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At least 19 recordsLinked to original sources

Chromosome arm 17p deletion analysis reveals molecular genetic heterogeneity in supratentorial and infratentorial primitive neuroectodermal tumors of the central nervous system.

The current World Health Organization (WHO) classification groups together both infratentorial neoplasms (medulloblastomas) and their supratentorial counterparts as primitive neuroectodermal tumors (PNETs), implying a common origin. Previous analyses of medulloblastoma have shown loss of chromosome arm 17p as the most frequent genetic abnormality: the molecular genetic constitution of supratentorial PNETS has not been systematically studied. We therefore examined 8 hemispheric PNETs and 35 medulloblastomas with 17p restriction fragment length polymorphism (RFLP) and microsatellite markers. We also examined the TP53 tumor suppressor gene by a combined polymerase chain reaction-denaturing gradient gel (PCR-DGGE) technique. Our results showed that all of the 17p markers tested were preserved in all of the supratentorial PNET specimens. In contrast, loss of distal chromosome arm 17p was detected in 37% of the medulloblastomas. Analysis of the TP53 gene showed 2 mutations in the medulloblastomas and no mutations in the supratentorial tumors. These results show that the most common molecular genetic abnormality in infratentorial PNETS is absent in their supratentorial counterparts and suggests that alternative pathways and genetic events may be involved in their etiology.

Adolescent↗

[Neurofibromatosis and stenosis of the aqueduct of Sylvius. A magnetic resonance assessment].

Von Recklinghausen's neurofibromatosis is an autosomal dominant disease involving peripheral nerves and central nervous system. Obstructive hydrocephalus in this disease represents a common finding when it is due to the development of infratentorial neoplasm. Nevertheless, the occurrence of isolated nonneoplastic aqueductal stenosis in patients affected by neurofibromatosis has been described rarely. The authors report two cases of primary nontumoral aqueductal stenosis associated with Von Recklinghausen's disease who were diagnosed by CT scan and MRI. The pathogenesis of aqueductal narrowing in neurofibromatosis is discussed.

Adult↗

Detection and localization of occult lesions with brainstem auditory responses.

Seven vertex-positive potentials--the brainstem auditory response--can be recorded from the human scalp within 10 milliseconds of an appropriate acoustic stimulus. The first of these potentials is generated in the acoustic nerve, the third in the pons, and the fifth in the midbrain. Measurement of the relative latencies and amplitudes of these potentials allowed detection of subclinical lesions in 37 (53 percent) of 70 patients with suspected multiple sclerosis who had no signs or symptoms of brainstem involvement by the disease. Abnormalities in the brainstem auditory response provided the first evidence of the pressence of multiple lesions in 14 (35 percent) of 40 patients with suspected multiple sclerosis who had clinical evidence of only a single spinal or cerebral lesion. Response abnormalities also suggested the presence of tumors of the posterior fossa in three patients with nonspecific symptoms and normal neurologic examinations, the test indicated the need for contrast studies, which then led to the correct diagnosis of infratentorial neoplasm.

Acoustic Stimulation↗

Intramedullary spinal cavernous malformation following spinal irradiation. Case report and review of the literature.

There is a growing body of evidence in the literature suggesting that cavernous malformations of the central nervous system may develop after neuraxis irradiation. The authors discuss the case of a 17-year-old man who presented with progressive back pain and myelopathy 13 years after undergoing craniospinal irradiation for a posterior fossa medulloblastoma. Spinal magnetic resonance (MR) imaging, performed at the time of his initial presentation with a medulloblastoma, demonstrated no evidence of a malformation. Imaging studies and evaluation of cerebrospinal fluid revealed no evidence of recurrence or dissemination. Spinal MR imaging demonstrated an extensive lesion in the thoracic spine with an associated syrinx suggestive of a cavernous malformation. A thoracic laminectomy was performed and the malformation was successfully resected. Pathological examination confirmed the diagnosis. The patient did well after surgery and was ambulating without assistance 6 weeks later. To the best of the authors' knowledge, this is the second reported case in the literature and the first in the young adult age group suggesting the de novo development of cavernous malformations in the spinal cord after radiotherapy. An increased awareness of these lesions and close follow-up examination are recommended in this setting.

Adolescent↗

[Supratentorial hemangioblastoma].

The authors report the case of an isolated supratentorial hemangioblastoma occurring in a woman operated on for a cerebellar hemangioblastoma twenty years before. The data furnished by immunohistochemical technics don't seem to be deciding and don't work out the problem of hemangioblastoma histogenesis.

Carotid Arteries↗

[Severe pulmonary complications following venous air embolism in neurosurgical operations in sitting position--2 case reports].

The occurrence of air embolism during neurosurgical operations in sitting position is described in two cases. Besides the Doppler ultrasound evidence, relevant effects on the cardiopulmonary situation during surgery were observed, which in one case forced an early end of the operation. Postoperative management in both cases was complicated by a pulmonary oedema. In severe intraoperative cardiopulmonary complications in connection with venous air embolism, the existence of pulmonary oedema should be assumed. Confirmation of the diagnosis and the correct therapy depend upon frequent postoperative chest X-rays.

Brain Neoplasms↗

Chromosomal imbalances in meningeal solitary fibrous tumors.

We present the results of a comparative genomic hybridization (CGH) analysis of three meningeal solitary fibrous tumors (SFT). One case showed loss of chromosome 3 and two tumors had deletions of the region 3p21-p26. Other chromosomal losses included 4p15, 8q22-q24, 10, 11q14-q25, 17q11- q23, 20, and 21 in one case each. In addition, there were gains of 18p11-p13 in one case, and 1p11-p36 and 20q11-q13 in another. To our knowledge, there are no previous CGH or cytogenetic data on meningeal SFT, and loss of material on chromosome 3 has not been described in SFT at other sites. Our findings are discussed in relation to published molecular genetic and cytogenetic data on meningioma and hemangiopericytoma, the two lesions with which meningeal SFT are most likely to be confused.

Adult↗