Fig. 2

The procedure was carried out on both the MRT2 model and the Sawbone model. (a, b, c, d) MRT2, and (e, f, g, h) Sawbone. (a, e) Setting of the model with navigation equipment. (b, f) Image of X-ray intensifier, (c, g) View on the navigation monitor, (d, h) CT scan image after screw placement. The MRT2 model is more clearly visible on X-ray and CT scan images. On the navigation monitor, the two-layer structure of the MRT2 appears more realistic compared to the Sawbone model