Choroid plexus and arterial pulsation of cerebrospinal fluid; demonstration of the choroid plexuses as a cerebrospinal fluid pump.

IT IS COMMON knowledge that the cerebrospinal fluid pulsates with each heart beat, but this phenomenon has received little detailed attention. This paper presents a study of the cerebrospinal fluid pulsation secondary to the arterial pulse. The site of transfer, magnitude, and possible clinical importance of this pressure pulse are demonstrated and considered. This problem was first extensively investigated by Antoni * in Sweden, who examined the cerebrospinal fluid pulse in many conditions, particularly spinal block. O'Connell, 9 in England, also seriously considered this problem. He pointed out that most methods for measuring the pulsations are inadequate because of the damping effect of the manometers generally in use. Turchetti, 14 in Italy, used a method of photographing the meniscus of an open-bore manometer to measure the pulsations. However, this did not avoid the displacement of CSF into an open-bore tube, which is one of the primary sources of the damping effect.