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At least 19 recordsLinked to original sources

Pulse volume recordings in outer ear canal in pulse synchronous tinnitus. A comparison between ears with Glomus tumour, serous otitis media, and normal ears.

With the aid of a volume flowmeter it is possible to record pulse synchromous volumetric changes in the outer ear canal. In 7 ears with glomus tumour in the tympanic cavity and in 5 with serous otitis media, such changes were larger than in 125 persons with a normal middle ear. By changing the ambient pressure in a pressure chamber and instructing the patients not to swallow, the drum can be pushed inward or outward. In all the cases of glomus tumour studied the pulse volumetric change was considerably affected when the drum was pushed inward or outward. In the normal patients the change was no change at all. This means that the pulse volume changes in normals are generated mainly by the vessels in the outer ear canal.

Adolescent

Tissue reaction to middle ear prostheses: in vivo observation (rabbit ear lobe) of polyethylene tube, stainless steel wire and absorbable gelatin sponge used in middle ear surgery.

Over the past ten years, polyethylene tube, stainless steel wire and absorbable gelatin sponge have come to be used in middle ear surgery. A modified Williams' steel chamber with a transparent central area was embedded in a rabbit ear lobe surgically, and cross-sectioned polyethylene tube, stainless steel wire or absorbable gelatin sponge were inserted respectively. The in vivo tissue reaction to each of these installed materials was observed daily microscopically. Finally, in the case of both the cross-sectioned polyethylene tube and the stainless steel wire, the chambers were fixed with 10% formalin solution and the contents stained for histological study. The results were as follows: Absorbable gelatin sponge was absorbed completely by phagocytosis in 62 days. Polyethylene tube was encapsulated by a layer of fibroblasts by day 110 in one case and by day 140 in another case; these findings were confirmed histologically on day 110 and 281. Almost all the surface of the stainless steel wire was encapsulated by a layer consisting of giant cells, on which a dense fibrous layer was superimposed by day 82. It is concluded that polyethylene tube, stainless steel wire, and absorbable gelatin sponge should be well tolerated in middle ear surgery.

Absorption

Long-term observation of ears with reduced middle ear pressure.

335 ears from 210 childred in which tympanometry initially indicated middle ear pressure less than or equal to -100 mm H2O or a flat tympanogram have been reinvestigated 3 years later. When the inital investigation was performed all children were 7 years old. The present study reveals that 25% of these ears still have middle ear pressure less than or equal to -100 mm H2O and 16% middle ear pressure less than or equal to -150 mm H2O. In normal material of the same age group 9% have middle ear pressure less than or equal to -100 mm H2O and 4% middle ear pressure less than or equal to -150 mm H2O. The study also reveals effusion in 10% of ears with normal screening audiograms. In ears with normal screening audiograms and middle ear pressure greater than or equal to -145 mm H2O effusion was found in 5% and in ears with abnormal screening audiograms and middle ear pressure less than or equal to -150 mm H2O effusion was found in 81%. As tympanometric criterion for otologist referral, middle ear pressure less than or equal to -150 mm H2O or a flat tympanogram is suggested. The inclusion of tympanometry in routine screening for middle ear pathology in children is recommended.

Acoustic Impedance Tests

The burned ear (II): A prospective clinical study of 100 patients with 150 ear burns.

A prospective clinical study of 100 patients with 150 ear burns was carried out in the Burns Centre, Singapore General Hospital. The aims of this study were to document the nature of the injury, the results of various methods of treatment, the complications of ear burns and the changes that led to chondritis. Based on the findings of the experimental studies on the burned ear, it is possible to accurately classify the depth of the burn injury based on the surface appearance. The results show that fire was the commonest aetiologic agent for ear burns (65% cases) and hot water scalds second (25% cases). Scalds tended to cause unilateral ear burns whilst fire caused bilateral injuries. The single most important factor in healing of the burned ear was the depth of the injury. Erythema took six days, mid-dermal (MD) burns ten days, uncomplicated deep-dermal (DD) and full thickness (FT) burns 35 days. When chondritis developed deep dermal burns took 43.5 days to heal and full thickness burns took 57.8 days. Conservative treatment of 104 ears resulted in complete healing except for 15 which had pigmentary and/or hypertrophic scar problems. Surgical treatment was used in 23 ears. Three returned to normal appearance, eleven had mild and four had moderate deformities. Five ears were lost (3% cases). Chondritis was present in 12 ears (8% cases), six in DD and six in FT burns. Seven of these ears were successfully salvaged. Favourable results in this study were attributed to the following factors: early detection of chondritis by the EAR SPRINGING SIGN, early surgical intervention, radical cartilage removal, meticulous post-op care to prevent cross infection and avoidance of pressure to the ears.

Adolescent

Clearance of middle ear effusions and middle ear pressures.

Twenty-six children presenting bilateral secretory otitis media (SOM) had ventilating tubes inserted into both middle ears. Mucus was, however, aspirated only from one ear, the right side. The vast majority of ears right and left were seen to have cleared their effusion equally well regardless of whether they were aspirated on not. This experiment points toward the essential intactness of the mucociliary system and the patency of the lumen of the Eustachian tube in SOM. Promotion of middle ear clearance through ventilation, which reminds one of the second opening in a beer can, does obviously suggest the relief of some negative pressure. Direct manometric measurements of SOM middle pressure were performed in 41 ears showing negative pressure averaging --1.7 mm H2O, this range being two orders of magnitude less than tympanometric measurements. Normal ears did not have even such a small negative pressure. The validity of these direct manometric measurements was checked against a model of the middle ear. Tympanometry, which is a valid diagnostic tool, does indicate in all probability the presence of middle ear effusion due to its rheologic effects on the drum and ossicles rather than the measure of actual middle ear pressures. This is determined by the fact that direct needling of the middle ear, or even the insertion of a ventilating tube, did not change tympanometric values but aspiration of part of the effusion did: indeed the latter tended to bring manometry to normal values.

Child, Preschool

A single-blind, randomized study to compare the efficacy of two ear drop preparations ('Audax' and 'Cerumol') in the softening of ear wax.

A parallel group, single-blind, randomized study was carried out in a general practice to compare the effectiveness and tolerability of two ear drop preparations ('Audax' and 'Cerumol') in the softening of ear wax in 50 adult patients with impacted or hardened ear wax. Assessments were made on entry of the amount, colour and consistency of the ear wax, symptoms, and objective hearing. Patients were then allocated at random to receive one or other preparation and instructed to use the drops, morning and evening, for 4 days after which they were reassessed. Details were recorded of any side-effects or discomfort caused by the study medication and both physician and patients were asked to give their overall opinion of treatment efficacy. Both treatments were shown to be effective in the softening of ear wax and were well tolerated, there being no significant difference between the two groups in these parameters. However, patients who had abnormal hearing before treatment had a significantly greater improvement in objective hearing after treatment with 'Audax' ear drops compared to those patients treated with 'Cerumol' ear drops. There were no between-treatment differences in either either the physician's or patient's overall assessments of effectiveness.

Adolescent

Symposium: Congenital anomalies of the middle ear. III. Congenital anomalies of the middle ear.

Congenital anomalies of the middle ear have been considered rare. The tremendous volume of middle ear surgery performed during the last 15 years has brought attention to numerous anomalies of the facial nerve, ossicles, and middle ear cleft, suggesting that middle ear anomalies are not as rare as once believed. This paper discusses anomalies of the descending and horizontal facial nerve which have been previously reported. The literature of anomalies of the ossicles is reviewed. A very rare anomaly of the carotid artery presenting in the middle ear is described and its surgical treatment outlined. Two anomalies of the middle ear associated with other branchial arch anomalies are reported and their treatment results discussed.

Adolescent

Transcriptional regulation of human apolipoprotein genes ApoB, ApoCIII, and ApoAII by members of the steroid hormone receptor superfamily HNF-4, ARP-1, EAR-2, and EAR-3.

Apolipoproteins B, CIII, and AII are synthesized primarily in the liver and intestine and play an important role in lipid and cholesterol metabolism. It was previously shown that the cis-acting elements (BA1 (-79 to -63), CIIIB (-87 to -63), and AIIJ (-740 to -719) present in the regulatory regions of the human apoB, apoCIII, and apoAII genes, respectively, are recognized by common transcription factors present in hepatic nuclear extracts. This report shows that four members of the steroid receptor superfamily, ARP-1, EAR-2, EAR-3, and HNF-4, bind specifically to the regulatory elements BA1, CIIIB, and AIIJ. Dissociation constant measurements showed that ARP-1, EAR-2, and HNF-4 bind to elements BA1 and CIIIB with similar affinities (Kd 1-3 nM). Cotransfection experiments in HepG2 cells revealed that ARP-1, EAR-2, and EAR-3 repressed the BA1, CIIIB, and AIIJ element-dependent transcription of the reporter gene constructs and the transcription driven by homopolymeric promoters containing either five BA1 or two CIIIB elements. In contrast, HNF-4 activated transcription of reporter genes containing the elements BA1, CIIIB, and AIIJ and reversed the ARP-1-mediated repression of the apoB and apoCIII genes. These results suggested that the opposing transcription effects observed between HNF-4 and ARP-1 may be due to competition for binding to the same regulatory element. Mutations which affected the binding of HNF-4 to elements BA1 and CIIIB affected its ability to activate transcription of the apoB and apoCIII reporter genes, respectively. Transcriptional activation by HNF-4 depended on the presence of elements II (-112 to -94) and III (-86 to -62) of the apoB and H (-705 to -690), I (-766 to -726), and J (-792 to -779) of the apoCIII promoters, indicating that transcriptional activation of apoB and apoCIII genes by HNF-4 requires the synergistic interaction of factors binding to these elements. The finding that HNF-4, ARP-1, EAR-2 and EAR-3 can regulate the expression of the apoB, apoCIII, and apoAII genes suggest that these nuclear hormone receptors may be an important part of the signal transduction pathways modulating lipid metabolism and cholesterol homeostasis.

Animals

A comparison of the efficacy of two ear drop preparations ('Audax' and 'Earex') in the softening and removal of impacted ear wax.

Thirty-six patients with symptoms of impacted ear wax were recruited to an open, randomized, parallel group study of 'Audax' ear drops and 'Earex' ear drops. Patients had had their symptoms for several weeks and they were assessed on entry for the degree of impaction in each ear. After using the drops, morning and evening for 4 days, they were assessed on the fifth day for degree of impaction, ease of syringing, side-effects or discomfort, and the investigator's and patient's own global impression of efficacy of the ear drops. A trend was seen showing less impaction post-treatment in the 'Audax' group than in the 'Earex' group although the difference did not reach statistical significance. A significant difference was seen in favour of 'Audax' for the frequency and ease of syringing (p < 0.005). No patients in the 'Audax' group reported any side-effect or discomfort although 1 patient using 'Earex' reported slight irritation whilst another found the smell unacceptable. The results of the investigators' and patients' own global impression of efficacy were significantly in favour of 'Audax' ear drops (p < 0.01).

Adolescent

Collapsing ears and acoustic reflex measurement with circumaural ear cushions.

Ears that collapse from audiometer ear cushion pressure may show elevated stapedial reflex thresholds. In such cases, erroneous judgments about the status of a patient's hearing are possible. Experiments on 15 normal ears suggest that the use of a circumaural ear cushion on the impedance audiometer headset is an effective method of eliminating outer ear closure and the resulting spurious thresholds, when the proper correction values by frequency are applied to the audiometer dial reading. In this study, correction values for reflex-eliciting stimuli are established and their use in a child with collapsing ears is reported.

Acoustic Stimulation

Real ear unaided responses in ears with tympanic membrane perforations.

This study evaluated 13 adult patients with tympanic membrane (TM) perforations in one or both ears. Probe microphone real ear unaided responses (REURs) for mean peak frequency and peak dB gain showed no substantial differences among patients, across ears with intact TMs, ears with TM perforations (regardless of size), or between measures taken before and after closure of the perforations. Inspection of individual differences in the patients' REURs, however, produced an interesting finding. The REURs of ears having small TM perforations did not differ from those with intact TMs, but the REURs for ears having larger perforations consistently revealed bimodal responses (two prominent peaks separated by a valley of at least 10 dB lower gain). Thus, size of the perforation affected the REURs.

Acoustics

[Chronic mucous effusions of the middle ear and the influence on inner ear function (author's transl)].

Audiometric recordings of children suffering from chronic mucous effusion of the middle ear have revealed a statistically significant and permanent sensorineural hearing loss of high frequences. Attemps for mechanical or physical factors as explanation are not convincing. We believe that inner ear disturbances in chronic mucous effusion rise by direct intoxication of the basal turns of the cochlea caused by pathologic alterations of mucous membrane tissue. Certain substances like lysozymes or histamine are supposed to diffuse via round window membrane to the inner ear. On the other hand mucous effusion which fills the middle cavity prevents oxygen to diffuse from the middle ear to the inner ear. Maass et al. (1976) and Morgenstern (1977) clearly have shown that under physiological conditions oxygen tension in the perilymph of the basal cochlear turn partly depends on diffusion from the middle ear. The results of our clinical observations indicate that early diagnosis and prompt treatment is necessary to prevent permanent sensorineural hearing loss of high frequencies, especially in infants and children.

Audiometry

The evaluation of ear canal, middle ear, temporal bone, and cerebellopontine angle masses in infants, children, and adolescents.

Ear canal, middle ear, temporal bone, and CPA angle masses (except for cholesteatomas) are rare in the pediatric population. The physician needs to have a high degree of suspicion for such lesions if a child presents with ear pain unrelated to infection or otorrhea that fails to improve after treatment. A precise diagnosis needs to be made in these children and also in those with hearing loss, vertigo, and facial paralysis. The most useful imaging procedures for ear, temporal bone, and CPA masses are CT and MR imaging. With a suspected vascular lesion, a definitive diagnosis usually can be made by an imaging procedure or angiography. In all cases of mass lesions, except for some aneurysms and infections, a tissue diagnosis must be secured.

Adolescent

Rabbit's ear in cold acclimation studied on the change in ear temperature.

The role of the rabbit's ear in cold acclimation was studied by varying the temperature of a climatic room in the range from -10 to +30 degrees C; The skin temperature in a nonanesthetized rabbit's ear showed a characteristic response to changes in ambient temperatures; plotting the ear temperature against the ambient temperature yielded an S-shaped curve. The mean ambient temperature corresponding to the inflection point on the S-shaped curve shifted significantly from about 13 degrees C to about 8 degrees C after cold acclimated of a group fed for 7 wk at -10 degrees C. The shift of the S-shaped curve after cold acclimation may not be due to the change in the norepinephrine sensitivity of the vascular beds of the ear: the effect of norepinephrine on the pressure-flow curve in the isolated rabbit's ear was almost unchanged between the control and the cold-acclimated groups. It is proposed that the shift of the inflection point gives a qualitative index of the acclimated state of the rabbit at a particular temperature.

Acclimatization

Surgery of the 'only hearing ear' with chronic ear disease.

The management of chronic ear disease affecting the only hearing ear is a controversial subject. The relative scarcity of literature on the subject prompted us to prepare a questionnaire which was sent to European and American otologists and to review 19 cases operated at the ENT Clinic of the University of Parma, Italy, and 16 cases operated at The Baptist Memorial Hospital, Memphis, U.S.A. Surgery of cholesteatoma involving the only hearing ear is advised by all the interviewed otologists without exception, even in the presence of a labyrinthine fistula. The cases from the University of Parma were managed as follows: a classic modified radical mastoidectomy was performed in 10 cases, a staged intact canal wall tympanoplasty was done in four cases, an open tympanoplasty in three and a radical mastoidectomy in the remaining two cases. The cases from The Baptist Memorial Hospital were managed with an intact canal wall tympanoplasty (ICWT) in nine and with an open procedure in seven cases. All the otologists interviewed agreed that surgery of the only hearing ear requires particular attention and experience, and should be performed with extreme care by a very experienced surgeon.

Attitude of Health Personnel

Middle ear pressure following tympanoplasty for various middle ear diseases. Pressure related to follow-up period and retractions.

In 512 ears with various middle ear diseases, the middle ear pressure was measured a minimum of 2 years and a maximum of 10 years after tympanoplasty. The findings were related to the length of the follow-up period and to retractions of the drum and/or in the epitympanum. The tympanometric findings were best in sequelae to otitis with dry perforations, poorest in cholesteatomas and adhesive otitis. Tubal function had not further deteriorated 4 years after the operation. There was a highly significant correlation between the middle ear pressure and the frequency of retractions, which also does not essentially increase--except in the cholesteatoma cases.

Acoustic Impedance Tests

[The mechanics and function of the middle ear. Part 1: The ossicular chain and middle ear muscles].

The revelation of a sophisticated micro-mechanism within the ossicular chain--the gliding of the joints results in a characteristic change of the ossicular movement--extended our conception of the function of the ossicular chain. Contrary to our former ideas of the transmission of sound during hearing, the ossicles do not rotate around an axis, which runs through the center of mass of the malleus and anvil. The imaginary rotational axis is located outside the ossicles, resulting in a more piston-like vibration of the complete chain. The ossicular joints are rigid. This acoustic function of the ossicular chain must rigorously be separated from its behaviour at changes of static, ambient air pressure. The middle ear, working as a sensitive pressure receptor also reacts to these pressure changes with comparatively huge displacements of the drum membrane (visible in pneumatic otoscopy). Only now the malleus rotates around its axial ligaments. These movements cause a gliding motion in the malleus-incus joint, which results in a predominant up- and downward movement of the anvil; the incudo-stapedial joint glides, too, and the stapes (and the inner ear) are decoupled. This micro-mechanism explains several anatomical features of the middle ear construction, as there are the vertical alignment of the incudo-stapedial joint, the suspension of the anvil, the design of the malleus joint, etc. It also accounts for the peculiar anatomical arrangement of the middle ear muscles. Their function can be interpreted as preserving the intact cartilage of the ossicular joints.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals