Image Guided Neurosurgery Core
Alexandra Golby, M.D., Core PI
Neurosurgical planning and intraoperative brain mapping are the principle activities of the Image Guided Neurosurgery Core, as a major challenge in brain surgery is the identification and preservation of eloquent cortex, so as to avoid post-operative neurological deficits.
Cycle II 2010-1015
Objectives
The projects of the Neurosurgery Core aim to put advanced IGT tools into the hands of surgeons to allow them to perform safer and more efficient neurosurgical interventions. Over the last few decades, intracranial surgery has been transformed from a dangerous, unpredictable intervention that many patients would not survive or would be left with major neurological deficits to a routine elective procedure with most patients leaving the hospital in a few days usually in better or an equivalent neurologic condition than they were preoperatively. The change is due to the tremendous advances in imaging, visualization, and operative techniques that allow the surgeon to have a much better understanding of the anatomy and pathology that are the targets of the intervention. Nevertheless, there remain many times when neurosurgeons find themselves uncertain of how to proceed due to a lack of information. An important example is in surgery for primary brain tumors that arise from the brain parenchyma and may variably infiltrate, compress, or destroy brain tissue and that can be very difficult to differentiate from normal brain tissue. All brain surgery needs to consider the functional organization of the brain tissue around the lesion to avoid causing a new neurologic deficit. However, differentiating critical functional areas from areas that can be resected is not possible either on conventional imaging or by inspection at the time of surgery. To decide whether surgery is feasible for a patient with a given lesion, the surgeon requires a complete and accurate map of the complex and critical functional anatomy of that individual’s brain. A further challenge results from the progressive deformation of anatomy that takes place during the surgical intervention (brain shift), making preoperative images and associated neuronavigation increasingly inaccurate. To address these major issues in modern neurosurgery, we propose to develop IGT tools that give surgeons improved information to make decisions pre- and intraoperatively. The Neurosurgery Core will develop and test a novel IGT tools: a multimodality atlas using functional MRI and Diffusion Tensor Imaging (SA1) to identify and display important white matter tracts. This multidisciplinary translational research effort will take advantage of the new Advanced Multimodality Image Guided Operating (AMIGO) suite at the BWH that will be a setting to develop and test IGT approaches. Our team brings together specialists in clinical neurosurgery, imaging, image processing, chemistry, physics, engineering and computer science to address real clinical problems faced by surgeons and their patients everyday and to develop tools that can be broadly applied at many medical centers.
Specific Aim
Specific Aim: Semi-automatic identification of neurosurgically important white matter tracts using fMRI+DTI atlas. We will harness emerging methods to improve the sensitivity and specificity of fMRI and DTI to help demonstrate the functional organization of grey and white matter in individual patient brains. We will first generate a novel statistical atlas characterizing the normal range of shape and diffusion values of major white matter tracts such as the corticospinal tract and optic radiations and their spatial relationship to fMRI activations. Then, to locate these tracts in patients, we will develop a semi-automatic atlas-based segmentation method designed to be robust enough to displace and locate partial tracings due to edema. By employing two-tensor tractography, we will better trace tracts through regions of fiber crossing to allow clinically important tracts, such as the corticospinal tract linking the hand area of the cortex, to be visualized. Furthermore, the atlas will be the basis for identifying displaced or otherwise abnormal regions within the tracts (regions whose shape or diffusion lies outside the normal range) to highlight these regions for the neurosurgeon.
NCIGT Publications
- Golby A.J., Kindlmann G., Norton I., Yarmarkovich A., Pieper S., Kikinis R. Interactive Diffusion Tensor Tractography Visualization for Neurosurgical Planning. Neurosurgery. 2011 Feb; 68(2):496-505. PMID: 21135713.
- Elhawary H., Liu H., Patel P., Norton I., Rigolo L., Papademetris X., Hata N., Golby A.J. Intra-operative Real-time Querying of White Matter Tracts during Frameless Stereotactic Neuronavigation. Neurosurgery. In Press. PMID: 21135719.
- O'Donnell L., Westin C-F., Norton I., Whalen S., Rigolo L., Propper R., Golby A.J. The Fiber Laterality Histogram: A New Way to Measure White Matter Asymmetry. Int Conf Med Image Comput Comput Assist Interv. 2010;13(Pt 2):225-32. PMID: 20879319. PMCID: PMC2999578.
- Propper R.E., O'Donnell L.J., Whalen S., Tie Y., Norton I.H., Suarez R.O., Zollei L., Radmanesh A., Golby A.J. A Combined FMRI and DTI Examination of Functional Language Lateralization and Arcuate Fasciculus Structure: Effects of Degree Versus Direction of Hand Preference. Brain Cogn. 2010 Jul;73(2):85-92. PMID: 20378231. PMCID: PMC2880216.
Projects
NCIGT projects in which the Neurosurgery Core provides leadership and central input are:
Cycle I 2005-2010
The NCIGT's Neurosurgery Core has in its first cycle combined preoperative, high-resolution functional MRI (fMRI), diffusion tensor imaging (DTI), and intraoperative electrophysiologic testing (ECS) in patients with brain tumors in and adjacent to eloquent cortex so as to accomplish the following general goals:
- develop high-resolution techniques for presurgical fMRI acquisition and analysis
- establish the validity of diffusion tensor imaging for identifying eloquent white matter tracts and their relationship to brain tumors
- develop methods which will improve the accuracy of preoperative functional brain mapping
- improve post-operative neurologic outcomes for patients with tumors in and adjacent to motor and language cortical areas.
These general goals have been supported by the continued development and implementation of the most advanced data collection methods and analysis tools and through ongoing collaborations with other researchers and clinicians in neurosurgery, radiology, engineering, and computer science at ours and affiliated institutions.