1. Twenty-six patients with major unipolar depression were rated clinically and regional cerebral blood flow (rCBF) determined prior to and after six months of treatment with 75-100 mg/day amitriptyline (n. 16) or 200 mg/day amineptine (n. 10). 2. rCBF was measured in 16 regions over each hemisphere by the Xenon 133 inhalation method and was computed as the initial slope index (ISI). The severity of depression was quantified by the Hamilton rating scale for depression. 3. Baseline rCBF values of depressed patients tended to be lower than those of normal subjects. Significant reductions were observed for all probes exploring the frontal region of the left hemisphere and for some probes exploring the frontal region of the right hemisphere. Chronic treatment with amitriptyline induced a significant increase in rCBF in the left frontal region. Similar results were obtained after treatment with amineptine. 4. Besides confirming frontal lobe dysfunction in depressed patients which is reversed by treatment with classic tricyclic antidepressants, the present results show that this dysfunction may also be reversed by treatment with dopaminergic drugs.

As part of a prospective study, the influence of several premorbid and environmental factors on the presence, extent and severity of cerebral vessel atherosclerosis was studied in 462 patients with clinical diagnosis of RIA who underwent cerebral angiography. The extent and severity of atherosclerosis of the cerebral vessels was quantified using extracranial and intracranial cerebrovascular scores (ECS, ICS) based on the number and severity of the lesions in 11 extracranial and 21 intracranial arterial segments. Results of univariate and multivariate analyses indicate that the presence of atherosclerotic changes of cerebral vessels, as shown by angiography, was strongly related with age in both sexes. The lesions were more frequent in males, in particular under age 55. Elevated cholesterol was associated with a higher incidence of atherosclerotic lesions. Smoking was associated with a higher incidence of extracranial lesions. Age, smoking and history of hypertension were the best predictors of the extent and severity of cerebral vessel atherosclerosis.

It is well established that cerebral blood flow (CBF) is low in patients with high hematocrit and is high in anemic patients. An inverse relationship between CBF and hematocrit has been found. Furthermore, if hematocrit is reduced, CBF increases. There is some debate as to whether these observations are due to viscosity or to oxygen carrying capacity of the blood. In order to further elucidate this problem, CBF, blood viscosity and hematocrit were measured in 4 patients with paraproteinemias before and after paraproteins had been removed by plasmapheresis without changes in hematocrit. After plasmapheresis, blood viscosity significantly decreases and CBF increases by a mean of 24.4 ml/100 g/min. Mean arterial blood pressure and hematocrit were not influenced by plasmapheresis. These results indicate that blood viscosity is an important factor in determining CBF. This does not exclude the role of oxygen transport as an associated factor, but it is evident that oxygen transport and blood viscosity are independent variables in the control of CBF.

A double-blind clinical trial was carried out involving 26 hospitalized, depressed patients who were randomized into two groups. Patients in each group received chlorimipramine (50 mg/day), combined with L-5-HTP (300 mg/day) in Group A, and with placebo in Group B. The trial lasted 28 days. Two Group B patients dropped out. All the patients were evaluated by HRSD each week, and by ZDSI and CGI at the beginning and end of treatment. Several statistical analyses of the mean HRSD scores of each item presenting initial positive response and of ZDSI scores for both reactive and endogenous depression were performed, using Student's t-test. To evaluate the efficacy of the chlorimipramine +L-5-HTP combination versus control therapy the Mann-Whitney test was applied to the reduction in HRSD scores, showing 0.05 significance. The results for both types of pathology were quantitatively and qualitatively more positive for Group A than for Group B. Cluster analysis of HRSD item scores alone and between this scale and ZDSI, according to Carrol's correlation method for the symptoms of the cluster (mood, anxiety and somatic symptoms), was carried out to confirm the above results.

A clinical and angiographic study was conducted in 360 patients with previous reversible ischemic attacks (RIAs) in order to verify the influence of hematocrit, hemoglobin and red cell count within the normal range in the clinical picture of cerebral infarction and its relationship with angiographic atherosclerosis. No significantly different distribution of the three parameters considered has been found according to the presence and the degree of atherosclerosis. On the contrary, our data have shown a significant correlation between levels of hematocrit, hemoglobin and red cell count and some clinical aspects of the RIA when angiographic atherosclerosis is present.

Two cases of histopathologically documented Creutzfeldt-Jakob disease were observed in the same area of the province of Siena in 1974–1975. The transmission of the disease was obtained through brain homogenates and lymphnodes in one of the two cases.

The effect of pentoxifylline on cerebral blood flow (CBF) was studied with the intravenous 133Xe clearance technique in eleven patients with chronic cerebrovascular disease. Pentoxifylline was administered orally at a dose of 1200 mg/day over a period of 30 days (eight patients) or by intravenous infusion of 100 ml saline containing 400 mg of the drug in 1 hour (three patients). CBF was measured before and after pharmacological treatment. CBF was found to be significantly increased by both acute and chronic administration of pentoxifylline.

On the basis of findings obtained by means of both traditional and modern tomographic techniques, Authors discuss changes of cerebral blood flow (CBF) and metabolism in acute cerebral ischemia and chronic cerebral circulatory insufficiency. Drug effects on cerebral circulation and metabolism are examined and experiences with pentoxifylline, substance provided with haemorheologic action, are reported.

Continuous carotid infusion of short-lived krypton-81m (t1/2 13 sec) yields an assessment of regional cerebral perfusion. This assessment can be obtained in three dimensions if activity is recorded with a rotating gamma camera and a computer to reconstruct krypton-81m distribution in tomographic sections. These showed several advantages over conventional views: (a) visualization of blood-flow distribution within brain structures (gray and white matter, basal ganglia); (b) more accurate location and evaluation of areas of relatively reduced or increased perfusion; (c) better definition of patterns of collateral circulation; (d) greater sensitivity and specificity in detecting and defining blood-flow changes during physiological activation studies. A limitation of the krypton-81m technique is its invasiveness. However, this study shows that the combination of new advances in radiochemistry with single-photon emission computed tomography may result in accessible methods for assessing, noninvasively and in three dimensions, the behavior of cerebral function in man.

In order to obtain functional images of brain perfusion, we exploited a new concept, which is to take advantage of the short half-life of a radioactive tracer. Under continuous intracarotid infusion of a solution of Kr-81m (T1/2 = 13 sec; produced from its parent, 4.6-hr Rb-81), this tracer will never reach equilibrium within the brain because of the rapid radioactive decay. Its distribution will therefore reflect regional arrival of the nuclide, indicating regional cerebral blood flow rather than volume. During continuous infusion of Kr-81m, perfusion images can be obtained by simply collecting counts with a gamma camera and recording on Polaroid film. The procedure is readily repeatable in order to get images in multiple veiws or to follow minute-by-minute changes of cerebral perfusion.