Co-Registration of the Schaltenbrand-Wahren Microseries with the Probabilistic Functional Atlas

Objective: The Schaltenbrand-Wahren atlas (SWA) is anatomical, sparse and inconsistent in three dimensions. A high-resolution, electrophysiology-based atlas derived from numerous specimens overcomes these limitations. A combined anatomy-physiology atlas leverages the strengths and complementarity of both, which is studied here. Method: An electronic version of the SWA was constructed. A probabilistic functional atlas (PFA) was developed from electrophysiological and neuroimaging data with 0.25 mm3 resolution. A combined atlas is constructed by co-registering the PFA with the SWA by applying linear scaling along the intercommissural distance and the height of the thalamus. Results: An anatomy-physiology atlas is superior to its component atlases. When in register, the anatomical and functional atlases are displayed together and used simultaneously. A structure of interest from the PFA can be displayed with high resolution, compensating for its sparseness in the SWA, while its surrounding structures are obtained from the SWA. The best anatomical and functional targets can be compared: for the subthalamic nucleus, the horizontal and lateral coordinates of the SWA-based and PFA- based targets are approximately the same, while the latter is located 1.3–1.5 mm more anteriorly. Conclusion: An anatomy-physiology atlas may enhance the accuracy of targeting and increase the neurosurgeon’s confidence. It also opens new research avenues to serve as a reference for: (1) constructing an extendable atlas by adding new electrophysiological data, (2) comparing anatomical and functional targets, (3) studying and comparing various symptoms, and (4) comparing image-based targets obtained from various modalities.