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Journal of Comparative Physiology. A,... Sep 2020The sheep middle ear has been used in training to prepare physicians to perform surgeries and to test new ways of surgical access. This study aimed to (1) collect... (Comparative Study)
Comparative Study
The sheep middle ear has been used in training to prepare physicians to perform surgeries and to test new ways of surgical access. This study aimed to (1) collect anatomical data and inertial properties of the sheep middle-ear ossicles and (2) explore effects of these features on sound transmission, in comparison to those of the human. Characteristic dimensions and inertial properties of the middle-ear ossicles of White-Alpine sheep (n = 11) were measured from high-resolution micro-CT data, and were assessed in comparison with the corresponding values of the human middle ear. The sheep middle-ear ossicles differed from those of human in several ways: anteroinferior orientation of the malleus handle, relatively small size of the incus with a relatively short distance to the lenticular process, a large area of the articular surfaces at the incudostapedial joint, and a relatively small moment of inertia along the anterior-posterior axis. Analysis in this study suggests that structure and orientation of the middle-ear ossicles in the sheep are conducive to an increase in the hinge-like ossicular-lever-action around the anterior-posterior axis. Considering the substantial anatomical differences, outcomes of middle-ear surgeries would presumably be difficult to assess from experiments using the sheep middle ear.
Topics: Animals; Ear Ossicles; Ear, Middle; Hearing; Humans; Incus; Malleus; Sheep
PubMed: 32564138
DOI: 10.1007/s00359-020-01430-w -
European Archives of... Apr 2020Congenital cholesteatoma (CC) presents as a white pearl-like lesion behind a normal tympanic membrane (TM), without a history of otorrhea, infection, perforation or... (Meta-Analysis)
Meta-Analysis
PURPOSE
Congenital cholesteatoma (CC) presents as a white pearl-like lesion behind a normal tympanic membrane (TM), without a history of otorrhea, infection, perforation or previous otologic surgery. Several recent studies provided new data improving this pathology characterization. The aim of this paper is to expand the knowledge about CC and to provide new insights on its pathogenesis.
METHODS
The study consisted of two main research parts: (1) systematic review and meta-analysis; (2) medical literature review englobing anatomy, histology, embryology and congenital pathology of the ear.
RESULTS
The search strategy identified a total of 636 papers. Seventy retrospective studies were included. A total of 1497 cases were studied and the mean age was 6.58 years, with a male-female ratio of 3:1, 34% were asymptomatic, 26% had hearing loss and 2% had facial dysfunction/paralysis. The overall estimate for antero-superior quadrant involvement was 0.70 [95% confident interval (CI) 0.64-0.76], in the postero-superior quadrant was 0.60 (95% CI 0.52-0.69), in the antero-inferior quadrant was 0.32 (95% CI 0.23-0.41), in the postero-inferior quadrant was 0.38 (95% CI 0.29-0.47), in the attic was 0.53 (95% CI 0.43-0.63) and in the mastoid was 0.33 (95% CI 0.26-0.41). More advanced Potsic stages were present in older patients. The most likely inclusion place seems to be between the pars flaccida and the upper quadrants of the pars tensa.
CONCLUSIONS
During the last decades, a substantial improvement in CC diagnosis and management had been achieved. The presented mechanism seems to explain most of middle ear CC.
Topics: Cholesteatoma, Middle Ear; Ear, Middle; Humans; Mastoid; Tympanic Membrane
PubMed: 31955213
DOI: 10.1007/s00405-020-05792-4 -
European Archives of... Apr 2018To describe the in vivo vascularization of middle ear by an endoscopic point of view, particularly focusing on the medial wall of tympanic cavity and incudostapedial...
PURPOSE
To describe the in vivo vascularization of middle ear by an endoscopic point of view, particularly focusing on the medial wall of tympanic cavity and incudostapedial region (ISR).
STUDY DESIGN
Case series with surgical videos review and anatomical description.
METHODS
48 videos from exclusive endoscopic middle ear surgery performed at the University Hospital of Modena from November 2015 to July 2017 were reviewed. Data about anatomy of vessels, and blood flow direction (BFD) were collected in an appropriate database for further analyses.
RESULTS
48 cases were included in the present study. In 18/48 patients (37,5%), a clearly identifiable inferior tympanic artery (ITA) was present, running just anteriorly to the round window (RW), with a superior BFD (65% of cases) from the hypotympanic region toward the epitympanum. Some promontorial variants were described in 67% of cases and the most common finding was a mucosal vascular network with a multidirectional BFD. On the ISR, an incudostapedial artery (ISA) was detected in 65% of cases with BFD going from the long process of the incus (LPI) toward the pyramidal eminence in the majority of cases.
CONCLUSION
The vascular anatomy and BFD of the medial wall of the tympanic cavity can be easily studied in transcanal endoscopy. ITA (with a superior BFD in most cases) and ISA (with a main BFD from the incus to the stapes) are the most constant identifiable vessels.
Topics: Ear, Middle; Endoscopy; Humans; Microcirculation
PubMed: 29429024
DOI: 10.1007/s00405-018-4905-8 -
Otolaryngology--head and Neck Surgery :... Feb 2011
Topics: Adolescent; Carotid Artery, Internal; Diagnosis, Differential; Ear, Middle; Humans; Male; Otoscopy; Tomography, X-Ray Computed
PubMed: 21493434
DOI: 10.1177/0194599810391589 -
Brazilian Journal of Otorhinolaryngology 2023To describe the external and middle ear of goats, using computed tomography and endoscopic dissection, comparing them with the anatomy of the human ear, aiming to...
OBJECTIVE
To describe the external and middle ear of goats, using computed tomography and endoscopic dissection, comparing them with the anatomy of the human ear, aiming to evaluate the viability of this animal model for training in otological endoscopic surgery.
METHODS
Images of the external and middle ear of goats were produced by computed tomography in the coronal and axial planes and analyzed. The radiological anatomy of the external and middle goat and human ear are described. Some measures of surgical interest were described, such as the length of the external auditory canal, external and internal cross-sectional area of the external auditory canal, middle ear depth, vertical angle of the external auditory canal, length of malleus and incus. After the tomographic study, we analyzed the importance of evaluations through the endoscopic dissection of the goat ear.
RESULTS
The bony canal is extremely tortuous and shows a bony prominence with significant elevation near the lower edge of the tympanic membrane. The middle ear has a large tympanic bulla in the hypotympanum region. The malleus is shaped similarly to that of the human, but its handle is located anterior to its head. The mastoid is not pneumatized. Compared to the human mastoid, there was a statistically significant difference in the external and internal cross-sectional area, at the depth of the middle ear, in the vertical angle of the canal and in the length of the incus.
CONCLUSION
Goat morphometric anatomy showed that this model is suitable for surgical simulation in the initial training for endoscopic otological surgery. It is an important contribution to the development of skills to accelerate the subsequent endoscopic otological surgical training in humans, despite some differences found.
Topics: Animals; Humans; Goats; Ear, Middle; Tympanic Membrane; Malleus; Tomography, X-Ray Computed; Ear Canal
PubMed: 34740556
DOI: 10.1016/j.bjorl.2021.07.006 -
Otolaryngologic Clinics of North America Feb 1995In the selection of biomaterials for middle ear applications of implantable devices, certainly the site of implantation and the mass of the implant will dictate the... (Review)
Review
In the selection of biomaterials for middle ear applications of implantable devices, certainly the site of implantation and the mass of the implant will dictate the choice of biomaterials. Hermetic sealing of an implant is best achieved by the use of metals, not polymers. Osteocompatibility of an ossicular implant can be enhanced by the incorporation of calcium phosphates such as hydroxyapatite coatings. Finally, osseointegration or osseofixation is neither necessary nor desirable for ossicular implants, because (1) they may need to be removed or replaced in the future and (2) their solid fixation to an ossicle is not necessary for the vibratory function of hearing amplification.
Topics: Biocompatible Materials; Ear, Inner; Ear, Middle; Humans; Otolaryngology; Prostheses and Implants
PubMed: 7739863
DOI: No ID Found -
Hearing Research Jul 2013The middle ear apparatus varies considerably among living mammals. Body size, phylogeny and acoustic environment all play roles in shaping ear structure and function,... (Review)
Review
The middle ear apparatus varies considerably among living mammals. Body size, phylogeny and acoustic environment all play roles in shaping ear structure and function, but experimental studies aimed ultimately at improving our understanding of human hearing can sometimes overlook these important species differences. This review focuses on three groups of mammals, bringing together anatomical, zoological and physiological information in order to highlight unusual features of their middle ears and attempt to interpret their function. "Microtype" ears, found in species such as mice and bats, are associated with high-frequency hearing. The orbicular apophysis, the focus of some recent developmental studies on mouse ears, is characteristic of microtype mallei but is not found in humans or other "freely mobile" species. The apophysis increases ossicular inertia about the anatomical axis of rotation: its adaptive purpose in a high-frequency ear is still not clear. Subterranean mammals have convergently evolved a "freely mobile" ossicular morphology which appears to favour lower-frequency sound transmission. More unusual features found in some of these animals include acoustically coupled middle ear cavities, the loss of middle ear muscles and hypertrophied ossicles which are believed to subserve a form of inertial bone conduction. Middle ears of the rodent group Ctenohystrica (which includes guinea pigs and chinchillas, important models in hearing research) show some striking characteristics which together comprise a unique type of auditory apparatus requiring a classification of its own, referred to here as the "Ctenohystrica type". These characteristics include a distinctive malleus morphology, fusion of the malleus and incus, reduction or loss of the stapedius muscle, a synovial stapedio-vestibular articulation and, in chinchillas, enormously expanded middle ear cavities. These characteristics may be functionally linked and associated with the excellent low-frequency hearing found in these animals. The application of new experimental and imaging data into increasingly sophisticated models continues to improve our understanding of middle ear function. However, a more rigorous comparative approach and a better appreciation of the complex patterns of convergent and divergent evolution reflected in the middle ear structures of living mammals are also needed, in order to put findings from different species into the appropriate context. This article is part of a special issue entitled "MEMRO 2012".
Topics: Animals; Ear Ossicles; Ear, Middle; Guinea Pigs; Hearing; Mammals; Mice; Models, Anatomic; Moles; Phylogeny; Rodentia; Species Specificity
PubMed: 23099208
DOI: 10.1016/j.heares.2012.10.004 -
Acta Oto-rhino-laryngologica Belgica 1988After a profound review of normal embryology, a systematical and topographical classification of congenital middle ear malformations in general and of meatal atresia in... (Review)
Review
After a profound review of normal embryology, a systematical and topographical classification of congenital middle ear malformations in general and of meatal atresia in particular is proposed; the classification of congenital aural atresia is essentially based on the recognition of two types according to the course of the facial nerve in its third segment: in type I, a normal topography of the facial nerve is found and consequently, the middle ear anomalies are rather minimal; in type II, an antero-superior displacement of the facial nerve in its third segment is recognized and the middle ear malformations are considerable worse. In this report, also attention is paid to syndromal nosology and its genetic aspects. In view of functional surgical; reconstruction, the technique of allograft canal surgery, similar to our combined approach tympanoplasty technique, is described in detail and compared with other classical techniques. Preoperative as well as postoperative problems and complications are extensively discussed. The excellent results of our technique are proposed even after 25 years of experience. An overview of cosmetic surgery techniques is given and also alternative techniques with implantable auditory prosthetic materials are summarized.
Topics: Deafness; Ear Diseases; Ear, External; Ear, Middle; Hearing Disorders; Humans; Pedigree
PubMed: 3046227
DOI: No ID Found -
Journal of Visualized Experiments : JoVE Jan 2018The middle ear is located in the center of the temporal bone and bears a highly complex anatomy. The recently introduced exclusively endoscopic transcanal approach to...
The middle ear is located in the center of the temporal bone and bears a highly complex anatomy. The recently introduced exclusively endoscopic transcanal approach to the middle ear is a minimally invasive technique sparing the bone and mucosa of the mastoid bone, since the middle ear is accessed through the external auditory canal. This emerging method has several advantages over the traditional (microscopic) approaches to the middle ear such as the panoramic wide-angle views of the anatomy, the possibility to approach and magnify tiny structures, and the possibility of looking around the corner using angled endoscopes. The cadaveric dissection method presented here consists of an overview on the technical requirements and a precise description of a step-by-step protocol to discover the anatomy of the middle ear. Each step and anatomical structure is carefully described in order to provide a comprehensive guide to endoscopic ear anatomy. In our opinion, this is particularly important to any novice in endoscopic ear surgery as it provides thorough anatomical knowledge and may improve surgical skills.
Topics: Ear, Middle; Endoscopy; Humans; Manuals as Topic; Otologic Surgical Procedures
PubMed: 29364219
DOI: 10.3791/56390 -
The Journal of Allergy and Clinical... May 1988The middle ear is part of a functional system composed of the nasopharynx and the eustachian tube (anteriorly) and the mastoid air cells (posteriorly). The only active... (Review)
Review
The middle ear is part of a functional system composed of the nasopharynx and the eustachian tube (anteriorly) and the mastoid air cells (posteriorly). The only active muscle that opens the eustachian tube is the tensor veli palatini, which promotes ventilation of the middle ear. The eustachian tube also functions to protect the middle ear from excessive sound pressure, and nasopharyngeal secretions. The eustachian tube helps drain the middle ear during opening and closing by pumping secretions from the middle ear; clearance of secretions also occurs. An understanding of the anatomy and physiology of the system can aid the clinician in understanding the role of eustachian tube dysfunction in the cause and pathogenesis of middle ear disease and the possible contribution of allergy to this disease.
Topics: Adult; Age Factors; Child; Ear, Middle; Eustachian Tube; Humans; Nasopharynx; Otitis Media; Pressure
PubMed: 3286738
DOI: 10.1016/0091-6749(88)90168-6