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At least 19 recordsLinked to original sources
PubMedDate not supplied

Cerebellopontine angle tumours, other than acoustic neuromas. A report on 34 cases. A presentation of 7 bilateral acoustic neuromas.

The symptoms, preoperative diagnostic results and histological findings in 34 cerebellopontine angle tumour cases, other than acoustic neuromas, are presented. The meningeomas dominate by far this group of tumours. The symptomatology is much less uniform than that of the acoustic neuromas, where the VIII nerve is dominant. The facial nerve is less involved, whereas the other cranial nerves give symptoms more frequently. One remarkable sign is the presence of severe trigeminal neuralgia, which we have not encountered in acoustic neuromas. Only 35% of the 'non-neuroma' patients had elevated spinal fluid protein, compared with 100% in our acoustic neuroma cases. Furthermore, 7 patients with bilateral acoustic neuromas are presented. The connection with von Recklinghausens disease and multiple meningeomas is discussed.

Adult↗
PubMed1976

Comparative ultrastructure of thyroid, tongue and eyelid lesions in the neuroma phenotype of medullary carcinoma of the thyroid: association of amyloid with fibroblasts in thyroid tumor and in mucosal neuromas.

Electron-microscopic and histochemical studies of thyroid tumor, tongue neuromas and eyelid neuromas from the lesions of a patient with medullary thyroid carcinoma were compared. In the thyroid tumor, a significant number of the C cells showed heterogeneity of granule types; no C cells, however, were identified in the tongue and eyelid neuromas. Amyloid was clearly shown by Congo red staining in the thyroid neoplasm and in the tongue neuromas. In all tissues, amyloid fibrils were found to be ultrastructurally closely associated with fibroblasts. These fingings suggest that the fibroblast rather than the C cell may have played the important role in the deposition of amyloid in this patient's thyroid carcinoma.

Amyloid↗
PubMed1977

The ultrastructure of oral neuromas in multiple mucosal neuromas, pheochromocytoma, medullary thyroid carcinoma syndrome.

The ultrastructure of oral neuromas from 2 patients with multiple mucosal neuromas, pheochromocytoma, medullary thyroid carcinoma syndrome reveals numerous hypertrophic unmyelinated and myelinated axons, hyperplastic neurilemmal cells and associated collagen fiber formation. These tumors are described and compared ultrastructurally with neurilemmomas and neurofibromas as described by other authors. On the basis of this comparison, these tumors are not considered to be of neurilemmal origin. On the basis of light and electron microscopic histology it is postulated that these tumors represent hypertrophy of axons similar to that noted in amputation neuromas.

Adolescent↗
PubMedDate not supplied

Sonographic analysis of Morton's neuroma.

A prospective study was performed whereby 73 patients exhibiting clinical symptoms of 109 Morton's neuromas were examined using ultrasound. Reproducible hypoechoic densities were identified as neuromas if they measured greater than 5 mm. in transverse dimension, with those 4 mm. or less in dimensions called "suspicious" if they were well-defined and if the patient had marked pain in the examined interspace. Sixty of the neuromas were surgically excised, with 49 being managed conservatively. Of the surgical cases, all but three (95%) of the neuromas were positively identified on sonographic examination and all excised masses demonstrated pathological findings consistent with Morton's neuroma. Thirty-nine percent of the conservatively treated neuromas were negative on sonogram. The average sonographic size of the resected neuromas was 6.2 mm., while the size of those not resected averaged 4.9 mm. This study provides evidence that preoperative sonography is an additional aid in the evaluation of Morton's neuroma, and reaffirms previous evidence that symptomatic neuromas are likely to be at least 5 mm. in diameter on sonogram.

Adult↗
PubMed1975

The occurrence and characteristics of non-myelinated neuromas within central nervous tissue.

Three cases are described in which neuromas composed of non-myelinated axons were present within central nervous tissues in areas of tissue destruction, together with neuromas of peripheral myelinated axons. The non-myelinated neuromas were larger than the myelinated, but contained very much fewer Schwann cells and less connective tissue fibers. It is suggested that they took origin from heterotopic non-myelinated peripheral nerves, just as the myelinated neuromas are thought to take origin from heterotopic myelinated peripheral nerves. The non-myelinated neuromas are very much less common than the myelinated neuromas, and the inference may be drawn that their nerves of origin may be very much less common, a malformational rarity. Because of their rarity, and the very limited proliferation of Schwann cells which follow their injury, these non-myelinated perivascular nerves are not likely to provide the Schwann cells which produce the regenerated peripheral myelin about some denuded but perserved central axons in myltiple sclerosis. These may take origin from multipotential primitive reticular cells within the central nervous tissues, as is consistent with the thesis perviously offered that Schwann cells are mesenchymal in character. It may also be inferred that any neurogenic control of cerebral circulation would be limited to an effect on the larger, extracerebral vessels in the subarachnoid space.

Aged↗
PubMed1978

Immunologic detection of acoustic neuroma: preliminary report.

In an attempto to provide preoperative histologic identification of internal auditory canal and cerebellopontine angle tumors, and to attempt to detect small tumors and recurrent tumors, immunologic aspects of acoustic neuroma patients and control subjects were studied. Reactions based upon the interaction of patients' fresh lymphocytes in contact with acoustic neuroma antigens were studied by a leukocyte migration inhibition (LMI) assay and a locally developed refinement, the plasma effect assay. These were performed either preoperatively, postoperative, or both, in 17 patients with surgically confirmed acoustic neuromas and in 24 controls subjects. Preoperative tumor patients had a higher likelihood of having elevated LMI and plasma effect assay values than normals. False positive results were rare and the combination of the LMI and plasma effect assay decreased false negative responses to 20%. Meaningful conclusions must await more extensive testing but it has been demonstrated that tumor associated antigens do exist on the membranes of schwannoma cells and that most patients with an acoustic neuroma mount a cell-mediated immune response against these antigens.

Antigens, Neoplasm↗
PubMed1992

Growth of human acoustic neuromas, neurofibromas and schwannomas in the subrenal capsule and sciatic nerve of the nude mouse.

To develop a reproducible in vivo model for the growth of human acoustic neuromas and neurofibromas, we implanted tumor specimens (6 acoustic neuromas; 4 neurofibromas; 3 schwannomas arising in skin and soft tissues) from 13 different patients into the subrenal capsules of 67 nude mice and sciatic nerves of 64 nude mide. The animals were anesthetized and the tumors were microscopically implanted. Serial tumor volumes were determined at intervals up to 2 months by reopening the incision and directly measuring the tumor size with a micrometer. The percentages of acoustic neuromas that survived or grew were 57.1% in the subrenal capsule and 88.9% in the sciatic nerves; the percentages of neurofibromas that survived and grew were 50% in the subrenal capsule and 70% in the sciatic nerves; and the percentages of schwannomas that survived and grew were 57.1% in the subrenal capsule and 94.1% in the sciatic nerve. Tumors in the sciatic nerve also survived and grew for a longer period than those in the subrenal capsules. Tumor enlargement and stability correlated with neovascularity. At 1 or 2 months after engraftment, the tumors showed histologic appearances similar to the original tumors and immunohistochemical analysis of cryostat sections demonstrated staining of the tumors, but not the host mouse tissues for human beta 2-microglobulin, a species-specific marker. Furthermore, analysis of genomic DNA from implanted tumors revealed its human origin. We conclude that human acoustic neuromas, neurofibromas and schwannomas are readily grown in two sites in nude mice and that they retain their morphologic features and genomic identities. These tumors grow better and more consistently in the sciatic nerve than in the subrenal capsule. These are useful model systems for studying tumor growth and cellular modulation.

Animals↗
PubMed1992

A technique for the treatment of neuroma in-continuity.

A surgical technique for the management of a neuroma in-continuity, in which motor function is preserved and sensory function is reconstructed with nerve grafting, is presented. Tedious and potentially damaging dissection within the neuroma in-continuity is avoided. The functioning motor fascicles are identified proximal and distal to the injury site with electrical nerve stimulation eliciting muscle contraction. These motor fascicles are preserved. The electrically silent and nonfunctioning sensory fascicles are divided proximal and distal to the neuroma and reconstructed with autogenous nerve grafts. These nerve grafts bypass the functioning motor portion of the neuroma in-continuity.

Adult↗
PubMed1992

Axonal cross-excitation in nerve-end neuromas: comparison of A- and C-fibers.

1. We recorded from single afferent axons ending in chronic sciatic nerve end neuromas in rats with the use of the teased-fiber method. Axons were sought that had ongoing impulse discharge originating in the neuroma. 2. Recording from myelinated (A-) fibers, tetanic stimulation of neighboring axons (50 Hz, 5 or 10 s, intensity adequate to drive A-fibers) caused an increase, and sometimes a decrease, in the rate of ongoing discharge in 68% of the fibers tested. In addition, some initially silent neuroma A-fibers (1.4%) were activated in this way. Both A beta and A delta fibers responded, although the likelihood of response was greater in A beta fibers. We call this form of interfiber cross-excitation "crossed afterdischarge." 3. In contrast to A-fibers, crossed afterdischarge was evoked with these stimulation parameters in < or = 5% of the spontaneously active unmyelinated (C-) fibers sampled. No initially silent C-fibers were activated. 4. C-fibers remained largely insensitive to cross-excitation by neighboring axons even when the strength of stimulus pulses was increased so as to include neighboring A + C-fibers. 5. The difference between A- and C-fibers could not be accounted for on the basis of the maturity of the neuroma, rate and pattern of ongoing discharge, or use of Flaxedil paralysis. 6. The difference between A- and C-fibers is discussed in terms of two alternative mechanisms that may underlie crossed afterdischarge: mediation by a neurotransmitter(s) in a nonsynaptic mode, and mutual K+ depolarization.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

Recovery from repeated sudden hearing loss with corticosteroid use in the presence of an acoustic neuroma.

Sensorineural hearing loss of sudden onset may be the presenting symptom in up to 14% of patients with acoustic neuroma. We present the first reported case of sudden hearing loss in an only hearing ear with recovery to normal levels after steroid therapy on four separate occasions. Evaluation revealed a 1.5-cm acoustic neuroma. After middle cranial fossa decompression, a fifth episode with recovery after steroid use was documented. A review of the recent literature is presented, emphasizing the possible causation of sudden sensorineural hearing loss with recovery to normal in patients with acoustic neuroma. Modalities of therapy for the dilemma of the acoustic neuroma in an only hearing ear are discussed, including surgery, radiotherapy, and chemotherapy. An aggressive approach to the evaluation of the cause of sudden hearing loss is suggested.

Audiometry, Pure-Tone↗
PubMed1992

[Distorsion-products otoacoustic emissions in acoustic neuroma].

Eight cases with surgically confirmed 1.5-3.5 cm acoustic neuromas were tested through measuring distorsion-products otoacoustic emissions (DPO), which objectively reflects the cochlear status. Only one frequency (Ft) corresponding to behavior threshold highest dB HL is selected as a frequency site of DPO. The DPO is collected at a level of 75 dB SPL with equilevel of stimuli f1 and f2 and proper frequency separation (f2/f1 = 1.2). The frequencies of stimuli f1 and f2 can be calculated through the formula Ft=2f1-f2. Six cases with less than 3.0 cm neuromas had normal amplitude of DPO. Decreased amplitude of DPO is found in two cases suffered from 3.0-3.5 cm neuromas. The discrepancy between behavior threshold and amplitude of DPO can be an important indication for distinguishing early retrocochlear lesions, for instance, acoustic neuroma.

Adult↗
PubMed1977

Surgery of acoustic neuromas. Preliminary experience with a translabyrinthine approach.

Inspired by the works of William House, the authors formed an otoneurosurgical team in order to improve the results after surgery for acoustic neuromas. This paper deals with the preliminary results obtained with the translabyrinthine approach in 13 patients with acoustic neuromas. In 9 patients it was possible to remove the tumor totally with this approach, in 4 patients a second suboccipital operation was necessary to secure total removal. One small, 7 medium and 5 large tumors were encountered. The facial nerve was preserved in 83 per cent of the patients. One patient with a large tumor died after the second suboccipital operation. The relation between size of the tumor and the outcome of the operation is stressed, and in order to reduce the number of large tumors it is suggested that all patients with unilateral hearing loss should be suspected of having a neuroma, until the diagnosis has been disproved. It is concluded that the surgery for acoustic neuromas is otologic-neurosurgical teamwork, and that the treatment should be centralized.

Adult↗
PubMed1976

Intestinal ganglioneuromatosis with the mucosal neuroma --medullary thyroid carcinoma-- pheochromocytoma syndrome. A case report and review of the literature.

A case of intestinal ganglioneuromatosis associated with medullary thyroid carcinoma, bilateral pheochromocytoma, mucosal neuromas and marfanoid habitus is reported. To our knowledge, only ten previous cases of intestinal ganglioneuromatosis associated with mucosal neuromas and medullary carcinoma of the thyroid have been reported. Our case represents the 11th such case, the seventh with the concomitant finding of pheochromocytoma and the second with documented parathyroid hyperactivity. The intestinal ganglioneuromatosis may represent a variation of the mucosal neuroma component of this rare syndrome and the multiorgan abnormalities may result from a genetically related disorder of a single cell system, the neural crest. The characteristic marfanoid habitus with the presence of mucosal neuromas raises the possibility of a serious underlying polyendocrine-neural disorder and should alert the clinician accordingly.

Adult↗
PubMed1977

Traumatic neuroma of the nose.

We report a case of a traumatic neuroma of the nose. It was an unusual site for two distinct types of tissue response to skin and soft trauma that exceeded the reparative needs of the body. In the first instance, a small cutaneous nerve was sectioned, and its inability to establish continuity distally resulted in a neuroma. In the second instance, the excision site of the neuroma was reinjured, and an abnormal connective tissue response occurred, resulting in a hypertrophic scar or keloid. Both were treated similarly with excision, and ultimately with local steroid injection with satisfactory results.

Adolescent↗
PubMed1977

Auditory test results in 500 cases of acoustic neuroma.

Auditory test results in the first 53 causes of this series of 500 acoustic neuromas were reported in 1964. Subsequent studies involving larger numbers of patients detailed new results based on these additional cases. Five hundred cases of surgically confirmed acoustic neuromas were analyzed. Pure-tone loss configurations, speech discrimination, auditory adaptation as measured by the modified tone decay test, Bekesy audiometry, short increment sensitivity index test, and alternate binaural loudness balance test data were evaluated. The results of this investigation in general confirm previous studies, although percentage figures for positive tests differed in the large series. Acoustic reflex results were reported for those patients evaluated more recently. Slightly more than half of the cases had inconsistent audiometric results in one or more aspects. Inconsistencies to the tests were examined in detail. Consistent responses to the tests appear to be related to the size of the lesion. The full battery of audiologic tests is of importance in the differential diagnosis of acoustic neuromas.

Adolescent↗
PubMed1978

Computed tomography for small acoustic neuromas.

The minimal size of acoustic neuromas detectable by computered tomography (CT) is, according to the available literature, 1.5 to 2 cm. The new otoneurosurgical technic using the transtemporal and translabyrinthine approach necessitates an early diagnosis of neuromas protruding 1 cm or less into the cerebellopontine angle cistern. This seemed impossible with the available CT equipment. Eight proven acoustic neuromas 1 cm or less in diameter, detected with CT, are reported. Diagnostic criteria are elaborated. The study shows that small cerebellopontine angle tumors can be detected by use of CT machines of the newer generation which perform scanning with thin and overlapping slices.

Aged↗