2-D to 3-D refinement of post-mortem optical and MRI co-registration

Accurate co-registration of MR images of the brain with pathological data from the same patient is required for many applications, including validation of in-vivo MRI processing. We present preliminary results from a 2-D optical to 3-D MRI registration process, which depends on initialisation using an initial 3-D reconstruction of post-mortem whole-brain or hemisphere slices from independent 2D images followed by 3-D to 3-D registration. Our overall approach progressively models the acquisition process, and the final stages account for variations in slice thickness and other errors that can occur as a result of the specimen preparation and earlier processing. Our method can be used in most neuropathology laboratories where thick slices are cut. Alternative approaches depend on sectioning by macrocryotomes, which are not generally available and have limited applicability in conditions such as CJD where infectivity risks are high.