Registration correction research of Robot of Stereotactic Assistant system

doi:10.11850/j.issn.1009-122X.2017.02.013

Abstract：Objective To explore the effects of positional relationship between the probe circle and the bony landmark on registration error when Robot of Stereotactic Assistant (ROSA) system makes registration plan. Methods Sixteen bony landmarks were fixed on the head model and CT scan was performed, and the data was imported into the ROSA system. Five out of the 16 bony landmarks were randomly selected to register every time. There were 3 types of registration schemes. Group A registration plan: the probe circle was tangent to the tail end edge of the bony landmark. Group B and Group C were moved to the tip of the bony landmarker and 0.5 mm in the negative direction. Fifteen tests were performed and registration 45 times. The results were analyzed using paired t test. Results The error range of Group A was 0.42-0.77 mm, and the average value was 0.557 ± 0.105 mm. The error range of Group B was 0.23-0.68 mm, and the average value was 0.349 ± 0.109 mm. The error range of Group C was 0.64-1.12 mm, and the average value was 0.897 ± 0.145 mm. The difference in error betwen Group A and Group B was statistically significant, and the error of Group B was smaller (t=8.16, P<0.001). The error of Group A and Group C was statistically significant, and the error of Group A was smaller (t=12.93, P<0.001). According to the error from large to small, the order was Group C>Group A>Group B. Conclusions The registration error of ROSA can be reduced by moving the probe circle towards the tip of the landmark by 0.5 mm.