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An ear model can be useful in portraying the three-dimensional relationships of the components of the external ear. The role of such a model available as an aid during the carving of a cartilaginous framework in total ear reconstruction is discussed, and a simple method of making an ear model is presented.
49% of 111 patients with sudden hearing loss had pre-existing inner ear damage to a greater extent than would be expected in a population of the same age. The same age-independent hearing loss of inner ear type was seen in 44% of 72 patients with a sudden unilateral isolated vestibular loss. The accumulated occurrence of diseases of the cardial-vascular system, metabolism, and cervical spine is suggested as the reason for the greater extent of inner ear damage with respect of age and the acute disorders in this area. The high proportion of a pre-existing noise deafness in patients (in 38% of men) with sudden hearing loss suggests an increased vulnerability of the inner ear in pre-existing hearing loss.
The mode of inheritance of ear wax type, ear lobe attachment and tongue rolling ability were studied in 77 families with a total of 293 children. The results clearly showed that the dry ear wax type and the attached ear lobe type represent the homozygous state for two pairs of autosomal recessive genes. The evidence for the same being true regarding the lack of ability to roll the tongue was less conclusive in our material, but this could be due to difficulties in communication between the examined individuals and the examiners.
Membranous labyrinth antigen of guinea pigs was prepared. The sera of 33 patients with inner ear disorders of unknown etiology were examined by immunoblotting assay. The autoantibodies against inner ear antigen were found in patient's sera (30.3%). This indicated that the autoimmune activity may play a role in the development of some cases of these diseases. The detection of autoantibodies to inner ear antigen will be of great value to further study on the action of autoimmunological factor contributing to inner ear disorders of unknown etiology.
Forty-one patients of autoimmune inner ear disease were examined with the clinical audiometry and immunocytochemical method. The results showed that there were sensorineural hearing loss in all patients. Serum immunoglobulins (IgG, IgA, IgM) elevation in 14 of 41 patients and antibodies against inner ear tissue in 4 of 41 patients were observed. It suggests that there is specific antibody against inner ear in the serum of patients with autoimmune inner ear disease, and this disease may be originated from the cochlea or the retrocochlea. The method of clinical analyses, the standards of diagnosis and the principles of treatment were discussed.
A complete battery of audiometric methods is required for the differential diagnosis of different hearing disabilities (including puretone audiometry, impedance, stapes reflex, speech audiometry, brainstam evoked response audiometry, otoacoustic emissions, etc.). In many cases, a comprehensive diagnosis is not possible. Here we describe a new technique based on a laser-Doppler vibrometer that has the potential for non-invasive diagnosis not only middle ear disease but also cochlear pathologies. Disturbance of cochlear function can be ascertained because the input impedance of the cochlea acts as a mechanical load on the middle ear and therefore influences motion of the umbo. In the present study vibration of the umbo and eardrum were measured with a commercially available laser-Doppler vibrometer coupled directly into a standard surgical microscope. The use of the microscope allowed non-invasive measurements of vibrations without having to introduce reflecting material onto the tympanic membrane. Sound pressure was measured with a calibrated probe microphone placed near the tympanic membrane. The displacement response and the specific acoustic impedance of the umbo were calculated from the velocity and sound pressure measured. For normal hearing subjects, the amplitude of the umbo's displacement for frequencies from 0.1 kHz to 1 kHz was 1 nm at 60 dB SPL and decreased with a slope of 6 dB/octave for frequencies between 1 and 5 kHz. A strong correlation was found between the specific acoustic impedance of the umbo and hearing thresholds for hearing-impaired subjects (having otosclerosis or sensorineural hearing losses). The frequency response of the umbo proved to be a means for evaluating the function of both the middle ear and the cochlea under pathological conditions. The measurement technique described is also suitable for intraoperative investigation of the frequency response of the opened middle ear, as well as for the in situ frequency response of partial and total ossicular replacement prostheses.
With the aid of a mechanical middle ear model (MMM) the sound transmission properties of different middle ear implants were investigated. Input of the MMM involved a broad-band signal from 100 to 5000 Hz that was supplied by a miniaturized loudspeaker. Displacement of an artificial stapes footplate was measured by a fiberoptic probe. The transfer functions of four different total ossicular replacement prostheses (TORPs) of different materials and shapes were compared. Three of the devices revealed similar transfer functions which corresponded to the typical curve of the normal middle ear. One of the prostheses demonstrated a high-frequency deterioration of approximately 5 dB. This effect was explained by a 3- to 6-times higher mass of the implant when compared to the others. Altogether, the weight of the prosthesis seems to have the most marked impact on sound transmission to the inner ear, whereas stiffness of the implant itself is less crucial as long as it can be regarded as a rigid body.
We wondered how many women had experienced a sensation of fullness in the ear during pregnancy. To address this question, data were obtained from a group of healthy women who attended the gynaecology clinic in our hospital as pregnancy cases between February 1995 and January 1998 and who volunteered to participate in our study. A control group was drawn from healthy female co-medical staff members of our hospital who had never been pregnant. The data used for comparing the two groups were taken from a questionnaire about ear problems that was presented to all subjects. The results suggest that ear problems may be increased in pregnancy, particularly for hypotensive pregnant women. However, even for pregnant women complaining of ear problems, pure-tone audiometry and impedance audiometry showed normal hearing in all cases. Furthermore, these women's complaints resolved completely on delivery of their babies.
OBJECTIVE: To determine the efficacy of Burow's solution as an otologic preparation for the treatment of chronic ear infection. STUDY DESIGN: Two studies were included: 1) a prospective clinical study and 2) a laboratory study on antibacterial and antifungal effects. SETTING: A private otology practice and a laboratory study. PATIENTS: Fifty-eight patients with refractory otorrhea. INTERVENTION: Diagnosis by otoscopy, audiometry, and bacteriology. METHODS: Burow's solution was mixed in solutions with four organisms: methicillin-resistant Staphylococcus aureus, penicillin-resistant Streptococcus pneumoniae, Candida albicans, and Aspergillus. Soon after Burow's solution was mixed in the solutions with organisms, and 5, 10, and 20 minutes thereafter, the mixtures were cultured on agars. The numbers of the bacterial or fungal colonies were counted to evaluate the effect of Burow's solution. MAIN OUTCOME MEASURES: Changes in the clinical findings of the ears, the symptom of otorrhea, and side effects were assessed. RESULTS: Thirty-five (70%) of the 50 ears assessed were "cured" and 10 (20%) ears assessed were "improved." No significant side effect was observed. Regarding the laboratory study, the four organisms disappeared within 20 minutes after Burow's solution was mixed. CONCLUSION: Burow's solution was considered to be an effective otologic preparation.
The permeability of the round window membrane for Salmonella typhimurium-derived endotoxin was examined with use of a total of 33 chinchillas. One milligram of each endotoxin was instilled into the tympanic cavities via the superior bullae. The endotoxin activities in middle ear effusions (MEEs), perilymph, and sera were determined by limulus amebocyte lysate assay. Endotoxin was detected in perilymph on the inoculated side by 12 hours after endotoxin instillation and persisted for up to 3 weeks. Endotoxin level peaked at 24 to 48 hours postinstillation, and it steadily declined afterward. This result suggests that the maximum penetration occurred during the active inflammatory stage. Histologic evidence demonstrated remarkable pathologic changes in the inner ear, including bleeding and inflammatory cell recruitment, mostly in the perilymphatic spaces (eg, scalae tympani, scalae vestibuli, spiral ligament), strial swelling, and sensory cell degeneration. This result suggests that endotoxin present in the middle ear can permeate the round window membrane, causing inner ear tissue damage in this animal model.
Hearing impairment is a major public health problem in Nepal. The present service delivery, however, is mainly hospital based and is limited to large towns. Those people residing in rural areas lack many basic needs including ear care services. The collaborative community volunteer-based ear care pilot programme implemented in Banke, Nepal aims to reach out to those rural areas by establishing sustainable primary ear care services, empowering and utilizing local resources. The focus of the programme is to promote multi-sector improvement in sanitation, nutrition, immunization, breast-feeding and timely care and support to ear patients to help prevent hearing impairment mainly from the sequelae of otitis media.
Otitis media is a common problem, often with simple, minimally invasive solutions; however, a small subset of patients progress to chronic disease despite provision of standard therapies. The flexible approach to tympanoplasty is a prudent consideration for patients with chronic otitis media, especially children. This article discusses the findings and implications of silent otitis media, interactions of the middle ear and inner ear, and obstructive sites in the middle ear cleft. Tympanoplasty by the flexible approach is described in the context of these findings.
This study examined the effect of monaural middle ear destruction on auditory responses to sound direction in the inferior colliculus (IC) of the laboratory mice, Mus musculus. Monaural middle ear destruction was performed on juvenile and adult mice (the experimental mice). Auditory response properties of neurons to ipsilateral and contralateral sounds (I-40 degrees and C-40 degrees ) were examined in the IC ipsilateral to the intact ear 4 weeks later. IC neurons of control mice had higher minimum thresholds (MTs), larger Q(n) (Q(10), Q(30)) values but smaller dynamic ranges at I-40 degrees than at C-40 degrees. These direction-dependent response properties were not observed for IC neurons of experimental juvenile and adult mice. However, Q(n) values of IC neurons were significantly smaller in experimental juvenile than in control and experimental adult mice. Normal tonotopic organization in terms of positive correlation between recording depth and best frequency (BF) was observed in the IC of control and experimental adult mice at both sound directions but not in the IC of experimental juvenile mice. A positive correlation of increasing MT with BF was only observed for IC neurons in control mice but not in both experimental mice. Possible mechanisms for these different response properties are discussed.
The semi-dominantly inherited mouse mutation pardon (Pdo) was isolated due to the lack of a Preyer reflex (ear flick) in response to sound from a large-scale N -ethyl- N -nitrosourea (ENU) mutagenesis programme. Dissection of the middle ear revealed malformations in all three ossicles, rendering the ossicular chain incomplete. Hair cell counts in the apical turn of the organ of Corti revealed a significant 22.7% increase in the number of outer hair cells. Raised compound action potential thresholds in Pdo/+ mutants suggested a combined sensorineural/conductive hearing loss. We show that a missense mutation in the homeobox gene Emx2 is responsible for these defects, identifying a new function for this gene in the development of specific structures in the ear.
The recent fad of high ear piercing in the pinna has led to an increased incidence of auricular chondritis, which leads to dissolution of the cartilage and residual ear deformity. The typical postpiercing chondritis deformity presents as a structural collapse of the superior helical rim, scaphal cartilage, and the adjacent antihelix. The skin envelope is usually preserved, but it may be scarred from the infectious process and from previous drainage incisions. In the present article, the authors present a systematic approach to reconstruction of these acquired ear deformities. Careful assessment of the residual tissue is requisite to planning and appropriate reconstruction. The greater the cartilage loss, the more structural support is required to expand the skin envelope to its normal size and shape. The choice of cartilage donor site is made on the basis of the size of the defect and may include ipsilateral or contralateral conchal cartilage, bilateral conchal cartilage, or costal cartilage. Redraping of the carefully dissected skin and fixation of the flaps to the newly reconstructed cartilaginous framework usually provide sufficient soft-tissue coverage. A temporal-parietal fascial flap is preserved for the rare cases of extensive full-thickness skin loss or badly damaged and scarred auricular skin.
Patients with facial palsy and middle ear disease, which may be chronic but clinically occult, may have a cholesteatoma with extension medially along the facial canal. In two patients, axial computed tomographic (CT) scans demonstrated involvement of the medial petrous bone. Patients with vertigo and chronic middle ear disease may have a cholesteatoma with a "fistula" between the middle and inner ears. Although the fistula usually involves the lateral semicircular canal, the cholesteatoma may pass through the oval window. In two patients, coronal CT scans showed extension to the oval window in one and through it in the other.
The position of the drum of 84 atelectatic ears, of patients 5 to 79 years old, was examined with the help of the operating microscope at different times of the day. All ears were found to be atelectatic during the daytime, yet on the patients' awakening in the morning, 37.73% of the drums of the adolescents' and adults' ears were found to be inflated, usually even hyperinflated. None of the children showed an inflated eardrum in the morning. All eardrums that were inflated in the morning returned to their original atelectatic position within an average of 54.56 minutes after awakening. This observation illustrates another fluctuating aspect of the atelectatic condition.
Based on examination of 80 adult men with unilateral microtia the authors examined the relationship between the affection of the ear lobe, middle ear and face. The revealed significant relations were due solely to subjects with the most severe or with the slightest affection. Correlation coefficients therefore do not characterize relations in the majority of patients and their magnitude is influenced by the ratio of marginal variants of the anomaly in the group. The calculation of the relationship for the entire range of variation of the defect thus is useless. These findings may have a more general validity. They are consistent with the experimental evidence on a haematogenic origin of branchiogenic defects and assumptions derived from this hypothesis. Facial asymmetry is a prognostically important sign for the estimation of the extent of damage of the middle ear.