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At least 1,099 records · Page 61Linked to original sources
PubMed2006

[Effects of different surgical techniques for otosclerosis].

OBJECTIVE: To compare the effectiveness of three surgical techniques for otosclerosis. METHOD: Retrospective analysis was made of patients with otosclerosis who had received surgical treatment during 1993-2005. There were totally 70 patients (76 ears) in which 30 patients (33 ears) underwent total stapedectomy with original stapes, 24 patients (27 ears) underwent small fenestra stapedotomy with Teflon piston artificial stapes and 16 patients (16 ears) underwent stapes mobilization or elevation. Both the hearing results including closure of postoperative air-bone gap and change of postoperative bone conduction threshold at different frequencies and percentages of postoperative vertigo control are compared statistically among three general groups and among two subgroups(stapes mobilization group with 5 cases/ 5 ears and stapes elevation group with 11 cases/ 11 ears). RESULT: There were no statistically significant differences in postoperative speech pure tone average threshold in closing air-bone gap among three groups. Compared with ears treated by otal stapedectomy with original stapes, ears treated by small fenestra stapedotomy and stapes mobilization or elevation, more decreased air-bone gap and lower rates of post-operative sensorineural hearing loss (SNHL) and dizziness at high frequencies were found. CONCLUSION: Although the acceptable effects were found in 3 groups, the better hearing threshold at high frequencies and lower incidence of complications can be obtained in patients with otosclerosis underwent small fenestra stapedotomy and stapes mobilization or elevation. It is suggested that small fenestra stapedotomy with Teflon piston artificial stapes is an ideal surgical treatment for otosclerosis.

Hearing Loss, Sensorineural↗
PubMed2001

[Labyrinthine fistula caused by chronic suppurative otitis media].

OBJECTIVE: To study the clinical feature and surgical management of labyrinthine fistula caused by chronic suppurative otitis media (CSOM). METHOD: A retrospective study of 450 patients with CSOM who underwent radical mastoidectomy between the years 1992 to 1999 in Department of Otolaryngology, Xijing Hospital was conducted. RESULT: 20 patients (4.4%) with labyrinthine fistula caused by CSOM were found. The average history of ear drainage was 22 years, 18 patients (90%) had subjective hearing loss, and 13 patients (65%) had dizziness. The fistula test was positive in 9 patients (45%). 2 patients had anacusis in the affected ear. The preoperative pure tone average for bone conduction thresholds was less than 30 dB in 11 patients, between 31 and 50dB in 3 patients, and more than 51 dB in 4 patients. The ears with a positive fistula test had worse preoperative hearing than those with negative test (P < 0.01). The fistula was detected by CT in 2 of 9 patients. Cholesteatoma was present in 18 patients (90%) and granulation tissue was present in 2 patients (10%). The lateral semicircular canal was the site of labyrinthine fistula. The lesion at the site of fistula was completely removed in 17 patients and exteriorized in the remaining 3. CONCLUSION: There are no reliable methods at present for preoperative diagnosis of labyrinthine fistula, ultimately, the most reliable way to identify a fistula is during surgery. The method of manipulation of labyrinthine fistula is based on the concrete conditions of fistula and patient.

Adult↗
PubMedDate not supplied

A longitudinal study of the association between tooth loss and age-related hearing loss.

The purpose of this study was to investigate cross-sectional and longitudinal associations between hearing acuity and tooth loss in 1156 US veterans taking part in the Veterans Affairs' Normative Aging (NAS) and Dental Longitudinal (DLS) Studies in the Boston, MA, area. The mean age was 48 years (SD = 8.9), 5.3% were edentulous, and 15.4% had < 17 teeth at baseline. Hearing acuity was determined by puretone, air- and bone-conduction audiometry, and speech discrimination tests at triennial examinations over a 20-year follow-up period. Hearing decline was defined as a change from baseline in the average puretone air-conduction thresholds of > or = 20 dB at 0.25, 0.5, 1, 2, 3, 4, 6, and 8 kHz. The explanatory variables of interest were change since baseline in dentate status (cut points at < 1, < 17, and < 20 teeth), and in the number of teeth lost (linear). Linear and logistic regression models--which controlled for baseline audiological status, age, air-bone gap, and otoscopic examination at current visit--showed that subjects who went from having > or = 17 to < 17 teeth had 1.64 times (95% CI, 1.24-2.17) as high odds of having hearing decline as those with no change in their dentate status. For every tooth lost since baseline, there was a 1.04 times as high odds (95% CI, 1.02-1.06) for hearing decline, when additional baseline and time-varying covariates were taken into account in the model.

Adult↗
PubMed1995

Increased bone ingrowth distance into lipid-extracted bank bone at 6 weeks. A titanium chamber study in allogeneic and syngeneic rats.

In previous rabbit chamber experiments, lipid extraction has been shown to increase bank bone incorporation, as measured by scintimetric activity at 3 weeks. In the present study, the new bone ingrowth distance was measured by histomorphometry at 6 weeks using a titanium chamber model in rats. By insertion into bilateral bone conduction chambers, frozen grafts were compared with grafts that had been processed by lipid extraction. To evaluate the effects of lipid extraction further, the group of 26 rats was divided into three subgroups according to MHC haplotype, namely a heterogeneous group (outbred Sprague-Dawley rats), a mismatched group, and a syngeneic group. In the total material, defatted grafts showed a 58% greater new bone ingrowth distance and a 31% higher scintimetric activity over controls. The effect of defatting was not shown to be due to immunologic factors. In general, rats with a lower capacity to incorporate bone grafts showed a larger positive effect of defatting.

Analysis of Variance↗
PubMed2006

Influence of gain of function epithelial chloride channel ClC-Kb mutation on hearing thresholds.

Hearing depends on functional ClC-K-type chloride channels composed of barttin with ClC-Ka or ClC-Kb. Loss-of-function mutations of the barttin gene BSND or of both, the ClC-Ka gene CLNKA and the ClC-Kb gene CLNKB lead to congenital deafness and renal salt wasting. Recently, we identified the gain-of-function mutation ClC-Kb(T481S) which is associated with increased blood pressure. To explore the impact of ClC-Kb(T481S) on hearing, healthy volunteers (n=329) and individuals suffering from tinnitus (n=246) volunteered for hearing tests (n=348) and genetic analysis (n=575). 19.1% of the individuals were heterozygote (ClC-Kb(T481S)/ClC-Kb) and 1.7% homozygote carriers. Pure tone average hearing threshold (PTAt) for air conduction was significantly (p<0.033) lower in ClC-Kb(T481S) carriers (13.2+/-1.2dB) than in wild-type individuals (17.1+/-0.9dB). The prevalence of ClC-Kb(T481S) carriers was significantly increased (29.7%) in individuals with PTAt<15dB (p<0.05) and significantly decreased (13.2%) in individuals with PTAt>30 dB (p<0.017). The difference was largely due to the female population. Bone conduction was less affected pointing to an effect of the mutation on middle ear function. Tinnitus tended to be more frequent in ClC-Kb(T481S) carriers, a difference, however, not statistically significant. In conclusion, hearing thresholds are slightly lower in carriers of ClC-Kb(T481S), i.e., the gain-of-function polymorphism ClC-Kb(T481S) exerts a subtle but significant protective effect against hearing loss.

Adult↗
PubMed2004

[Development and evaluation of a new surface treatment method for titanium alloy implants].

We developed and evaluated a new method of titanium surface treatment for direct bone fixation of implants. This method consists of hydroxyapatite (HA) flame coating onto a porous titanium surface which is arc-sprayed with pure titanium material in argon gas at atmospheric pressure. The surface roughness of the porous layer was 360 μm, Rmax, and showed higher resistance to blast erosion in comparison with the conventional low-pressure plasma-sprayed porous layers of titanium. The thickness of the HA layer was between 20 and 40 μm considering the balance of bone conduction effect of HA and the possibility of mechanical detachment of the layers from the porous titanium. Short-term animal tests showed excellent results. This new surface treatment method was applied to cementless total hip joints which were used clinically. The results obtained from observations of the retrieved specimens show that the thickness of the HA coating layer is sufficient for the new bone formation after implantation. It was concluded that the new surface treatment method for titanium alloy implants is effective and successful for direct bone fixation.

Alloys↗
PubMedDate not supplied

Relative effective frequency response of bone versus air conduction stimulation examined via masking.

An adaptation of the sensorineural acuity level procedure was employed to obtain thresholds under bone- (BC) vs. air-conducted (AC) white noise masking. For the BC masking condition, a Radioear B71 was placed on one mastoid. An Etymotic ER3 with a foam tip placed in the ear on the same side was used to deliver the pure-tone probe stimulus. This transducer was chosen to approximate the Telephonics TDH-39 earphone response characteristic while reducing occlusion effect. For the AC masking condition, the masker and probe were mixed electrically and delivered to the earphone. Masked threshold data, transformed into frequency response curves, demonstrated greater variance of BC vs. AC response across frequency but less high-frequency roll-off than expected from coupler measurements obtained using an artificial mastoid and 6-cm3 cavity, respectively.

Acoustic Stimulation↗
PubMed1980

[Communicative performance using hearing aids (author's transl)].

By means of a questionnaire the utilization of hearing aids has been investigated in 550 patients who had received their aids in the way being typical for the Federal Republic of Germany, i.e. after being prescribed by the ENT-specialist the hearing aid is fitted by the hearing aid acoustician. Additionally the study aimed to analyze relevant factors influencing the use of hearing aids. 45% of the patients used their aids always, 52% regularly (on special occasions) and 3,1% never. The most common complaints of patients refusing their hearing aid were disturbing noise and unsatisfactory understanding. A relatively better utilization of hearing aids--as compared with the average use of the whole group--was found in children, in patients with a hearing loss of a higher degree or with a conductive hearing loss and in patients wearing aids on both ears or aids having a PC-circuit or a so-called "dynamic compression". Relatively lower utilization was seen in patients being older than 60 years, in patients wearing the hearing aid on the worse ear and in workmen. Further factors related to less regular use were: mild hearing loss and high-tone deafness, bone conductive earphone, eyeglass hearing aid and AVC-circuit. There was no correlation between the hearing aid use and the monosyllable discrimination score.

Adolescent↗
PubMed1975

The effects of radiation therapy on bone growth.

Results of a study of the effects of external irradiation on growing bone conducted at Stanford University School of Medicine are presented together with a review of the literature. Standing and sitting heights of 29 children receiving more than 3,500 rads of megavoltage radiation to the spine and 15 children receiving less than 2,500 rads were compared with those of 15,000 normal children. Retardation of spinal growth was seen in children irradiated during the periods of most active bone growth, i.e., under 6 years of age and during puberty. Correlative radiographic findings similar to those seen with orthovoltage therapy were seen in the high-dose group but not in the low-dose group.

Adolescent↗
PubMed1992

Tissue-integrated implants in children.

The aim of this study is to present our clinical experience with tissue-integrated extra-oral implants in children. Thirty consecutive cases of children with a total of 59 standard titanium fixtures inserted in the temporal bones and used as bone-anchorage for auricular epistheses (14 cases) and hearing aids (16 cases) were studied. The surgical procedure is performed in two steps and involves an extremely gentle handling of the soft tissue and bone. The patients were followed with regular check-ups for an average of 40 months after hearing aid/prosthesis fitting. The fixture survival rate was 96.6% for the whole group. The hearing aids had a reaction-free skin penetration in 91.67% of the postoperative observations and the prostheses had a reaction-free skin penetration in 75.00% of the postoperative observations. It is concluded that the use of 'osseointegrated', implants in carefully selected cases, in children, appears to be a reliable method for bone anchorage of epistheses and bone conduction hearing aids. A close follow-up and control of this patient category is especially important with respect to the long-term results.

Adolescent↗
PubMed1989

Clinical role of informal tests of hearing.

Clinical tests of hearing are regularly used in adults but their role, now that pure-tone audiometry is almost universally available, has not been evaluated by modern methods of analysis including sensitivity and specificity. Free-field voice testing was carried out in 101 patients and the Rinne tuning-fork test in a different group of 127 patients prior to clinical or audiometric evaluation. The results were subsequently compared to air and bone conduction pure-tone thresholds assessed using rigorous standards. Depending on the audiometric definition as to what constitutes a hearing impairment, the sensitivity of free-field voice testing to identify such an impairment because of an inability to hear a whispered voice at two feet (60 cm.) was 86 per cent or better with the specificity being in the region of 90 per cent. In the Rinne test the 256 Hz fork was superior to the 512 Hz fork (p less than 0.05) and the loudness comparison method superior to the threshold decay method (p less than 0.01) in detecting an air-bone gap. Combining the responses to the two forks did not improve the results. The Rinne test with the 256 Hz fork will identify correctly 48 per cent of individuals with a 15 dB, 69 per cent with a 20 dB, 87 per cent with a 25 dB, and 95 per cent with a 30 dB conductive impairment. In all instances the specificity is greater than 90 per cent.

Audiometry, Pure-Tone↗
PubMed1997

[Ultramicrostructure study of artificial bone composite with high biological induction in repairing bone defect].

The scanning electric microscopy (SEM). X-ray energy graph and Ca, P contents analysis were adopted in studying the mechanism and superiority of two different composite artificial bones (HA-bBMP-Co and HA-Co) to repair segmental bone defect in rabbits. The results indicated that HA-bBMP-Co had a double effects of bone induction and bone conduction. No difference of P content in two weeks after reconstructive surgery was found, but in other periods, there was an obvious difference in Ca and P content between HA-bBMP-Co group and HA-Co group (P < 0.05).

Animals↗
PubMed1988

The styloid process in ossicular chain reconstruction (a pilot study).

Our pilot study reports twenty-six cases of resolved chronic otitis media in which the human, cadaveric styloid process was used as an ossicular graft material. A maximum follow-up of one year is presented in this paper. There was no extrusion or rejection of the styloid processes. Hearing improvement with a closure of the air-bone gap to within 10-15 dB. of the pre-operative bone conduction was found in most cases. So far the styloid process has proved to be an ideal ossicular graft though the long-term results are yet to be seen.

Bioprosthesis↗
PubMed2003

Could the presence of a Carhart notch predict the presence of glue at myringotomy?

The Carhart notch is a dip in the bone conduction at 2000 Hz without a corresponding dip in the air conduction. The main objective of this study was to establish how reliable is the presence of the Carhart notch in a preoperative audiogram in predicting the presence of glue at myringotomy. A prospective study has been carried out in 50 children presenting with glue ear to find out the association between the Carhart notch and the presence of glue at myringotomy. Children were seen before the operation and an audiogram and tympanogram were carried out. Myringotomy was carried out in 95 ears and the presence or absence of glue was recorded. The significance of the air-bone gap and the type of tympanogram in predicting a middle ear effusion were also examined. The audiograms of 37 ears showed a Carhart notch; of these, 36 ears were noted to have glue ear. The correlation between the presence of a Carhart notch in the preoperative audiogram and the presence of glue at myringotomy was found to be significant (P < 0.001) (chi-square test). Using the decision rule that the presence of a Carhart notch predicts the presence of glue, the following operating characteristics were determined: correct, 83 ears (87.4%); false positive, one ear (1.1%); false negative, 11 ears (11.6%). The presence of a Carhart notch was found to be a strong predictor of the presence of glue at myringotomy.

Acoustic Impedance Tests↗
PubMed2002

Two uncommon uses of Bio-Oss for GTR and ridge augmentation following extractions: two case reports.

Bio-Oss is natural bovine bone mineral, which has the property of bone conduction. It is recommended to be used in two- or three-walled bony defects with an ample supply of pleuripotential cells. Two cases are reported. The first was an intentional replantation, because of previous trauma, of a hopeless tooth affected with severe periodontitis. The tooth was replanted after complete elimination of granulation tissue. Bio-Oss, together with a guided tissue regeneration (GTR) membrane, was used to enhance periodontal regeneration. After 2 years of follow-up, the replanted tooth was quite stable. In the second case, Bio-Oss, together with bone taken from the retromolar area, was used in a sinus lift grafting procedure after the removal of two supernumerary teeth from the floor of the maxillary sinus. Four months after grafting, an orthodontic treatment was applied to move the two adjacent teeth through the grafted site and align them in the proper position. The clinical results of the two cases were satisfactory.

Adolescent↗
PubMed2002

Effect of middle-ear effusion on otoacoustic emissions.

Because otoacoustic emissions (OAEs) are transmitted from the cochlea to the ear canal via the middle ear, the transmission properties of the middle ear directly influence OAEs' characteristics. In general, middle-ear effusion (MEE) reduces measured emission amplitudes and sometimes eliminates the response entirely. The purpose of this study was to establish the relationship between the conduction of the middle ear and OAEs' properties and to elucidate the effect of middle-ear effusion on detecting OAEs. Spontaneous otoacoustic emissions (SOAEs), transiently evoked otoacoustic emissions (TEOAEs) and distortion product otoacoustic emissions (DPOAEs) were recorded from 44 normal ears and 32 ears with middle-ear effusion. DPOAEs were collected in two basic forms consisting of distortion product audiograms (DP grams) and input-output (I-O) functions, elicited by two primary tones F1 and F2 and varying geometric mean frequencies between 1-6 kHz. The results of air and bone conduction hearing levels in pure tone audiogram were also analysed. In 21 ears out of 32 otitis media with effusion (OME) ears, SOAEs were absent. In the 28 ears with middle-ear effusion, the response and wave reproducibility were diminished, and in the 17 ears with middle-ear effusion, the DP gram was diminished or eliminated. In particular, I-O function curves at 3 kH and 4 kHz were diminished by the primary tones of 45 and 55 dB under the condition of MEE. The SOAEs, TEOAEs and DPOAEs (DP gram and I-O function curve) are highly reliable and useful tests for monitoring changes in middle-ear condition in children with OME and in predicting the course of OME.

Audiometry, Pure-Tone↗
PubMed2003

Hearing loss in patients with nasopharyngeal carcinoma after chemotherapy and radiation.

In light of the possible adverse effects of radiation on hearing, we conducted a study to evaluate the long-term sensorineural hearing status following radiotherapy (RT) in patients suffering from nasopharyngeal carcinoma. Audiologic examinations were performed at regular intervals before and after RT. We also analyzed the effects of age, chemotherapy, pre-RT hearing status, and post-RT otitis media with effusion (OME) on post-RT hearing change. A total of 150 patients (261 ears) were enrolled in this study and followed up for a mean of 43.8 months. After RT, 8.9-28.8% of ears had at least a 10 dB loss in bone conduction threshold at speech frequency, which was defined as an average of hearing threshold at 0.5 kHz, 1 kHz, and 2 kHz, while the percentage was 18-34.2% at 4 kHz. Patient age was related to these changes at speech frequency, and the presence of post-RT OME was related to significant loss at both speech frequency and 4 kHz. Pre-RT hearing status and chemotherapy did not influence hearing change. To sum up, sensorineural hearing loss began as early as after completion of RT. Early changes may be transient, but the effect of radiation on hearing tended to be chronic and progressive.

Adolescent↗
PubMed2003

Intracerebral abscess after abutment change of a bone anchored hearing aid (BAHA).

OBJECTIVE: Brain abscesses are life-threatening and sometimes difficult to detect. A brain abscess after placement, manipulation of a bone anchored hearing aid, or a periauricular implant for fixation of an ear prosthesis has never been reported in the literature. PATIENT: A 42-year-old man suffered from a right-sided temporodorsal brain abscess after change of a bone anchored hearing aid abutment. The fixture itself had been inserted 8 years before without any complications in the peri- or postoperative period. A CT-guided puncture of the abscess could be performed via the screw-hole in the temporal bone after removal of the fixture, and the patient was treated with antibiotics. RESULTS: The outcome of the procedure was good without neurologic deficits for the patient. CONCLUSION: The insertion of periauricular screw implants bears the risk of meningeal lesions as well as a small risk of purulent intracranial and intracerebral complications perioperatively or in the context of later manipulations. Minimally invasive therapy of such brain abscesses can be performed by removal of the foreign body, CT-guided puncture, and antibiotic medication.

Adult↗