When does a ganglion become a brain? Evolutionary origin of the central nervous system.

A brain, a neural structure located in the head, differs from a ganglion by the following characteristics: (1) a brain subserves the entire body, not just restricted segments; (2) it has functionally specialized parts; (3) it is bilobar; (4) commissures and neurons form the surface with axons in the central core; (5) interneurons are more numerous than primary motor or primary sensory neurons; and (6) multisynaptic rather than monosynaptic circuits predominate. A "cephalic ganglion" does not exist in any living animal and probably never occurred even in extinct ancestral species. It also is not a developmental stage in the ontogenesis of any vertebrate.

Combined angioma and glioma (angioglioma).

Ten patients in whom tissue proliferation akin to angioglioma occurred within the brain are described; seven of the lesions were supratentorial and three infratentorial. Only 31 accepted instances of such neoplasms have been found in the literature. The combined lesions usually become symptomatic in the second and third decades.

Essential hypertension: a sign in search of a disease.

The concept of disease is of cardinal importance in medical practice. The current definition has developed over more than 200 years. It includes a distinctive natural history and identifiable cellular changes.

Epidermoid tumors. Review of the literature.

Reports of epidermoid tumors from 1965 through 1986 were reviewed with emphasis on new and unusual findings. Clinical data considered were rapid onset, rare symptoms, size and rate of growth, and complications. Uncommon locations included multiple sites in one patient and the anterior fontanelle.

The brain of the planarian as the ancestor of the human brain.

The planarian is the simplest living animal having a body plan of bilateral symmetry and cephalization. The brain of these free-living flatworms is a bilobed structure with a cortex of nerve cells and a core of nerve fibres including some that decussate to form commissures. Special sensory input from chemoreceptors, photoreceptor cells of primitive eyes, and tactile receptors are integrated to provide motor responses of the entire body, and local reflexes.

Human tails and pseudotails.

A case of a tail in a 2-week-old infant is reported, and findings from a review of 33 previously reported cases of true tails and pseudotails are summarized. The true, or persistent, vestigial tail of humans arises from the most distal remnant of the embryonic tail. It contains adipose and connective tissue, central bundles of striated muscle, blood vessels, and nerves and is covered by skin.

Ischemia of the brain stem as a cause of sudden infant death syndrome.

Recent evidence indicates that the sudden infant death syndrome (SIDS) is related to abnormal control of respiration. Focal morphologic changes have not been noted. In a case of SIDS, ischemic degeneration was noted bilaterally in the medulla, particularly in the dorsal motor nucleus of the vagus nerve.

Hypothesis: Phylogenetic diseases of the nervous system.

A few human diseases may be viewed from a phylogenetic perspective. Some metabolic or degenerative diseases selectively affect recently evolved or exclusively mammalian structures of the brain and spare the older structures. Examples include Krabbe's leukodystrophy, olivopontocerebellar atrophy, Friedreich's ataxia, Pick's disease, and Leber's optic atrophy.

Mesenchymal differentiation in trigeminal neurilemmoma.

An unusual neurilemmoma of the trigeminal nerve in a 31-year-old woman is described. The neoplasm was roentgenographically calcified and contained various types of mesenchymal tissue, including a cavernous angioma, cartilage, bone, and adipose tissue. Angioma in combination with neurilemmoma occurs more frequently than other forms of mesenchymal tissue.

Familial gliomas: report of four families, with chromosome studies.

Four families having multiple family members with cerebral gliomas are presented. Genetic studies were done in some, but no chromosomal abnormalities were found in this group of patients or their families. The authors recommend that careful attention be given to the family history of all glioma patients and that more extensive genetic studies be done.

Differentiation of Medulloblastoma. Studies including immunohistochemical localization of glial fibrillary acidic protein.

A series of medulloblastomas was studied by light microscopy. The tumors were variable; astrocytic, ependymal, neuronal, and probable oligodendroglial differentiation was present. Features of glioblastoma multiforme occurred in one case.

Heterotopias of brain as a cause of infantile regurgitation.

A girl had persistent regurgitation of food from the first week of life until death at 19 weeks of age. Postmortem examination revealed widespread congenital anomalies including neuronal and neuroglial heterotopias of the thalamus and centrum semiovale on the left side, subependymal regions of both lateral and third ventricles, and both rostral medullary pyramids; and hypoplasia of the thalamus and cerebrum of the left side, and both lenticular nuclei. Moreover, the left lateral ventricle was moderately dilated, secondary to partial occlusion of the ipsilateral interventricular foramen.

Glioma of the acoustic nerve.

We report a case of astrocytoma of the acoustic nerve. Most gliomas arise from the brainstem, and seldom originate in the acoustic or other "true" cranial and spinal nerves. Clinical features of this rare acoustic tumor differ from those of brainstem gliomas, but are indistinguishable from typical acoustic neurilemoma.

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.

Subarachnoid spinal hemorrhage in a case of systemic lupus erythematosus.

A 50-year-old woman with an 18-year history of systemic lupus erythematosus (SLE) died after an exacerbation of the illness, characterized by deteriorating mentation and right hemiplegia. Necropsy revealed massive spinal subarachnoid hemorrhage resulting from aneurysmal dilation and rupture of the posterior spinal artery, which was involved by vasculitis. The left parietal lobe and internal capsule contained recent infarcts.

Disseminated intravascular coagulation following cranial trauma. Case report.

Cranial and spinal trauma resulted in disseminated intravascular coagulation (DIC) in a 78-year-old man, causing widespread bleeding and incoagulable blood. Traumatized brain tissue was found in the lumina of dural venous sinuses. The mechanisms of DIC are reviewed.

Intracanalicular neurilemmomas: clinicopathologic study.

Twenty-five patients with intracanalicular neurilemmonas were studied, the largest series yet reported. The tumors were most frequent in men by a ratio of 2:1, occurred more often on the left acoustic nerve, generally associated with long duration of symptoms and were equally distributed in the third to fifth decades, but the prevalence slightly increased in the sixth and seventh decades. A shorter length of illness occurred in younger persons as well as most patients with von Recklinghausen's disease.

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.

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.

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.

Phagocytic astrocytes and neurons in old encephalomalacia.

Cytoplasmic accumulation of hemosiderin was observed within astrocytes and neurons as well as in other phagocytes associated with old encephalomalacia. The first patient was 3 years old when she died with malnutrition and superimposed infection. A cortical infarct had been caused by an old thrombus in a small artery.