Figure 4From: The effects of computed tomography image characteristics and knot spacing on the spatial accuracy of B-spline deformable image registration in the head and neck geometryRegistration accuracy for varying image feature content. The MRD as function of BKS for phantoms with varying disc spacings (phantom XV-XVII) (see phantom properties in Table 1). Abbreviations: MRD = mean residual displacement, BKS = B-spline knot spacing.Back to article page