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SUMMARY In 20 necropsies with 15 stenosed and 17 thrombotic occluded internal carotid arteries there were 46 cerebral infarcts larger than 1 cm diameter. Using portmortem arterfographic and pathological techniques the patterns of the neck and brain artery systems were correlated with the situation and extent of the brain infarcts.Massive Infarcts involving two major cerebral artery territories were associated with distal internal carotid artery occlusion and grossly ineffective cervical and circle of Willis anastomoses.Isolated middle cerebral artery territory infarcts were associated with internal carotid occlusion or stenosis and impairment of the circle of Willis anastomoses, perhaps with middle cerebral artery stenosis. The pattern of adequate size arteries determined if these infarcts were total, deep central, anterior, medium or posterior partial territory infarcts.Boundary zone infarcts were associated with internal carotid artery disease and limitation of anterior or posterior circle of Willis anastomoses. These limitations determined which boundary zones were affected.Isolated anterior cerebral artery territory infarcts were associated with bilateral internal carotid disease and an anterior cerebral artery stenosis or small caliber anterior communicating artery.Isolated posterior cerebral artery territory infarcts were associated with internal carotid disease and a direct impairment of the ipsilateral posterior cerebral artery capability.Stroke Vol 17, No 1, 1986 69THE FREQUENT ASSOCIATION OF STENOTIC and exclusive internal carotid artery (ICA) disease with cerebral infarction is well recognized. 1 " 5 Although some reports have related the nature, severity and extent of the vascular and of the ischemic lesions,^9 further clarification of these relationships is desirable. In this paper an analysis is made of the arterial patterns associated with the various brain infarcts in a group of necropsy cases with ICA stenosis or occlusion and large cerebral infarcts. In all cases the entire carotid, vertebral and cerebral artery systems were initially studied using a post-mortem arteriographic method 10 which readily demonstrates anastomatic pathways with adequate filling of arteries distal to occlusions. The arterial lumen is also fixed distended 1 ' so that the degree of lumen stenosis observed with the complementary pathological techniques is more related to that existing in vivo than that seen after the contraction of standard fixation methods. Small focal infarcts less than 1 cm are not considered in this report. Materials and MethodsIn a series of 91 patients with suspected cerebrovascular disease which were specially studied at necropsy, there were 72 with brain infarcts of which 20 were cases with severe stenoses or occlusions by thrombosis in the ICA and with cerebral infarcts larger than 1 cm in diameter. The other cases with embolic arterial occlusion or with small focal infarcts are not considered here. The 20 cases comprised 17 males and 3 females aged 41 to 86 with a mean age of 69.6 years. All sh...

Young adult rabbits have been given methyl mercury salts by subcutaneous injections or by gastric intubation. After 3 daily doses of 7.5 mg/kg by the 8th day moderate to severe ataxia developed, and after 4 doses, severe ataxia. Some of these latter animals might die. This species, therefore, seems to be about twice as sensitive to the neurotoxic properties of methyl mercury salts as the laboratory rat. With the light microscope extensive degenerative changes were seen in primary sensory ganglion cells, in both Purkinje and granule cells of the cerebellum, and in certain cells in several regions of the forebrain. The earliest changes became visible microscopically about the fourth day after commencing dosing, and reached a maximum of severity from the 7th to 10th day. The pattern of neuronal damage more closely resembled that found in the cat and in man than that seen in the rat. No evidence of changes vascular permeability was detected.

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Male and female rats were fed a commercial diet lacking pyridoxine. Using radiological and histological methods the growth of the long bones in the pyridoxine-deficient rats from 2 wk to 6 mth of age was compared with that in paired-fed and in paired-weight-gain control rats of the same age and sex given the same diet supplemented by daily injections of pyridoxine hydrochloride. Measurements of tibial bone length were significantly reduced in the deficient male rats but not females, possibly due to the reduced requirements for growth in the female. Thin epiphyseal plates were a feature of the limb radiographs in all the pyridoxine-deficient rats. Histologically the growing long-bone ends showed a diminished activity of endochondral ossification with thin epiphyseal cartilage and fewer shorter, broad and irregular bone trabeculae in the metaphyses of the deficient rats. These metaphyseal changes resemble those described in starvation.