Autonomic and somatomotor responses to electrical stimulation of the posterior hypothalamus are reported in 51 patients with pathologically aggressive behavior. The stimulated area causing rise in blood pressure, tachycardia, and maximal pupillary dilatation lies in the posteromedial hypothalamus, more than 1 mm and less than 5 mm lateral to the lateral wall of the third ventricle, occupying a triangle formed by the midpoint of the intercommissural line, the rostral end of the aqueduct, and the anterior border of the mammillary body. Electrical stimulation of this (ergotropic) triangle resulted in desyncbronization of the electroencephalogram (EEG) with hippocampal theta waves, or diffuse irregular delta waves of high voltage.Cases with violent behavior showed higher plasma levels of non-esterified fatty acids (NEFA) in the fasting stage; these were markedly elevated by electrical stimulation of the ergotropic triangle.Points in the ergotropic triangle where signs of sympathetic discharge were most marked were electrocauterized bilaterally. This procedure produced marked calming effects (95% of the cases) during the follow-up period of more than 2 years. Postoperatively there was a tendency to a decrease in sympathicotonia or an increase in parasympathicotonia. The follow-up plasma level of NEFA was found to have decreased to approximately the normal value.Y. Neurosurg. / Volume 33 / December, 1970 69]

No abstract

An implantable device for measurement of cerebrospinal fluid (CSF) flow in a ventriculoperitoneal shunt tube has been developed. The unit is energized by an extracorporeal high-frequency generator (200 KHz), and electrolysis creates bubbles in the shunt tube. Velocity of bubble flow is detected by a pair of ultrasonic Doppler probes placed a certain distance apart on the skin surface and in parallel with the implanted tube. The CSF flow rate is calculated taking into account velocity and tube diameter, and is expressed in ml/min. The unit consists of a coil with a capacitor, a silicon diode to rectify the high frequency, and a Zener diode to regulate maximum output voltage of 20 V. The output is fed to a pair of platinum electrodes placed inside the unit's tunnel through which the CSF flows. These components are molded in epoxy resin and coated with medical-grade silicone rubber. In animal experiments, CSF flow rates ranging from 0.033 to 1.0 ml/min could be measured by this flowmeter. Clinically, CSF flow has been measured to date in several cases. In two cases of communicating hydrocephalus occurring after the onset of cerebrovascular disease, and in which the CSF flow was continuously monitored for 24 hours, the flow rate ranged between 0.05 and 0.78 ml/min. The CSF flow rate fluctuates in a 24-hour period, increasing in the morning, especially between 12 midnight and 6 a.m., which suggests a circadian rhythm.

No abstract

Renal dipeptidase purified from swine kidney hydrolyzed N -formimidoyl thienamycin, carpetimycins A and B, and Sch29482, but not azthreonam, penicillin G, or cephaloridine.