Neural network methods for volumetric magnetic resonance imaging of the human brain

Multimedia, including imaging and videoconferencing, is becoming the predominant mode of professional and technical communication. In the medical arena, multimedia systems will have to deal with images of different types, including live videos of the participants in a video conference, and still images or videos of radiological or magnetic resonance (MR) information. In the last 30 years there has been an explosion in our knowledge of the biochemical machinery of the nervous system. This knowledge has been primarily developed from in vitro and in vivo experiments in invertebrates and mammals. In the last few years with the advent of new imaging technologies such as magnetic resonance imaging (MRI) and positron emission tomography (PET) it has become possible to explore the integrated central nervous system (both biochemically nad biophysically) in living humans. A major limitation in utilizing these techniques in an optimal fashion has been the lack of sophisticated image analysis systems which can extract the relevant information from the images in an automated or semiautomated manner. Brain MR images contain massive information requiring lengthy and complex interpretation (as in the identification of significant portions of the image), quantitative evaluation (as in the determination of the size of certain significant regions), and sophisticated interpretation (as in determining any image portions which indicate signs of lesions or of disease). In this paper we first survey the clinical and research needs for brain imaging. We present the state-of-the art in relevant image analysis techniques. We then discuss our recent work on the use of novel artificial neural networks which have a recurrent structure to extract precise morphometric information from MRI scans of the human brain. Finally, experimental data using our novel approach is presented and suggestions are made for future research.