Disease relevance of Neuroma, Acoustic

• Neurofibromatosis 2 (NF2) features bilateral vestibular schwannomas, other benign neural tumors, and cataracts [1].
• Surgical and histological studies have shown that vestibular Schwannomas of NF2 patients are more invasive than sporadic Schwannomas and that the two groups also have morphological differences [2].
• All tumors showed staining with an antibody to a C-terminal peptide of neurofibromin, confirming that full-length neurofibromin is present in these vestibular schwannomas, meningiomas, and ependymomas [3].
• Neurofibromatosis 2 (NF2), a dominantly inherited disorder, is typically manifested as bilateral vestibular Schwannomas and predisposes to other nervous system tumors [2].
• It is concluded that CT is the technique of choice in patients suspected of having acoustic neuromas or malignant tumors of the temporal bone, while hypocycloidal tomography should be used to evaluate pateints with otosclerosis, small cholesteatomas, and inflammatory disease of the middle ear [4].

Psychiatry related information on Neuroma, Acoustic

• Acoustic tumors: operation versus radiation--making sense of opposing viewpoints. Part I. Acoustic neuroma: decision making with all the tools [5].
• Reports in the literature suggest that patients with otosclerosis, neural lesions such as acoustic neuroma, pontine lesions, and temporal lobe lesions may show abnormal sound localization ability [6].

High impact information on Neuroma, Acoustic

• NF2 is a dominantly inherited disease characterized by the formation of bilateral acoustic schwannomas and other benign tumors associated with the central nervous system [7].
• There was no difference, however, in tissue-type plasminogen activator antigen levels among control, benign, or malignant tissues except for a 4- to 7-fold increase in acoustic neuroma [8].
• Neurofibromatosis type 2 (NF2) is a rare autosomal dominant disorder characterized by the occurrence of bilateral vestibular schwannomas, various brain and spinal tumours as well as peripheral nerve tumours, cutaneous tumours and juvenile posterior lenticular opacity [9].
• Elevated expression of basic fibroblast growth factor messenger ribonucleic acid in acoustic neuromas [10].
• Age does not explain the detected difference in proliferation, since NF2 vestibular Schwannomas also had higher MIB-1 indices than 34 age-matched sporadic tumors [2].

Chemical compound and disease context of Neuroma, Acoustic

• Nonneoplastic enhancing lesions mimicking intracanalicular acoustic neuroma on gadolinium-enhanced MR images [11].
• The radiologic investigation of patients with suspected acoustic neurilemmomas may include specialized plain films, thin-section tomography, CT scanning with intravenous contrast enhancement, Pantopaque cisternography, radionuclide scanning, angiography, and pneumoencephalography [12].
• CONCLUSION: Proton beam stereotactic radiosurgery of vestibular schwannomas at the doses used in this study controls tumor growth with relatively few complications [13].
• Dural "tail" associated with an acoustic schwannoma in MR imaging with gadopentetate dimeglumine [14].
• To assess whether relatively prolonged anesthesia with N2O in normal patients might similarly cause untoward effects, we investigated whether the addition of N2O to isoflurane anesthesia caused injury to patients having surgical resection of acoustic neuroma lasting approximately 10 h [15].

Biological context of Neuroma, Acoustic

• Age dependent phosphorylation and deregulation of p53 in human vestibular schwannomas [16].
• BACKGROUND: Although mutational inactivation and allelic loss in the NF2 gene appear to be causal events in the majority of vestibular schwannomas, involvement of another potentially important mechanism, transcriptional inactivation, has not been investigated [17].
• In patients with vestibular schwannomas (VSs) or identified NF2 mutations, the mild phenotype was defined as < 2 other intracranial tumors and < or = 4 spinal tumors, and the severe phenotype as either > or = 2 other intracranial tumors of > 4 spinal tumors [18].
• The maintained expression of the PTEN protein, together with the lack of detectable mutations in this gene, suggests that the function of the PTEN tumour suppressor gene is not altered in sporadic vestibular schwannomas [19].
• Recent introduction of O2 computed tomography cisternography and imaging with high resolution program have greatly improved the detection and preoperative evaluation of acoustic neuromas and other possible pathologies of the internal auditory canal [20].

Anatomical context of Neuroma, Acoustic

• Proteolipid mRNA was identified in human acoustic neuromas and in rat and rabbit sciatic nerves using a human PLP cDNA as a probe [21].
• The authors present the clinical, radiological, pathological features, and autopsy findings of a patient with malignant triton tumor of the acoustic nerve, which probably arose from a pre-existing acoustic schwannoma [22].
• Interface between the facial nerve and large acoustic neurinomas. Immunohistochemical study of the cleavage plane in NF2 and non-NF2 cases [23].
• PATIENTS AND METHODS: Postoperative gadolinium-enhanced exams of 13 of 44 patients who underwent excision of acoustic neuromas via the middle cranial fossa approach were reviewed [24].
• By immunohistochemistry, the p75 receptor was found to be the present at high levels in Schwann cells from acoustic schwannomas, whereas it was very weak or absent in MPNST [25].

Gene context of Neuroma, Acoustic

• Constitutive neuregulin-1/ErbB signaling contributes to human vestibular schwannoma proliferation [26].
• The CYP2E1 RsaI variant was weakly associated with glioma (OR, 1.4; 95% CL, 0.9, 2.4) and acoustic neuroma (OR, 2.3; 95% CL, 1.0, 5.3), with some indication of stronger associations among younger subjects [27].
• Gastrin, cholecystokinin and their precursors in acoustic neuromas [28].
• Neurofibromas showed consistently high numbers of CD34-positive spindle cells, whereas peripheral and acoustic schwannomas were negative [29].
• CONCLUSIONS: The pRb-CDK pathway was altered in all vestibular schwannoma tumors examined, with CDK2 significantly downregulated in seven of the eight tumors [30].

Analytical, diagnostic and therapeutic context of Neuroma, Acoustic

• EEG features associated with the occurrence of epilepsy after surgery for intracranial aneurysm and acoustic neuroma [31].
• CONCLUSIONS: Our study indicates that recurrent vestibular schwannomas treated with GKR have lower proliferation potential as assessed by PCNA compared with recurrences following microsurgery [32].
• Five patients with unilateral acoustic neuromas were studied with CT before and after treatment with dexamethasone [33].
• CONCLUSIONS: This retrospective study showed no apparent benefit from intraoperative steroid use in acoustic neuroma surgery [34].
• DESIGN--DNA flow cytometry techniques were used to evaluate formalin-fixed, paraffin-embedded tissue previously obtained from patients who were surgically treated for acoustic neuromas [35].

References