An image registration apparatus comprises: a features detector (34) configured to extract a two-dimensional set of features (36) from a two-dimensional image (30) and to extract a three-dimensional set of features (38) from a three-dimensional image (32); a projection processor (40) configured to project three-dimensional data into two-dimensional projection data; and a registration processor (46, 52) configured to (i) adjust parameters to register the two-dimensional set of features and the three-dimensional set of features projected by the projection processor using a projection geometry (42), and to (ii) use the adjusted parameters to register the two-dimensional image and the three-dimensional image projected by the projection processor using the projection geometry.