The birth of human stereotactic surgery.

Stereotactic surgery began with the Horsley-Clarke apparatus which has been used in animal research since 1908. In 1947, Spiegel and Wycis introduced stereotactic surgery in human patients. Their initial choice of target involved the extrapyramidal system, which Russell Meyers had recently performed with craniotomy and manual lesions that might alleviate symptoms of movement disorders, albeit with significant morbidity and mortality, a problem not seen with stereotactic surgery.

Use of a volumetric target for image-guided surgery.

A VIRTUAL REALITY system has been devised to superimpose a computer-generated rendering of a volumetric target to be surgically approached or resected on a real-time video image of the surgical field. A stereotactic frame is used to register the image from the video camera with the image of the target volume for accurate localization. The volumetric target is obtained from preoperative imaging studies and can be modified to adjust the intended line of resection or to avoid eloquent vascular or neural tissue.

Evolution of basal ganglia surgery for movement disorders.

In 1942, it was thought that basal ganglia surgery would cause permanent unconsciousness and significant impairment of motor control. By 1947, when human stereotactic surgery was introduced, the first target was the globus pallidus in a patient with chorea. What happened during those 5 years to set the stage for stereotactic surgery? During the last half of the 19th century, it was first noted that motor disorders were often accompanied by atrophy of various parts of the basal ganglia, and when histopathology became part of necropsy, that relationship between movement disorders and the basal ganglia was strengthened.

Evolution of neuromodulation.

Neuromodulation, as defined as the use of electrical stimulation by implanted stimulators to treat various neurological conditions, has developed gradually from long experience with electrical stimulation of the nervous system. Indications are still evolving, and the field is advancing at an ever increasing rate.