A stereotaxic device for directing a puncturing tool toward a designated target within a patient. A tool guide is provided for directing the puncturing tool toward the target, and a positioning device for positioning the tool guide anywhere on a hemispherical surface from which to direct the puncturing...http://www.google.fr/patents/US5080662?utm_source=gb-gplus-shareBrevet US5080662 - Spinal stereotaxic device and method
