Electrophysiology-guided deep brain neurosurgery

Abstract

Since the discovery of X-rays, medical imaging has played a major role in the guidance of surgical procedures. Recent advances in computer technology have only accelerated the rapid development of this field. As interventions become significantly less invasive, the use of pre-operative and intra-operative images to guide surgery has assumed increasing importance. Image-guided techniques have been employed for many years to plan and guide neurosurgical procedures. Amongst the most challenging areas of neurosurgery is the accurate targeting of nuclei within the deep brain for the treatment of Parkinson's and other motor system diseases. Unfortunately, standard CT and MR imaging does not permit the anatomical delineation of the targets, and so additional information, for example atlases and electrophysiological data, must also be employed. Both these forms of data can be mapped, using non rigid image registration techniques, to a standard representation of a brain acquired from MRI. The electrophysiology database can also evolve over time with the incorporation of data acquired from multiple patients operated in the past. Information of this nature can then be incorporated within the patient image, and serve as an invaluable tool in predicting to the surgeon the likely area of the target. This approach can significantly reduce the trauma associated with the insertion of multiple unnecessary electrodes to refine the target location, and speed up the procedure.

A Field Guide to Finding Fossils on Mars

“…Organic material can also survive when passively entombed by rapid precipitation, as in Precambrian marine cherts and Phanerozoic hydrothermal sinters (e.g., Campbell et al, 2015;Pancost et al, 2006;Schultze-Lam et al, 1995;Yee et al, 2003). Organic molecules with robust chemical backbones can be indicative of general or specific biological origins (i.e., "biomarkers" or "molecular fossils") and are common in fine-grained sedimentary rocks (Peters et al, 2005;Summons & Lincoln, 2012).…”