BACKGROUND/AIMS: To evaluate the use of the NeuroMate stereotactic robot with a 
novel ultrasound registration system for movement disorder surgery (MDS).
METHODS: Using the robot in a frameless mode, 51 patients underwent MDS. 
Surgical planning was carried out using MRI data obtained more than 24 h before 
surgery.
RESULTS: 37 out of 50 targets in the subthalamic nucleus were satisfactorily 
identified with a single microelectrode trajectory and the final electrode 
positions were at a mean distance of 1.7 mm from the calculated target. There 
was a significant improvement in motor scores of the Unified Parkinson's Disease 
Rating Scale III (off medication) at 6 (43%) and 18 months (51.7%) compared to 
pre-operative scores (p < 0.05).
CONCLUSIONS: The frameless robot using only MRI data can be used for MDS. The 
temporal separation of imaging from the surgical procedure provides additional 
time for detailed image analysis and planning.