Brain mapping in stereotactic surgery: A brief overview from the probabilistic targeting to the patient-based anatomic mapping

Abstract

In this article, we briefly review the concept of brain mapping in stereotactic surgery taking into account recent advances in stereotactic imaging. The gold standard continues to rely on probabilistic and indirect targeting, relative to a stereotactic reference, i.e., mostly the anterior (AC) and the posterior (PC) commissures. The theoretical position of a target defined on an atlas is transposed into the stereotactic space of a patient's brain; final positioning depends on electrophysiological analysis. The method is also used to analyze final electrode or lesion position for a patient or group of patients, by projection on an atlas. Limitations are precision of definition of the AC-PC line, probabilistic location and reliability of the electrophysiological guidance. Advances in MR imaging, as from 1.5-T machines, make stereotactic references no longer mandatory and allow an anatomic mapping based on an individual patient's brain. Direct targeting is enabled by high-quality images, an advanced anatomic knowledge and dedicated surgical software. Labeling associated with manual segmentation can help for the position analysis along non-conventional, interpolated planes. Analysis of final electrode or lesion position, for a patient or group of patients, could benefit from the concept of membership, the attribution of a weighted membership degree to a contact or a structure according to its level of involvement. In the future, more powerful MRI machines, diffusion tensor imaging, tractography and computational modeling will further the understanding of anatomy and deep brain stimulation effects.

Influence of heterogeneous and anisotropic tissue conductivity on electric field distribution in deep brain stimulation

“…Yousif et al [26] DTI is performed in some institutions in order to analyse white matter fascicles when planning trajectories during primary anatomical targeting during DBS [44].…”

Generation of Individualized Thalamus Target Maps by Using Statistical Shape Models and Thalamocortical Tractography

“…[1][2][3] Various methods have been developed to map, organize, and use the prior topographic information of thalamic subdivisions that are provided by anatomic stereotactic atlases. [4][5][6][7][8] In parallel to the effort of providing stereotactic atlases that incorporate clinical imaging-based anatomic correspondences, 9 it is desirable to optimize MR imaging sequences and image-processing techniques for the direct identification of thalamic nuclei. [10][11][12] A promising technique to noninvasively chart the human thalamus is diffusion tensor imaging 13 and subsequent probabilistic tractography, which can be applied to map the networks of thalamocortical connectivity.…”

Stereotactic implantation of deep brain stimulation electrodes: a review of technical systems, methods and emerging tools

“…Some centres acquire stereotactic MRI the day of implantation just before surgery [23], while others perform the MRI the day before surgery and reposition the stereotactic frame the day of surgery [73]. More often, an MRI is acquired some days before the implantation to be merged with a stereotactic CT of the day of surgery [88,110].…”

“…More often, an MRI is acquired some days before the implantation to be merged with a stereotactic CT of the day of surgery [88,110]. Tesla MRI anatomy software [73].…”