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At least 721 records · Page 40Linked to original sources
PubMed1989

Hereditary sensory neuropathy with deafness: a familial multisystem atrophy.

We report a 39-year-old woman with hereditary sensory neuropathy-type I (HSN-I) and deafness--Hicks' disease. The cochlea showed cell loss in the organ of Corti, and spiral ganglia and atrophy of acoustic nerves. Morphometric and quantitative studies of the ventral cochlear nucleus disclosed mild changes resulting from transynaptic atrophy. There was, however, neuronal as well as severe dendritic loss and gliosis in the auditory and sensory cortex that could not have been caused by their functional deprivation or have resulted from a chain reaction of transynaptic atrophy, since their corresponding lower relay nuclei did not display significant atrophy. The finding of cell loss and gliosis in the thalamus in nuclei that do not subserve these two pathways as well as in the red nuclei, inferiro olivary nuclei, and claustrum suggested that HSN-I with deafness is nosologically related to familial multisystem atrophy.

Adult↗
PubMed1992

Neurinomas presenting as spontaneous intratumoral hemorrhage.

Massive intratumoral or subarachnoid hemorrhage from neurinomas is very rare. The authors report on six patients, four men and two women, with neurinomas that presented as spontaneous intratumoral hemorrhage. The average age of the patients was 56.8 years (range, 31-74 years). Neurinomas originated from the acoustic nerve in four patients and from the trigeminal nerve in two. Four cases were accompanied by the sudden occurrence of clinical symptoms such as headache, double vision, and hemisensory or motor disturbance. The maximum diameter of the tumors ranged from 2.8 to 3.8 cm (average, 3.1 cm). Histological examinations showed massive hemorrhage and increased vascularity, with dilated, thin-walled vessels, in all cases. The size of the tumor and the increase in vascularity with dilated, thin-walled vessels within neurinomas are important pathogenetic factors of hemorrhage. When sudden onset of symptoms or rapid worsening of chronic symptoms occurs in neurinomas, intratumoral or subarachnoid hemorrhage should be considered as a possible cause, and magnetic resonance imaging can be an important tool in obtaining correct diagnosis.

Adult↗
PubMed1992

S-100 protein in human inner ear: use of a novel immunohistochemical technique on routinely processed, celloidin-embedded human temporal bone sections.

The authors recently developed a new antigen retrieval technique which allows immunohistochemical detection of proteins in routinely processed, celloidin-embedded human temporal bone sections. This technique was used in the present study, which reports the occurrence of S-100 protein in the human inner ear. Fifteen celloidin-embedded human temporal bone sections, obtained from the Eastern Temporal Bone Bank at the Massachusetts Eye and Ear Infirmary, were tested with the monoclonal antibody to S-100. This protein was found in the spiral ligament, in Reissner's membrane, in the spiral limbus, and in the basement membrane of the cochlea. S-100-positive, thin fibers could be seen as supporting elements in the acoustic nerve and the facial nerve. This protein was localized along the surface of vestibular wall. The new technique provides an immunohistochemical approach to studying routinely processed human temporal bone sections and may prove useful in the field of immuno-otopathology.

Collodion↗
PubMed1996

Three-step immunoscintigraphy with anti-chromogranin A monoclonal antibody in tumours of the pituitary region.

In the present paper we evaluated the ability of pretargeted immunoscintigraphy (ISG) with antichromogranin A (CgA) monoclonal antibody (Mc-ab A11) in visualizing pituitary masses. The results obtained in 23 patients are described along with those of [111In]pentetreotide scintigraphy (Octreoscan) in 18 cases. Positive ISG was obtained in 9/11 (82%) non-functioning, 1/4 growth hormone-, 1/2 prolactin-, 1/2 thyrotropin-, 1/1 follicle-stimulating hormone-, 0/1 adrenocortico-trophin-secreting pituitary adenomas. In one patient with a positive ISG scan of a non-functioning pituitary adenoma, an associated neurinoma of the acoustic nerve was not imaged. The same occurred in one patient with a pituitary deposit from a mammary carcinoma and in another one with a cyst of the Rathke's pouch. Chromogranin A immunohistochemistry, carried out in 10 tumours, was positive in eight pituitary adenomas and negative in two non-adenomatous lesions. A concordant ISG occurred in all cases except for two pituitary adenomas: one cystic and necrotized and one post-operative remnant very small in size. In 18 patients with pituitary adenoma both ISG and Octreoscan were positive in 61% of cases but with a different distribution among tumours. At variance with ISG, Octreoscan visualized only 5/10 (50%) non-functioning pituitary adenomas and all (4/4) somatotropinomas. In conclusion, ISG is able to image pituitary tumours and particularly non-functioning pituitary adenomas. In this respect, it may be helpful in discriminating non-neuroendocrine masses of the pituitary region from non-functioning pituitary adenomas.

Adolescent↗
PubMed2002

Cellular regulatory mechanisms influencing the activity of the cochlear nucleus: a review.

The cochlear nucleus is the site in the auditory pathway where the primary sensory information carried by the fibres of the acoustic nerve is transmitted to the second-order neurones. According to the generally accepted view this transmission is not a simple relay process but is considered as the first stage where the decoding of the auditory information begins. This notion is based on the diverse neurone composition and highly ordered structure of the nucleus, on the complex electrophysiological properties and activity patterns of the neurones, on the activity of local and descending modulatory mechanisms and on the presence of a highly sophisticated intracellular Ca2+ homeostasis. This review puts emphasis on introducing the experimental findings supporting the above statements and on the questions which should be answered in order to gain a better understanding of the function of the cochlear nucleus.

Animals↗
PubMed2006

Diffuse large B-cell lymphoma arising in a patient with neurofibromatosis type I and in a patient with neurofibromatosis type II.

We experienced two unusual cases of diffuse large B-cell lymphoma (DLBCL), which occurred in a patient with neurofibromatosis type I and a patient with neurofibromatosis type II. B-cell lymphoma is one of the most common phenotypic subgroups of malignant lymphoma. Neurofibromatosis I is characterized by café-au-lait spots and neurofibromas. Neurofibromatosis II typically consists of bilateral schwannomas of the acoustic nerve. Malignant lymphomas rarely coexist with neurofibromatosis I, and no coexistence with neurofibromatosis II has been reported. The patient with neurofibromatosis I was a 50-year-old Japanese woman, clinically manifesting von Recklinghausen's disease since infancy, who noticed an egg-sized tumor in her shoulder. The patient with neurofibromatosis II was a 39-year-old Japanese man who noticed multiple soft tissue tumors in his neck, buttock, and elbow. Biopsied materials from both cases were examined by multiparameter methods, including flow cytometry. Flow cytometry revealed large-scale cells to be tumor cells, and they were positive for CD19, CD20, and CD22. Both patients received chemotherapy, and the tumors disappeared. The patient with neurofibromatosis I was alive without recurrence at 4 years after treatment, while the patient with neurofibromatosis II died of recurrence. To the best of our knowledge, this is the first case of malignant lymphoma arising in a neurofibromatosis II patient. As for neurofibromatosis I, there were some reports about occurrence of malignant lymphoma. It is important to be aware of possibility of association of malignant tumors not only of the nervous system but also of unrelated to the nervous system when tumors appear in neurofibromatosis patients.

Adult↗
PubMed1998

Facial spasm and paroxysmal tinnitus associated with an arachnoid cyst of the cerebellopontine angle--case report.

A 59-year-old female presented with a 3-year history of hemifacial spasm and paroxysmal tinnitus associated with an arachnoid cyst of the cerebellopontine angle, which was identified preoperatively by magnetic resonance imaging. Surgical decompression of the cyst and arterial decompression of the facial and acoustic nerves at their root exit zones resulted in complete resolution of the symptoms.

Arachnoid Cysts↗
PubMed2001

Brainstem frequency-following response recorded from one vertical and three horizontal electrode derivations.

The human brainstem frequency-following response reflects neural activity to periodic auditory stimuli. Responses were simultaneously recorded from one vertically oriented and three horizontally oriented electrode derivations. Nine participants each received a total of 16,000 tone repetitions, 4,000 for each of four stimulus frequencies: 222, 266, 350, and 450 Hz. The responses were digitally filtered, quantified by correlation and spectral analysis, and statistically evaluated by repeated measure analysis of variance. While the various horizontal derivation responses did not differ from each other in latency (values tightly clustered around M= 2.60 msec.), the vertical derivation response occurred significantly later (M=4.38 msec.). The smaller latency for the horizontal responses suggests an origin within the acoustic nerve, while the larger latency for the vertical response suggests a central brainstem origin. The largest response amplitude resulted from gold "tiptrode" electrodes placed in each auditory meatus, suggesting that this electrode derivation provided the most accurate (noninvasive) assessment of short-latency events originating at the level of the auditory nerve.

Adult↗
PubMedDate not supplied

Audiological findings in 125 cases of acoustic neuromas.

The audiological findings in 125 patients with surgically confirmed acoustic neuromas are presented. Following the classification by Pulec et al. (1971) we found 20 medium-size and 105 large tumours; small tumours were not represented. A clear connection between the degree of hearing loss and tumour size was noted, while there was no correlation between duration of history and tumour size. An attempted evaluation of the different audiological tests (ABLB and Metz recruitment test, speech discrimination scores, tone decay, reflex decay, and Békésy tracings) that were applied to the patients, has been made. Attention is called to some audiological findings which, to our knowledge, have not been described previously. No patient in the entire material had normal hearing; 73 had anacusis, and 52 hearing losses of varying degree. In the presence of a normal contralateral ear, the evaluation of audiological tests at PTA thresholds poorer than 80 dB is rather questionable. Attention was therefore concentrated on 32 patients with a hearing loss of 80 dB or less. The pathophysiological basis for the typical hearing loss in patients with retrocochlear disease is a reduction in the number of active fibers in the acoustic nerve and it was to be expected that abnormal findings would be present especially in those tests that exert the greatest demand on the total transmission capacity of the nerve, in other words with the application of intense and/or prolonged sounds. The Metz test is just such a procedure and it is not surprising that it shows the highest degree of validity between all the tests. No single test suffices to distinguish cochlear from retrocochlear disease and it is necessary to use a battery of tests. Any unexpected variability in the outcome of ordinary routine test results has gradually become one main indication to pursue the diagnosis with more elaborate procedures, ant it has been a great help always to apply the Metz test as a part of our routine clinical examination.

Adult↗
PubMed1995

Morphologic and morphometric study of human spiral ganglion development.

A light microscopic study of the spiral ganglion was done in human embryos and fetuses measuring 45, 50, 60, 74, 90, 134, 270 mm crown-rump length (crl), and in a one-day-old neonate. Morphometric evaluations of i) cell and nuclear area, ii) nuclear area/cell area ratio, iii) ganglion area, iv) cell concentration/surface unit, and v) distance between the first neuron and the receptor were made, and the results statistically evaluated. In earlier stages of development, spiral ganglion primordia appeared as a cluster of neuroblasts and some schwannoblasts immersed in the mesenchymal tissue, close to the ductus cochlearis. A honeycomb pattern in the spiral ganglion neurons was observed in the basal turn of a 74 mm crl fetus. In later stages, the basal turn of a 90 mm crl fetus showed a spatial organization. Peripheral and central fibers of the acoustic nerve appeared stratified in early periods of development (45 mm crl embryo). From this stage on, both phenomena progress apicalwards until the neonatal period. A significant decrease in the nuclear area/cell area ratio was observed from the 134 mm crl fetus (17 weeks) to the neonatal stage in all turns. This led to a significant increase in cellular area from the 270 mm crl fetus (32 weeks) to the neonate, with no significant variation in nuclear area. The distance from the primordium of the organ of Corti to the spiral ganglion in the interval between 45 and 74 mm crl showed a significant increase in all turns.(ABSTRACT TRUNCATED AT 250 WORDS)

Cochlear Duct↗
PubMed1987

Clinical and electrophysiological studies in a patient with keratitis, ichthyosis and deafness (KID) syndrome.

Neurological studies were performed in a young boy with keratitis, ichthyosis and deafness syndrome. Skin biopsy showed features of ichthyosis. Clinically and electrophysiologically, he had normal motor and sensory systems, but there was an acoustic nerve lesion and absence of tendon reflexes. Audiometry and brainstem auditory evoked potentials showed bilateral neurosensory deafness. Poor vision may not be due to an optic nerve lesion as evidenced on visual evoked potential findings, but is probably due to pronounced vascularizing keratitis of the cornea. Computer tomography scan showed mild hypoplasia of the inferior vermis and left side of the cerebellum.

Blinking↗
PubMedDate not supplied

[Electrophysiological study of cochlear damage in early otosclerosis and after stapedial surgery].

Otoesclerotic patients usually have neurosensorial hearing toss in addition to a predominantly conductive impairment, but there is no universally accepted explanation for this abnormality. The bone conduction threshold in tonal audiometry is accepted as a test of cochlear function. An early evaluation of damage to the cochlea arid acoustic nerve after surgery was made by studying 99 ears with BERA and latency/intensity curves to test cochlear function. We concluded that early damage was present. Postoperative cochlear damage was found in spite of successful surgery, but it was no greater than the damage present before surgery.

Audiometry, Pure-Tone↗