Yoshihiro Takebe

Effects of a Transfusion with a Blood Substitute (Fluosol-DA, 20%) on Cerebral Circulation in the Monkey

Local cerebral blood flow (lCBF) and electroencephalogram were monitored in six monkeys after a transfusion using a perfluorochemical suspension (Fluosol-DA, 20%) that has been manufactured as a blood substitute and is known to be synthetic, biologically inert, and nontoxic and to have a high capacity for carrying oxygen. The animals were mechanically ventilated, and blood gases were maintained at physiological levels. Fluosol-DA, 20% was administered either by an exchange transfusion of 20 ml/kg or by an infusion of 8 ml/kg followed by an exchange transfusion of 12 ml/kg. lCBF was measured using the hydrogen clearance technique. An equation was proposed to estimate the tissue-blood partition coefficient of hydrogen; this coefficient is considered to be dependent upon the amount of perfluorochemicals in the blood and was used to calculate lCBF. Systemic blood pressure, pulse rate, central venous pressure, electroencephalogram, and gas analysis of the blood from the femoral artery, the femoral vein, and the superior sagittal sinus showed little change throughout the experiment. lCBF was increased by 12% (p less than 0.005) after the infusion of Fluosol-DA, 20% of 8 ml/kg and by 31% (p less than 0.02) after the exchange transfusion. Hyperventilation reduced lCBF significantly (p less than 0.005), which implies that the reactivity of the cerebral blood vessels to hypocarbia was not impaired by the administration of FLuosol-DA, 20%. Both the results of this study and the physical properties of Fluosol-DA, 20% suggest that this blood substitute can safely be used for normal human brains and that it might also be effective for ischemic brains.

Neuroradiological aspects of suprasellar germinoma

SummaryThe plain skull roentgenography, angiography, air encephalography or positive contrast medium ventriculography and computed tomography (CT) of twelve cases of suprasellar germinoma were reviewed. In over half of the cases, plain skull roentgenography and angiography showed some abnormalities suggesting a suprasellar mass. CT was found to be the most appropriate for routine examination. And air encephalography or positive contrast medium ventriculography offered decisive information.

Adrenal Medulla Transplantation into the Putamen in Parkinson's Disease

Autologous adrenal medulla was transplanted into the putamen of a patient with severe Parkinsons disease. After the operation, the patients akinesia and rigidity decreased and the duration of action of L-dopa treatment was prolonged. The effect lasted for only 6 months, however, following which the patients condition gradually began to deteriorate again, returning to the preoperative state by 12 months after surgery. This paper discusses possible reasons why the effect was only temporary.

STA-MCA anastomosis in patients with skull base tumours involving the internal carotid artery—Haemodynamic assessment by ultrasonic Doppler flowmeter

SummaryThe role of superficial temporal artery -middle cerebral artery (STA-MCA) anastomosis was investigated with an ultrasonic Doppler flowmeter in 3 patients with sphenoid ridge meningiomas and one with a parasellar malignant teratoma, all of which involved the intracranial internal carotid artery. The intraoperative Doppler flow study revealed a remarkable increase in flow volume of the STA after trial occlusion of the middle cerebral artery in one case and permanent occlusion in two cases. These results substantiate the effectiveness of STA-MCA anastomosis. We also discuss surgical and other contrivances for obtaining sufficient blood supply from this bypass to prevent cerebral ischaemia in the acute phase after elective or accidental occlusion of a major cerebral artery. This is the first report of STA-MCA anastomosis in cases with brain tumour.

Experimental Study on Quantitative Flow Measurement by a Doppler Flowmeter with a Sound-spectrograph

A bidirectional ultrasonic Doppler flowmeter equipped with a sound-spectrographic analyzer has enabled us to determine blood-flow direction and to obtain useful information from the flow pattern in assessing the cerebral blood flow transcutaneously or intraoperatively. Using a regulated flow system produced in a dog, we performed an experimental study in order to establish the optimal mode for its use and to study the reliability in the quantitative cerebral blood-flow measurements. Although we could not measure the absolute blood-flow volume directly with this apparatus, we were able to obtain useful, quantitative information on blood flow and flow pattern by placing the ultrasonic probe in an appropriate position with respect to a blood vessel.