PubMed Health⌕ Search

Biomedical subjects

E Bachor

Publications and source records attributed to E Bachor.

At least 19 recordsLinked to original sources

[Measurement of noise protection in functional magnetic resonance imaging].

BACKGROUND: Functional magnetic resonance imaging (fMRI) can detect changes in oxygen saturation of the brain. Fast changing high gradient fields are necessary which produce high levels of noise. In studies of the auditory cortex, auditory stimuli have to be perceived and discriminated against the noise level of the activated tomograph. MATERIAL AND METHODS: The generated frequency bands and their intensities during fMRI with a Siemens Magnetom Vision, 1.5 T, EPI sequence were measured in the outer ear canal of a dummy head. Noise attenuation was evaluated with four different noise muffs (simple/inexpensive products, quality product, specialized fMRI muffs). RESULTS: Without protection, peak noise levels reached up to 111 dB(A) near 1000 Hz in the dummy ear canal. Major noise attenuation was only found at higher frequencies (4000 Hz by about 25 dB; 8000 Hz by about 35 dB) with the quality product and the specialized fMRI muffs. CONCLUSION: Only quality noise products can sufficiently protect patients from high sound pressure levels of tomograph noise. If in the future higher gradient fields are applied at faster slew rates, acoustic stimuli can safely be applied only in combination with increased hearing protection systems in order to minimize the risk of noise trauma.

Ear Protective Devices↗

[Reimbursement of patients with high costs in a department of otorhinolaryngology of maximum care and refinancing by the German DRG system].

BACKGROUND: With the introduction of a diagnosis related groups (DRG)-system in Germany, the medical analysis of the total costs of caring for a given patient is of significance. The medical identification of cost intensive patients becomes of increasing importance for the financial perspective of a department, because the averaged lump sum system might not break even these treatments. PATIENTS AND METHODS: In the Department of Otorhinolaryngology, University Ulm, a tertiary referral center, the 56 most expensive patients from 3131 inpatients which were treated in 2002 were retrospectively identified and expenses for diagnostic tests, therapy and post-operative complications were analyzed. All patients' related costs, including all costs for personnel, were assigned to a DRG (Version 1.0 G-DRG and G-DRG 2004). RESULTS: The most expensive treatments included extensive tumor surgeries, surgery of the trachea, emergency procedures and reconstructive surgery. Costs increased with complications, prolonged stay in the intensive care unit and simultaneous internal diseases. The cost at our institution for an pharynocutaneous fistula added 3000 Euro. CONCLUSION: The assignment of treatment costs to a DRG is complex. Based on our data extensive surgeries for head and neck malignancies showed a homogeneous cost distribution in the DRG group of G-DRG 2004 which was however inadequately reimbursed. Detailed prospective analyses from multiple centers to identify expensive treatments in the field of otorhinolaryngology are necessary to incorporate modifications into the German DRG-system.

Adult↗

Coincidence of normal tension glaucoma, progressive sensorineural hearing loss, and elevated antiphosphatidylserine antibodies.

BACKGROUND: Recently, in patients with normal tension glaucoma (NTG) elevated levels of antiphosphatidylserine antibodies (APSA), a subgroup of antiphospholipid antibodies (APLA) were found. Progressive sensorineural hearing loss (PSHL) is associated with autoimmune diseases and also the presence of APLA. METHODS: To investigate a possible association between NTG and PSHL, 34 patients (age range 31-81 years) with NTG were evaluated for evidence of audiovestibular disorders. Besides ophthalmological standard examinations (slit lamp, IOP, funduscopy, perimetry) scanning laser tomography and polarimetry were performed. From all patients' audiograms, stapedial thresholds and otoacoustic emissions were obtained. The serological testing of patients and controls (40 healthy blood donors older than 50 years) concerned IgG and IgM levels of antibodies against phosphatidylserine (APSA) and beta2 glycoprotein. RESULTS: 23 of 34 NTG patients had hearing loss (PSHL n = 11; presbyacusis n = 12). The NTG patients had significantly higher APSA levels than controls. Elevated APSA concentrations were significantly more frequent in patients with NTG and hearing loss compared with NTG patients with normacusis. CONCLUSIONS: These findings show that NTG and hearing loss have a high coincidence. The elevated APSA levels may indicate an association with similar systemic autoimmune processes.

Adult↗

[Retraction of the endolymphatic membranes in temporal bones of the Wittmaack and Tufts collections].

BACKGROUND: In histologic studies, the volumetric status of the intralabyrinthine fluids is judged by the position of the endolymphatic membranes. Bulging of the membranes, commonly known as endolymphatic hydrops, is assumed to be caused by excess of endolymph. The opposite situation, retraction of the membranes is, however, only incidentally described and relatively little attention has been paid to its significance. Almost one hundred years ago Wittmaack described retraction of the endolymphatic membranes, which has since been considered to be preparation artifact--a concept that essentially remains unchallenged. To test the validity of this long premise, we examined two sets of temporal bones from different centers. MATERIAL AND METHODS: We studied the following collections: 1. The Wittmaack collection in Hamburg, Germany. The original material of 67 temporal bones (patient ages 0-92 years, average age 35.2 years) on which Wittmaack based his opinions. 2. For comparison and to exclude age related phenomena, 125 temporal bones from 73 children between the ages newborn to ten years (average age 13.4 months, median 1.5 months) from the temporal bone collection of the Department of Otolaryngology Tufts University School of Medicine. All specimens were studied by light microscopy. Retraction was defined as depression of Reissner's membrane toward the stria vascularis and the Organ of Corti in more than one cochlear turn and was graded into mild, moderate and severe. Additionally the saccule, utricle and semicircular ducts were examined for collapse. RESULTS: The reevaluation of the 67 temporal bones described by Wittmaack, including those of 7 children below the age of 10 years, showed retraction of Reissner's membrane in 81% compared to 33% of the temporal bones from the Tufts collection. In contrast to the high incidence of retraction in the cochlear duct, fewer saccules (12%) and utricles (4%) were collapsed in the Tufts collection. In the Wittmaack collection no significant differences between the underlying diseases were found, however in the Tufts collection the group of children who suffered from extracochlear infections and malignancies had a higher frequency of retraction. CONCLUSION: Mild retraction might be to some extent physiologic or even artifactual. Severe retraction, however, is a definitive finding that is a part of a local or regional otopathologic process. Of material, it is quite possible that Wittmaack's original observations of what he called "hypotonic collapse" was of viral origin (viruses were not known during Wittmaack's time), ototoxicity or even of genetic origin.

Adolescent↗

[Cochlear implantation: relationship between speech development and insertion depth in children].

BACKGROUND: The goal in pediatric cochlear implantation is improved hearing leading to better speech development, which may allow their integration into mainstream schools. Whether the intracochlear position of the electrode array has an influence on speech development or not is controversially discussed. PATIENTS: Between 1996 and 1998 29 children ranging from 1.5 to 11.8 years (median 4 years) were provided with a Nucleus 22M or 24M cochlear implant system. Speech and language skills were assessed by a closed-set test (Mainzer test) and by the Schmid-Giovannini score for hearing development pre-implantation and at 6, 12, 18 and 24 months post-implantation. The position of the electrode array was determined by the surgical record and by a postoperative transorbital x-ray. Since the promontory has a thickness of one to two electrode bands, we defined deep insertion as more than 24 bands intracochlear. RESULTS: The patients were divided into 2 groups according to the insertion depth: Group 1 (n = 8) 24 bands (22 electrodes and 2 stiffening rings correspond to < or = 18 mm) or less and group 2 (n = 21) more than 24 bands intracochlear correspond to > 18 mm). The mean closed-set test scores 12 months post-implantation were 51.4% and 68.5% for group 1 and group 2, respectively. Schmid-Giovannini test scores were 8.7 for group 1 and 10.1 for group 2. There was no significant statistical difference in the closed-set and Schmid-Giovannini test scores. We observed incomplete insertion (i.e. less than 22 active bands are intracochlear) because of electrode extrusion in only one child. CONCLUSION: Speech development in children does not improve with deeper insertion of the cochlear implant electrode array.

Age Factors↗

Vascular variations of the inner ear.

Vascular anomalies of the inner ear have been documented in only a few isolated case reports. The goal of our study was to describe, qualify and quantify vascular variations of the inner ear in 122 temporal bones from 64 pediatric subjects aged between 0 and 10 years. The average age was 11.6 months. Horizontal sections of the temporal bone, examined by light microscopy, revealed vessels coursing freely through the perilymphatic space of the cochlea, especially in the apical turn. Other findings included abnormally wide vessels in the stria vascularis as well as a vascular malformation of the internal auditory canal. Our study demonstrated more atypical vessels in the cochlea than in the vestibular labyrinth. We found a statistically significant positive correlation between vascular variations of the inner ear and concomitant cardiac anomalies or endolymphatic hydrops. We also discuss the possible etiology and potential significance of these findings in terms of disturbances of the function of the inner ear.

Child↗

Neural hearing loss in a child with poliomyelitis: a histopathological study.

The temporal bones of a 26-month-old white female with a paralytic syndrome clinically and pathologically identical to poliomyelitis were examined. The aetiological agent was unknown although a non-poliomyelitis enterovirus infection seemed likely. There was a complete absence of the cochlear neurons and substantially reduced peripheral and central axons with loss of some inner hair cells but preservation of outer hair cells. Scarpa's ganglion, and the geniculate ganglion were partially atrophied. The saccule and utricle were mildly dilated and Reissner's membrane of the apical turn was bulging. In two previous audiological studies a 10--20 dB bilateral sensorineural hearing loss was found in poliomyelitis patients and a neuronal lesion was postulated which is now supported by our findings. This is a rare example of an almost pure neural hearing loss.

Child, Preschool↗

The pathology of the temporal bones of a child with acquired cytomegalovirus infection: studies by light microscopy, immunohistochemistry and polymerase-chain reaction.

STUDY DESIGN: The first case of an acquired cytomegalovirus (CMV) infection of the inner ear is reported in a 3-year-old girl in remission from acute lymphocytic leukemia. METHODS: Horizontal sections of the temporal bones were studied by light microscopy and immunohistological staining by avidin-biotin-complex-technique was performed on selected archival sections. Three sections were processed for detection of the virus genome by the polymerase chain reaction (PCR). RESULTS: By light microscopy the epithelium of the endolymphatic sac, the utricle and the semicircular canals showed deeply stained acidophilic inclusions and the stria vascularis had a loose structure especially in the intermediate layer. The changes were limited to the non-sensory parts of the labyrinth and no CMV type cells were observed in the organ of Corti. There was a loss of inner and outer hair cells and loss of cochlear ganglion cells caused by either the virus or treatment with gentamicin. Standard immunohistochemistry failed to demonstrate staining with CMV antibodies, but PCR, demonstrated CMV-DNA in one section. CONCLUSION: Molecular techniques may be able to detect acquired CMV infections in archival pediatric bones temporal bones. The histologic findings in the labyrinth were milder, however showed some similarity to children with congenital CMV labyrinthitis.

Autopsy↗

[Ambulatory rehabilitation after cochlear prosthesis implantation].

BACKGROUND AND OBJECTIVE: This study compares the results of the outpatient-based program of the Cochlear Implant Center Ruhr with inpatient-based rehabilitation, which is almost exclusively performed in Germany. PATIENTS/METHODS: The Department of Otorhinolaryngology at the University of Essen in Germany provided 52 patients with either 22- or 24-channel Nucleus cochlear implants from March 1996 to July 1999. Almost all patients (n = 49) were rehabilitated on an outpatient basis, which is the standard in many cochlear implant centers outside Germany. RESULTS: The longest follow-up period at the University of Essen Department of Otorhinolaryngology was 36 months. Minor complications occurred in 10% of the patients. After 24 months, the first three implanted patients were able to discriminate 100% of numbers and over 60% of syllables in the Freiburg speech discrimination test. The patients who developed an understanding of open speech were able to discriminate 31 words per minute with cochlear implant and without lipreading after 24 months. Children were seen to double their Schmid-Giovannini scores at 6 months postimplantation. CONCLUSIONS: The Essen outpatient-based cochlear implant program demonstrates results in speech development and speech understanding equal to those of centers providing inpatient rehabilitation. A special advantage is continuous rehabilitation with professionals known to the child for several years. In children especially, exhaustive commuting reduces school attendance and is a burden on the accompanying guardians. As an inpatient, however, the child is torn from his familiar environment. Parents with several children have particular difficulties in accompanying their child and indeed this may not always be possible.

Adult↗

[Immunohistochemical detection of humoral autoantibodies in patients with hearing loss in the last hearing ear].

BACKGROUND: An autoimmune etiology similar to the sympathetic ophthalmia has been discussed for sensorineural hearing loss on the last hearing ear following deafness in the first ear. In sympathetic cochleolabyrinthitis inner ear proteins are thought to be released after laterobasal fracture, which may induce an autoimmune process in the last hearing ear. Animal models have failed to clearly demonstrate the location of the target in the labyrinth, attacked by immunologic processes. Furthermore, it is unclear whether the humoral or cellular pathway is initiating this process. METHODS AND PATIENTS: Serum was acquired from 15 patients with traumatic or post-inflammatory unilateral deafness and slowly progressive or sudden sensorineural hearing loss on the last hearing ear. Deparaffinized sections of rat temporal bones were incubated with patient serum and subjected to immunohistochemical examination. RESULTS: A specific but heterogeneous binding pattern of the labyrinth was found in 14 of 15 patients. CONCLUSION: Our results indicate different autoantibodies in the patient serum, which may be the cause of the hearing loss. Therefore, in patients with sensorineural hearing loss on the last hearing ear, we recommend a therapeutic trial with corticosteroids.

Adrenal Cortex Hormones↗

[Paraffinoma--a rare complication following endonasal surgery].

BACKGROUND: Paraffin is a mineral oil which was discovered by Reichenbach in 1830. Injection of paraffin into tissue causes a foreign body reaction that results in the formation of a paraffinoma. METHODS: We are reporting on two cases of paranasal paraffinomas, in a 30-year-old male three months after a septorhinoplasty in which paraffin nasal packing was used and in a 56-year-old female patient two months after sinus surgery. RESULTS: A paraffinoma is probably caused by penetration of paraffin through a mucous membrane defect into the adjacent soft tissue. Paraffinomas are usually treated by excision. Although recurrences are frequent, a complete removal should be attempted because of the potential carcinogenicity of paraffin. CONCLUSION: Paraffinomas must be considered in the differential diagnosis of periorbital or paranasal swellings that occur months after endonasal procedures where paraffin packing was used.

Adult↗

New aspects in the histopathology of the cochlear aqueduct in children.

OBJECTIVE: To study the histoanatomy and pattern of growth of the cochlear aqueduct in children of different ages. BACKGROUND: Since Du Verney described the cochlear aqueduct in 1684, its form, pattern of growth, patency, and function have been controversial. As most of the previous studies of the aqueduct were performed on adults, none had looked at its pattern of growth from the neonate to 9 years of age. In addition, previous histologic studies had suggested an age-dependent patency, but recent investigations had not statistically correlated patency with age. METHOD: Histologic sections of 137 temporal bones from 79 infants and children were studied by light microscopy. From this group, we selected 32 temporal bones from 18 infants, newborn to 9 years (average age 9.1 months, median 0.5 months), in whom the entire length of the cochlear aqueduct was visible on one histologic section. We measured the width of the orifices at the scala tympani (external aperture) and the subarachnoid space (internal aperture) and the length of the aqueduct, and noted the contents of the lumen. RESULTS: The measurements of the cochlear aqueduct were: length 4.19 mm (range 1.7-10.7 mm), width of the external aperture 435 microm (range 225-869 microm), width of the internal aperture 1,323 microm (range 699-2344 microm), mean diameter of the narrowest part (isthmus) 138 microm (range 68-244 microm), intraluminal mononucleated cells 6%, and erythrocytes 15%. CONCLUSIONS: Our findings demonstrate that, in the newborn, the cochlear aqueduct is short and patent. After birth, the duct lengthens significantly primarily by growth of the medial periosteal portion. There was no statistically significant change in the diameter of the external and internal apertures and the isthmus with age. With one exception, the cochlear aqueduct was always present and patent.

Adult↗

The cochlear aqueduct in pediatric temporal bones.

The cochlear aqueduct is a bony channel which contains the fibrous periotic duct and connects the perilymphatic space of the basal turn of the cochlea with the subarachnoid space of the posterior cranial cavity. Previous histological studies suggested that patency depended on age, whereas a more recent study showed no statistical correlation between age and patency. To clarify patency in pediatric cochlear aqueducts, we selected 21 temporal bones from 12 infants and children, varying in age from birth to 9 years, in which the cochlear aqueduct was fully visible on one histological section. Photographs were taken for documentation and the length and width of the orifice of the external aperture of the aqueduct at the scala tympani were measured and followed to the internal aperture at the subarachnoid space. The lumen of the duct was examined for mononucleated cells, blood cells and fibrous tissue. Measurements revealed that the mean length of the cochlear aqueduct was 4.6 mm (range, 2.4-10.7 mm), mean width of the external aperture was 484 microm (range, 225-869 microm), and mean width of the internal aperture was 1293 microm (range, 699-2344 microm). The mean diameter of the narrowest part (isthmus) was 151 microm (range, 75-244 microm). In all temporal bones the cochlear aqueduct was patent, with one exception. This latter temporal bone was from a 2-month-old girl with multiple intralabyrinthine anomalies, with the missing cochlear aqueduct believed to be due to an aplasia. Our results support prior measurements of the cochlear aqueduct and demonstrate a short and patent cochlear aqueduct in newborns. With growth, a significant increasing length of the duct was found.

Aging↗

Herpes simplex virus type I reactivation as a cause of a unilateral temporary paralysis of the vagus nerve.

Infection by neurotropic viruses, as exemplified by the herpes family, is universally accepted as a cause of palsies of the cochleo-vestibular and facial nerve. Palsies of the vagus nerve with a possible viral etiology have been described, although viruses have been identified in only a few selected cases. We report a 52-year-old man with unilateral otalgia, hoarseness and dysphagia. Examination revealed unilateral (left-sided) pharyngeal dysfunction, and paralysis of the left vocal cord fixed in the paramedian position. A barium swallow documented dysfunction of the left pharyngeal constrictor muscles. These findings suggested the lesion to be located either at the inferior ganglion of the vagus nerve or cranially. At direct laryngoscopy a smear was obtained from a 4-mm mucosal ulcer at the region of the left arytenoid cartilage. This smear demonstrated antibodies to herpes simplex virus (HSV) type I by immunofluorescence. On follow-up 19 months after the initial infection there was complete remission of the paralysis of the left vocal cord and normal pharyngeal function. The demonstration of HSV type 1 antibodies from a mucosal lesion in the distribution of the superior laryngeal nerve suggests that reactivation of HSV type I was the most likely explanation for the temporary nerve palsy seen.

Antibodies, Viral↗

The utriculo-endolymphatic valve in pediatric temporal bones.

The utriculo-endolymphatic valve (UEV) is located in the posterior wall of the utricle at its junction with the utricular duct and was first described in a human fetus by Bast in 1928. Although different theories about its normal position and function have been postulated, the function of the UEV remains unclear. In the present investigation we studied 118 temporal bones from 70 children to determine whether there were differences in the position of the valve and by inference, its function between children and adults. Premortem ages ranged from newborn to 10 years (mean age, 11.6 months). All temporal bones were fixed in 10% formalin, decalcified and processed by the celloidin technique. Specimens were sectioned in a horizontal plane at a thickness of 20 microns. Every tenth section was stained with hematoxylin-eosin and studied by light microscopy. The position of the UEV was then classified as closed or open. Valves damaged by preparation or having an uncertain position were classified as artifact. The chi-square test was used to determine a correlation between the position of the valve and the status of the rest of the endolymphatic system and whether or not endolymphatic hydrops was present in the cochlear and vestibular systems. The UEV was closed in 39 temporal bones (33.1%) and open in 13 (11.0%). Artifacts were found in 66 bones (55.9%). In the group of patients with a collapsed ductus reuniens the UEV was closed in 38% of the specimens, suggesting that the UEV prevented loss of endolymph from the pars superior, but these findings were not statistically significant.

Artifacts↗

Temporary unilateral amaurosis with pneumosinus dilatans of the sphenoid sinus.

Pneumosinus dilatans (PSD), first described by Meyes in 1898, is an abnormal dilatation of one or more of the paranasal sinuses without bony erosion. The term sinus pneumocele indicates the presence of bony erosion. Review of the literature from 1968 to 1992 revealed 24 cases of idiopathic PSD and 17 cases of pneumocele of various paranasal sinuses. PSD occurred most commonly in the frontal sinus. Males were more often affected than females. The average age for males ranged from 16.5 for the maxillary sinus to 35.5 years for the sphenoid sinus. Pneumoceles occurred most commonly in the maxillary sinus. The average age for males ranged from 29 years for the frontal sinus and 47 years for the ethmoid sinus. Two patients (1 pneumocele and 1 PSD) had a temporary loss of vision. We report the case of a 37-year-old mountain climber who experienced temporary loss of vision in his left eye above 3000 m. Vision returned below 2000 m. High resolution computed tomography scan revealed pneumosinus dilatans of the sphenoid sinus with dehiscence of the optic canal on the left side. Endonasal microendoscopic resection of the anterior wall of the left sphenoid sinus was performed. The patient has remained symptom-free after 2 years of follow-up. Pneumosinus dilatans should always be considered in the differential diagnosis of sudden visual loss associated with atmospheric pressure changes.

Case Reports↗

Stimulus-inadequate sensations in cochlear implant patients.

From August 1984 to April 1987 the Department of Otolaryngology at the Medizinische Hochschule in Hannover implanted the NUCLEUS 22 channel cochlear implant system (CI) in their first 56 adults. Since implantation, 27 (51%) patients have described undesirable sensations from their implant. These were defined as stimulus-inadequate sensations (SIS) and were classified into three types: 1) pain-like sensations; 2) high-frequency sensations; and 3) non-stimulation. Twenty-three patients were radiographically investigated by polytomography. All of the intracochlear electrodes were visualised and a correlation between SIS and the radiological findings was established. It was found that i) SIS similar to pain are caused by electrical stimulation of the mucous membranes and periosteum of the tympanic cavity; ii) the high-frequency SIS seemed to be due to non-physiological electrical stimulation of the basal ganglion cells; and iii) the reason for non-stimulation is probably damaged electrodes and fibrosis around the electrode. Conventional tomography is the method of choice for estimating the number and configuration of intracochlear electrodes.

Adolescent↗