passages.id: split_4_test_1767_passage
passages.type: progene_text
passages.text: Between January 1998 and June 1999 these 17 consecutive patients ( age 48 - 68 years ; illness duration 8 - 27 years ) underwent bilateral stereotactically guided implantation of electrodes into the subthalamic nucleus in the Department of Neurosurgery of the Istituto Nazionale Neurologico " C. Besta. "