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At least 55 records · Page 3Linked to original sources
PubMed1999

The effect of nasal continuous positive airway pressure on normal ears and on ears with atelectasis.

OBJECTIVES: The effect of short-term nasal continuous positive airway pressure (CPAP) on normal and atelectatic ears was studied to investigate the effect of positive pressure on these ears. STUDY DESIGN AND SETTING: This is a prospective study performed at the ear, nose, and throat clinic of a district general hospital. No randomization was designed for this study. PATIENTS: The study on the normal ears was performed on healthy volunteers, whereas the study on atelectatic ears was performed on patients who had difficulty in performing the Valsalva maneuver. INTERVENTION: Tympanometry, audiometry, and electronystagmography were performed on normal subjects before, during, and immediately after a single use of nasal CPAP. In the group of atelectatic ears, otoscopy and audiometry were performed before and immediately after the use of nasal CPAP (3 hours). MAIN OUTCOME MEASURE: The change in the middle ear pressure and hearing on the normal ears during the use of nasal CPAP was measured. In the group with atelectatic ears, the incidence of reinflation of the collapsed eardrum after the use of nasal CPAP was measured. RESULTS: Positive pressure was recorded in all the middle ears during the use of nasal CPAP, resulting in a reversible hearing impairment. More than two thirds of the atelectatic eardrums could be reinflated by a single use of nasal CPAP. CONCLUSION: Nasal CPAP could be used to deliver positive pressure into the middle ear and, hence, could be used as a device to reinflate a collapsed eardrum in many atelectatic ears.

Acoustic Impedance Tests↗
PubMed1991

Click- and tone-burst-evoked otoacoustic emissions in normally hearing ears and in ears with high-frequency sensorineural hearing loss.

Otoacoustic emissions (OAEs) evoked by clicks and tone bursts (TBs) were measured using a minor modification of the 1987 Bray and Kemp system in normal and hearing-impaired ears with high-frequency sensorineural hearing loss. Sixty ears of 60 subjects were tested. The average behavioral hearing threshold of 20 normally hearing ears was measured for the different "nonlinear" stimulus groups and defined as 0 dBnHL. Emissions were recorded in another 20 normally hearing ears and in 20 ears with steep high-frequency sensorineural hearing loss above 2kHz. An unfiltered click of 80 microseconds duration and TBs at frequencies of 0.5, 1, 2, 3, 4, 5, and 6 kHz served as stimuli. The ears with high-frequency hearing loss were clearly distinguished from the normal ears in that emission energy decreased with higher frequency stimuli above 2 kHz. The mean slopes of the response-growth functions were significantly higher at lower audiometric thresholds. The normal ears showed a slope of 0.21-0.35 dB/dBnHL above 2 kHz while the slope of the pathological ears was 0.04-0.13 dB/dBnHL. These differences in TBOAEs could possibly be used clinically to carry out hearing tests that are more frequency-specific than those measuring solely click-evoked OAEs. Pathological ears had emissions in the lower frequency range, where they had a normal audiometric threshold. However, these emissions had significantly far lower amplitudes at frequencies around 0.5 and 1 kHz when compared to normal ears. This reduced emission energy may indicate a cochlear impairment of the pathological ears in frequency ranges where they still had normal audiometric thresholds.

Acoustic Stimulation↗
PubMed2003

Ear-canal acoustic admittance and reflectance measurements in human neonates. II. Predictions of middle-ear in dysfunction and sensorineural hearing loss.

This report describes relationships between middle-ear measurements of acoustic admittance and energy reflectance (YR) and measurements of hearing status using visual reinforcement audiometry in a neonatal hearing-screening population. Analyses were performed on 2638 ears in which combined measurements were obtained [Norton et al., Ear Hear. 21, 348-356 (2000)]. The measurements included distortion-product otoacoustic emissions (DPOAE), transient evoked otoacoustic emissions (TEOAE), and auditory brainstem responses (ABR). Models to predict hearing status using DPOAEs, TEOAEs, or ABRs were each improved by the addition of the YR factors as interactions, in which factors were calculated using factor loadings from Keefe et al. [J. Acoust. Soc. Am. 113, 389-406 (2003)]. This result suggests that information on middle-ear status improves the ability to predict hearing status. The YR factors were used to construct a middle-ear dysfunction test on 1027 normal-hearing ears in which DPOAE and TEOAE responses were either both present or both absent, the latter condition being viewed as indicative of middle-ear dysfunction. The middle-ear dysfunction test classified these ears with a nonparametric area (A) under the relative operating characteristic curve of A = 0.86, and classified normal-hearing ears that failed two-stage hearing-screening tests with areas A = 0.84 for DPOAE/ABR, and A = 0.81 for TEOAE/ABR tests. The middle-ear dysfunction test adequately generalized to a new sample population (A = 0.82).

Diagnosis, Differential↗
PubMed1997

Analysis of middle ear mechanics and application to diseased and reconstructed ears.

OBJECTIVE: To review current concepts of the mechanical processes of the human middle ear, and to apply them to practical issues in clinical otology and tympanoplasty surgery. BACKGROUND: The wide range of conductive hearing losses associated with middle ear pathology and reconstruction cannot be adequately explained by simple models of middle ear function. METHODS: Variables used to describe the system are sound pressure, volume velocity, and acoustic impedance. The relationship between specific middle ear structures and these variables is described such that inferences can be drawn regarding sound conduction in the normal, diseased, and reconstructed middle ear. RESULTS AND CONCLUSIONS: Sound can be transmitted from the car canal to the cochlea via two mechanisms: the tympano-ossicular system (ossicular coupling) and direct acoustic stimulation of the oval and round windows (acoustic coupling). Acoustic coupling is negligibly small in normal ears, but can play a significant role in some diseased and reconstructed ears. In the normal ear, middle ear pressure gain (which is the result of ossicular coupling) is frequency-dependent and less than generally believed. The severity of conductive hearing loss due to middle-ear disease or after tympanoplasty surgery can be predicted by the degree to which ossicular coupling, acoustic coupling, and stapescochlear input impedance are altered. Hearing after type IV and V tympanoplasty is determined solely by acoustic coupling. The difference in magnitude between the oval- and round-window pressures is more important than the difference in phase in determining cochlear input. In tympanoplasty types I, II, and III, adequate middle-ear and round-window aeration is necessary and the tympanic membrane-ossicular configuration may be less crucial.

Acoustics↗
PubMed1988

Sensory innervation of the ear drum and middle-ear mucosa: retrograde tracing and immunocytochemistry.

The distribution and origin of nerve fibers of presumed sensory nature in the ear drum and middle-ear mucosa of the rat were studied by a retrograde tracing technique in combination with immunocytochemistry. Application of True Blue (TB) on the ear drum or on the middle-ear mucosa labeled nerve cell bodies in the jugular, trigeminal, geniculate and cervical dorsal root ganglia (C2-C4). Judging from the number of TB-labeled nerve cell bodies the jugular and trigeminal ganglia contributed the major component to the sensory innervation of the ear drum and the middle-ear mucosa, while the contribution from the geniculate and cervical dorsal root ganglia was relatively minor. The majority of the TB-labeled nerve cell bodies contained calcitonin gene-related peptide (CGRP), whereas minor populations stored substance P (SP) and neurokinin A (NKA). Nerve fibers containing SP, NKA and CGRP were moderate in number in the middle-ear mucosa and few in the ear drum. Double immunostaining revealed that SP invariably coexisted with NKA in nerve cell bodies in the ganglia examined. The SP/NKA-containing nerve cell bodies constituted a subpopulation of those storing CGRP. The findings indicate that several ganglia project to the ear drum and middle-ear mucosa and that many neuropeptides are involved in the mediation of middle-ear sensitivity.

Afferent Pathways↗
PubMed2001

Use of the 'real-ear to dial difference' to derive real-ear SPL from hearing level obtained with insert earphones.

The electroacoustic characteristics of a hearing instrument are normally selected for individuals using data obtained during audiological assessment. The precise inter-relationship between the electroacoustic and audiometric variables is most readily appreciated when they have been measured at the same reference point, such as the tympanic membrane. However, it is not always possible to obtain the real-ear sound pressure level (SPL) directly if this is below the noise floor of the probe-tube microphone system or if the subject is unco-operative. The real-ear SPL may be derived by adding the subject's real-ear to dial difference (REDD) acoustic transform to the audiometer dial setting. The aim of the present study was to confirm the validity of the Audioscan RM500 to measure the REDD with the ER-3A insert earphone. A probe-tube microphone was used to measure the real-ear SPL and REDD from the right ears of 16 adult subjects ranging in age from 22 to 41 years (mean age 27 years). Measurements were made from 0.25 kHz to 6 kHz at a dial setting of 70 dB with an ER-3A insert earphone and two earmould configurations: the EAR-LINK foam ear-tip and the subjects' customized skeleton earmoulds. Mean REDD varied as a function of frequency but was typically approximately 12 dB with a standard deviation (SD) of +/- 1.7 dB and +/- 2.7 dB for the foam ear-tip and customized earmould, respectively. The mean test-retest difference of the REDD varied with frequency but was typically 0.5 dB (SD 1 dB). Over the frequency range 0.5-4 kHz, the derived values were found to be within 5 dB of the measured values in 95% of subjects when using the EAR-LINK foam ear-tip and within 4 dB when using the skeleton earmould. The individually measured REDD transform can be used in clinical practice to derive a valid estimate of real-ear SPL when it has not been possible to measure this directly.

Acoustic Stimulation↗
PubMed1993

Profile of capsaicin-induced mouse ear oedema as neurogenic inflammatory model: comparison with arachidonic acid-induced ear oedema.

1. We have investigated the mechanism of capsaicin-induced mouse ear oedema compared with that of arachidonic acid (AA)-induced ear oedema, and evaluated the possible involvement of neuropeptides in the development of capsaicin-induced oedema. 2. Topical application of capsaicin (0.1-1.0 mg per ear) to the ear of mice produced immediate vasodilatation and erythema followed by the development of oedema which was maximal at 30 min after the treatment. This oedema was of shorter duration with less swelling than AA-induced oedema (2.0 mg per ear). 3. Capsaicin-induced ear oedema was unaffected when inhibitors of arachidonate metabolites including platelet activating factor (PAF) were administered before capsaicin (250 micrograms per ear) application, while these agents significantly prevented AA-induced oedema. Dexamethasone, histamine H1 and/or 5-hydroxytryptamine (5-HT) antagonists, and substance P (SP) antagonists were effective in inhibiting both models. Furthermore, a Ca(2+)-channel blocker and the capsaicin inhibitor, ruthenium red, were effective inhibitors of capsaicin oedema but had no effect on AA-induced oedema. 4. Phosphoramidon (50 micrograms kg-1, i.v.), an endopeptidase inhibitor, markedly (P < 0.001) enhanced only capsaicin-induced ear oedema, but bestatin (0.5 mg kg-1, i.v.), an aminopeptidase, failed to enhance oedema formation. 5. Neuropeptides (1-100 pmol per site) such as rat calcitonin gene-related peptide (CGRP), SP, neurokinin A (NKA), and vasoactive intestinal peptide (VIP), which are released from capsaicin-sensitive neurones, caused ear oedema by intradermal injection. Furthermore, a synergistic effect of CGRP (10 fmol per site) and SP (10 pmol per site) on oedema formation was observed. 6. The oedema induced by neuropeptides was significantly (P<0.05 or P<0.001) inhibited when cyproheptadine (20 mg kg-1, p.o.), a histamine H, and 5-HT antagonist, was administered before injection. In contrast, nifedipine (50 mg kg-1, p.o.), a Ca2+-channel blocker, and indomethacin(10 mg kg-1, p.o., except for NKA), a cyclo-oxygenase inhibitor, had little effect on neuropeptide induced oedema.7. These results suggest that the mechanism of capsaicin-induced ear oedema is different from that of AA-induced oedema and suggest that the development of capsaicin-induced ear oedema is primarily mediated by neuropeptides. The neuropeptides released after activation of sensory nerves cause an increase of vascular permeability by interactions with endothelial cells and by histamine (and 5-HT)release from mast cells.

Administration, Cutaneous↗
PubMed1988

Serous otitis media (S.O.M.). A bacteriological study of the ear canal and the middle ear.

A bacteriological study of the middle-ear effusions and the ear canals in children with chronic serous otitis media (S.O.M.) was performed. Sixty-eight children (127 ears) were investigated. From this study it appeared that cleansing of the ear canal with 0.5% chlorhexidine in 70% ethanol for 30 s is partially effective; micro-organisms (diptheroids, Staphylococcus epidermidis) could still be isolated in 29%. Cleansing of the ear canal decreases the incidence of middle-ear fluid contamination by non-pathogenic ear canal organisms (diptheroids, Staphylococcus epidermidis, Aerococcus), but after cleansing, 'non-pathogenic' micro-organisms could still be isolated in 33% of the effusions (diptheroids, Staphylococcus epidermidis). From 12% of the middle-ear effusions pathogenic micro-organisms (Hemophilus influenzae, Staphylococcus pneumoniae) were isolated; cleansing of the ear canal did not influence this percentage. Anaerobics were not isolated from the middle-ear effusions.

Adolescent↗
PubMed2001

[Feasibility of inner ear gene transfer after middle ear administration of an adenovirus vector].

BACKGROUND: Several groups demonstrated in animal experiments that gene transfer is a feasible tool for inner ear intervention. Various approaches for inoculation of vectors have been successfully used for inner ear gene therapy. One possible way to reduce the risk of hearing loss following the opening of the cochlea for application of the vector into the perilymphatic space is to deliver vectors through the round window. This study was designed to determine whether middle ear application of an adenoviral vector is a feasible approach to inoculate vectors and lead to transduction of cells in the inner ear. METHODS: A unilateral middle ear application of an adenoviral vector was performed in 4 guinea pigs directly on the round window membrane (RWM) and in 4 additional animals by placing a cotton patch soaked with the vector solution on the RWM. The expression of a reporter gene (lacZ) was used to localize vector-transduced cells. RESULTS: Only one out of 8 animals showed cochlear expression of the reporter gene, whereas all 8 animals showed strong lacZ expression in the middle ear mucosa, in the RWM and in the mucosa surrounding the stapes. CONCLUSION: Our results indicate that the RWM presents a close barrier, almost completely preventing the adenovirus to diffuse into the perilymphatic space. Therefore middle ear application of an adenoviral vector cannot be used to induce inner ear gene transfer. However, middle ear application of a viral vector may be useful for developing treatment for diseases of the middle ear mucosa.

Adenoviruses, Human↗
PubMed1996

Guinea pig inner ear antigens: extraction and application to the study of human autoimmune inner ear disease.

In this study, the authors attempted to develop a method of extracting guinea pig inner ear antigens for otoimmunological research, and to investigate the distribution of the antigens in the various structures of the inner ear. The antigens were extracted either from the entire or from various parts of the guinea pig inner ear. These antigens were separated on sodium dodecylsulfate-polyacrylamide gel electrophoresis (SDS-PAGE) gels. Western blot techniques were used to test sera from patients with inner ear disease against guinea pig inner ear protein extracts. It found that the various molecular weight antigens in the inner ear were associated with the different structures of the inner ear. The sera of 37.5% (N = 80) of patients reacted with two bands (30 and 58 kd) of the guinea pig inner ear immunoblots. The 58 kd band was not specific to the inner ear, but instead was also found in the immunoblots of other guinea pig tissues (brain, lung, and liver). This study suggests that the various antigens of interest could be further extracted and purified from the corresponding locations of the inner ear.

Animals↗
PubMed2003

Deriving the real-ear SPL of audiometric data using the "coupler to dial difference" and the "real ear to coupler difference".

OBJECTIVE: The purpose of the study was to compare the measured real-ear sound pressure level (SPL) of audiometer output with the derived real-ear SPL obtained by adding the coupler to dial difference (CDD) and real-ear to coupler difference (RECD) to the audiometer dial reading. DESIGN: The real-ear SPL and RECD were measured in one ear of 16 normally hearing subjects using a probe-tube microphone. The CDD transform and the RECD transfer function were measured in an HA1 and an HA2 2-cc coupler using an EAR-LINK foam ear-tip or a customized earmold. The RECD transfer function was measured using the EARTone ER 3A and the Audioscan RE770 insert earphone. RESULTS: The procedures were very reliable with mean differences on retest of less than 1 dB. The mean difference between the measured and derived real-ear SPL was generally less than 1 dB and rarely exceeded 3 dB in any subject. CONCLUSIONS: The CDD measured for an individual audiometer and the RECD measured for an individual ear can be used to derive a valid estimate of real-ear SPL when it has not been possible to measure this directly.

Acoustic Impedance Tests↗
PubMedDate not supplied

Subtotal ear canal ablation in 18 dogs and one cat with minimal distal ear canal pathology.

A modified technique for performing total ear canal ablations is described. This technique requires less dissection than the standard technique and maintains a portion of the distal vertical ear canal. Subtotal ear canal ablations were performed in 18 dogs and one cat for the treatment of otitis externa or masses of the horizontal ear canal. Animals with otitis externa had minimal involvement of the distal ear canal. Dermatological problems associated with the remaining ear canal and pinnae occurred in eight animals and resolved with medical management. Normal ear carriage was maintained in all animals with erect ears. Further investigation is required before the procedure can be recommended as a treatment for otitis externa not caused by masses or anatomical abnormalities of the horizontal ear canal in dogs with pendulous ears.

Animals↗
PubMed2005

[Congenital external and middle ear malformation-with 62 ears report].

OBJECTIVE: To determine the relationship between external ear malformation and middle ear abnormality, and also the results of surgical treatment. METHOD: Fifty-two cases with external ear malformation (62 ears) was dividied into two groups:the minor group and severe group. All the patients received surgical treatment, 48 ears by transmastoid approach and 14 ears by "direct entrance" approach. RESULT: The middle ear abnormality was minor in minor group,and severe in the patients with severe external ear malformation. In 93.5% cases the hearing threshold improved more than 15 dB in 3 months after operation, and reduce to 85.5% in 3 years follow up. CONCLUSION: The middle ear malformation is corresponding to external ear malformation. The effect of surgical treatment is different according to the degree of malformation and surgical complication.

Adolescent↗
PubMed2006

[Multi-channel cochlear implantation in patients with congenital inner ear malformation accompanied middle ear malformation].

OBJECTIVE: To report the multi-channel cochlear implantation in three patients with congenital inner ear malformation accompanied middle ear malformation, including CI surgery and postoperative outcomes of hearing and speech recovery. METHOD: Multi-channel cochlear implantation surgeries have been performed in three cases with congenital inner ear malformation accompanied middle ear malformation in our hospital from May 1995 to May 2002. The transmastoid approach was performed to the cases with congenital inner ear malformation accompanied middle ear malformation. The postoperative sound field hearing tests were taken to the cases three months after the cochlear implantation. RESULT: Multi-channel cochlear implantation was successfully performed in three cases with congenital inner ear malformation accompanied middle ear malformation. The 27, 28, 32 electrodes were inserted respectively in three cases. The intraoperative "Ozze" occurred in three patients. No severe intraoperative and postoperative complications occurred in three cases. All postoperative hearing thresholds were at 35-40 dBHL. CONCLUSION Multi-channel cochlear implantation could be performed in the cases with congenital inner ear malformation accompanied middle ear malformation through the transmastoid approach. The postoperative outcomes were satisfied.

Child↗
PubMed1993

Otoacoustic emissions in children with normal ears, middle ear dysfunction, and ventilating tubes.

The clinical utility of otoacoustic emissions (OAEs) has been well established in adults. The purpose of this investigation was to determine the efficacy of OAE testing in children. Distortion-product OAE (DPOAE) audiograms, response/growth functions, and transiently evoked OAEs elicited with clicks were measured from the ears of both healthy volunteers, aged 4 to 13 years, and children with confirmed middle ear disorders. These measures established the means and variabilities for DPOAE and noise-floor amplitudes of normal and diseased young ears. Compared with adult emissions, the healthy young ears exhibited greater mean DPOAE and noise-floor amplitudes. In contrast, ears with type B and type C tympanogram patterns showed absent or markedly reduced OAE amplitudes, when compared with emissions measured in their control counterparts. Finally, ears with ventilating tubes exhibited OAE amplitudes lower than amplitudes from healthy ears, but higher than those of the untreated diseased ears. Although these findings imply that using OAEs to test the outer hair-cell reserve of infected ears is problematic, emitted responses provide useful information concerning the normalcy of middle ear function.

Acoustic Impedance Tests↗
PubMed2001

Eosinophils are activated in middle ear mucosa and middle ear effusion of patients with intractable otitis media associated with bronchial asthma.

BACKGROUND: Although patients with intractable otitis media associated with bronchial asthma have extensive accumulation of eosinophils in the middle ear mucosa and middle ear effusion, systematic histological and immunohistochemical studies have not been performed. OBJECTIVES: To clarify the pathogenesis of middle ear diseases, we carried out immunohistochemical studies on middle ear specimens, particularly focusing on the characteristics of accumulated eosinophils. METHODS: Middle ear specimens obtained from eight adult patients and from 17 controls were immunohistochemically stained using monoclonal antibodies against EG1, EG2, mast cell tryptase, IgA and IgE. The concentration of eosinophil cationic protein (ECP) in middle ear effusion samples was also measured. RESULTS: In the asthmatic patients, severe round-cell infiltration was observed in the submucosa and most of the EG1-positive cells were also EG2-positive. In the control patients, the mucosa showed a fibrotic change with a few inflammatory cells, and EG1- or EG2-positive cells were quite few. The expression of IgE was found not only on the surface of mast cells but also within the plasma cells in the asthmatic patients, and the number of IgE-positive cells was about twice as high as that of mast cells. A significantly higher concentration of ECP was noted in middle ear effusion obtained from the asthmatic patients than that from the control patients. CONCLUSION: Most of the eosinophils in the middle ear mucosa and middle ear effusion were activated, resulting in degranulation and release of ECP, and local IgE production occurs in the middle ear mucosa, indicating that the intractable inflammation is closely associated with IgE-mediated late phase response with eosinophil accumulation.

Adult↗
PubMed1999

[The "ear fever thermometer"--studies of ear thermography].

BACKGROUND: Though rarely mentioned in the ENT literature, the "ear thermometer" has become more and more popular in recent years, not only in hospitals but also in households. These instruments are easy to use, and their infrared technology is said to provide precise measurements. The purpose of this study was to verify these claims. PATIENTS AND METHODS: Infrared thermometers were tested in various conditions, and the results were compared. We assessed the effects of "distending" the outer ear canal, different body positions, and irritation of the ear (slight external otitis, hearing aids, otitis media, etc.). We did not specifically test effects of ear wax, as it had sufficiently been studied in pediatric or anesthesiological papers before (almost no effect, except in cases of occlusion of the auditory canal). RESULTS: Using the ear thermometer we found small but statistically significant differences in febrile patients in different body positions. Irritated ears always showed higher temperatures than the normal contralateral ears. The most significant differences were found in persons lying on one side. The "pillow ear" was found 0.7 degree C (average) warmer than the contralateral ear. CONCLUSIONS: Ear thermometers for estimating the body temperature permit easy and fast measurements. However, they include possible sources of measurement error. This study describes possible errors that the therapists should be aware of to avoid misinterpreting the course of a disease.

Adult↗
PubMed1999

Gas exchange function through the middle ear mucosa in piglets: comparative study of normal and inflamed ears.

The gas exchange function through the middle ear (ME) mucosa was investigated by comparing normal and inflamed ears in an animal model. Piglets were examined (n = 15) because their tympanic bulla closely resembles the human mastoid air cell system. Four untreated ears served as controls. Eleven ears were injected with glycerin into the tympanic bulla to induce inflammation and were studied as inflamed ears. Two respiratory conditions, spontaneous respiration and hyperventilation by a ventilator, were alternated repeatedly. ME pressure was measured intermittently by a tympanometer and blood gas was measured simultaneously. In all four normal ears, both ME pressure and carbon dioxide (CO2) partial pressure in the blood decreased in parallel following alternation of the respiratory conditions from spontaneous respiration to hyperventilation, while both pressure levels increased in parallel when respiration was changed from hyperventilation to spontaneous respiration. This result indicates that there is a gas exchange between the ME and the blood through the mucosa. However, ME pressure change in inflamed ears was limited, though the change in CO2 partial pressure in the blood was the same as that in normal ears. There was a significant difference in the degree of ME pressure change occurring in normal ears compared to that in inflamed ears, suggesting that inflammation of the mucosa reduced gas exchange function in the ME.

Animals↗