[Pathognomonic signs of congenital anomalies of external and middle ear. Radiological examinations (author's transl)].
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Ear↗
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Results for “Ear, External”
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[Use of the analgetic-tranquilizing preparations in surgical treatment of children with congenital defects of the external and middle ear].
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Adolescent↗
[Current possibilities in microsurgery of the external and middle ear, and the mastoid].
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Ear Diseases↗
Molecular biological diagnosis of congenital and acquired cholesteatoma on the basis of differences in telomere length.
OBJECTIVE: To establish a molecular biological basis for differentiation of congenital and acquired cholesteatoma. STUDY DESIGN: The time of onset was estimated for congenital cholesteatoma and for acquired cholesteatoma by comparing the telomere length and the telomerase activity in the tissues of both diseases with the values of those parameters in normal external ear canal skin. METHODS: The telomere length was determined by extracting DNA from each tissue and then applying the Southern blot technique to hybridize it with a 32P-labeled telomeric oligonucleotide (TAAGGG)8 probe. The telomerase activity was analyzed by a modification of the polymerase chain reaction-based telomeric repeat amplification protocol. RESULTS: The telomere length in congenital cholesteatoma tissue was shorter than the length in normal external ear canal skin from the same patient, whereas in acquired cholesteatoma tissue the telomere length was almost the same as in the normal external ear canal skin. Some of the acquired cholesteatoma tissue specimens and normal external ear canal skin specimens were positive for telomerase activity, but all of the specimens of congenital cholesteatoma tissue were negative for telomerase activity. No correlation was found between the presence of telomerase activity and the telomere length. CONCLUSIONS: The present results indicate that congenital cholesteatoma manifests at an earlier time compared with acquired cholesteatoma, and the results can be thought to support the theory that congenital cholesteatoma originates from vestigial fetal tissue or aberrant tissue. In addition, the finding that telomerase activity was weak in the congenital cholesteatoma tissue suggests the possibility that vestigial fetal tissues and aberrant tissues are naturally eliminated in normal subjects as a result of apoptosis.
Adolescent↗
Water bolus for electron irradiation of the ear canal.
PURPOSE: To demonstrate that water bolus in the external ear can decrease the dose inhomogeneity caused by auricular surface irregularities when the ear is in an electron-beam field. METHODS AND MATERIALS: Three-dimensional (3D) dose distributions with and without water bolus in the external ear were calculated for a representative patient. The electron dose calculations were made using the Hogstrom pencil beam algorithm as implemented in 3D by Starkschall. To demonstrate the use of water bolus in the ear clinically, the case of a patient with squamous carcinoma of the concha who was treated with electrons is presented. RESULTS: Water bolus markedly lessens the dose heterogeneity caused by the surface irregularities of the ear and the air in the external auditory canal. In the test case, the maximum dose was reduced by 25% using this technique. CONCLUSION: When the ear is in an electron beam field, warm water should be placed in the external auditory canal and concha. This maneuver may reduce the incidence of auricular complications that occur after electron-beam therapy.
Aged↗
Congenital postauricular swelling in a child.
First branchial cleft cysts develop as a result of incomplete fusion of the cleft between the first and second branchial arches. In 1972, Work introduced a modified classification of these anomalies that recognized the existence of two types. Type I lesions, which are extremely rare, present as a cystic mass posterior to the pinna and concha. Type II lesions represent a duplication of both the membranous and cartilaginous portions of the external ear canal. They are associated with fistulas in the concha or in the external ear canal. Clinical and surgical management is often difficult because these anomalies have a variable relationship to the facial nerves. We describe a rare localization of a type I first branchial cleft cyst in a child and the clinical management with successive surgical treatment.
Branchial Region↗
[Useful imaging of the ear].
Good anatomical knowledge is necessary to make an effective diagnosis in ear pathology. The purpose of this article is to summarize the main landmarks of the ear. Anatomic definitions of the external ear, middle ear, and bony labyrinth are described on routine spiral CT, and the anatomic definition of the membranous labyrinth and the cochleovestibular nerve on MRI is reviewed.
Auditory Pathways↗
Spatial processing within the mustache bat echolocation system: possible mechanisms for optimization.
1. The directionality of an echolocation system is determined by the acoustic properties of both the emitter and receiver, i.e., by the radiation pattern of the emitted pulse and the directionally of the external ears. We measured the directionality of the echolocation system of the greater mustache bat (Pteronotus parnellii) at the 30 kHz, 60 kHz and 90 kHz harmonics of its echolocation pulse by summing, at points throughout the frontal sound field, the echo attenuation due to the spread of pulse energy and the attenuation due to the spread of pulse energy and the attenuation due to the directionality of its external ears. The pulse radiation pattern at the 3 harmonics was measured by comparing the output of a microphone moved throughout the frontal sound field against a second reference microphone at the center of the field. External ear directionality at the 3. harmonics was measured by presenting free-field sounds throughout the frontal sound field, and recording the intensity thresholds of cochlear microphonic potentials, and the intensity thresholds of monaural neurons in the inferior colliculus tuned to one of the 3 harmonics. 2. When compared with ear directionality, the echolocation system was found to be more directional for the center of the sound field in several respects. At all harmonics, attenuation of sounds originating in the peripheral part of the field was increased by 10 to 13 dB. Areas of maximum sound intensity contracted toward the center of the field. Also, the isointensity contours of the echolocation system were more radially symmetrical about the center of the field. 3. At 60 kHz, sound intensity along the azimuth within the echolocation system was nearly constant 26 degrees to either side of the center of the field. This suggests that the radiation pattern of the echolocation pulse and the directionality of the external ears complement one another to produce an acoustic environment at the center of the sound field in which stimulus intensity is stabilized to allow more effective analysis of various aspects of the echolocation target. In particular, we suggest that this intensity stabilization may allow the bat to more effectively resolve the interaural intensity differences it uses to localize prey. 4. Predictions of the azimuthal spatial tuning of binaurally sensitive neurons in the inferior colliculus within the echolocation system were compared with their spatial tuning when only ear directionality is considered.(ABSTRACT TRUNCATED AT 400 WORDS)
Acoustic Stimulation↗
Directionality of sound pressure transformation at the pinna of echolocating bats.
The directionality of sound pressure transformation at the pinna of three species of bats was studied by measuring the sound pressure level of a tone (25 45 65 and 85 kHz) at the tympanic membrane as a function of azimuth and elevation of the sound source under free-field conditions. The tympanic sound pressure level varied with location of the sound source. The directionality of sound pressure transformation pattern of the pinna of each bat was studied by plotting isopressure contours. The area within each isopressure contour decreased with increasing tonal frequency. For each tonal frequency, the point of maximal sound pressure was always located in the frontal ipsilateral sound field. This point shifted medially with increasing tonal frequency along the horizontal plane in all species tested, but it shifted in a species-specific manner along the vertical plane. Removal or distortion of the pinna and tragus resulted in either uncircumscribed or irregular isopressure contours for all tonal frequencies tested. Acoustic pressure gain of the external ear reached 16-23 dB for frequencies at 15-18 kHz. The importance of the external ear to the directionality of the bat's echolocation system is discussed.
Acoustics↗
Otoplasty: evaluation, technique, and review.
Prominent ear deformity is the most common abnormality of the external ear. Over two hundred different techniques have been described to correct this deformity. Many of these techniques have proven successful in their ability to achieve high patient satisfaction despite the significant variations in these techniques. From this perspective otoplasty is a privileged procedure allowing the surgeon great latitude in his approach and ability to achieve patient satisfaction. Despite high patient satisfaction, each technique has inherent strengths and weaknesses. The art of otoplasty is in the ability to realize the strengths and weaknesses of a cadre of procedures so as to maximize benefit and minimize complication. Analysis and correction of prominent ears should be approached in a rational, step-wise fashion. The external ear is an infinitely complex structure with great variation between individuals and between the two sides of the same individual. Appropriate evaluation is essential to the application of the appropriate corrective technique. Our approach to otoplasty includes a careful evaluation and description of the deformity in the context of normative standards and the goal of symmetry. When the patient is judged to be sufficiently mature we proceed with an algorithmic application of cartilage-sparing techniques suited to the specific deformity. In this approach, correction of the prominent ear can go beyond patient satisfaction, maximizing outcome in form and symmetry.
Age Factors↗
[Expression of transforming growth factor-beta1 and c-fos and p27 in human middle ear cholesteatoma].
OBJECTIVES: To analyze the expression of transforming growth factor-beta1 (TGF-beta1), cyclin dependent kinase inhibitor (p27) and c-fos in human middle ear cholesteatomas and to investigate the correlation between their expression and the ability of erosion of cholesteatoma. METHODS: Immunohistochemical staining (SP method) of 31 cholesteatomas and 11 external ear canal skin samples from patients and 10 external ear canal skin samples from healthful men which were taken intraoperatively, was performed for c-fos, TGF-beta1 and p27 positivity. The signals representing the expression of c-fos, TGF-beta1 and p27 were observed under microscope and scanned into a computer by an image scanner. The gray-scale of positive signals were quantitated by image processing computer. RESULTS: The percentage of positive expression of TGF-beta1 and c-fos in cholesteatoma were 87.1% and 83.9%, respectively. Their expression tended to be increased greatly compared with which in the skins of the control groups. Positive p27 signals were not observed in cholesteatomas and external ear skin tissues. It showed statistically significant correlation between expression of c-fos and the ability of erosion of cholesteatoma. There was correlation between the express ion of TGF-beta1 and the ability of erosion of cholesteatoma too. But there was no correlation between the expression of c-fos and TGF-beta1. CONCLUSION: The expression of c-fos in cholesteatoma was significally higher compared with which in the skin of external auditory of cholesteatoma patients and healthful men, which indicate that c-fos plays an important role in the hyperproliferative of cholesteatoma. The expression of TGF-beta1 was significant higher in cholesteatoma, which indicate that cytokines such as TGF-beta1 play a great role in the etiology of cholesteatoma.
Adult↗
The draining ear. Otitis media and externa.
Otorrhea, or discharge from the ear, may be associated with otitis media or otitis externa. Each episode of otorrhea requires examination of the external ear canal and middle ear to determine the origin and extent of disease, a complete understanding of the pathogenesis, and a therapeutic approach that considers the microbiology and the extent of tissue invasion. This review focuses on infections of the middle ear and external ear commonly associated with otorrhea. The pathogenesis, clinical manifestations, methods of diagnosis, and medical and surgical therapies are presented.
Acute Disease↗
Postoperative ramifications of total ear replantation.
Complete avulsion of the external ear, much less common than other minor ear trauma, presents a complex and difficult problem. The authors present a 35-year-old male cigarette smoker who suffered traumatic avulsion of the right ear, and describe the replantation procedure and the patient's postoperative course. Aesthetic positioning of the replanted ear, treating the external auditory meatus, protecting the ear against exposure to the sun, and counseling the patient about issues related to sensation are important factors in the care of patients who have undergone such a procedure.
Adult↗
Surgical management of acute ear canal separation in a cat.
A 5-year-old cat presented with haemorrhagic left aural discharge, 2 days following a road traffic accident. Otoscopic examination identified disruption of the external ear canal at the auricular/annular cartilage junction. This was managed by total ear canal ablation and lateral bulla osteotomy. Left sided facial nerve deficits were present following surgery. Eighteen months postoperatively there were no auricular problems, however facial nerve deficits persisted. There are no previous reports describing management of acute separation at the auricular/annular cartilage junction of the external ear in the cat or dog. This case report describes the presentation, diagnosis and surgical management of an acute ear canal separation at the auricular/annular junction of the external ear canal in a cat.
Accidents, Traffic↗
[Oto-vertebral syndrome].
The oto-vertebral syndrome is supposed to be caused by an early embryonic exogenous damage which at the same time affects the development of the ear and vertebral column and possibly also causes cardiac anomalies. Animal studies showed that the malformation syndrome originates in the 6th-7th week of embryonic development. The extent of the malformations of the ear and the vertebral column varies. Frequently seen are dysplasia of the external ear and dystopia and atresia of the external ear canal as well as vertebral malformations, mostly involving the thoracic region. Only 4 case reports have been published in the literature. The differential diagnosis includes Goldenhar-syndrome, oculo-vertebral syndrome. Thalidomide-syndrome and chromosomal aberrations. Therapy depends on the extent of the malformations. In case of atresia of the ear canal hearing is first of all improved with a hearing aid, operative procedures are to be planned later on. Child development is promoted with acustic stimulation.
Abnormalities, Multiple↗
The middle ear of gekkonoid lizards: interspecific variation of structure in relation to body size and to auditory sensitivity.
Wishing to assess the effects of the dimensions of the middle ear on the auditory sensitivity of gekkonoid lizards, we measured middle ear components in preserved geckos, which in life had yielded 'cochlear microphonics' audiograms. We examined two to seven specimens of 14 species. The measures of middle ear elements varied relative to head or body length similarly within species and among species. The areas of the external ear opening, tympanic membrane, and columellar footplate, and the ratio between the last two ('hydraulic lever'), were correlated with animal length. The hydraulic and mechanical (extracolumellar) lever ratios appeared to complement each other, the former being emphasized in large animals, the latter in small animals. The apparent auditory sensitivity correlated with the sizes of the animal, head and external ear opening, and negatively (insignificantly) correlated with the mechanical lever ratio. The correlation of sensitivity with the hydraulic lever was insignificant, perhaps due to a 'tympanic membrane lever' (catenary effect). The most sensitive frequency negatively correlated with the area of the external ear opening, the area of the tympanic membrane, and with the level of greatest sensitivity. It was positively correlated with the relative length of the cartilaginous portion of the ossicular chain. However, the number of hair cells in the basilar papilla, too, is known to correlate with animal size. Moreover, the least sensitive species were not only the smallest species, they were also the species known to lack a zone of unidirectional hair cells in the basilar papilla. Hence the apparent sensitivity hypothetically depends on both middle ear dimensions and summation of inner ear output. This hypothesis requires verification by other methods.
Animals↗
External and middle ear trauma resulting from ear impressions.
When taking an impression of the external ear canal and ear, the audiologist is engaged in an invasive procedure whereby a foreign body is first placed into the ear canal and then removed. There is always an element of risk for significant medical problems when a clinician is performing an invasive procedure. Although some minor patient discomfort and, at times, some slight trauma to the ear canal occur when taking ear impressions, the incidence of significant trauma to the external or middle ear appears to be low. The purpose of this report is to provide some illustrative cases of significant external and middle ear trauma as a result of taking impressions of the external ear. Audiologists are advised to develop and implement an appropriate risk management program for taking ear impressions to reduce the potential risks associated with this procedure to their patients and to their practices.
Aged↗
[Ultrasound measurement of skin and cartilage thickness in healthy and reconstructed ears with a 20-MHz ultrasound device].
BACKGROUND: The surgical reconstruction of the external ear according to Weerda is a proven method to correct malformed or amputated auricles. Our goal was to test the usefulness of high-frequency ultrasound in measurement of layer-thickness of auricles. METHOD: Using a 20-MHz B-Mode ultrasonographic method (Dermascan C, adn-Medizintechnik, Hamm, Germany) we measured the thickness of skin and cartilage layers in patients with normal auricles (n = 47) and reconstructed auricles (n = 15) in vivo. RESULTS: The average thickness of the cutis of normal auricles was 0.8 mm, the subcutis and the cartilage layer 0.6 mm thick on average. In reconstructed auricles, the thickness of the cutis averaged 1.0 mm, the subcutis 1.1 mm, and the cartilage layer (to the extent that it could be visualized) 3.0 mm. DISCUSSION: The results demonstrate a good approximation of the thicknesses of the different layers (cutis and subcutaneous tissue) in reconstructed and natural external ears, but the cartilage of the reconstructed auricles is clearly thicker. CONCLUSIONS: The 20-MHz B-Mode ultrasound is suitable for examining the methods of plastic surgery in malformed auricles. Based on the demonstrated results, surgical modifications should be assessed in future.
Adolescent↗