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PubMed1985

[Bone biopsy in hematology].

The importance of bone marrow biopsy in haematology lies in the fact that it puts relatively little stress on the patient and can reliably diagnose numerous blood diseases involving the bone marrow. It also provides information on the state of the bone marrow after treatment, and is essential for restaging in cases of lympho-proliferative diseases. A total of 116 personally conducted bone marrow biopsies proved to be a basic test for certain pathologies (medullary hypoplasia, myelofibrosis, N. H. lymphomas); while for others (leukaemia, plasmocytoma, polycythaemia), it was revealed to be a valuable back-up to clinical examination and other diagnostic procedures.

Biopsy↗
PubMed2001

[Tympanoplasty for patients with destruction of the stapes].

Mode of tympanoplasty allowing reconstruction of the drum and erosioned malleus handle is described. For this purpose an autoossicle fragment of the lengthened shape was inserted into the blind channel created in fascia transplant which "dressed" on the handle's remnant for the osseous fragment and remnants of the handle to appear in one fascia channel. This method was applied in 11 patients with subtotal drum perforation and erosion of the hammer's handle. In 9 of them 0.5-2 years later the defect of the drum fully disappeared. In 7 patients the handle resumed normal length while the drum became conic. The average pure air conduction threshold in frequencies 0.5-2 kHz has become 25.5 +/- 3.5 dB (before the operation 38.2 +/- 2.3 dB; p > 0.01), the average bone conduction threshold 14.3 +/- 2.6 dB (before operation 13.9 +/- 2.4 dB; p < 0.05).

Ear Ossicles↗
PubMed1983

Direct bone anchorage of external hearing aids.

Some patients with hearing disorders cannot wear a conventional hearing aid but have to use bone conduction in which the aid has to be attached with steel springs over the head. A new method of reconstruction involving the insertion of bone-anchored screws has been tested in a clinical survey of 14 patients. A titanium implant was anchored in the temporal bone and, in a later session, connected to a skin penetrating abutment. An external hearing aid was snapped on to the abutment. The patients have now been followed up for 53 months. There have been no problems with the bone anchorage or with infections around the skin penetration site. The hearing of the patients has improved. The cosmetic result is reported to be favourable.

Adolescent↗
PubMed1995

[Bone anchored hearing aids (Audiant): long-term use].

This report concerns the long term utilisation of a bone anchored hearing aid system, Audiant, in a large district general hospital in England serving a population of 500,000. Earlier experience with some of these patients has been previously reported (6). All patients included in this series had been provided with conventional hearing aids but for various reasons, indicated in the text, had found them unsatisfactory. Efforts to overcome some of these difficulties led to the utilisation of the osteointegrated hearing aid. Patients regard it to have significant advantages over their previous hearing aids. Some who had previously used conventional bone conduction hearing aids, are now able to use an ear level processor. Of the eleven patients implanted, eight continue to use their bone-anchored hearing aids, two having had their implant for 6 years, three for 5 years and three for 2 years.

Audiometry↗
PubMed2003

Radiotherapy-induced ear toxicity.

Despite their particular functional consequences, radiotherapy-induced ear injuries remain under-evaluated and under-reported. These reactions may have acute or late character, may affect all structures of the hearing organ, and result in conductive, sensorineural or mixed hearing loss. Up to 40% of patients have acute middle ear side effects during radical irradiation including acoustic structures and about one-third of patients develop late sensorineural hearing loss (SNHL). Total radiotherapy dose and tumour site seem to be among the most important factors associated with the risk of hearing impairment. Thus, reduction in radiation dose to the auditory structures should be attempted whenever possible. New radiotherapy techniques (3-dimensional conformal irradiation, intensity modulated radiotherapy, proton therapy) allow better dose distribution with lower dose to the non-target organs. Treatment of acute and late external otitis is mainly conservative and includes the anti-inflammatory agents (applied topically and systematically). Post-radiation chronic otitis media and the eustachian tube pathology may be managed with tympanic membrane incision with insertion of a tympanostomy tube (grommet), although the benefit of such approach is controversial and some authors advocate a more conservative approach. In these patients the functional deficit can be alleviated by application of bone conduction hearing aids such as, e.g., the bone anchored hearing aid (BAHA). There is no standard therapy for post-irradiation sudden or progressive SNHL yet corticosteroid therapy, rheologic medications, hyperbaric oxygen or carbogen therapy are usually employed (as for idiopathic SNHL), although controversial data on the efficacy of these treatment modalities have been published. In selected cases with bilateral profound hearing loss or total deafness, cochlear implants may prove effective. Further improvements in radiotherapy techniques and progress in otologic diagnostics and therapy may allow better prevention and management of radiation-related acoustic injury.

Audiometry↗
PubMed2007

Updated surgical experience with bone-anchored hearing aids in children.

BACKGROUND: We present the results of a retrospective review of children undergoing implantation with bone-anchored hearing aids (BAHAs) at the Great Ormond Street Hospital for Children. METHODS: The case notes of 71 children undergoing BAHA placement at the Great Ormond Street Hospital for Children between December 1990 and August 2002 were reviewed. Outcome measures included hearing thresholds, incidence of fixture loss, skin reaction and need for revision. Quality of life outcomes were also measured. RESULTS: Eighty-five ears had been implanted. Fifty-four per cent of children had experienced no complications, 42 per cent had required revision surgery and 26 per cent had experienced fixture loss at some point. Young age at implantation was associated with an adverse outcome. Trauma and failure of osseointegration had been the commonest reasons for failure. A skin reaction around the abutment had occurred at some point in 37 per cent of children but had persisted for longer than six months in only 9 per cent; this had been associated with fixture loss. The use of fixture site split skin grafts had reduced problems with skin hypertrophy and hair overgrowth. Hearing thresholds when using BAHAs had been comparable to those when using bone conduction hearing aids. However, BAHAs had significant additional benefits in terms of sound quality, ease of use and overall quality of life. CONCLUSION: Bone-anchored hearing aids provide significant benefits over other types of hearing aid, both audiologically and in terms of quality of life. Careful selection of candidates and meticulous follow up are required in order to minimize complications.

Adolescent↗
PubMed2003

Percutaneous bone-anchored hearing aid.

Patients born with severe dysmorphology involving the ears usually have hearing derangements as well as other areas of the craniofacial skeleton affected. To correct the functional problem, the usual and customary treatment is augmentation of the hearing with a bone conducting hearing device. The patients have to wear these devices with an external band. The new advances in osseointegrated implant allowed us today to utilize the same technology in the patient with the application of a bone anchored hearing device. The advantages are related to the obviation of the need to use a hearing band across the head, that most children object to, and the new device is much smaller than the large and cumbersome banded device. There is also an added advantage in the improvement of the hearing as the units are anchored internally in the bone. The device utilizes digital technology and can be calibrated easily. The patient can apply the device in the morning by a simple application click. The disadvantage to the patient is that the area requires consistent maintenance and care, however, this operation can be done very easily. A sleeper osseointegrated unit is kept as a spare that can be utilized if any osseo-integrated functional problem appears. The functional changes in the hearing and the audiological improvements are well documented.

Child↗
PubMed1996

Basic fibroblast growth factor enhances bone-graft incorporation: dose and time dependence in rats.

In a previous study, we found that basic fibroblast growth factor could stimulate bone-graft incorporation. In the present study, the effects of different doses and implantation times were further studied, using the bone conduction chamber, in rats. Inside the chamber, the graft is isolated from the surrounding tissues except at one end, where small openings embedded in host bone allow ingrowth of tissue. The distance that new tissues had reached from the openings into the graft was measured on histological slides. Bone grafts were obtained from the proximal tibiae of donor rats, frozen at -70 degrees C, and lipid-extracted. Before implantation, they were soaked overnight in a hyaluronate gel with or without basic fibroblast growth factor and then were fitted into the chambers, which were implanted in the proximal tibiae of recipient rats. In a dose-response experiment, grafts containing 0.3, 8, 40, 200, or 1,000 ng of basic fibroblast growth factor were compared with grafts treated with carrier gel only, after an implantation time of 6 weeks. Fibrous tissue always penetrated the grafts further than the ingrown bone; the distance that it reached from the ingrowth openings (total ingrowth distance) was increased by all of the doses except 0.3 ng per implant. The distance of bone ingrowth was increased by 8, 40, and 200 ng. The increased total ingrowth with 1,000 ng was due to an increased amount of fibrous tissue ahead of the bone, whereas with the lower doses the increase was due to more bone. Thus, the dose had an effect on the type of ingrown tissue found in the graft. In a time-effect study, grafts treated with 40 ng of basic fibroblast growth factor had a higher uptake of [99mTc]MDP at 2 and 4 weeks and an increased bone ingrowth distance at 10 weeks. The radioactivity from [125I]basic fibroblast growth factor declined with a half-life of 17 hours. The results suggest that basic fibroblast growth factor may be beneficial for the incorporation of contained bone grafts; studies using more clinically relevant models are required.

Animals↗
PubMed2006

Auditory pathway in rheumatoid arthritis. A comparative study and surgical perspectives.

CONCLUSION: Rheumatoid arthritis (RA) patients present with both conductive and sensorineural deafness. OBJECTIVE: To evaluate the prevalence and features of hearing impairment in patients with RA. MATERIAL AND METHODS: A total of 28 RA patients underwent a rheumatological evaluation, including determination of rheumatoid factor, protein 2-glycoprotein I level and the Lee index. An audiological assessment consisting of pure-tone audiometry (PTA) and determination of auditory brainstem responses (ABRs) and transient evoked otoacoustic emissions (TEOAEs) was performed. The results were compared with those of 28 age- and sex-matched healthy subjects. Four selected RA patients underwent stapedectomy; PTA and TEOAEs were evaluated 6 months postoperatively. RESULTS: Increased air conduction thresholds at 250, 500 and 1000 Hz were found in RA subjects in comparison to controls (p<0.001). RA patients showed higher air-bone gaps in PTA (p<0.05) and an increased Wave I latency in ABRs (p=0.03). Decreased reproducibility (p<0.001) and amplitude (p<0.001) of TEOAEs were found in RA subjects in comparison to controls. A significant correlation between disease duration and echo amplitude was noticed (r=0.389). After stapedectomy, a reduction in the air-bone conduction gap (11 vs 2 dB HL) was noticed; no significant difference in TEOAEs was found.

Adult↗
PubMed1996

Sensory nerve ingrowth during bone graft incorporation in the rat.

We studied nerve ingrowth into a cancellous bone graft in a bone conduction chamber model in the rat. Before implantation of the chamber bilaterally in the proximal tibiae of 8 Sprague-Dawley rats, a defatted cancellous bone graft from separate donor rats was fitted snugly into each chamber. After 6 weeks, the animals were perfused with Zamboni's fixative and the chambers were harvested. Immunohistochemical detection of nerve fibers was performed in cryostat sections, using antisera to protein gene product 9.5 (PGP 9.5), neural growth-associated protein GAP-43/B-50, calcitonin gene-related peptide (CGRP), substance P and C- flanking peptide of neuropeptide Y (CPON). Nerve fibers were found in 10 out of 16 samples in the newly formed bone, and also in the fibrous tissue which had penetrated deeper into the graft. The nerve fibers were mainly of sensory origin, as they showed immunoreactivity for CGRP and GAP-43/B-50. We speculate that the nerve fibers may act as transmitters of nociceptive impulses from the graft, and as transport pathways for neuropeptides that are actively involved in angiogenesis and in the recruitment and activity of osteogenic cell populations from the graft recipient.

Animals↗
PubMed2003

Audiologic monitoring for potential ototoxicity in a phase I clinical trial of a new glycopeptide antibiotic.

This study describes audiologic methodology and results for evaluating potential ototoxicity in a phase I clinical trial of a new glycopeptide. This study was conducted under good clinical practices, which are regulated by the US Food and Drug Administration (FDA) (21 Code of Federal Regulations), and input from the FDA was sought prior to study implementation. Healthy, normal volunteers underwent extensive medical and audiologic assessments as part of this phase I dose- escalation study of dalbavancin, a new glycopeptide, to assess potential side effects. Audiologic monitoring included air-conduction thresholds in the conventional (0.25-8 kHz) and high-frequency (10-16 kHz) ranges. At baseline, subjects were also tested using word recognition, bone conduction testing if indicated, and tympanometry. Full testing was to be repeated if any subject met the American Speech-Language-Hearing Association (ASHA) 1994 criteria for ototoxic change. However, no subjects demonstrated ototoxic change after receiving dalbavancin, nor were any false-positive results obtained.

Acoustic Impedance Tests↗
PubMed1979

Middle fossa vestibular nerve section. A histopathological report.

A patient with Meniere's disease underwent a middle fossa superior and inferior vestibular nerve section with excision of Scarpa's ganglia. Studies of this patient's temporal bone, conducted two and one-half years post-operatively, showed normal cochlear and facial nerves. The internal auditory canal showed fibrosis and new periosteal bone formation. There was complete denervation of the vestibular labyrinth except for the posterior semicircular canal crista. Fibrous and osteoid tissue filled the superior and lateral semicircular canals. In this case, these severe degenerative changes, presumably associated with biochemical changes in the vestibular labyrinth, altered the natural course of Meniere's disease. Vertigo was completely relieved, tinnitus improved, and hearing thresholds stabilized during the course of post-operative follow-up.

Ear↗
PubMed1986

[Hearing disorders in Paget's disease].

The audiometric data of 41 patients with Paget's disease of the bone show that hearing loss exceeds the age-related presbycusis in patients with deformities of the temporal bone as demonstrated by X-ray (27%). The usual type of hearing loss is a sensorineural one. 80% of these patients showed hair cell damage, 32% of them a retrocochlear lesion, depending on the degree of deformity of the temporal bone. Conductive hearing loss of the otosclerosis type was found in only 20%. The Paget-related hearing loss can be regarded as a consequence of the deformation occurring both at the bone surrounding the cochlea and at the internal auditory canal.

Acoustic Impedance Tests↗
PubMed2006

Dual hydroxyapatite composite with porous and solid parts: experimental study using canine lumbar interbody fusion model.

Hydroxyapatite (HA) has been evaluated for use in a variety of applications in bone reconstruction surgery because of its high affinity with host bone and biocompatibility. However, because of the difficulty in combining porosity (for bone ingrowth) and strength in HA, it is generally considered inappropriate to use HA for high-load applications such as spinal interbody fusion. In the present study, we constructed a HA implant for spinal interbody fusion, composed of a dual HA composite (DHC) that combines two HA materials with different porosities: HA with 75% porosity, for bone ingrowth; and HA with 0% porosity, for load bearing. We used a canine lumbar interbody fusion model to evaluate bone conduction of the implant and its efficacy for bony fusion. Six months after the operation, DHC exhibited almost the same efficacy for bony fusion as iliac bone grafts. Moreover, pores of the porous part of the DHC were completely filled with newly formed bone and bone marrow cells. The present findings indicate that DHC is suitable for use as an implant material for spinal interbody fusion as a substitute for iliac bone grafts, which could eliminate the disadvantages associated with autograft harvesting.

Animals↗
PubMed2005

The complete process of bioresorption and bone replacement using devices made of forged composites of raw hydroxyapatite particles/poly l-lactide (F-u-HA/PLLA).

Here we document the complete process of bioresorption and bone replacement of rods made of forged composites of unsintered hydroxyapatite particles/poly l-lactide (F-u-HA/PLLA) implanted in the femoral medullary cavities of rabbits. Bioresorption, osteoconductive bioactivity and bone replacement were compared in three implantation sites. In the first site, the end of the rod was located near the endosteum in the proximal medullary cavity. In the second, the rod was located at the centre of the bone marrow space without contacting the endosteum. In the third, the rod was in direct contact with cancellous bone within the distal femoral condyle. Micro-computerised tomography, scanning electron microscopy and photomicrographs of stained sections were used to document the complete process of bioresorption and bone replacement. At the first implantation site, the rod was completely resorbed and unbound u-HA particles were detected in and around the endosteum 5-6 years after implantation. At the second site, the rod showed significant shrinkage 4-5 years after implantation due to the release of almost all the PLLA, although a contracted cylindrical structure containing a few u-HA persisted even after approximately 6 years. At the third site, u-HA particles were almost completely replaced with bone after 5-6 years. Conversely, PLLA-only rods showed little bone conduction, and small amounts of degraded PLLA debris and intervening some tissue persisted even after long periods. Namely, the u-HA/PLLA composites were replaced with bone in the distal femoral condyle, where they were in direct contact with the bone and new bone formation was anatomically necessary. By contrast, composite rods were resorbed without replacement in the proximal medullary cavity, in which new bone growth was not required. We therefore conclude that the F-u-HA30/40 composites containing 30 wt%/40 wt% u-HA particles are clinically effective for use in high-strength bioactive, bioresorbable bone-fixation devices with the capacity for total bone replacement.

Absorbable Implants↗
PubMed2006

Inner ear anomalies in cochlear implantees: importance of radiologic measurements in the classification.

OBJECTIVE: To classify the inner ear anomalies of cochlear implantees with profound sensorineural hearing loss. STUDY DESIGN: Retrospective case review. SETTING: Tertiary referral center. PATIENTS: For the normative data of the inner ear structures, the temporal bone computed tomography of 60 patients (120 ears) with normal bone-conduction threshold (< 15 dB) were used, and the data were applied to 570 ears of 285 cochlear implantees. INTERVENTIONS: Predesignated inner ear structures were measured in temporal bone computed tomography images from the normal and cochlear implantation groups using a computer-based caliper that formed part of a picture archiving and communication system. MAIN OUTCOME MEASURES: The inner ear anomalies were defined when the structures presented visually obvious malformations or the measurements deviated 2 standard deviations from the means in the normative data. RESULTS: The application of normative data to 570 profound SNHL ears resulted in the identification of 293 individual anomalies in 127 anomalous ears. An enlarged vestibular aqueduct was the most common individual anomaly (49 cases), followed by vestibular enlargement (38 cases) and other semicircular canal dysplasia (37 cases). When the individual anomalies were reaccounted according to the more prominent anomaly where multiple anomalies were present in each ear, incomplete partition type II was the most common (34 ears), followed by cochlear hypoplasia (22 ears) and incomplete partition type I (20 ears). CONCLUSION: We suggested a measurement technique for the inner ear structures using computed tomography and derived normative measurements helpful for diagnosing inner ear anomalies. Using these normative data, we classified the inner ear anomalies of profound SNHL ears in cochlear implantees.

Adolescent↗
PubMed2003

Clinical-embryological and radiological correlations of oculo-auriculo-vertebral spectrum using 3D-CT.

OBJECTIVES: The purpose of this paper is to present a variety of imaging findings of oculo-auriculo-vertebral spectrum (Goldenhar syndrome) using three-dimensional reconstructed images from computed tomography (3D-CT), associating clinical and embryological patterns of the syndrome. METHODS: The study population consisted of 10 patients with oculo-auriculo-vertebral spectrum with clinically identified hemifacial microsomia. The patients were examined using spiral CT, and abnormal imaging features were grouped under facial, ear and temporal bone, vertebral, and skull base anomalies. The original CT data were transferred to a networked computer workstation with a computer graphics system to generate 3D-CT volume rendered images of the skull and vertebra. Two observers analysed the bone and muscular setting protocols to assess the relationship between bone and muscular structures. RESULTS: Asymmetric underdevelopment was a characteristic pattern of this syndrome resulting from hypoplasia of the mandibular ramus and condyle, the zygomatic, sphenoid and auricular conduct bones, and the temporal and masseter muscles. The syndrome was associated with local atrophy seen on 3D-CT images using specific bone and muscles protocols in all cases. CONCLUSIONS: Understanding the aetiology, embryology and wide imaging spectrum of this syndrome is essential to make a correct diagnosis, for treatment planning, and for evaluation when associated with a 3D-CT computer graphics system.

Adolescent↗
PubMed1977

Test of environmental exposure to arsenic and hearing changes in exposed children.

Arsenic determination was carried out on hair, urine, and blood samples taken from groups of 10-year-old boys, each numbering 20 to 25 individuals, residing in a region polluted by arsenic. In all the examined materials considerably elevated concentrations of arsenic were found. The relation of the observed levels of arsenic to the distance of the place of residence up to a distance of more than 30 km from the source of the emissions was studied. On the basis of the results obtained, the most advantageous material for estimation of nonoccupational exposure to arsenic seems to be hair, in spite of some problems with the decontamination procedure involved. Considerable variability among individual arsenic values in the hair makes group examination a necessity. Hearing changes were analyzed in a group of 56 10-year old children residing near a power plant burning local coal of high arsenic content. The results of both audiometric and clinical examination were compared with those of control group numbering 51 children of the same age living outside the polluted area. The highly standardized audiometric and clinical examination were completed with a questionnaire analysis concerning the personal medical histories of the children. The obtained data were elaborated statistically by means of the chi(2)- test. In the case of air conduction, important hearing losses were found at frequencies of 125, 250 and 8000 Hz, especially at the lowest frequency range. Significant degrees of hearing loss were found in bone conduction as well as in the corresponding ranges of frequencies. The high statistical significance of the hearing impairments found points to very low probability of their being only an "accidental" finding. The possibility of toxic damage to the ear cannot yet be excluded.

Arsenic↗