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At least 91 records · Page 5Linked to original sources
PubMed2003

Ectopic stapes: a case report with embryologic correlations.

A case report of unilateral congenital stapes misplacement revealed by computed tomography is presented. In addition to this malformation, the malleus was synostosed to the middle ear roof. This kind of stapes ectopia has not been described previously. We have analyzed the malformative pattern in the light of normal and teratologic development of the stapes. In a teratologic model in which retinoic acid is administered to pregnant mice, we have observed an ectopic stapes primordium independent of the otic capsule. We discuss the possible pathogenesis of this abnormality in terms of the genetic events of middle ear development, which can be perturbed by retinoic acid administration.

Adult↗
PubMed1999

Isolated congenital stapes suprastructure fixation.

Isolated congenital anomalies of the ossicles are rare. The majority of cases of congenital conductive hearing loss secondary to middle-ear anomalies have other associated defects, such as atresia, microtia and craniofacial deformities. We present a rare case of isolated congenital stapes suprastructure fixation, where a monocrural stapes with a mobile footplate was attached to the promontory by bony synostosis. There was no stapedius muscle nor pyramidal process. The incus and malleus were of normal configuration. Mobilization of the stapes from the promontory resulted in improvement in hearing. We believe this is the first reported case of such an abnormality. A review of the world literature of isolated stapes suprastructure ankylosis and the classifications of minor congenital anomalies are discussed.

Adult↗
PubMed2006

Tympanosclerosis involving the ossicular chain: mobility of the stapes in association with hearing results.

CONCLUSION: The preoperative bone conduction level provides not only prognostic information but also information on the mobility of the stapes in tympanosclerosis. The surgical results depend upon the stapes mobility. OBJECTIVES: We aimed to evaluate operative findings and hearing results of tympanosclerosis involving the ossicular chain, in order to understand the pathophysiology and to establish better surgical treatment of tympanosclerosis. PATIENTS AND METHODS: Between January 1998 and March 2004, 29 patients (29 ears) with tympanosclerosis involving the ossicular chain underwent tympanoplasty at our hospital. Patients with myringosclerosis only, or with an associated cholesteatoma, were excluded from this study. The clinical and operational records and pre- and postoperative pure tone audiograms were reviewed retrospectively. RESULTS: Intact canal wall tympanoplasty was applied to all 29 patients. A non-staged operation was performed on 21 patients, and a staged operation was performed on the remaining 8 patients. In 25 patients (86.2%), the sclerotic lesion of the ossicles was located in the epitympanum. In the remaining four, the sclerotic lamella coated only the ossicular chain. On average, the preoperative air conduction hearing level of 57.9 dB was significantly improved to 46.3 dB after tympanoplasty. The success rate of middle ear surgery was 65.5% (19 of 29 patients), according to the criteria of the Otological Society of Japan. In 16 patients (55.2%), the mobility of the stapes was preserved (group A), while in the remaining 13 patients (44.8%), the stapes was fixed (group B). The mean preoperative bone conduction of 25.5 dB in group A was significantly better than that of 37.2 dB in group B. The hearing result significantly improved in group A but not in group B. The success rates were 75% (12 of 16 patients) in group A and 53.8% (7 of 13 patients) in group B.

Adolescent↗
PubMed2005

Codetection of measles virus and tumor necrosis factor-alpha mRNA in otosclerotic stapes footplates.

HYPOTHESIS: Otosclerosis is a disease of unknown etiology causing conductive or sensorineural hearing loss. Persistent measles virus infection of the otic capsule is considered to be one of the etiologic factors in otosclerosis. BACKGROUND: Determinants of measles virus infection and reactive inflammation were studied in otosclerosis. The presence of measles virus was shown in otosclerotic patients by reverse-transcription polymerase chain reaction (RT-PCR) amplification of the viral RNA. No report is available, however, on the types and features of paracrine cytokines in otosclerosis. METHODS: Nucleic acid was extracted from stapes footplate samples of clinically otosclerotic patients. Measles virus nucleoprotein RNA was amplified by seminested RT-PCR. Tumor necrosis factor (TNF)-alpha mRNA expression was detected by RT-PCR in otosclerotic bone and was correlated with preoperative audiologic findings and measles virus positivity. RESULTS: Among 154 clinically otosclerotic patients, 99 stapes footplate specimens contained measles virus RNA. TNF-alpha mRNA was detectable in 88 virus-positive and in 6 virus-negative stapes footplates. There was no detectable TNF-alpha mRNA expression in virus negative cases. CONCLUSION: The etiologic role of measles virus in the pathogenesis of otosclerosis should be considered. Detection of TNF-alpha mRNA demonstrates activated osteoclast functions and inflammatory pathways in otosclerotic stapes footplates associated with measles virus presence. Virus-associated and virus-negative pathomechanisms of otosclerosis should be distinguished.

Adult↗
PubMed2006

Congenital stapes ankylosis: study of 28 cases and surgical results.

OBJECTIVE: The objective of this study was to analyze functional results after stapes surgery in patients with congenital nonprogressive conductive deafness resulting from an isolated fixation of the stapes according to age and surgical procedure. STUDY DESIGN: The authors conducted a retrospective case series from March 1993 to December 2003 in patients from two tertiary referral centers. METHODS: Twenty-eight patients were operated on by stapedotomy or partial stapedectomy using Teflon stapes prostheses. The median age at surgery was 14.2 years (range, 8.3-29.1 years). Main outcome measures were clinical and audiometric evaluation before and after surgery. Mean air conduction (MAC) and bone conduction (MBC) thresholds were recorded at 0.5, 1, 2, and 4 kHz. The evaluation of functional outcome was based on the MAC gain, the MBC comparison, and the mean postoperative and residual air-bone gaps. RESULTS: The median preoperative MAC was 50 dB (range, 19.0-65.0 dB) with a 35.0 dB median dB air-bone gap. With a mean follow up of 19 months, postoperative hearing improvement was statistically significant: median gain of 32.5 dB (P<.001) and median residual air-bone gap of 3.5 dB. The MBC was also statistically improved with median pre- and postoperative MBC of 11.5 and 6.5 dB, respectively (P<.001). Results were not dependent on the age group or type of surgery (stapedotomy or partial stapedectomy). No perceptive hearing loss was observed despite one gusher case. CONCLUSION: Surgical treatment of isolated congenital stapes ankylosis allows good functional results regardless of age or type of surgery.

Adolescent↗
PubMed1984

Histopathology of the stapes in otosclerosis.

A histopathological examination was made of 60 stapes obtained during surgery for clinical otosclerosis. The findings, correlated with the clinical history and macroscopic appearances of the stapes, led to the following observations. The histological extent of the focus of otosclerosis agrees well with the macroscopic appearance of the footplate lesion seen under the operating microscope. The earlier the age of onset of hearing loss the greater the probability of active, severe and diffuse otosclerotic involvement of the footplate. Two-thirds of the cases with diffuse and severe footplate otosclerosis had signs of active disease. A late age of onset of clinical otosclerosis tends to be associated with lesions that are limited to the anterior pole of the stapes footplate. Active otosclerosis is rare in these cases. The case for macroscopic increase in extent of the lesion with time could not be established by the data. The evidence supports the view that the severity and extent of otosclerotic disease in the footplate is determined more by age at onset than by duration of symptoms. Healing of the active focus of otosclerosis may not always occur despite a long duration of symptoms. A highly active focus in the stapes footplate can remain active for many years.

Ear Ossicles↗
PubMed1999

[The choice of the stapes surgical style in treatments of the otosclerosis].

OBJECTIVE: To investigate the effects of the stapes surgery on treatment of the otosclerosis to find out the more suitable surgical style. METHOD: 71 cases including 31 cases with stapes lifting surgery, 34 cases with partial stapcdectomy, 6 cases with total stapedectomy were summed. RESULT: Both the stapes lifting surgery and partial stapedectomy have steady effects on hearing level for a short or long time. CONCLUSION: The stapes lifting surgery should be adopted as the first surgical style for it is easier and the vestibular reaction is slighter. It will not affect the following surgical process even the two crura are broken.

Adult↗
PubMed1978

[Anomalies of the stapes (author's transl)].

Reported are four cases of anomalies of the stapes and the oval window niche. Their diagnostic and operative problems are discussed. The report includes one case of spontaneous cerebrospinal otorrhea. Surgical exploration of the middle ear demonstrated a fluid leak from a fistula in the stapes footplate. Two cases presented combined congenital anomalies of the stapes and facial nerve as a cause of hearing loss. Additionally one case of "columella" shaped stapes was observed. The embryological aspects of the middle ear structures are discussed.

Adult↗
PubMed1995

[Stapedectomy in congenital stapes fixation].

Because several cases of cerebral-spinal fluid leakage (perilymph gushers) have been reported during stapedectomy for congenitally fixed stapes in children, many otologists advise against surgical intervention. The pathophysiologic mechanism of the gusher and its association with a congenitally fixed stapes is, however, poorly understood. This study was designed to examine the pre-operative presentation and hearing results of 10 children undergoing stapedectomies for congenital fixation. No perilymph gushers of significant sensorineural hearing loss was encountered. All but one case resulted in closure of the air-bone gap and speech frequencies to within 20 dB. The average air-bone gap was 11.2 dB. Minor congenital abnormalities of the stapes suprastructure were seen in 3 cases. Review of case reports in the literature indicate that gushers in association with surgical manipulation of the congenitally-fixed stapes occur almost exclusively in males and that pathophysiology involves a defect in the internal auditory canal (as opposed to a patent cochlear aqueduct). A pre-existing sensorineural hearing loss may also be a risk factor for perilymph gusher.

Adolescent↗
PubMed1995

[Revision of the stapes foot plate with various laser systems. 1: Continuous laser irradiation].

During stapedotomy, the small dimensions and highly sensitive anatomic structures present require the highest degree of precision and safety. The risk of damage to middle and inner ear structures through manipulation with conventional instruments can be reduced by non-contact perforation of the footplate with the laser beam. The present study was devised to clarify which of the presently available laser systems was best suited for use in stapes surgery and thus represent a significant alternative to conventional stapedotomy. Isolated human stapes and bovine compact-bone platelets were used to investigate the connections between the parameters of various laser systems and their effects on bone tissue. The aim was to optimize the laser parameters required to achieve a perforation of 500 microns to 600 microns in diameter. In addition, the thermal effects of laser irradiation were assessed. Three different systems were employed: the argon and CO2 lasers in continuous wave (cw) modes and the CO2 laser in superpulse mode. The lasers investigated offered the advantage of achieving an adequately large perforation with one or a few juxtaposed applications but caused in part extensive thermal side effects at the stapes footplate. To reduce thermal effects, footplate perforation was best performed by several juxtaposed single shots at low power, short pulse duration and small beam diameter. The suitability of the argon laser for stapedotomy was rendered doubtful in view of the lower absorption coefficient of the stapes for the argon laser beam and the considerable influence exerted by the degree of pigmentation of the irradiated tissue sites with a resultant poor reproducibility of the perforation diameter.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1995

[Modifying the stapes footplate with various laser systems. II. The pulsed laser].

The object of the present study was to examine the tissue ablation capacity of various pulsed lasers at the stapes footplate. Isolated human stapes and bovine compact-bone platelets (thickness 90 microns) were used to determine effective laser parameters for achieving a perforation measuring 500 microns to 600 microns in diameter. Apart from achieving the perforation diameters, particular attention was given to the form and quality of the perforations, reproducibility of the perforation effect and the thermally altered border zones occurring at the footplate. Four pulsed laser systems were used: excimer, Ho:YAG, Er:YSGG and CO2 lasers. An adequately large perforation generally could only be achieved by several repeated shots at the same application site, since only a small amount of tissue was ablated per application. The mechanism of the photoablation caused the extent of the thermal side effects to be markedly lower than with the continuous wave (cw) and superpulse systems. For this reason and because of their highly reproducible perforation effect, they were basically better suited for stapedotomy than the cw systems. It was possible, however, that as a result of the longer application time and the need to repeatedly irradiate the same application site, the higher pulse counts could prove to be disadvantageous in clinical practice. Among the pulsed laser systems, the Er:YSGG laser had the highest ablation rate at the stapes and was thus the most effective laser for interventions at the footplate. Although somewhat less effective than the Er:YSGG laser in our studies, the Ho:YAG and pulsed CO2 lasers also appear to be suitable for stapes surgery. On the other hand, we did not consider the excimer laser (308 nm) to be particularly effective at the footplate because of its low ablation rates.

Animals↗
PubMed1996

Sex-related differences in composition of otosclerotic and unafflicted stapes.

This research was undertaken to determine whether stapedial composition could be used to distinguish the sex of patients afflicted with otosclerosis and the sex of unafflicted controls. Energy dispersive-electron probe microanalyses (EDS/EPMA) of otosclerotic stapes from 10 male and 13 female patients were compared with analyses from four unafflicted men and five women. The composition of control stapes differed at p << 0.05 (discriminant analyses) from otosclerotic specimens. Thirteen elements analyzed are in two statistical categories: Group I: Ca, Cr, Fe, Zn, Mg, P, and S; and Group II: Al, K, Mn, Na, Si, and Ti. Elements of Group I distinguish unafflicted men from unafflicted women at a high level of significance (p << 0.05). The same group distinguished afflicted men from otosclerotic women at a lower level (p < or = 0.05), but only if comparisons are based on the single (rather than mean) maximum value of each trace element in each stapes, and only if both Cr and Zn are included in the group. Group I elements also distinguish control versus afflicted men and control versus afflicted women at p << 0.05. Group II elements do not distinguish any of the cohorts mentioned at p < or = 0.05, although they do more successfully classify control and afflicted women as to sex than they do men. They also more successfully predict the diseased status of afflicted men and women than the normal status of controls. The elements whose concentrations exhibit sex-related convergence in otosclerotic stapes are either fundamental constituents of stapedial hydroxyapatite in general or are specific activators of enzymes implicated in otosclerosis. Thus further investigation of the role of metal-potentiated enzymes in the origin of the disorder is warranted.

Female↗
PubMed1996

Stapes fixation associated with symphalangia.

We describe a 10-year-old boy and his 9-year-old sister, both of whom had bilateral hearing loss associated with ankylosis of the proximal interphalangeal joints (symphalangia). They had no other abnormal findings except hearing loss and ankylosis of the joints of some fingers and toes on systemic examination. The cause of conductive hearing loss in both cases was bony fusion between the stapes and the bone of the oval window niche. There were no other anatomical abnormalities in the middle or the external ear. The patients' hearing improved markedly after stapes surgery. Histopathologic examination of the stapes revealed an abnormal zone of ossification near the anterior annular ligament and calcification in the annular ligament, which seemed to be the cause of the stapes fixation.

Child↗
PubMed1977

[On the oscillation form of the stapes as a function of the volume. Experimental investigations into the human temproal bone preparation (author's transl)].

In order to further clarify the change in the oscillation form of the stapes as a function of the volume, measurements were performed in 10 fresh temporal bone preparations at two points at the short and long diameters of the base of the stapes from the labyrinthine side. The oscillations were recorded from two channels, first, by two electro-dynqual stress on the base of the stapes, also optically by modulating a light beam and electronically scanning by means of a phototransistor, and the oscillations were then recorded on a two-beam oscilloscope. The result was that it is not possible to prove any phase shift between the two measurement points at the short or at the long base of the stapes in a volume range within the physiological limits. Thus, any sweep phenomenon at high volumes does not exist. Also, a volume-dependent shift of the oscillation axis on a line within the base was not to be observed.

Ear Ossicles↗
PubMed2006

An unusual stapes.

We present a case of a highly unusual stapes in the presence of a normal external ear. The stapes exhibits rudimentary anterior crus with abnormally shaped posterior crus that attached to the mid-portion of a fixed, rudimentary footplate. To our knowledge, this anomaly has not been previously documented. We review the embryological cause that may be contributing to the development of this congenitally abnormal stapes superstructure. This is to highlight the importance of the knowledge of the anatomy of the stapes and its variations especially to the otologists.

Adolescent↗
PubMed2001

Transient evoked and distortion product otoacoustic emissions following successful stapes surgery.

BACKGROUND: The effect of stapes surgery on the recording of otoacoustic emissions is unknown. The aim of the present study was to evaluate the success of stapes surgery by using acoustically evoked otoacoustic emissions as an objective and fast method for postoperative hearing evaluation. METHODS: Transient evoked (TEOAE) and distortion product otoacoustic emissions (DPOAE) were measured consecutively in otosclerosis patients before as well as 3 and 6 months after stapes surgery. RESULTS: Air-bone gaps in the pure-tone audiograms were significantly reduced in all patients. TEOAEs and DPOAEs were not measurable preoperatively and were only evident in one patient postoperatively with low amplitudes in a narrow frequency range. CONCLUSIONS: Despite a subjective hearing improvement and a significant reduction of the conductive loss, otoacoustic emissions are only rarely evident after successful stapes surgery.

Acoustic Impedance Tests↗
PubMed1985

Histopathology of the stapes in osteogenesis imperfecta.

Conventional histological studies of stapes footplates from patients with osteogenesis imperfecta revealed, in nine out of 15 stapes examined, an otospongiotic-like lesion. Although the morphology of the stapedial lesion was comparable to the early otosclerotic focus, a greater structural disorganization and larger resorption spaces in osteogenesis imperfecta distinguished the two conditions. The histopathology of the stapes was related to the morphology of cortical and trabecular bone from the iliac crest. Various degrees of immature, osteogenic bony tissue were found in the iliac crest, showing no resemblance to the otospongiotic-like focus in the footplate. Even though the histologic appearance of the stapes footplates differed from the findings in peripheral bone, the present study indicates that the stapedial lesion in osteogenesis imperfecta is most likely a manifestation of the generalized bone and connective tissue disorder. The study further supports the view that osteogenesis imperfecta and otosclerosis are of different aetiology.

Adolescent↗
PubMed2002

Osteoblast-like cell cultures from human stapes.

OBJECTIVE: In order to develop new middle ear prostheses for ossicular reconstruction it is important to study how the recipient middle ear tissues, especially the stapes footplate and superstructure, react to the implanted biomaterial. In this respect, animal studies and cell cultures using non-specific cells are of limited value. MATERIAL AND METHODS: The morphology and growth pattern of cells cultured from human stapes were studied. Cultured cells were examined for the presence of alkaline phosphatase and were processed for immunocytochemistry in order to detect the presence of osteocalcine. Fibroblast cultures served as controls. RESULTS: Cultured stapes cells proliferated in a polygonal-cubic shape and without any regular pattern in the culture. These cells were shown to contain alkaline phosphatase and osteocalcine. Cultured fascia fibroblasts proliferated in a spindle-shaped form and in a pattern resembling a shoal of fish. Cultured fibroblasts did not contain alkaline phosphatase or osteocalcine. CONCLUSIONS: It is possible to culture osteoblasts from human stapes. These cells can be characterized as osteoblast-like cells by means of their external shape and the presence of alkaline phosphatase and osteocalcine. Using these cultures, specific in vitro investigations concerning the interaction of biomaterials and middle ear ossicles could be performed.

Alkaline Phosphatase↗