasty using prosthetic reconstruction with a malleus assembly to the stapes head will result in better transmission of vibrations from the eardrum to the stapes footplate than reconstruction with a tympanic membrane assembly to the stapes head. Both types of reconstruction will be affected by tension of the prosthesis. BACKGROUND: Theories (and some clinical studies) that the shape of the normal tympanic membrane is important suggest that prosthetic reconstruction to the malleus performs better than reconstruction to the tympanic membrane. This has not been previously tested by directly measuring vibration responses in the human ear. Our previous work suggests that tympanic membrane assembly to the stapes head type prostheses performed best under low tension. This had not been previously tested for malleus assembly to the stapes head type prostheses. METHODS: Hydroxyapatite prostheses were used to reconstruct a missing incus defect in a fresh cadaveric human ear model. Two types of prostheses were used, one from the stapes head to the malleus (malleus assembly to the stapes head), the other from the stapes head to the tympanic membrane (tympanic membrane assembly to the stapes head). Stapes footplate center responses were measured using a laser Doppler vibrometer in response to calibrated acoustic frequency sweeps. RESULTS: Tension had a very significant effect on both types of prostheses in the lower frequencies. Loose tension was best overall. The malleus assembly to the stapes head type prostheses consistently performed better than the tympanic membrane assembly to the stapes head type prostheses when stratified for tension. CONCLUSION: Tension has a significant effect on prosthesis function. Malleus assembly to the stapes head type prostheses generally result in better transmission of vibrations to the stapes footplate than tympanic membrane assembly to the stapes head type prostheses.

Biomechanical Phenomena↗
PubMed2003

The discomallear ligament and the anterior ligament of malleus: an anatomic study in human adults and fetuses.

According to some reports, movement of the malleus, resulting from anterior hypertension on the discomallear ligament (DML), could produce aural symptoms related with damage to middle ear structures. The aim of this study was to examine the topographic relationship of the DML and the anterior ligament of malleus (ALM). Four fetuses and 16 adult hemi-sectioned heads were used to determine the anatomic-clinical relevance of DML and ALM in temporomandibular disorder. In fetal specimens, the DML was distinctly interposed between the malleus and the disc of the temporomandibular joint (TMJ), and the ALM had a structure apparently composed of the superior and inferior lamellae, running anteriorly in continuation with the sphenomandibular ligament (SML) through the future petrotympanic fissure (PTF). In all adult specimens, the DML was inserted into the malleus, and it expanded broadly toward the disc and capsular region of the TMJ in a triangular shape and inserted into the disc and capsule of the TMJ. The two-lamellae structure of the ALM was not distinguishable in adult specimens. The overstretched ALM resulted in movement of the malleus in five cases, but similar tension applied to the DML did not cause any movement of the malleus. This result provides an indication of the clinical significance of the ALM, a ligamentous structure continuous with the SML. It is apparent that the ALM has the potential to cause aural symptoms as a result of damage to the middle ear structure.

Adult↗
PubMed1976

Epitympanic malleus fixation: correction without disrupting the ossicular chain.

The preoperative diagnosis of malleus fixation can be made consistently with a pneumatic otoscope. Nontympanosclerotic epitympanic malleus fixation, for the most part, has been corrected by disrupting the ossicular chain and then reconstructing the sound-conducting mechanism. Once the diagnosis of malleus fixation is established, the surgical approach should be modified to cope with the fixed malleus. A wide, inferiorly based tympanotomy flap affords ample access to the epitympanum and permits definitive resolution of the associated conductive hearing loss. Atticotomy and discreet osteotomy can free the fixed malleus and preserve continuity of the osscular chain in over 90 percent of the patients with this syndrome. Experience for 46 patients having bony epitympanic malleus fixation, both congenital and acquired, was examined in concluding that the anatomical continuity of the ossicular chain can and should be maintained in most patients. The residual air-bone gap is less with an intact, though modified, ossicular chain than it is with a chain that has been reconstructed.

Aged↗
PubMed1999

Malleus-handle fracture: historical review and three new cases.

OBJECTIVE: Isolated malleus-handle fracture is a clinical entity seldom reported in the medical literature but well known in the last century. The purpose of this paper was to review the literature over the last 150 years and describe three new cases. STUDY DESIGN: Extensive review of the literature and chart review of three patients with isolated malleus-handle fracture. SETTING: The study was performed partly at a private practice and partly in an academic tertiary referral center. PATIENTS: At least 43 malleus-handle fractures have been reported in the literature. Three new occurrences were studied. RESULTS: The review of the literature showed that head trauma with skull base fracture was the most frequent cause of malleus-handle fracture, followed by blows on the tympanic membrane and barotrauma, penetration of pen-holders or hair pins, penetration of twigs, and attempts to remove a foreign body pushed inside the ear. In the first patient reported here, the malleus-handle fracture was caused by a whirlpool bath, in the second, the cause was unknown, and, in the third, it was caused by a brisk decompression inside the ear canal. CONCLUSIONS: This lesion is not rare, and the diagnosis frequently is missed because the tympanic membrane appears intact. A careful otoscopic examination with pneumomassage, an abnormally high compliance at tympanometry, and a carefully recorded medical history may lead to the diagnosis of isolated malleus-handle fracture in a patient with a mild conductive hearing loss.

Acoustic Impedance Tests↗
PubMed1999

Malleus-to-footplate prosthetic interposition: experience with 265 patients.

Absence of the long process of the incus with or without absence of the stapes head accounts for more than 80% of ossicular discontinuities. Total or partial replacement prostheses, made of various materials, are interposed to restore the transfer function of the middle ear. To simplify ossicular reconstruction, reduce operative times and costs, improve functional outcomes, and avoid the risk of infections, we have adopted, during the past 10 years, a technique that makes use of a personally designed alloplastic prosthetic device. The prosthesis connects the malleus to the footplate, even in the presence of the stapes superstructure. This malleus-to-footplate prosthesis consists in a plastipore-coated steel piston and hydroxyapatite head, complete with a groove. The groove is placed beneath the malleus neck after dissection of the tensor tympani tendon and the shaft of the piston on the footplate. Two hundred ninety primary ossiculoplasties with the malleus-to-footplate prostheses were performed in 265 patients from 1986 to 1995 in the ENT Department of the University of Verona. The average postoperative air-bone gap at 0.5 to 3 kHz was 11 dB at 1 year and 14 dB at 5 years. These outcomes are significantly better than those personally obtained previously with ossicular or alloplastic prostheses. No extrusions occurred. The structural characteristics of the malleus-to-foot-plate prosthesis endow the prosthesis with a high degree of biocompatibility and stability and optimal sound-transfer function. The rationale for this particular ossiculoplasty procedure is discussed.

Adolescent↗
PubMed2005

Malleus-to-footplate ossicular reconstruction prosthesis positioning: cochleovestibular pressure optimization.

AIMS: To determine 1) the best position for hydroxylapatite malleus-to-footplate (MFP), ossicular replacement prosthesis (ORP) in reconstructed ears, and 2) whether preserving the stapes superstructure (SS), when present, has acoustic advantages. BACKGROUND: Positioning of the MFP-ORP head beneath the neck of the malleus may produce maximal force, whereas positioning beneath the manubrium of the malleus may produce the greatest displacement. It is not clear which is the optimal placement position. In addition, we look at the effect of the SS on sound transmission to the inner ear in ossicular reconstruction. METHODS: The ear-canal air pressure and vestibular hydro-pressure were measured in human cadaver temporal bones with incus intact, removed, and replaced with the MFP-ORP; the ORP head was placed at three different positions on the malleus (head, mid-manubrium, and umbo) while keeping its base at the center of stapes footplate with intact or removed stapes SS. The vestibular pressure ratio between the ear with intact incus and MFP-ORP reconstructed ear is defined as Lmfp, the loss caused by the prosthesis in relation to the normal ossicular chain. RESULTS: The mean magnitude of Lmfp, averaged in the important speech frequency region of 0.5 to 3 kHz, is approximately 7.8 dB at the neck with stapes SS. In comparison, mean magnitude of Lmfp for mid-manubrium without stapes SS is 15 dB (p = 0.04), and with the stapes SS it is 16 dB (p = 0.05), whereas at the umbo without SS it is 15 dB (p = 0.03). In the 8 kHz region, the mean magnitude of Lmfp is approximately 1 dB with the stapes SS intact and approximately 8.5 dB when it was removed (p < 0.09). CONCLUSION: There are significant physiologic advantages to placing the hydroxylapatite MFP-ORP beneath the neck of the malleus and preserving the SS.

Aged↗
PubMedDate not supplied

Human tympanic membrane--malleus attachment. Preliminary study.

The relationship between the malleus handle and the tympanic membrane in humans has been studied with primary attention being directed to the fibrous layer of the tympanic membrane and its method of attachment to the malleus. This attachment is most intimate at the level of the umbo and becomes progressively more tenuous as the short process is approached. The long process of the malleus, comprised of a bony core, has a definite sleeve of cartilage surrounding its entire length. This cartilage is surrounded by a perichondrial layer which has previously been termed a periosteum. In the lower third, the fibrous lamina propria appears to split equally and the fibers then blend imperceptively with those of the perichondrial layer surrounding the manubrium. At high levels, the attachment is less intimate, most of the fibers appearing to pass lateral to the malleus handle. The embryologic development of the tympanic membrane-malleus junction has been considered and the anatomical features of this area have been considered in relation to functional requirements.

Ear Ossicles↗
PubMed1985

Structures and relationships of the anterior malleus ligament.

48 temporal bones, fixed in 10 percent formaline, were dissected by microdissection and the anterior malleus ligament was studied morphological and histologically. Some gross sections were made to microscopic observations and microssections, to histologic preparations. The anterior malleus ligament shows fasciculate aspect in its intratympanic portion, by 3 fascicles , superior, middle and inferior, with dentate form. The superior fascicle is whitish, dimmed and frequently thinner than the others and was classified under 4 patterns, according to its insertion. The middle fascicle is the thickest, voluminous+, whitish and shinning ; tendinous, it is inserted below the superior fascicle . The inferior fascicle is thickness and insert immediately under the middle one. The extratympanic portion of the anterior malleus ligament is fasciculate but little evident; it shows irregular aspect, flattened, with disperses fibres into the petrotympanic fissure. However can be noted continuity of the fascicles that are crossed by the nerve chorda tympani. Several fibres insert on the nasal spine and on the sphenomandibular ligament, where the fibres intertwine. They finish on the disc, articular capsule and anterior malleus ligament through a true interlinked. Histological observations of the anterior malleus ligament show a modelate and dense conjunctive formation, while in the temporomandibular joint capsular region was not a modelate conjunctive.

Decalcification Technique↗