Introduction

Abstract

Stereotactic neurosurgery was born in the mind of Robert Clarke, who in the early twentieth century (1906)— when he was convalescing from pneumonia in Egypt (Carpenter and Whittier 1952)—“used his genius to apply a simple principle out of its usual context”, and gave the impetus to research into deep brain structures (Schurr and Merrington 1978). By that time chnical neurosurgery did not exist. Surgical neurology was performed by neurologists with some surgical training and consisted for a great deal of apphed neurophysiology. It was, in fact, the ultimum refugium for neurologists to alleviate otherwise intractable disorders. Medical history describes three operations in which a burrhole was performed after localization of its site with the help of an “encephalometer”. This instrument was constructed by Professor D. N. Zernov (Moscow 1892) and is the first apparatus based on mathematical principles that, after fixation on the skull, could be used for spatial orientation (Kandel and Schavinsky 1972). It was, however, employed mainly in surface topography for localization of the cranial sutures and cerebral sulci. Therefore it seems justified to state that the modern era of stereotaxy began in 1906 when Clarke and Horsley pubHshed work on a new method of brain research using a Cartesian tricoordinate system.