Normal fusion for three-dimensional integrated visualization of SPECT and magnetic resonance brain images

Multimodality visualization aims at efficiently presenting integrated information obtained from different modalities, usually combining a functional modality (SPECT, PET, functional magnetic resonance imaging) with an anatomical modality [CT, magnetic resonance imaging (MRI)]. This paper presents a technique for three-dimensional integrated visualization of SPECT and magnetic resonance brain images, where MRI is used as a framework of reference for the display of the SPECT data. Methods: A novel technique for three-dimensional integrated visualization of functional and anatomical information, called normal fusion, is presented. With this technique, local functional information is projected onto an anatomic structure. Results: The normal fusion technique is applied to three cases of SPECT/MRI integration. The results are presented, discussed and evaluated for clinical relevance. Conclusion: The results for three-dimensional integrated display of SPECT and MR brain images indicate that the normal fusion technique provides a potentially comprehensive and diagnostically valuable presentation of cerebral blood perfusion in relation to the anatomy of the brain.