Sudden death due to a central neurocytoma.

The central neurocytoma is a common, usually intraventricular tumor with bland histologic features. We report a case of a 51-year-old man who died suddenly. At autopsy, a neurocytoma with acute hemorrhage filled the anterior left lateral ventricle. The tumor matrix and surrounding brain tissue contained accumulations of hemosiderin. Previously, 2 cases of central neurocytoma with associated hemorrhage have been reported. Hemorrhage appears to be a serious complication associated with these neoplasms.

A syngeneic mouse glioma model for study of glioblastoma therapy.

Animal models of human tumors serve a vital role in the development and testing of new anticancer therapies. Since the immune system is likely to play an essential role in tumor eradication, there is a particular need for modeling human disease in immunocompetent hosts. Few models of glioma have been developed in immunocompetent mice that are commercially available and none of these tumors have histological and antigenic characteristics of human gliomas. We have used a cell line, 4C8, derived from a spontaneous glioma-like tumor that arose in a transgenic mouse to develop a new glioma model. The intracranial injection of 4C8 cells into immunocompetent syngeneic B6D2F1 mice resulted in tumors that were densely cellular, developed a pseudopallisading pattern of necrosis, and expressed GFAP; all important features of human malignant gliomas. The average neurological endpoint was 51 days after intracranial injection. The 4C8 cells also grew rapidly in the flank, retaining histologic features seen in intracranial tumors. Flank tumors reached an average volume of 100 mm3, a volume ideal for therapy testing, by 34 days postinjection. These results suggest that the 4C8 mouse glioma model is an excellent system in which to test new antiglioma therapies for use in humans.

Normal appearance of arachnoid granulations on contrast-enhanced CT and MR of the brain: differentiation from dural sinus disease.

PURPOSE: To determine the imaging appearance and frequency with which arachnoid granulations are seen on contrast-enhanced CT and MR studies of the brain. METHODS: We retrospectively reviewed 573 contrast-enhanced CT scans and 100 contrast-enhanced MR studies of the brain for the presence of discrete filling defects within the venous sinuses. An anatomic study of the dural sinuses of 29 cadavers was performed, and the location, appearance, and histologic findings of focal protrusions into the dural sinus lumen (arachnoid granulations) were assessed and compared with the imaging findings. RESULTS: Discrete filling defects within the dural sinuses were found on 138 (24%) of the contrast-enhanced CT examinations. A total of 168 defects were found, the majority (92%) within the transverse sinuses. One third were isodense and two thirds were hypodense relative to brain parenchyma. Patients with filling defects were older than patients without filling defects (mean age, 46 years versus 40 years). Discrete intrasinus signal foci were noted on 13 (13%) of the contrast-enhanced MR studies. The foci followed the same distribution as the filling defects seen on CT scans and were isointense to hypointense on T1-weighted images, variable in signal on balanced images, and hyperintense on T2-weighted images. Transverse sinus arachnoid granulations were noted adjacent to venous entrance sites in 62% and 85% of the CT and MR examinations, respectively. Arachnoid granulations were found in 19 (66%) of the cadaveric specimens, in a similar distribution as that seen on the imaging studies. CONCLUSION: Discrete filling defects, consistent with arachnoid granulations, may be seen in the dural sinuses on 24% of contrast-enhanced CT scans and on 13% of MR studies. They are focal, well-defined, and typically located within the lateral transverse sinuses adjacent to venous entrance sites. They should not be mistaken for sinus thrombosis or intrasinus tumor, but recognized as normal structures.

Evidence of meningioma infiltration into cranial nerves: clinical implications for cavernous sinus meningiomas.

Anatomical and biological studies of cavernous sinus meningiomas help us understand the biological heterogeneity of these tumors. The question of whether cavernous sinus meningiomas infiltrate cranial nerves is clinically important because of the effect on treatment planning. In the authors' experience of treating 36 patients with cavernous sinus meningiomas, tumor invasion into a cranial nerve was documented in two patients in whom a cranial nerve was resected during the cavernous sinus dissection. In both patients, histological examination using hematoxylin and eosin and bodian stains showed infiltration of the cranial nerves by a benign meningioma which, to the best of the authors' knowledge, is a condition previously unreported. This histological finding of meningioma invasion into a cranial nerve demonstrates the biological heterogeneity of cavernous sinus meningiomas and raises concern about the invasive character of meningioma. Because not all tumor cells can be identified radiologically or by direct visualization at surgery, occult tumor infiltration predisposes a patient to recurrence despite the best neurosurgical efforts. Evidence of cranial nerve infiltration by meningioma suggests that, in some circumstances, cavernous sinus dissection in the hope of total removal of a meningioma may be futile and, in the long term, may provide no advantage over treatment options with lower morbidity.

Morphologic variations of the external arcuate nucleus in infants dying of SIDS: a preliminary report.

The external arcuate nucleus (EAN), located in the ventral medulla, is studied in 24 infants dying of sudden infant death syndrome (SIDS) and 15 age-matched controls to identify differences in morphology in this region, thought to be involved in respiratory regulation. Significant differences are noted in EAN neuronal density, percentage of back-to-back neurons and volume of the EAN relative to the adjacent pyramids. These changes may be useful in evaluating sudden infant death.

Lipofibromatous hamartoma of the median nerve: case report with magnetic resonance imaging correlation.

The authors report a case of lipofibromatous hamartoma of the median nerve in a patient who presented with symptoms of carpal tunnel syndrome. The diagnosis was made by magnetic resonance imaging and confirmed by intraoperative findings and histological diagnosis; distinctive magnetic resonance imaging features of this entity are described. In this patient, surgery was limited to biopsy to confirm the diagnosis and external neural decompression, which helped to stop the progression of the symptoms. In their review of the literature, the authors found four types of lipomatous masses in the extremities affecting the function of peripheral nerves, commonly the median nerve. Treatment and the extent of surgery differ for each patient, based on the anatomical findings and extent of neurological deficit. The etiology, pathogenesis, differential diagnosis, and surgical management of lipofibromatous hamartoma are described.

Lipoma of the cerebral cortex: case report.

The first clinically diagnosed and successfully operated case of a symptomatic lipoma involving the cerebral cortex is reported. The patient presented with severe headaches and recurring focal seizures with secondary generalization. Computer tomography scan and magnetic resonance imaging suggested a left frontoparietal lipoma. After undergoing a craniotomy and tumor excision, the patient has shown resolution of headaches and seizures at 1-year follow-up. Lipomas of the cerebral cortex should be excised if symptomatic and accessible.

Sudden death due to lymphoplasmacytic hypophysitis.

We report the case of a 37-year-old mentally retarded woman who died suddenly with premortem clinical signs of diabetes insipidus. At autopsy, her pituitary was infiltrated and destroyed by a lymphoplasmacytic infiltrate, affecting the posterior pituitary more severely than the anterior pituitary. Vitreous electrolytes showed a pattern of hypertonic dehydration, compatible with diabetes insipidus.

Oligodendroglial gliomatosis cerebri.

A 34-year-old man presented with progressive neurologic deterioration though clinically to be multiple sclerosis. At autopsy, the cerebral white matter, deep gray matter, and brain stem were diffusely infiltrated with cells characteristic of oligodendrocytes. Gliomatosis cerebri consisting predominantly of oligodendroglia is rare.

Cardiac laceration and pericardial tamponade due to cardiopulmonary resuscitation after myocardial infarction.

Complications of cardiopulmonary resuscitation (CPR), such as rib fractures and pneumothorax, are not uncommon. The authors report the case of a 69-year-old woman who underwent surgery for a perforated duodenal ulcer. Eighteen hours postoperatively she sustained a cardiac arrest; vigorous resuscitation efforts, using advanced cardiac life-support procedures, failed. At autopsy, she had 350 mL of fresh blood in her pericardial sac, which had caused cardiac tamponade. Three ribs were fractured at the left sternal border. Directly underneath the fractured ribs were a 0.4-cm laceration of the pericardium and an accompanying 0.7-cm laceration of the left ventricle. There was an acute thrombus in the left anterior descending artery. Microscopic examination of the heart showed acute infarction of the left ventricle in the vicinity of the laceration. This case demonstrates that vigorous CPR performed on an acutely infarcted heart can result in lethal cardiac laceration and tamponade.