Use of the Horsley-Clarke Stereotactic Frame in Humans

It is well known that the Horsley-Clarke frame (HCF) was developed and engineered by the British physicians Robert Henry Clarke and Victor Horsley in 1906 for use in animals. It is less appreciated that the HCF was also used by the Frederic Gibbs group in 1947 for studies of human epileptics. Subcortical depth electrodes were placed using the relationship between external landmarks and intracranial structures and confirmed by pneumoencephalography. Events leading to the development of the HCF and its subsequent use in humans for depth recordings, and lesion production in the treatment of epilepsy, movement disorders, and psychosurgery are discussed.