Experimental CNS tumors in rats. Testing field for a computerized classification and tumor grading.

The purpose of this study was to verify the efficiency of a previously described method for the computerized histological diagnosis of experimental brain tumors (Kroh et al. 1988). 117 tumors (astrocytomas, glioblastomas, meningosarcomas, neurinomas, oligoastrocytomas and oligodendrogliomas), experimentally induced in rats, were studied. In every case the same 50 histological characteristics used for the elaboration of a computerized system for the diagnosis of experimental brain tumors in mice were analyzed. Our results demonstrate the efficiency of this diagnostic method for experimental brain tumors. Furthermore, the grade of malignancy of these tumors was also determined by using a previously described computer program.

Computer classification of experimental brain tumors in mice.

The purpose of this study was to develop a mathematical model which would be easy to use and which could provide an objective classification of experimental brain tumors. 250 brain tumors (glioblastomas, astrocytomas, astroblastomas, oligodendrogliomas, ependymomas, fibrosarcomas and giant cell sarcomas), induced in mice, were studied. In every case the same 50 histological characteristics were analyzed. For astroblastomas, oligodendrogliomas and ependymomas the diagnosis given by the neuropathologist and that given by the computer corresponded in 100% of the cases. However, some fibrosarcomas and giant cell sarcomas were not grouped in the same diagnostic category by the computer as that assigned by the neuropathologist. Thus an overall efficiency of 94.35% was obtained. This simple and efficient system of classification allows for further statistical analyses and makes it possible to correlate the results presented by different authors, thus providing for unity in all those works concerned with experimental neurooncology.

The fine structure of gliomatosis cerebri.

The ultrastructural features of five biopsies of gliomatosis cerebri (GC) are described. Four main types of tumour cells are seen: anaplastic astrocytes poor in organelles with a variable amount of glial microfilaments; atypical oligodendrocytes with scanty cytoplasm in which microtubules are present; intermediate forms with aboundant cytoplasm rich in organelles, with microtubules and microfilaments; and small cells with round nuclei and a very scanty rim of cytoplasm. In two cases several concentrically folded cytoplasmic lamellae of glial processes were arranged either around themselves or around the perikaryon of other cells. This ultrastructural study indicates that GC is a neoplastic process of small undifferentiated elements, transitional forms of astroglia (to oligodendroglia) and anaplastic cells of astrocytic origin in all stages of development.

Low doses of L-monosodium glutamate promote neuronal growth and differentiation in vitro.

Monosodium glutamate given at a concentration of 5 X 10(-6) M to whole-brain dissociated cultures of 18-day-old rats promotes neuronal growth. Neurons are larger due to an increased size of both cytoplasm and nucleus. Rough endoplasmic reticulum is more developed and mitochondria are more abundant. Synaptic vesicles are significantly increased in number with respect to control cultures. Synapses are more abundant and show a more differentiated morphology. These findings are interpreted as evidence for accelerated development secondary to the stimulatory effects of glutamate.

A model of semiautomatic type-specific diagnosis of brain tumours by computed tomography: mathematical fundaments and practical application.

Applying Escudero's formula to Bayes' theorem of conditional probabilities, we have developed a mathematical model to diagnose type-specific brain tumours with great accuracy. We have transformed a multidimensional system of n characteristics on computed tomography into a linear system, making this model very easy to use and, thus, accessible to the clinician and radiologist. We tested this model in 177 brain tumours. In 86% of the cases we obtained a type-specific correct diagnosis, achieving better results than those previously reported. Suggestions are given as to how to improve this method further.

Histopathological diagnosis of brain tumours with the help of a computer: mathematical fundaments and practical application.

With the help of a personal computer we have subjected 1684 tumours of the central and peripheral nervous systems to a discriminant analysis to test whether the different brain tumours can be classified. By ascribing a coefficient value which belongs to a linear function to the objective criteria for each tumour these can be ordered in groups, and a classification is then possible. This has been termed discriminant analysis. Fifty histological characteristics were the criteria taken into consideration for each tumour. By using Bayes' formula with a correction for binomial distribution we obtained a correct diagnosis in 98% of the cases studied. The differential diagnosis with its percentage of probabilities is given by the computer. The mathematical fundaments are given. The valuability and precision of this method are discussed.

The acute encephalitic phase of neurocysticercosis: computed tomographic manifestations.

Brain infestation by Cysticercus cellulosae, the larval form of Taenia solium, is a common disorder in Mexico and other Latin American countries, Asia, Africa, and some Eastern European countries. Recent immigration has caused an increase in the number of cases of neurocysticercosis in the United States. This work describes the acute encephalitic form of neurocysticercosis in 26 cases. The clinicopathologic and neuroradiologic manifestations are discussed with particular emphasis on the use of computed tomography as a main diagnosis modality which demonstrates multiple diffuse (85%) or localized (15%) enhancing nodules associated with severe edema.

Wernicke's encephalopathy. A case report with neurophysiologic and CT-scan studies.

A case of Wernicke's encephalopathy with ataxia, confusion, memory loss, partial seizures of complex behavior and hypothermia, subsequent to thiamine depletion due to chronic malnourishment and triggered by an episode of acute vomiting and diarrhea, is reported, Computerized tomography (CT-scan) depicted small bilateral lesions in areas adjacent to the walls of the third ventricle, common location of the lesions seen in autopsy material of Wernicke's encephalopathy. Early diagnosis and treatment with vitamin B complex supplemented with intensive mnemonic and cognitive therapy led to complete recovery in a ten day period.