Guillain-Barré syndrome and optic neuropathy in acute leukemia.

We report the unique case of an 18-year-old man with acute myelomonoblastic leukemia in whom Guillain-Barré syndrome and optic neuropathy developed as a part of a clinical presentation.

Multiple neuroepithelial (colloid) cysts: association with other congenital anomalies.

A 4-year-old boy had three neuroepithelial cysts, one in the third ventricle and two in the supratentorial subarachnoid space, and also had stenosis of the cerebral aqueduct, obstructive internal hydrocephalus, frontoethmoidal meningoencephalocele, and right microphthalmia. The occurence of these combined lesions supports the congenitially derived nature of the cysts. The cysts originated from neuroepithelium including ectopic ependyma-lined structures. The exception may be those cysts arising in or near the floor of the third ventricle; these cysts could be derived from the cleft of Rathke's pouch, an endodermal derivative. Folding of the neuroepithelium in contact with mesenchyma or neuroglial tissue is proposed as the mode of formation of most "colloid" cysts. Review of the literature as well as our experience indicates that neuroepithelial cysts are widely distributed throughout the central nervous system.

Effect of serotonin depletion on nitric oxide induced cerebrovascular nociceptive response.

The study was conducted to investigate the effect of serotonin depletion on nitric oxide-induced meningeal vascular response and cerebrovascular nociception. Nitroglycerin was infused i.v. to control and serotonin-depleted rats. Pial circulation was monitored by intravital fluorescent videomicroscopy and Fos immunoreactivity trigeminal nucleus caudalis neurons was used as an indicator for the cerebrovascular nociception. The results showed that the degree of nitric oxide-induced pial microvascular dilatation was significantly greater in the serotonin-depleted group than the control. The number of nitric oxide-evoked Fos-immunoreactive cells between the two groups remained comparable. The results suggest that though depletion of serotonin can facilitate the vascular response to nitric oxide it does not alter the nitric oxide-induced craniovascular nociceptive response.

Extramedullary subdural meningioma after trauma.

A 61-year-old man had an extramedullary subdural meningioma occurring close to the site of an old vertebral traumatic fracture and spinal cord injury. The tumor was discovered 3 years after the spinal trauma. This finding supports the existence of a causal relationship between trauma and subsequent tumor development. A review of the literature disclosed only one other case of intraspinal meningioma after the traumatic fracture of the spine with spinal cord compression.

Genetic heterogeneity and progression in different areas within high-grade diffuse astrocytoma.

The primary objective of this study was to determine loss of heterozygosity (LOH) in various portions of 9 high-grade diffuse astrocytomas, 8 glioblastomas and 1 anaplastic astrocytoma. LOH was observed on chromosomes 9, 10, 17 and 19 in 8, 3, 4 and 2 cases, respectively. Genetic heterogeneity and a multistep process were identified in 4 glioblastomas explaining the diverse morphological characteristics, a common feature of diffuse astrocytomas. In 2, 2, 3 and 1 cases, the allele losses were found within part of grade IV astrocytomas but not grades II or II/III, on chromosomes 9, 10, 17 and 19, respectively. In one of these, while genetic heterogeneity was observed on chromosome 17 between the area of grade II and grade IV, 9pLOH was found within both areas and occurred on the same allele. The other 5 cases did not demonstrate genetic heterogeneity and the LOH was on the same allele, irrespective of grade, suggesting clonal origin. In conclusion, at the molecular level, the diverse morphological features of astrocytoma develops by a multistep mechanism of genetic alterations from one cell via low-grade and more malignant tumors towards glioblastoma.

Combined neurilemmoma and angioma. Tumor of ectomesenchyme and a source of bleeding.

Eight cases are described of intracranial and peripheral neoplasms composed of mixed neurilemmoma and hemangioma. It is proposed that ectomesenchyme can differentiate into neurilemmoma and angioma. The latter may be related to recently described angiogenetic factors, or to developmental factors as in rare cases of arterial angiomas. The angiomatous part may be common, but has often been overlooked. The presence of abnormal vessels, whether in kind or in number, helps explain various biological features of neurilemmoma. These vessels frequently bleed within the tumor, which results in the characteristic hemosiderin-laden macrophages. Bleeding may also occur into the cerebrospinal fluid (CSF) to create xanthochromia. The frequent increase in CSF protein in cases of neurilemmoma is attributed to transudation of serum from abnormal vessels. Less commonly, bleeding may be sufficient to cause subarachnoid hemorrhage. The dense collagen usually associated with these angiomas accounts for the relative infrequence of major hemorrhages.

A combined neurilemmoma and angioma of the parasellar region. Case report.

A combined neurilemmoma and angioma of the parasellar region is presented that clinically simulated a pituitary tumor. The lesion produced increased intracranial pressure and subarachnoid hemorrhage (SAH). This neoplasm is believed to have originated from the leptomeninges or the perivascular neural elements, or both. The angiomatous network within the tumor could have been the source of the SAH.

Solitary primary intracranial extracerebral glioma. Case report.

A case is presented of a solitary primary extracerebral mixed glioma occurring in the right suprasellar and parasellar region of a 49-year-old woman who had bilateral temporal hemianopsia for 3 months. At craniotomy, the well demarcated outline and extracerebral location of the tumor suggested that it was a meningioma. However, its gliomatous nature was confirmed by identification of glial fibrillary acidic protein (GFAP) in the tumor cells. Review of nine reported solitary primary intracranial extracerebral gliomas, including the present case, revealed that they tended to occur in the third to fifth decades of life, in patients with an average age of 42 1/2 years, and without sexual predilection. All were supratentorial with a tendency to be situated in the vicinity of the Sylvian fissure. Only the glioma in the present case was at the cranial base. They were diagnosed as three astrocytomas, two glioblastomas, two oligodendrogliomas, one astroblastoma, and one mixed glioma. A suggestion is made that all these gliomas arose primarily from heterotopic neuroglia in the leptomeninges.

Relation of age and cerebral ventricle size to central canal in man. Morphological analysis.

The central canal of the spinal cord in man with and without hydrocephalus was studied histologically. The lumen was patent in most patients in the first two decades of life. Cells lining the canal in the prenatal and newborn state and in the first decade of life were predominantly pseudostratified ciliated epithelium. In the second decade, the epithelium became simple columnar or cuboidal. The central canal closed in most cases after the age of 20 years, secondary to proliferation of ependymal cells and astrocytes. Mechanisms whereby the number of glial cells increase are considered. The canal was closed in all adults with normal ventricular size, and in 94% of persons with various degrees of hydrocephalus. In the remaining 6% of cases with hydrocephalus, the lining of the canal resembled that seen in the first two decades, and could have acted as a pathway of cerebrospinal fluid (CSF) absorption. Three cases of severe hydrocephalus in the first two decades of life were encountered; the central canal was patent in one, and occluded in two. Based on these data, the canal was not a significant pathway of CSF absorption in most instances of hydrocephalus and in persons with dilated ventricles who were older than 20 years of age.

Identification of a brain stone as calcified hemangioma: case report.

A 71-year-old woman with progressive hemiparesis had a large cerebral calculus (brain stone) removed from the temporal lobe. Her condition thereafter improved remarkably. The differential diagnosis and specific methods to determine the angiomatous nature of this almost acellular mass are discussed. Reticulin impregnation, elastic tissue stain, and electron microscopy were of greatest value.

Empty sella secondary to suprasellar colloid cyst of foregut (respiratory) origin. Case report.

An enlarged sella turcica was discovered in a 40-year-old man who had bitemporal headaches. A pneumoencephalograph revealed a third ventricular cyst, dilated lateral ventricles, and an empty sella. The colloid cyst was lined by foregut epithelium, probably originating in the respiratory tract, and dense connective tissue. This case is the first instance of an empty sella associated with a colloid cyst of the third ventricle. It is proposed that enlargement of the mass in the third ventricle caused increased pulsation pressure of the cerebrospinal fluid, and that in the presence of an incompetent diaphragma sellae the subarachnoid space expanded into the sella. The origin of third ventricle cysts is reconsidered. It is concluded that suprasellar colloid cysts may arise from endoderm, ectoderm, neuroepithelium, or a combination of these epithelia.

Acquired immunodeficiency syndrome associated with cerebral astrocytoma.

A 32-year-old homosexual man presented with headache and progressive right hemiparesis. CT scan revealed a heterogeneous ring-enhancing mass in the left parietooccipital lobe which proved to be astrocytoma. Clinicians should be aware of this new and unusual association of a cerebral glioma and acquired immune deficiency syndrome. Tissue examination is essential for proper diagnosis.

Ultrastructural parameters of limbic microvasculature in human psychomotor epilepsy.

Temporal lobe tissues from seven patients with drug refractory complex partial seizures were extensively examined using both light and electron microscopy in combination with certain computer techniques. Four of these cases had mesial sclerosis, whereas three cases had no demonstrable lesions in the hippocampus as determined by intermittent serial sections. Transverse sections of hippocampus were made and rapidly fixed in the operating theatre. Blocks were taken after orientation to a close-up photograph of the fixed unstained hippocampus. Cross sections of capillaries at a level where the nuclear outline was largest were photographed at low magnification in the electron microscope. Enlarged prints allowed the use of a computer-assisted planimetry and stereology system for determining capillary thickness, mean basal laminar thickness, mitochondrial incidence, and mitochondrial area of both endothelial and perithelial cells and numbers of light junctions occurring in the capillaries. Comparison of sclerotic tissues versus control showed a significant increase in laminar thickness of the sclerotic endothelia and perithelia. In endothelial cells of the disordered cortex there were fewer mitochondria than in controls; also these same endothelial cells had greater numbers of tight junctions. These changes are related to ongoing hippocampal neuron degeneration, dysregulations of the blood-brain barrier because of possible resistance to perfusion, and interference with transcapillary transport in relation to [K+] levels in neuronal milieu.

Light and electron microscopic observations of blood vessels in neurilemoma.

A study of 105 cases of neurilemoma disclosed frequent alterations of blood vessels, including hyalinized walls. Many vascular walls were formed by tumor cells. Two cases were analyzed by electron microscopy, and showed fenestrae, patent interendothelial gap junctions, and leakage of RBCs. The presence of erythrocytes in the gap junction and outside vessels is a factor acounting for xanthochromia of the CSF, and serum leakage for the frequent increase in CSF protein in cases of neurilemoma. Attenuation of endothelial cells increases the liability of vessels to bleed within the tumor. Massive bleeding may cause subarachnoid hemorrhage on rare occasions. Hyalinized vessels and dense collagen are features contributing to the relative infrequence of major hemorrhage. Evidence is presented that Schwann and perineural cells are similar.

Cerebellar medulloblastomas: a study of 35 cases with particular reference to cellular differentiation.

A series of 35 cerebellar medulloblastomas was studied using light microscopy and immunohistochemistry for localization of glial fibrillary acidic protein, an antigen specific for neuroglia. Most medulloblastomas occurred in children less than 15 years of age (77.1%), especially in the first decade of life (65.7%), with the peak incidence (40.0%) between 6 and 10 years. The rest were found in adults beyond 15 years of age (22.9%). The male to female ratio was 4:3. Ependymal differentiation was observed in 100% of medulloblastomas, astrocytic differentiation in 88.6%, oligodendroglial differentiation in 34.3%, glioblastomatous differentiation in 8.9%, and neuronal differentiation in 8.9%. These data suggest that medulloblastoma is a primitive (stem cell) neuroepithelial neoplasm with the capacity of differentiating along both neuroglial and neuronal directions. Excessive mucin production was encountered in one medulloblastoma. Leptomeningeal invasion occurred in 34.3% of medulloblastomas and endothelial hyperplasia in 28.6%. One medulloblastoma (2.9%) spread postoperatively to several bones.

Localized necrotizing arteritis of the central nervous system.

We describe a case of necrotizing arteritis of the brain in a 26-year-old man who presented as organic brain syndrome. The lesion has been confused clinically with acute encephalitis. At necropsy, no other abnormalities suggestive of systemic arteritis were found. Such CNS-restricted necrotizing arteritis of medium and small arteries in the absence of granuloma is extremely uncommon.

Primary chromoblastomycosis of the medulla oblongata: complication of heroin addiction.

A 20-year-old male heroin addict had a sudden onset of progressive medullary dysfunction and died within 12 days. Postmortem examination disclosed mycotic granulomas due to primary chromoblastomycosis strictly limited to the medulla oblongata and adjacent leptomeninges. Similar lesions were absent outside the central nervous system. Such pathologic lesions related to narcotic addiction have not been reported previously.

Magnetic resonance images of brain stem infarct in periarteritis nodosa.

A 35-year-old woman displayed unusual symptoms of progressive bulbar dysfunction. At necropsy, systemic necrotizing vasculitis and small pontine infarcts were demonstrated. The angiographic and magnetic resonance imaging findings are described. The latter investigation is a sensitive method for detecting such pontine lesions. To our knowledge, this case is the first report of magnetic resonance imaging findings of brain stem infarct in a patient with periarteritis nodosa.

Estrogen receptors in acoustic neurilemmomas.

Acoustic neurilemmomas are more frequent, larger, and more vascular in women, and such lesions have a rapidly progressive clinical course in pregnant women; these findings suggest that the growth of these neoplasms may bear a relationship to certain hormone levels. Tissues from 8 patients with acoustic neurilemmoma (3 men and 5 women) were studied by a new fluorescent steroid histochemical technique to detect the presence of estrogen receptors in or on neoplastic cells. Estrogen receptor protein has also been found in meningioma cells in women. Neurilemmoma of the acoustic nerve is the second neoplasm of the central nervous system in which such receptors have been demonstrated.

Ultrastructure of capillaries in acoustic neurilemmoma.

The microvasculature of normal acoustic nerve tissue and small intracanalicular and large extracanalicular neurilemmomas was analyzed by electron microscopy. The capillaries of normal acoustic nerve were nonfenestrated, but the microvasculature in nerve-sheath neoplasms was fenestrated. Hypertrophy and hyperplasia of endothelial cells were observed only in the small lesions. The proliferated and enlarge endothelial cells often partially occluded the vascular lumen and formed multichannel vascular lumina. Many fenestrae of capillaries were found in small neoplasms, but these were rarely identified in the large extracanalicular lesions. The gap junctions of endothelium in small nerve-sheath neoplasms were long, wavy, and convoluted, had no openings, and differed from those of large lesions in which the tight junctions were short, straight, and occasionally patent. Additionally, heavy vascularization and erythrocytes within basement membranes were observed only in large neurilemmomas. These ultrastructural features may constitute a basis for differences between large and small acoustic neurilemmomas noted in cerebrospinal fluid findings.