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At least 1,603 records · Page 89Linked to original sources
PubMed2007

Congenital aural atresia: review of short- and long-term surgical results.

OBJECTIVES/HYPOTHESIS: To review the short- (<1 yr) and long-term (>1 yr) surgical and hearing outcomes for congenital aural atresia and to analyze the stability of surgical results over time. STUDY DESIGN: Retrospective chart review of 45 patients (54 ears) who underwent surgery for congenital aural atresia during a 5-year period at a tertiary care institution. METHODS: Preoperative and postoperative speech reception thresholds, air-bone gaps (ABGs), and pure-tone averages were compared and further analyzed for outcome stability over time. The complication rate was reviewed and compared with results from similar studies. RESULTS: Approximately 50% of patients achieved a speech reception threshold of 30 dB or better both in the short and long term. The average improvement in ABG was 22 dB, resulting in a postoperative ABG of 30 dB or less in three of four patients. Short- and long-term outcomes were not significantly different. Patients with an intact ossicular chain did not seem to have a significant advantage in hearing when compared with patients with a prosthetic reconstruction prosthesis. We report a low incidence of meatal stenosis compared with other similar reviews and describe surgical modifications that may attribute to this outcome. CONCLUSION: Overall, the mean hearing outcome for this group collectively did not significantly degrade over time and compared favorably with other series. However, there was significant variability among individual patients. The safety of this procedure and the demonstrated hearing improvement makes it a reasonable option in patients with congenital aural atresia with favorable anatomy.

Adolescent↗
PubMed1996

Acoustic assessment of fracture healing. Capabilities and limitations of "a lost art".

The ability of bone to conduct sound was applied clinically over 50 years ago to identify the presence of fresh fractures, although the technique has become a relatively "a lost art" as more sophisticated X-ray and other imaging techniques have been developed. The objective of this report is to challenge clinical orthopaedic surgeons unfamiliar with the technique to explore this simple beside method in the clinical management of fractures. A portable computer-based vibrational analysis device was employed and experiments conducted to objectively evaluate the capabilities of auscultatory percussion techniques. Auscultatory percussion can, with certain limitations, detect the presence of fractures, assess qualitatively the progress of healing, detect delayed or nonunions, and indicate when sufficiently firm continuity has occurred to permit early mobilization or loadbearing. Vibrational assessment is, however, subject to systematic and random errors, and thus cannot always discriminate between the stages of healing in a fractured bone; in addition, various artifacts can lead to significant uncertainty in the diagnosis. Nevertheless, auscultatory percussion is a useful tool in clinical fracture management, and particularly where roentgenographic facilities are inadequate or not available. Computerized vibrational analysis can be used in place of classical percussion/stethoscope methods by those with poor tonal capabilities,or when more objective record keeping is desired.

Auscultation↗
PubMed2002

[Preparation of rhBMP-2/BCB reconstituted bone xenograft and assay of its osteoinductivity].

OBJECTIVE: To investigate a new grafting material of bone xenograft with strong bone inductive and conductive capacity. METHODS: Based on successful clinical application of the reconstituted bone xenograft (RBX), a new xenograft was made by combining recombinant human bone morphogenetic protein-2 (rhBMP-2) with antigen-free bovine cancellous bone (BCB). Sixty male BALB/C mice aged 4 weeks were divided into study group of 30 and control group of 30 randomly. rhBMP-2/BCB was implanted in the left thigh muscle pouch in the study group and BCB in the control group. The mice were sacrificed at 7 d, 14 d and 21 d after implantation. Inductivity of rhBMP-2/BCB was detected by histological observation and biochemical determination of the samples. RESULTS: Histological examination showed that rhBMP-2/BCB induced chondrogenesis on the 7th day, with woven bone formed on the 14th day, and lamellar bone and marrow on the 21st day, while BCB failed to induce chondrogenesis or osteogenesis on the 7th, 14th and 21st days. The alkaline phosphatase activities and calcium content in study group were higher than those in control group with significant difference (P < 0.01). CONCLUSION: rhBMP-2/BCB is an ideal grafting material with strong bone inductive and conductive capacity without evoking immune reaction.

Animals↗
PubMed2001

Results of stapes surgery on patients with osteogenesis imperfecta.

Osteogenesis imperfecta (OI) is a heterogeneous group of connective tissue disorders. The classic triad of blue sclerae, spontaneous fractures and hearing loss is known as the Van der Hoeve and De Kleyn syndrome. Between 1989 and 2000, six patients with OI presented with conductive hearing loss. Five of them proceeded to stapedotomy. All the patients who had surgery had significant hearing gain. None of the patients had any complications. This study presents a higher incidence of spontaneous fractured crura as the cause of the conductive hearing loss than previously reported, and that the presence of a fractured crura with mobile footplate can be anticipated by the presence of a large conductive hearing loss. The pre- and postoperative results are presented and support the view that stapes surgery in OI can have encouraging results, provided the operator anticipates the possibility of a fractured crura and a mobile footplate.

Adult↗
PubMed2003

Rapid maxillary expansion and conductive hearing loss.

The purpose of this study was to evaluate the effects of rapid maxillary expansion (RME) on conductive hearing loss in 35 subjects (21 girls and 14 boys) with an average age of 14 years 6 months. All patients had maxillary constriction with a high palatal vault and a conductive hearing loss. Pure-tone audiometric records were used to determine the hearing levels at four time intervals, namely, before RME, after sufficient midpalatal suture opening was obtained (mean: 18 days), after the retention period (mean: six months), and a final set two years after the retention period. Records were evaluated by the same otolaryngologist. Analysis of variance was used to assess the changes in the hearing level and the air-bone gap. Descriptive statistics were calculated for each subject at each period. The results indicated that significant changes occurred in both the hearing levels and air-bone gaps in both timing and frequency after the active treatment period (P < .001). For most patients (74%), these improvements were maintained two years after active treatment.

Adolescent↗
PubMed2005

[Application of the tragus cartilage ring with perichondrium in open-ended tympanoplasty].

OBJECTIVE: To investigate the effect of the application of tragus cartilage ring with perichondrium in open-ended tympanoplasty and it's long-term results. METHOD: The tympanic membrane perforations were treated by the surgery of open-ended tympanoplasty. The tragus cartilage ring with perichondrium autograft in 38 patients with otitis media were adopted in the operation from 1995 to 2000. After operation,the patients were followed up in 2 weeks, 1 month, 3 months, 6 months, 1 year and 3 years. RESULT: Of 38 cases, 4 failed but the othershealed in one stage. The successful rate was 89.47%. After 2 weeks, among the 4 cases,2 had grafts crannies and 2 cases were infected. But when they accepted the second operation and after a following up of three years, the successful rate was 100%. Grafts were atrophy in 2 cases after 6 months to 3 years. Before the operation the average air conduction hearing was (45.66+/-8.40)dB HL and the difference between bone and air was less to (26.05+/-8.15)dB HL. From 1 months to 3 years after the operation, the air conduction and bone conduction ware respectively (31.58+/-7.45)dB HL and (19.61+/-6.41)dB HL in 1 month, (26.18+/-7.02)dB HL and (12.63+/-7.59)dB HL in 3 months,(23.55+/-7.70)dB HL and (10.79+/-5.52)dB HL in 6 months,and (23.42+/-6.99)dB HL and (11.05+/-5.95)dB HL in 1 years, keeping at limits of (23.95+/-6.69)dB HL and 10.53+/-5.43 dB HL in 3 years. There were significant differences between pre-operation and post-operation in 1 month,and 3 months. But there were no significant differences after operation in 6 months, 1 year, 3 years and 3 months. CONCLUSION: The tragus cartilage ring with perichondrium is of great importance to increase the guality of tympanoplasty and effective rate owing to its reliable technique and material collection.

Adolescent↗
PubMed1996

Long-term follow-up of stapedectomy in children and adolescents.

Otosclerosis presenting in children and adolescents is uncommon. Typically, otosclerosis presents as a slowly progressive conductive hearing loss in the third to fourth decade. Many well-documented studies have demonstrated excellent long-term hearing results with stapedectomy. Although stapedectomy is highly effective, the rare complications may be devastating. Thirty-one patients, 21 years or younger, underwent 40 stapedectomies for otosclerosis at our institution. The average age at surgery was 16 years, with a range of 7 to 21 years. Postoperative results showed an average improvement in air-bone gap of 22 dB. Clinical and audiologic data were collected over a mean follow-up period of 25 years. There was no statistically significant difference in air-bone gap when comparing the immediate postoperative gap (measured 2 months after stapedectomy) with the last gap recorded (mean, 25 years after stapedectomy). Fifty percent of the ears operated on maintained an air-bone gap within 10 dB at the last follow-up, and an additional 40% maintained a 10- to 20-dB gap. There were no significant relationships between demographic or clinical factors and "success" (gap <= 10 dB) or long-term gap closure. Our data demonstrate that stapedectomy is an effective method for closing the air-bone gap in children and adolescents with otosclerosis, and long-term results parallel those of adults, showing maintenance of excellent gap closure. This review represents the largest population with the longest follow-up in children who underwent stapedectomy for the treatment of otosclerosis.

Adolescent↗
PubMed1992

Influence of temperature and foil hardness on interocclusal tactile threshold.

Determinations of interocclusal tactile threshold levels so far have involved neither appropriate psychophysical approaches nor an assessment of the mechanical and thermal properties of the foils used. Twenty subjects (12 females) aged 18 to 50 (mean age 35) were tested for their absolute threshold level (RL). Both the method of limits and the staircase method were applied to determine the active or passive RL. For the active RL assessment, foils of different thicknesses were placed between edge-to-edge opposed incisors during gentle biting. Inner ear receptors of the blindfolded subjects were blocked by broad band noise applied through earphones, because vibrations induced by occlusal contact and conducted through bone might be perceived by these receptors. The foils presented were aluminum (Al), tin (Sn), polyester (PE) and calibrated steel (St) (thickness ranging from 8 to 50 microns) which offer different physical and thermal properties. The range of RL of the group varied between 8 microns for aluminum to 46 microns for polyester for 50% correct assessments. Increasing the foil temperature from room temperature (20 degrees C) to body temperature (35 degrees C) significantly increased the RL for conducting materials (one-way blocked ANOVA). These results indicate that temperature exchange takes place while presenting conducting foils at 20 degrees C (cold stimulus) interocclusally, which influences the RL by activating thermosensitive receptors. The passive RL determination with classical von Frey-hairs resulted in a mean axial RL of 3.0 g. Both psychophysical RL assessments (method of limits, staircase method) gave reproducible and similar results as ascertained by ANOVA. Furthermore, a positive correlation was established between active and passive RL (Pearson correlation test).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1977

[Determination of the impaired ear's frequency selectivity using psychoacoustical tuning curves (author's transl)].

An apparatus for clinical use is described by which simplified psychoacoustical tuning curves can be measured near 500 Hz and near 4 kHz. Data produced by four groups (normal hearing, conductive hearing loss, noise induced hearing loss and degenerative hearing loss) are separately averaged and compared. The first mentioned two groups as well as the third in the low frequency range show good frequency resolution, the others, however, show largely decreased frequency resolution.

Audiometry↗
PubMed2001

Three-year follow-up of the use of transdermal 17beta-estradiol matrix patches for the prevention of bone loss in early postmenopausal women.

OBJECTIVE: A total of 325 of 569 postmenopausal women who were initially recruited into two 2-year, double-blind, placebo-controlled, dose-ranging studies of a matrix transdermal formulation of 17beta-estradiol (Menorest) participated in open-label extensions for a third year. STUDY DESIGN: Those patients originally randomly assigned to receive 17beta-estradiol continued active treatment with dosages of 25, 50, 75, or 100 microg/d, whereas those originally randomly assigned to receive a placebo patch were switched to an active patch of identical size that delivered 17beta-estradiol at 25, 50, 75, or 100 microg/d. Follow-up was conducted, and bone density and other parameters were compared. RESULTS: Overall, gains in bone mass were maintained in patients who received 3 years of active treatment. In patients originally randomly assigned to receive placebo, initial losses in bone mass during the first 2 years were reversed and replaced with marked increases after the switch to active treatment. All patients who had initially received placebo showed significant, dose-related, clinically relevant increases (2.77% +/- 0.99%; P =.0048; to 7.36% +/- 0.74%; P =.0001) in lumbar spine bone mineral density relative to the end of the second year of the original study; smaller final-year increases were noted among the patients who had been actively treated for all 3 years. Similar trends were reported for femoral, trochanter, and total hip bone mineral densities. Mean total body bone mineral density either increased or remained unchanged in all dosage groups. These results were accompanied by parallel changes in levels of serum and urinary markers of bone turnover, with all markers approaching or returning to premenopausal levels by month 36. The high tolerability of this formulation during years 1 and 2 was maintained during year 3; 5.5% of patients withdrew from treatment because of adverse events in the final year. CONCLUSION: The Menorest formulation of transdermal 17beta-estradiol maintained bone mineral density gains in postmenopausal women and was well tolerated through a 3-year treatment period. It was also effective in reversing the initial bone loss associated with late commencement of therapy.

Absorptiometry, Photon↗
PubMed1998

Bilateral simultaneous hearing preservation mastoidectomy in otogenic meningitis.

Bilateral simultaneous hearing conservation mastoidectomy has not been previously documented. We present our experience with this procedure. Three patients with pyogenic meningitis secondary to bilateral unsafe ears had hearing preservation surgeries of both ears in a single sitting. Although ear surgery carries risk of inner ear damage, in our series there was no deterioration of inner ear function in the 6 ears operated on. The air conduction threshold improved in 3 (50%) of the ears. When meningitis results from bilateral otogenic foci as in our series, simultaneous mastoidectomy in both ears may be the preferred method of treatment to eradicate the source of infection.

Adult↗
PubMed1983

Noise-induced hearing loss in shipyard workers with unilateral conductive hearing loss.

In a study of 6500 workers in the shipbuilding industry, 8 subjects were found to have unilateral conductive hearing impairment established before the noise exposure period and without recurrent attacks of acute or chronic infection or clinical diagnosis of otosclerosis. All subjects demonstrated a more pronounced sensorineural hearing loss at 4.0 kHz in the ear with normal middle ear function. The results show the value of even a small permanent conductive hearing loss for protection against noise-induced hearing loss. The observations are discussed in relation to the role of individual variations in sound transmission, the value of the acoustic reflex in noise-induced hearing loss and the efficiency of continuous use of hearing protectors.

Auditory Threshold↗
PubMed2006

Randomized trial comparing low-dose hormone replacement therapy and HRT plus 1alpha-OH-vitamin D3 (alfacalcidol) for treatment of postmenopausal bone loss.

We conducted a prospective, randomized, multicenter, open-label 2-year trial with 76 postmenopausal women aged > or =60 years with low (T-score less than -1) lumbar bone mineral density (BMD). The hormone replacement therapy (HRT) group received a low dose of conjugated estrogen (CEE) at a dose of 0.31 mg/day +/- medroxyprogesterone acetate (MPA) 2.5 mg/day. Group HRT/D received the same dose of HRT together with alfacalcidol in a daily dose of 1.0 microg/day. Changes in lumbar BMD measured by dual energy X-ray absorptiometry (DXA) were followed every 6 months for 2 years. The lumbar BMD of group HRT increased 3.37% [95% confidence interval (CI) 1.6%-5.2%], 4.00% (95%CI 1.6%-6.4%), and 2.32% (95%CI -0.7% to 5.3%) at 12, 18, and 24 months, respectively, when the baseline value was taken as 0%. Lumbar BMD of group HRT/D showed a significant increase beyond 6 months. The percent increases for this group at 6, 12, 18, and 24 months were 6.18 (95%CI 1.3%-6.6%), 6.18% (95%CI 3.9%-8.5%), 7.17% (95%CI 4.3%-10.0%), and 8.75% (95%CI 6.0%-11.5%), respectively. In addition, there was a significant difference in the changes of the lumbar BMD between the two groups at 24 months, suggesting that the combination of HRT and alfacalcidol is more effective than HRT alone in terms of the BMD effect. This study is the first prospective trial demonstrating an additive effect of alfacalcidol on lumbar BMD in postmenopausal women receiving low-dose HRT. It suggests that the combination therapy can be considered to be a promising mode of treatment for bone loss after menopause.

Absorptiometry, Photon↗
PubMedDate not supplied

Comparison of small fenestra and total stapedectomy.

A biostatistical study of the results of 280 consecutive operations for clinical otospongiosis are analyzed over a seven-year period. One hundred forty-one (141) operations were done utilizing the "total stapedectomy" technique, and 139 were done utilizing the "small fenestra" technique. The auditory acuity of the two groups is compared with reference to conductive and sensorineural performance. All the surgery was performed by the authors, the data was collected by a third party and analyzed by a statistician. All audiograms were performed by the same audiologist under the same conditions. The data indicates that the preferred operation for this clinical disease is the small fenestra technique.

Bone Conduction↗
PubMed1989

Effect of human recombinant IL-2 on murine macrophage precursors. Involvement of a receptor distinct from the p55 (Tac) protein.

Homogeneous populations of bone marrow-derived murine macrophage precursors are able to respond to human rIL-2. A prolonged exposure to the lymphokine results in proliferation and in the final differentiation of macrophage precursors to mature macrophages, as shown by follow-up of the antigenic profile by means of cytofluorograph analysis. The frequency of the IL-2-responding cells was 1/48 as determined by limiting dilution analysis, and no cell death was evidenced in soft agar cultures. An analysis of the IL-2-binding sites conducted on bone marrow-derived macrophage precursors revealed the presence of 4000 binding sites with intermediate affinity (Kd approximately 3 x 10(-9)). Bone marrow-derived macrophage precursors did not react, even after prolonged culture in IL-2-conditioned media, with mAb recognizing the binding site (AMT-13, 3C7) or a binding site-associate molecule (7D4) of a Mr 50,000 to 60,000 component of the IL-2R expressed by the IL-2-dependent T cell line CTLL-2. Cross-linking studies showed the presence of a single binding protein, with an apparent Mr of 70,000. Macrophage precursors also proved able to internalize human rIL-2 within the first 20 min of incubation at 37 degrees C. The implications of these findings are discussed.

Animals↗
PubMed1993

Declining lymphocyte counts following cytomegalovirus (CMV) infection are associated with fatal CMV disease in bone marrow transplant patients.

A previous pilot study conducted on 12 bone marrow transplant recipients suggested that detection of cytomegalovirus (CMV) in lymphocytes was associated with a drop in lymphocyte counts and death due to CMV disease. To test the association between decreasing lymphocytes and CMV-related death, we undertook a retrospective study of 332 CMV-infected patients transplanted between 1987 and 1990. The patients were divided into three groups: I = 170 patients who survived their infection and were alive at the time of the study; II = 103 patients who died of causes other than CMV infection; and III = 59 patients who died of CMV disease. Lymphocyte counts were analyzed during a 24-day period, starting 10 days before the day of first positive CMV culture (day 0). Lymphocyte counts were significantly lower in Group III from day 0 through day +14 (p < .001 vs. group I; and p = .002 vs. group II). Multivariate statistical analysis was used to adjust for other differences between the groups that might influence lymphocyte numbers. Average lymphocyte counts in patients who died of CMV disease decreased by an average of 35% after day 0. The differences in lymphocyte counts remained independent of the effects of acute graft-vs.-host disease (GVHD), time since transplant, transplant type, and high-dose steroid treatment. In summary, these data suggest that in some patients a drop in lymphocyte counts is a consequence of CMV infection associated with fatal CMV disease. Whether this can be attributed to direct infection of lymphocytes, a defective immune response, or some other mechanism remains to be determined.

Adult↗
PubMed2006

Perinatal exposure to PCB 153, but not PCB 126, alters bone tissue composition in female goat offspring.

The aim of this study was to investigate if environmentally relevant doses of the putative estrogenic non dioxin-like PCB 153 and the dioxin-like PCB 126 caused changes in bone tissue in female goat offspring following perinatal exposure. Goat dams were orally dosed with PCB 153 in corn oil (98 microg/kg body wt/day) or PCB 126 (49 ng/kg body wt/day) from day 60 of gestation until delivery. The offspring were exposed to PCB in utero and through mother's milk. The suckling period lasted for 6 weeks. Offspring metacarpal bones were analysed using peripheral quantitative computed tomography (pQCT) after euthanisation at 9 months of age. The diaphyseal bone was analysed at a distance of 18% and 50% of the total bone length, and the metaphyseal bone at a distance of 9%. Also, biomechanical three-point bending of the bones was conducted, with the load being applied to the mid-diaphyseal pQCT measure point (50%). PCB 153 exposure significantly decreased the total cross-sectional area (125 mm(2)+/-4) versus non-exposed (142 mm(2)+/-5), decreased the marrow cavity (38 mm(2)+/-4) versus non-exposed (50 mm(2)+/-3) and decreased the moment of resistance (318 mm(3)+/-10) versus non-exposed (371 mm(3)+/-20) at the diaphyseal 18% measure point. At the metaphyseal measure point, the trabecular bone mineral density (121 mg/cm(3)+/-5) was increased versus non-exposed (111 mg/cm(3)+/-3). PCB 126 exposure did not produce any observable changes in bone tissue. The biomechanical testing of the bones did not show any significant changes in bone strength after PCB 153 or PCB 126 exposure. In conclusion, perinatal exposure to PCB 153, but not PCB 126, resulted in altered bone composition in female goat offspring.

Administration, Oral↗
PubMed2000

Revision stapedectomy.

OBJECTIVE: To evaluate results of revision stapedectomy with and without use of the laser and determine factors predictive of hearing outcome. STUDY DESIGN AND SETTING: Retrospective review of 356 revision stapedectomy operations performed at the House Ear Clinic, a tertiary neurotologic private practice, between 1983 and 1995. RESULTS: A postoperative gap of < or =10 dB was obtained in 60% of cases. Results were similar with and without the use of a laser. Sensorineural hearing loss of >10 dB occurred in 7.7%, with 3 (1.4%) ears with profound hearing loss. A poorer outcome was related to incus necrosis, multiple revisions, and indications for surgery other than conductive hearing loss. CONCLUSION: Revision stapedectomy can provide good gap closure in 60% of cases, with small risk of sensorineural hearing loss. SIGNIFICANCE: Although not as satisfactory as primary stapedectomy, revision stapedectomy can be offered to patients with reasonable expectations for good gap closure.

Adolescent↗