Abstract: The ionization potential of a tissue can be assessed by determining the water content, organic content, and mineral content of the tissue. The methods of determining ionization potential provided here may be implemented by MRI. In one method, ionization potential in soft tissues is achieved by measurement of two tissue parameters: the (1) the amount of water, as a percentage by mass; and (2) the organic hydrogen content of the tissue. Measurement of a third parameter, phosphorous density, allows for calculation of Im in tissues comprising mineralized components. The methods enable more accurate SPR calculation and improved heavy charged particle targeting in radiotherapy.

Abstract: This invention provides computerized image guidance systems for deep brain stimulation (DBS) surgery and related methods that improve accuracy of positioning of electrodes in the brains of subjects. Image guidance systems in accordance with the present invention incorporate advanced features such as capability of displaying, in any desired plane of view, a digitized three-dimensional neuroanatomical brain map that can be form fitted to a patient's medical images, such as brain MR images, and capability of displaying on the patient's medical images both the contours of anatomic structures from a digitized brain map, and digitized electrode recording data obtained intra-operatively.