A Presentation of Pierre Janny

Abstract

At the first ICP-symposium in Hannover, Joe EVANS gave an introductory speech entitled “Historical Views of the Interest in Intracranial Pressure”. He finished his fascinating review by paying tribute to three investigators whose works signified a new epoch in the history of ICP — Eli GOLDENSOHN, Pierre JANNY, and Henry RYDER. These pioneers had two things in common — their main works were all published between 1950 and 1953, and they independently introduced modern electronic techniques for the continuous recording of the ICP. This innovation enabled them to make new and important observations. Goldensohn et al. (1) elucidated, by experimental investigations, the influence of CO₂ inhalation on the ICP and the relation between cerebral vasodilatation, cerebral blood volume and ICP. They also observed that the CSF pulse amplitude, measured by a strain gauge (i.e. approximately isovolumetric), was much larger than had been supposed on the basis of measurements with open fluid manometers. This phenomenon, already suggested by O’CONNEL (2) partly explained why previously the clinical importance of spontaneous rapid ICP variations had been principally overlooked.