Search

A study of 130 patients having presented either a transient ischemic attack or a completed stroke, or admitted for an asymptomatic carotid stenosis, allowed the following investigations: CT-scan, doppler, angiography, measurement of the regional cerebral blood flow (rCBF) by the study of 133Xe clearance (Novocerebrograph (R)), and measurement of the regional cerebral blood volume (rCBV) made by gamma emission tomography after autotransfusion of 99m Tc-labeled erythrocytes with an Elscint Apex 415 ECT (R) camera. Our aim was to look in which case a rCBF and/or a rCBV interhemispheric asymmetry was observed, by comparing the previous hemodynamic parameters with clinical, CT-scan and angiographic data. Although a rCBF and/or a rCBV asymmetry appeared more often among patients presenting with infarction than among those of the asymptomatic category, this does not seem specific for any clinical grade. The same statement applies to the comparison between hemodynamic parameters and CT data. The arterial lesions were classified in 4 groups: no stenosis (12 cases), uni or bilateral moderate carotid stenosis (40 cases), unilateral severe carotid stenosis or occlusion (65 cases), bilateral carotid severe stenosis or occlusion (13 cases). We observed a rCBF asymmetry among some patients in the 4 groups, although this was more frequent among the two latter groups. Nevertheless no case of a rCBV asymmetry was observed in the 2 first groups. Such an asymmetry was present in 31 percent of the patients belonging to the two latter groups. In patients of the third group the asymmetry was always due to a relative increase of rCBV beyond the carotid lesion.(ABSTRACT TRUNCATED AT 250 WORDS)

A patient with a left parieto-occipital tumor presented generalized convulsions, and aphasia with alexia and agraphia. Diagnosis was confirmed by CT scan. Partial excision only was possible and was followed by radiotherapy. Histology showed the tumor to be composed of moderate and large sized cells with a granular PAS+ cytoplasm. Protoplasmic astrocytes were numerous at the periphery. Electron microscopy demonstrated typical features of Abrikossof's granular cell tumor: heterogeneous granulations constituted mainly of secondary lysosomes, autophagic vacuoles, multivesicular bodies, and rare angular bodies. The granular cells were interspersed with astrocytes, the feet of which were implanted on the capillary basal membrane. Immunoperoxidases assay of gliofibrillary protein acid demonstrated high levels in the intercellular prolongations, considered here to be astrocytic, but weak concentrations in the granular cells. This suggests uptake by the latter cells of adjacent astrocytic gliofibrillary protein acid, especially as the action of an anti-albumin serum on the tumor demonstrated that the granular cells can take up extracellular proteins by a passive mechanism. These findings stand against an astrocytic origin of the tumor. Comparison with other granular cell tumors, particularly pituicytomas, provides evidence of morphological unity, but cerebral granular cell tumors are rich in astrocytes, whereas these are absent in pituicytomas. The oncogenic unity of these tumors has not been established.

A patient presented with visual and tactile agnosia due to a spontaneous left occipito-temporal hematoma. Major memory and spatial orientation disorders were also noted, but language, gestures, auditory and olfactory perception, and interior visual imagerie were unaffected. A review of the literature since 1970 found 6 cases of an association of this type among 17 patients with visual agnosia. There appears to be no relationship between the presence of tactile agnosia and the global or partial character of the visual agnosia, the severity of memory disturbances, the presence of visuoverbal disconnection or visual imagery disorders. In contrast, these cases differed in that the lesions were more extensive and extended beyond the internal occipital regions: they were widespread in 3 cases and in the left internal occipital and parietal region in 1 case. In the patient reported in this paper there was a wide lesion of the posterior white matter of the left hemisphere.