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PubMed2005

Comparing neurootological complaints in patients at the end of their professional lives (51-60 years) with those during the first phase of retirement (61-70 years).

Geriatrics defines the branch of medicine that treats all problems peculiar to old age and the aging, including the clinical problems of senescence and senility. In the full chain of years of the human life, a special period is humans' last decade of professional life (i.e., 51-60 years) and their first decade of retirement (i.e., 61-70 years). For this study aimed at comparing neurootological complaints of persons in this period of their lives, we examined large samples of European neurootological patients: Group A consisted of 1,965 persons aged 51-60 years, and group B consisted of 1,032 persons aged 61-70 years. Of the 11 vertigo and nausea symptoms evaluated, group A demonstrated 2.68 signs and group B 2.49 signs per individual. Acoustic subjective symptoms of tinnitus were exhibited in 55.42% of group A patients, and hearing loss was present in 63.92% of these patients. In group B, 52.62% of patients exhibited tinnitus, and 68.31% of patients had hearing loss. Our experimental neurootometric investigations exhibited the following rates of abnormal test findings in group A: butterfly calorigrams, 71.86%; stepping craniocorpography, 72.01%; and pure-tone audiometry of bone conduction, 37.66% in the right and 47.07% in the left ear. Among group B patients, abnormal test findings were noted as follows: butterfly calorigrams, 69.86%; stepping craniocorpography, 74.03%; and pure-tone audiometry of bone conduction, 44.57% in the right and 55.43% in the left ear.

Aged↗
PubMed2003

Effect of lacunocanalicular architecture on hydraulic conductance in bone tissue: implications for bone health and evolution.

Bone tissue health depends largely on efficient fluid and solute transport between the blood supply and cells that are the living component of the tissue. We hypothesized that the lacunocanalicular hydraulic network, which is defined by the pericellular fluid space that is common to all bone tissue, is optimized to transport fluid and solutes between the blood supply and bone cells. An analytical study was carried out to evaluate the effect of osteonal architecture, including the osteon diameter, number of annular lamellar regions, and number and length of canalicular channels, on fluid transport between the blood supply and bone cells. On the basis of this analysis, we conclude that osteon size is limited to the distance over which fluid and solutes can be transported efficiently between the blood supply and cells. This analytic model suggests that hydraulic conductivity is highest in lamellar regions closest to the Haversian canal (HC) and decreases with increasing distance from the blood supply, reaching a plateau after the fifth lamella (169 micro m radius). Furthermore, an increase in the diameter of the HC, or a decrease in the length of canaliculi, reduces the hydraulic conductivity within the lacunocanalicular network. Applying the principle of minimal expenditure of energy to this analysis, the path distance comprising five or six lamellar regions represents an effective limit for fluid and solute transport between the blood supply and cells; beyond this threshold, hydraulic resistance in the network increases and additional energy expenditure is necessary for further transportation. This suggests that transport is optimized to meet metabolic demands concomitant with a minimal expenditure of energy. This fundamental new insight into bone structure and physiology may provide a new basis of understanding for tissue engineering, bone physiology in health and disease, and evolutionary biology.

Animals↗
PubMed1985

Histologic variants in otosclerosis.

A study of 164 temporal bones with otosclerosis revealed stapes fixation in 123. Large lesions (4 mm or larger) were characterized by involvement of the cochlear endosteum, increased cellular activity, and bone resorption. Anatomical sites of predilection were: 1. anterior to the oval window, 2. margins of the round window, and 3. apical-medial wall of the cochlea. Two of the five ears with cochlear otosclerosis were from a patient with severe bilateral hearing loss. The size, cellular activity, and location of otosclerotic lesions showed no correlation with the magnitude of sensorineural hearing loss. Subjects over 69 years of age had greater bone-conduction losses than age-matched controls. Nine ears showed occlusion of the round window niche.

Adult↗
PubMedDate not supplied

[The use of extraoral osteointegrated implants in otolaryngology and maxillofacial surgery in children].

We present our clinical experience with extraoral osteointegrated implants in children. We treated a total of a twenty cases. Seventeen were cases of auricular ephitesis, and in six of them we also inserted a bone conduction auditory prosthesis. In three cases we inserted an orbital ephitesis. Two operations are necessary to place the osteointegrated implants in the temporal and orbital regions respectively. We made a follow-up study of these patients for approximately two years, and we present the resulting statistics, and complications that we encountered. We conclude that osteointegrated implants in carefully pre-selected children, offer excellent ephitesis setting and a reliable method of installing bone conduction hearing aids.

Child↗
PubMed1996

Vestibular symptoms in otosclerosis--correlation of otosclerotic involvement of vestibular apparatus and Scarpa's ganglion cell count.

Although several histopathologic studies have shown otosclerotic involvement of the vestibular apparatus in patients with otosclerosis, the pathogenesis of vestibular symptoms in otosclerosis remains unknown. A quantitative study of Scarpa's ganglion was performed in 217 temporal bones from 118 subjects with otosclerosis. Review of clinical records revealed an incidence of vestibular symptoms in 11.9% of these subjects. Scarpa's ganglion cell counts in temporal bones of subjects with otosclerosis and vestibular symptoms were lower than counts in temporal bones of subjects with otosclerosis but without vestibular symptoms and those of normal subjects. This difference in Scarpa's ganglion cell counts, adjusted for age, between the group with otosclerosis and vestibular symptoms and a group of normal subjects was highly significant (p = 0.0015), whereas the difference in Scarpa's ganglion cell count between a group with otosclerosis but without vestibular symptoms and a group of normal subjects was not significant (p = 0.53). There was also a significant correlation between elevation of the average bone-conduction threshold and the presence of vestibular symptoms in these subjects (p = 0.041). The endosteum of the perilymphatic space of the vestibule and the endosteum of the canal for the superior vestibular nerve or its cribrose area were the two most common sites of involvement by otosclerosis. However, there was no significant correlation between the presence of vestibular symptoms and otosclerotic involvement of any single site or the number of involved sites. Histologic examination of the vestibular nerve fibers and end organs subjacent to otosclerotic foci demonstrated no obvious degenerative changes. Thus our findings appear to suggest that the vestibular symptoms present in patients with otosclerosis are more common in patients with elevated bone conduction thresholds and are correlated with degeneration of the vestibular nerve, which appears to be independent of the severity of otosclerotic involvement of the vestibular end organs.

Aged↗
PubMedDate not supplied

Correlation of otosclerotic foci and degenerative changes in the organ of Corti and spiral ganglion.

Statistical analyses of histopathologic findings in the cochlea and spiral ganglion of 37 temporal bones with otosclerosis, 12 controls of similar age, and seven controls with normal hearing were performed. In temporal bones with otosclerosis there was significant atrophy of the spiral ligament and stria vascularis in regions with endosteal involvement by otosclerosis, compared with regions without endosteal involvement (P less than .0001). There was more generalized atrophy of the stria vascularis in cochleae with two or more sites of endosteal involvement by otosclerosis than in cochleae with only one site of endosteal involvement (P less than .02), cochleae in temporal bones with otosclerosis but without endosteal involvement (P less than .05), or cochleae of controls of similar age (P less than .007). In addition, there was more atrophy of the spiral ligament in cochleae with two or more sites of endosteal involvement than in cochleae of similar age from the control group (P less than .03). In temporal bones with otosclerosis, there was no significant difference in counts of outer hair cells and density of spiral ganglion cells between regions demonstrating endosteal involvement by otosclerosis and regions without such involvement. However, total outer hair cell counts were lower in cochleae with two or more sites of endosteal involvement of otosclerosis than in cochleae with one site of endosteal involvement (P less than .04), cochleae in temporal bones with otosclerosis but without endosteal involvement (P less than .02), or cochleae from individuals of similar age but without otosclerosis (P = .05). Comparison of the mean bone conduction threshold, as measured in life, in temporal bones with otosclerosis compared with the air conduction threshold in aged-matched controls, demonstrated that only cochleae with two or more sites of endosteal involvement had a mild but statistically significant (P = .05) decrease in hearing. There was no evidence to support the concept that otosclerotic foci without stapedial fixation frequently cause significant degeneration of the cochlea or elevation of bone conduction thresholds.

Adolescent↗
PubMed2004

A long-term study on hearing status in patients with nasopharyngeal carcinoma after radiotherapy.

OBJECTIVE: To study the long-term sensorineural hearing status after radiotherapy in patients suffering from nasopharyngeal carcinoma. STUDY DESIGN: A prospective study of 220 patients (395 ears) with a median follow-up of 36 months. SETTING: A university hospital. PATIENTS: Four criteria were needed. The patient had to have had at least 12 months of audiologic follow-up, no concurrent chronic ear disease, no direct tumor invasion of ear, and no significant sensorineural hearing loss before radiotherapy. INTERVENTION: Pure-tone audiography and impedance audiometry-which were performed before and at the third month after completion of radiotherapy and at a yearly interval thereafter-formed the basis of the study. MAIN OUTCOME MEASURES: The significance level in this study was defined as a bone conduction threshold increase of more than 10 dB between the initial audiogram and those obtained after the completion of radiotherapy. An increase of more than 30 dB was defined as severe loss. RESULTS: Paired t test indicated that the mean bone conduction threshold before and after radiotherapy were significantly different (paired t test, p < 0.05). Logistic regression showed that patient age was related to the significant loss at speech frequency but not to the loss at 4 kHz. The presence of postradiation otitis media with effusion, preirradiation hearing status, and addition of chemotherapy were found to be not influential on hearing change. CONCLUSION: Hearing deterioration may begin as early as 3 months after the completion of radiotherapy. Early change may be transient, but the effect of radiation on hearing tended to be chronic and progressive.

Acoustic Impedance Tests↗
PubMed2000

Perioperative glucocorticoid treatment does not influence early post-laser stapedotomy hearing thresholds.

OBJECTIVE: The aim of this study was to evaluate the efficiency of prophylactic perioperative glucocorticoid treatment during stapes surgery in preventing damage to the inner ear and reducing the frequency of early postoperative complications. STUDY DESIGN: A prospective, randomized, unblinded study design was selected. SETTING: The study was conducted at an academic tertiary referral center. PATIENTS: Ninety-five consecutive patients undergoing erbium:YAG laser-assisted stapedotomy for otosclerosis between 1996 and 1999 were included. MAIN OUTCOME MEASURES: The preoperative minus postoperative (1-4 days and at least 6 weeks) average pure-tone bone conduction thresholds at 1, 2, and 4 kHz were compared in the prednisolone and control groups by the Mann-Whitney U Test. In addition, the occurrences of sensorineural hearing loss of >10 dB, nystagmus, vertigo, and tinnitus were counted and evaluated by use of the Freeman-Halton or Fisher's exact test, respectively. RESULTS: Prophylactic perioperative prednisolone treatment was not able to improve the early postoperative average bone conduction thresholds or reduce the frequency of early sensorineural hearing loss (p > 0.5). The patients who received perioperative prednisolone treatment experienced postoperative vertigo more frequently than did the control patients (p < 0.05). CONCLUSION: Perioperative cortisone prophylaxis for prevention of inner ear damage during stapes surgery is ineffective and is associated with increased postoperative patient discomfort.

Adult↗
PubMedDate not supplied

The effect of middle ear disorders on noise-induced hearing loss.

Two groups of subjects, 50 noise-exposed and 50 non-noise-exposed, both with unilateral conductive hearing loss, were studied in terms of the amount of conductive hearing loss and difference in the bone conduction thresholds at 4 kHz between the two ears. The results support the hypothesis that middle ear disorders provide the ear some protection from noise-induced hearing loss.

Adult↗
PubMed1991

[Sensorineural hearing loss in chronic otitis media].

In individuals with chronic otitis media-(COM), mixed hearing impairments are common, but it is unclear whether the raised bone conduction thresholds are a reflection of the pathologic process affecting the middle ear resulting in conductive defect. Charts of 65 patients with unilateral chronic otitis media were reviewed. These were three groups: 1) simple COM 2) COM with granulation, 3) COM with cholesteatoma. In them, the amount of sensorineural hearing loss in the third group was 20.3 dB, which was greater than the other two groups for pure-tone average. The amount of air conduction hearing loss was 66.8 dB, also the highest. In addition, the amount of sensorineural hearing loss was greater than that of normal contralateral ears in all of three groups. These findings suggest that more severe middle ear disease may result in sensorineural hearing loss. Raised bone conduction thresholds in chronic otitis media are considerably more likely to reflect the Carhart effect, rather than disease damage to the inner ear. However, for the majority of subjects, the amount of sensorineural hearing loss was judged not to be clinically significant.

Adolescent↗
PubMed1980

Incus reposition: goblet prosthesis.

A stainless steel goblet shaped prosthesis is used to attach the repositioned incus to the stapes. A two year follow-up was made of the first 116 patients in which the prosthesis was used for ossicular reconstruction. The incidence of extrusion and ankylosis is diminished, and 75% of all cases had closure within 10 db. An additional 20% had closure within 20 db of bone conduction thresholds. Revisions have been less with this technique than with others: 40% of 116 patients had an uncomplicated tympanoplasty; 60% had a tympanoplasty with mastoidectomy. The results are, of course, more favorable in the group without mastoidectomy. Of these, 86% had closure to within 10 db of bone conduction level. These findings suggest that the use of the goblet prosthesis results in improved hearing. These findings conclude that the use of the goblet prosthesis results in better hearing than that obtained with other methods of ossicular chain reconstruction.

Ear Ossicles↗
PubMed2005

Preoperative evaluation of ossicular chain abnormality in patients with conductive deafness without perforation of the tympanic membrane.

OBJECTIVE: To evaluate the usefulness of pure-tone audiometry, tympanometry, and liquid and acoustic reflex (AR) tests in the differential diagnosis of ossicular fixation and discontinuity. DESIGN: A prospective clinical trial. SETTING: Tertiary referral center. PATIENTS: Thirty-nine patients (46 ears) undergoing operations at University of Tsukuba Hospital, Tsukuba, Japan, from 1990 through 2003 for conductive deafness without perforation of the tympanic membrane. Clinical examinations for the preoperative diagnosis included pure-tone audiometry, tympanometry, and liquid and AR tests. We compared the preoperative diagnosis with the surgical findings. RESULTS: Although neither pure-tone audiometry nor tympanometry contributed to the differential diagnosis of ossicular chain abnormality, liquid and AR test results showed a significant difference between fixation and discontinuity of the ossicular chain. With the liquid test, bone conduction at lower frequencies was improved by filling the external auditory canal with water at lower frequencies in cases of ossicular fixation. In contrast to the findings observed in ossicular fixation, no improvement of the threshold of bone conduction was recognized at any frequency in the ears with ossicular discontinuity. In ipsilaterally stimulated AR, the reversed pattern was the most marked at 2000 and 500 Hz in ossicular fixation and discontinuity, respectively. CONCLUSION: Liquid and AR tests are reliable examinations for the differential diagnosis of ossicular fixation and discontinuity.

Acoustic Impedance Tests↗
PubMed2004

[Evaluation of safety on the noise of drills in the tympanoplasty].

OBJECTIVE: To investigate the effect of noise generated by the otologic drills and suctions on the cochlear of the operated and nonoperated ear. METHOD: To examine the noise generated by the different kind of drills and suctions in tympanoplasty, the ND10 Sound Level Meter (Beijing) was used. The bone-conduction thresholds was measured before and one month after operation respectively in both ears. RESULTS: Sound pressure levels for the otologic drills and suctions were 82-106 dB and 71-84 dB, respectively. There was no statistically significant difference between pre-noise and one-month post-noise bone-conduction thresholds in both operated and nonoperated ears. CONCLUSION: It is safety to use otologic drills and suctions for the patients. There is no apparent harmful effect on the function of cochlear in both ears for the noise of using drills and suctions in tympanoplasty.

Evaluation Studies as Topic↗
PubMed1982

Calculation of hearing results after tympanoplasty.

At present there is no universally accepted method for calculating hearing results after chronic ear surgery. In this study the methods most frequently used have been applied to a material of 105 tympanoplasties and compared to each other. In addition a comparison between pre- and post-operative bone conductions (BC) thresholds for calculating post-operative air-bone gaps has been performed using multiple regression analysis. The results lend support to the conclusion that BC thresholds will improve with surgery in successful cases and that the post-operative BC threshold is a closer approximation of the cochlear function than the pre-operative one and consequently should be used for gap calculations. However, until the masking procedures in audiometry are standardized, hearing gain may be regarded as the most satisfactory alternative for describing hearing results as it is based on the air conduction thresholds only. This method requires a careful description of pre-operative air and bone conduction thresholds.

Audiometry↗
PubMed1999

[Otosclerosis surgery: a series of 227 cases. Introduction of CO2 laser].

OBJECTIVES: To evaluate the effects of the size of the footplate opening on the hearing results in surgical treatment of otosclerosis and the use of CO2 laser in this indication. PATIENTS AND METHODS: 190 patients with otosclerosis underwent 227 procedures between 1986 and 1995. Hearing results and symptoms were analyzed to compare the different procedures: 140 stapedectomies, 87 Fisch's stapedotomies, 35 of them with manual perforator, 52 of them with CO2 laser. RESULTS: Air/bone gap closure within 10 dB was obtained in 87, 92 and 97 percent of stapedectomies and in 80, 84 et 90 percent of stapedotomies after 3 months, 1 and 3 years (NS). Bone conduction was improved in 81, 80 et 63 percent of stapedectomies and 87, 97, 60 percent of stapedotomies after the same time (NS). Air/bone gap closure within 10 dB was obtained in 75 and 80 percent of manual perforator stapedotomies and in 84 and 88 percent of CO2 laser stapedotomies after 3 months, and 1 year (NS). Bone conduction was improved in 78 and 96 percent of manual perforator stapedotomies and 95 and 100 percent of CO2 laser stapedotomies after the same time (NS). No facial palsy or prolonged vertigo occurred. There was one case of anucusis following a stapedectomy. CONCLUSION: Although both stapedectomy and stapedotomy produced equivalent air/bone gap closure, reduction of inner ear trauma was noted with Fisch's stapedotomy. CO2 laser technique is a safe procedure, which optimizes the Fisch's stapedotomy.

Adolescent↗
PubMed1992

[Indications and surgical treatment of large middle ear abnormality].

Children with atresia of the external auditory canal should undergo hearing assessment and fitting of a bone conduction hearing aid as early as possible to allow speech to develop normally. Surgery is done between 5 and 6 years of age, guided by high-resolution computed tomography, which provides a more precise diagnosis based on the abnormalities seen. The temporomandibular joint lies more posteriorly than normal due to aplasia or hypoplasia of the tympanic bone, so that the middle ear must be approached through the mastoid, resulting in a less favourable coupling to the middle ear structures. In unfavourable cases bone anchored hearing aids, creation of a meatus for fitting a hearing aid or a bone conduction hearing aid must be considered.

Adolescent↗
PubMed2002

Labyrinthitis in chronic otitis media.

Labyrinthitis is the most frequent complication of chronic otitis media (COM). Retrospective analysis of 1,210 patients operated due to COM was carried out. Circumscribed labyrinthitis was found in 17.2% and deafness in 1.2% of patients. To evaluate the effect of labyrinthitis on bone conduction (BC) we measured BC threshold in a group of 140 patients with unilateral COM without labyrinthitis and in a group of 42 patients with unilateral COM with labyrinthitis. BC threshold of the healthy ear was subtracted from the BC threshold of the affected ear in the same patient to eliminate presbyacusis. There was no significant difference in bone conduction threshold between the patients with circumscribed labyrinthitis and patients with COM without labyrinthitis. The incidence of labyrinthitis was higher in patients with cholesteatoma than in patients without cholesteatoma. Management of labyrinthine fistula is presented.

Adolescent↗
PubMed2006

A prospective study on radiation-induced changes in hearing function.

PURPOSE: To quantitate changes in hearing function after radiotherapy for head-and-neck tumors. METHODS AND MATERIALS: At the Department of Radiotherapy and Radiation Oncology, 32 patients were irradiated for head-and-neck tumors. Three-dimensional treatment planning was applied. Total tumor doses were 30.0-77.6 Gy, local doses to the inner ear (n = 64) ranged from 1.7 to 64.3 Gy. Audiometry was performed before the onset of radiotherapy (RT), at a tumor dose of 40 Gy or at the end of palliative treatment, at the end of curative RT, and 2-6 months post-RT. Assays applied were frequency-specific threshold measurements for air and bone conduction, measurements according to Weber and Rinne, tympanometry and assessment of the stapedius reflex. RESULTS: Age and prior disease significantly decreased, whereas previous or concurrent alcohol consumption significantly increased hearing ability. A significant reduction in hearing ability during RT was found for high frequencies (at 40 Gy) and low frequencies (at end of RT), which persisted after RT. No differences were observed for air or bone conduction. None of the other assays displayed time- or dose-dependent changes. Dose-effect analyses revealed an ED50 (dose at which a 50% incidence is expected) for significant changes in hearing thresholds (15 dB) in the range of 20-25 Gy, with large confidence limits. CONCLUSIONS: Radiation effects on hearing ability were confined to threshold audiogram values, which started during the treatment without reversibility during 6 months postradiotherapy.

Adult↗