Neural transplantation cannula and microinjector system: experimental and clinical experience - Technical note

The authors present a simple, reliable, and safe system for performing neur al transplantation in the human brain. The device consists of a transplanta tion cannula and microinjector system that has been specifically designed t o reduce implantation-related trauma and to maximize the number of graft de posits per injection. The system was evaluated first in an experimental rat model of Parkinson's disease (PD). Animals in which transplantation with t his system had been performed showed excellent graft survival with minimal trauma to the brain. Following this experimental stage, the cannula and mic roinjector system were used in eight patients with PD enrolled in the Halif ax Neural Transplantation Program who received bilateral putaminal transpla nts of fetal ventral mesencephalic tissue. A total of 16 transplantation op erations and 64 trajectories were performed in the eight patients, and ther e were no intraoperative or perioperative complications. Magnetic resonance imaging studies obtained 24 hours after surgery revealed no evidence of ti ssue damage or hemorrhage. Transplant survival was confirmed by fluorodopa positron emission tomography scans obtained 6 and 12 months after surgery. As neural transplantation procedures for the treatment of neurological cond itions evolve, the ability to deliver viable grafts safely will become crit ically important. The device presented here has proved to be of value in ma ximizing the number of graft deposits while minimizing implantation-related trauma to the host brain.