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Controversy - the pros and cons Effect of trepanation on brain pulsations Mechanism and benficial effects of trepanation on cerebral circulation Trepanation across different cultural groups
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Brain Pulsations and their effect on healthBrain pulsations are vital for healthy body and mind. Brain pulsation is clearly visible in the infant child. The soft tissue on the top of the head known as the fontanel rises and falls with the beating heart. This expansion and contraction on the heartbeat does not threaten the infant's good health. However, within the first few months of life this tissue hardens into skull bone. The visual evidence that the heart beat still reaches into the brain vanishes before our eyes. Still the infant's good health is unaffected. Brain pulsation or intracranial pulse pressure has largely been ignored as a subject for investigation by the medical establishment in Western Europe and America. The primary investigators in modern times have been Russian. Most important amongst them is B.N. Klosovskii who is otherwise recognized internationally for his methods of studying blood circulation in the brain. In the mid 1950's he developed methods of tissue staining that allowed the arteries and the veins of the brain to be clearly distinguishable. The vascular bed was then for the first time clearly mapped. In the closing chapter of this text Klosovskii takes up the subject of brain pulsation. Using impedance electroplethysmography, an entirely different method than Klosovskii's direct observation through a "transparent window," they find that there is a "pulse wave" in the hermetically sealed skull. Their measurements indicate that this pulse is in the order of 1-2mm of water. Cardiac rhythm, pulse pressure, or pulsation is normally measured in mm. of Mercury (mm.Hg) not mm. of water. The difference in order of magnitude here is one to thirteen. They conclude, "in the hermetical cavity of the cranium, the pulse wave is transmitted indirectly from the arterial system into the veins and in doing so bypasses the capillary bed." The "pulse wave" that they have measure in the closed skull is in no way equivalent to the presence of "pulse pressure" that Klosovskii observes on the cerebral surface in the open skull. In a 1960 review titled Soviet Investigations in the Field of the Vascular Supply of the Brain, the noted American brain physiologist, Ernst Simonson, disputes those investigators using impedance plethysmography. He says, "The viewpoints are in need of confirmation, as it is rather difficult to imagine that alterations of intracerebral pressure of only 1 to 2 mm. water column can lead to blood being expressed from the cerebral veins, no matter how thin-walled these may be." Review of this information should provide researchers at the end of this century with the necessary focus to renew investigation of this topic using much improved bio-medical engineering. If you need more information, you are welcome to contact
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