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George M. Austin, M.D.; Arnold S. J. Lee, A.B.; Francis C. Grant, M.D.
JAMA. 1956;161(2):147-148. doi:10.1001/jama.1956.62970020004006a.
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The development of subcortical surgery, with injections of chemical agents and radioisotopes into cystic brain tumors, and the treatment of intractable pain, involuntary movements, and tremor, by injecting specific nuclei, center around the satisfactory design and use of a human stereotaxic instrument. The idea of locating a needle tip in subcortical structures of the brains of cats and monkeys, with reference to a coordinate system, was first described by Horsley and Clarke.1 Their coordinate system dealt with rectangular coordinates using the external canal of the ear, the orbit, and the midline of the skull as fixation and reference points. This is the coordinate system that has been most frequently used by designers of similar instruments for the human brain. Leksell's2 instrument is an exception to this, in that it uses polar coordinates with an arc of a circle as the fixed frame. At present we have found description


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