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Clinical manifestations, findings, management and outcome of a series of 177 cases with tumours of the limbic and paralimbic systems are presented. There was no operative mortality. Postoperatively 95% of them had no or only minor neurological deficits. Most of them were able to resume work. Pre-operatively 77% of the patients had epilepsy, but 84% became seizure-free after tumour removal. All 77 cases with malignant tumours died within 1-5 years. In the past many neurosurgeons were reluctant to attempt complete tumour removal in these areas. This series demonstrates the efficacy of highly skilled microneurosurgery.

The clinical features, perioperative course, and postoperative outcomes of 144 patients who underwent microsurgical resection of craniopharyngioma were reviewed. Overall, 90% of the tumors were completely resected and 7% recurred. Evaluation of those patients who underwent primary resection revealed much better results. The operative techniques and approaches are reviewed in detail. The results of this series suggest that primary total removal of craniopharyngiomas yields the best long-term outcome for the patient. Experience has shown that the larger the tumor the greater will be the damage, both preoperatively and intraoperatively, to vital intracranial structures. Consequently, early diagnosis, at a stage when the tumor is still small, improves the chances of accomplishing complete removal and of achieving good operative results. The early diagnosis of craniopharyngioma, before it can produce devastating neurological defects, continues to be the principal goal of our medical and pediatric colleagues.

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An anatomical study of the vascularization of the hippocampus was performed on 30 hemispheres. There were a total of 140 arteries supplying the hippocampi, for an average of 4.7 arteries per hemisphere (range three to seven arteries). Based on the origin and caliber of the arteries supplying the hippocampus, the hemispheres were divided into five groups: A) in 57% of the hemispheres studied, the origin was mixed and included the anterior choroidal artery (AChA), the main trunk of the posterior cerebral artery (PCA), and the inferior temporal, lateral posterior choroidal, and splenial branches of the PCA; B) in 27%, all of the inferior temporal branches of the PCA predominantly supplied the hippocampus; C) in 10%, the anterior inferior temporal branch of the PCA was the predominant supplier: D) in 3%, the hippocampus was predominantly supplied by arteries originating from the main trunk of the PCA (Uchimura artery); and E) in 3%, the AChA gave origin to the hippocampal vessel. It was found as a result of this study that the PCA directly and by its branches contributes much more to the blood supply of the hippocampal formation than the AChA. The uncal sulcus was found to be an important anastomotic site between the hippocampal branches of the AChA and the hippocampal branches of the PCA. In 26.6% of hemispheres, one of the hippocampal arteries arose from the lateral posterior choroidal artery. The splenial artery made a loop close to the extraventricular part of the hippocampal tail and gave off multiple vessels to this structure in 36.6% of hemispheres. The finding that the AChA passes through the choroid fissure as a trunk and its later division into the lateral plexal and medial perforating branches within the choroid plexus may be of surgical significance.

The surgical outcome in terms of seizures was rewarding in the majority of patients, particularly in those who exhibited the following irregularities on preoperative investigations: regular local dysfunctions on electroencephalography, dysmorphic changes in the mesiobasal temporal parenchyma on MR imaging studies, and hypometabolism in the anterior third of the temporal lobe on PET studies.

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SUMMARY To study the possible role of catecholamines in platelet activation, platelet aggregation stimulated by AI?P, collagen, arachidonic acid and l-epinephrine, thromboxane B2 (TXB2) formation and plasma levels of catecholamines and renin were studied in healthy men both before and after 6 days of propranolol treatment (40 mg three times daily) under control conditions and during sympathoadrenergic stimulation by physical exercise (200 W) or smoking. Exercise markedly increased plasma norepinephrine from 128 ± 28 to 998 ± 418 pg/mI (± SD), and plasma renin activity from 1.0 ± 0.5 to 4.2 ± 1.8 ng Al/ ml-hour. Smoking predominantly increased plasma epinephrine, from 47 ± 25 to 154 ± 76 pg/ml. Propranolol did not consistently influence these variables, but blunted the circulatory response to exercise and smoking. Despite the marked increases of plasma catecholamines after both stimuli with and without blockade, platelet aggregation stimulated by ADP, l-epinephrine, collagen and arachidonic acid and associated TXB2 formation were not enhanced. Moreover, as already suggested by a trend toward reduced aggregability in these settings, plasma norepinephrine levels in the same range (745 ± 368 pg/ml) due to infusion (5 ,tg/min) significantly reduced platelet aggregation with low-dose collagen (0.25-0.75 ,ug/ml), 1-epinephrine (0.2-1.0 ,uM) and ADP (0.5-1.5 ,uM). These data do not support a role of endogenous catecholamines in initiating platelet activation and TXB2 formation.SMOKING, a well-documented cardiovascular risk factor, and physical effort, which may precipitate myocardial infarction in patients with preexisting coronary artery disease, stimulate catecholamine release.`6 Abnormally reactive platelets may play a role in the development of coronary heart disease and acute myocardial infarction.7 I Several studies have suggested an association between physical stress and platelet activation in coronary artery disease.9 '4 After physical exercise'I 12 and pacing-induced tachycardia in patients with coronary artery disease, 13. 4 Six healthy male volunteers, mean age 30 + 4 years (± SD), who had not taken any medication for 3 weeks were studied after an overnight fast both before and after I week of treatment with propranolol, 40 mg three times daily. Data were assessed after 45 minutes of supine rest at 8 a.m. (control), after treadmill exercise (4 minutes at 100 W and 4 minutes at 200 W), 2 hours later after smoking of two cigarettes (1.6 mg of nicotine each) and, in a second experimental setting, before and after a 15-minute norepinephrine infusion (5 Ag/min). Blood pressure was recorded by sphygmomanometry, heart rate by ECG, and blood for laboratory studies was drawn from the antecubital vein in a carefully standardized manner.Platelet Aggregation and Thromboxane Formation