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B-ENT 2016Middle ear damages. The eardrum and middle ear are often exposed to blunt and penetrating trauma, blasts, thermal or caustic injuries. These injuries may result in... (Review)
Review
Middle ear damages. The eardrum and middle ear are often exposed to blunt and penetrating trauma, blasts, thermal or caustic injuries. These injuries may result in tympanic membrane perforation, middle ear haemorrhage, dislocation and fracture of the ossicular chain, perilymphatic fistula and damage to the chorda tympani and/or facial nerve. In case of life-threatening injuries and/or mass casualty incidents, middle ear trauma obviously does not take highest priority. However, middle ear lesions should be suspected and recognized as early as possible. After meticulous history taking, physical examination consists of cranial nerve evaluation, thorough inspection of the outer ear, otoscopy and assessment of hearing and vestibular function. In the majority of cases, traumatic tympanic membrane perforations by penetrating and blunt injuries have a good prognosis with spontaneous resolution. Tympanic membrane perforations from blast trauma, thermal or caustic injuries are less likely to heal spontaneously. Perforations lasting six months after injury warrant surgery. A high resolution CT scan of the temporal bone is required in case of immediate complete facial nerve paralysis and when oval window pathology or perilymphatic fistula is suspected. Early surgical intervention is needed in case of early onset facial nerve paralysis, when there is suspicion of a perilymphatic fistula with persisting or increasing vestibular symptoms or neurosensory hearing loss and in case of vestibular dislocation of the stapes footplate. When ossicular chain damage is suspected, elective tympanoplasty is indicated. As any traumatic tympanic membrane perforation runs the risk of cholesteatoma formation, biannual follow-up during a minimum of two years is recommended.
Topics: Aftercare; Blast Injuries; Ear, Middle; Humans; Otoscopy; Tomography, X-Ray Computed; Tympanic Membrane Perforation; Tympanoplasty; Wounds, Penetrating
PubMed: 29461741
DOI: No ID Found -
Otolaryngologic Clinics of North America Feb 2021Middle ear anatomy and physiology is highly complex, yet familiarity is important to perform middle ear surgery and understand surgically relevant ventilation pathways... (Review)
Review
Middle ear anatomy and physiology is highly complex, yet familiarity is important to perform middle ear surgery and understand surgically relevant ventilation pathways of the ear compartments. The middle ear is divided into five subspaces: the mesotympanum, the retrotympanum posteriorly, the epitympanum superiorly, the protympanum anteriorly, and the hypotympanum inferiorly. The Eustachian tube plays a crucial role in maintaining middle ear aeration and atmospheric pressure. There are two independent aeration routes of the epitympanum. Thanks to the advent of the endoscope, this anatomic and physiologic knowledge has allowed one to understand the pathophysiology of ear diseases, improving surgical concepts.
Topics: Ear, Middle; Endoscopy; Humans; Middle Ear Ventilation; Otoscopy; Treatment Outcome
PubMed: 33153736
DOI: 10.1016/j.otc.2020.09.003 -
Revue de Laryngologie - Otologie -... 1999The middle ear forms part of the sound transformer mechanism, together with the outer ear and the conducting system of the inner ear. An intermediate sensory organ,... (Review)
Review
The middle ear forms part of the sound transformer mechanism, together with the outer ear and the conducting system of the inner ear. An intermediate sensory organ, sensitive to acoustic vibration, and linked to the inner ear, the middle ear made its appearance during the period of adaptation of marine creatures to a terrestrial habitat; its presence is therefore a phylogenetic requirement. It is classical to ascribe three functions to the middle ear: the transmission of acoustic vibrations from the tympanic membrane to the cochlea, impedance matching between the air in the external auditary meatus and the labyrinthine fluids, and protection of the inner ear by means of the acoustic reflex. If the classical mechanical explanation has been able to explain its function, the conceptualization of its physiology in terms of energy allows an even better understanding, as well as providing and explanation for the paradoxes which arise in clinical practice when the classical model is used.
Topics: Ear, Middle; Humans; Reflex, Acoustic
PubMed: 10769562
DOI: No ID Found -
Acta Otorrinolaringologica Espanola Apr 1998Middle-ear cancer represents 5 to 10% of all ear neoplasms. Risk factors include chronic suppurative pathology of the middle ear and prior irradiation. Most malignant... (Review)
Review
Middle-ear cancer represents 5 to 10% of all ear neoplasms. Risk factors include chronic suppurative pathology of the middle ear and prior irradiation. Most malignant tumors are squamous-cell carcinomas. We report the case of a 51-year-old woman with this process. The ideal treatment is mastoidectomy or pterosectomy followed by radiotherapy. We made a bibliographic review of the clinical manifestations, diagnosis, treatment, and prognosis of middle-ear cancer. Five-year survival rates range from 25 to 50% in patients who undergo surgery and radiotherapy.
Topics: Carcinoma, Squamous Cell; Chronic Disease; Ear Neoplasms; Ear, Middle; Female; Humans; Middle Aged; Prognosis; Risk Factors; Tomography, X-Ray Computed
PubMed: 9644865
DOI: No ID Found -
Scientific American Aug 1989
Review
Topics: Animals; Auditory Perception; Ear, Middle; Electromyography; Humans; Muscle Contraction; Reflex; Voice
PubMed: 2667133
DOI: 10.1038/scientificamerican0889-74 -
Hearing Research Jul 2019
Topics: Animals; Biomedical Research; Diffusion of Innovation; Ear, Middle; Humans; Otolaryngology; Otologic Surgical Procedures
PubMed: 30914231
DOI: 10.1016/j.heares.2019.03.008 -
Hearing Research Mar 2023The three-bone flexible ossicular chain in mammals may allow independent alterations of middle-ear (ME) sound transmission via its two attached muscles, for both... (Review)
Review
The three-bone flexible ossicular chain in mammals may allow independent alterations of middle-ear (ME) sound transmission via its two attached muscles, for both acoustic and non-acoustic stimuli. The tensor tympani (TT) muscle, which has its insertion on the malleus neck, is thought to increase tension of the tympanic membrane (TM). The stapedius (St) muscle, which has its insertion on the stapes posterior crus, is known to stiffen the stapes annular ligament. We produced ME changes in human cadaveric temporal bones by statically pulling on the TT and St muscles. The 3D static TM shape and sound-induced umbo motions from 20 Hz to 10 kHz were measured with optical coherence tomography (OCT); stapes motion was measured using laser-Doppler vibrometry (LDV). TT pulls made the TM shape more conical and moved the umbo medially, while St pulls moved the umbo laterally. In response to sound below about 1 kHz, stapes-velocity magnitudes generally decreased by about 10 dB due to TT pulls and 5 dB due to St pulls. In the 250 to 500 Hz region, the group delay calculated from stapes-velocity phase showed a decrease in transmission delay of about 150 µs by TT pulls and 60 µs by St pulls. Our interpretation of these results is that ME-muscle activity may provide a way of mechanically changing interaural time- and level-difference cues. These effects could help the brain align head-centered auditory and ocular-centered visual representations of the environment.
Topics: Animals; Humans; Tympanic Membrane; Ear, Middle; Stapes; Sound; Tensor Tympani; Temporal Bone; Vibration; Mammals
PubMed: 36821982
DOI: 10.1016/j.heares.2023.108721 -
Otology & Neurotology : Official... Feb 2022Demonstrate the ability of a novel steerable distal chip endoscope to traverse the Eustachian tube and provide diagnostic quality images of the human middle ear.
OBJECTIVE
Demonstrate the ability of a novel steerable distal chip endoscope to traverse the Eustachian tube and provide diagnostic quality images of the human middle ear.
PATIENTS
Three cadaveric temporal bone specimens were used in this work.
INTERVENTION
Diagnostic transeustachian endoscopy of the middle ear was performed.
MAIN OUTCOME MEASURE
Diagnostic image quality.
RESULTS
A novel 1.62 mm steerable endoscope successfully cannulated the Eustachian tube of three human cadaveric temporal bone specimens to reveal intact middle ear anatomy with high optical clarity.
CONCLUSIONS
A steerable endoscope can be designed to traverse the human Eustachian tube and provide diagnostic quality images of middle ear anatomy.
Topics: Cadaver; Ear, Middle; Endoscopes; Endoscopy; Eustachian Tube; Humans
PubMed: 34669684
DOI: 10.1097/MAO.0000000000003384 -
Journal of Anatomy Feb 2016Here we present a brief, historical review of research into the mammalian middle ear structures. Most of their essential homologies were established by embryologists,... (Review)
Review
Here we present a brief, historical review of research into the mammalian middle ear structures. Most of their essential homologies were established by embryologists, notably including Reichert, during the 19th century. The evolutionary dimension was confirmed by finds of fossil synapsids, mainly from the Karroo of South Africa. In 1913, Ernst Gaupp was the first to present a synthesis of the available embryological and paleontological data, but a number of morphological details remained to be solved, such as the origin of the tympanic membrane. Gaupp favoured an independent origin of the eardrum in anurans, sauropsids, and mammals; we support most of his ideas. The present review emphasizes the problem of how the mammalian middle ear structures that developed at the angle of the lower jaw were transferred to the basicranium; the ontogenesis of extant marsupials provides important information on this question.
Topics: Animals; Biological Evolution; Biomedical Research; Developmental Biology; Ear, Middle; History, 19th Century; History, 20th Century; History, 21st Century; Mammals; Phylogeny
PubMed: 26397963
DOI: 10.1111/joa.12379 -
Hearing Research Jan 2023The time delay and/or malfunctioning of the Eustachian tube may cause pressure differences across the tympanic membrane, resulting in quasi-static movements of the... (Review)
Review
The time delay and/or malfunctioning of the Eustachian tube may cause pressure differences across the tympanic membrane, resulting in quasi-static movements of the middle-ear ossicles. While quasi-static displacements of the human middle-ear ossicles have been measured one- or two-dimensionally in previous studies, this study presents an approach to trace three-dimensional movements of the human middle-ear ossicles under static pressure loads in the ear canal (EC). The three-dimensional quasi-static movements of the middle-ear ossicles were measured using a custom-made stereo camera system. Two cameras were assembled with a relative angle of 7° and then mounted onto a robot arm. Red fluorescent beads of a 106-125 µm diameter were placed on the middle-ear ossicles, and quasi-static position changes of the fluorescent beads under static pressure loads were traced by the stereo camera system. All the position changes of the ossicles were registered to the anatomical intrinsic frame based on the stapes footplate, which was obtained from µ-CT imaging. Under negative ear-canal pressures, a rotational movement around the anterior-posterior axis was dominant for the malleus-incus complex, with small relative movements between the two ossicles. The stapes showed translation toward the lateral direction and rotation around the long axis of the stapes footplate. Under positive EC pressures, relative motion between the malleus and the incus at the IMJ became larger, reducing movements of the incus and stapes considerably and thus performing a protection function for the inner-ear structures. Three-dimensional tracing of the middle-ear ossicular chain provides a better understanding of the protection function of the human middle ear under static pressured loads as immediate responses without time delay.
Topics: Humans; Ear, Middle; Ear Ossicles; Incus; Stapes; Rotation
PubMed: 36462376
DOI: 10.1016/j.heares.2022.108651