Fig.1.

Transfrontal versus Posterior (occipital) trajectories utilizing CED. MRI-guided stereotactic approaches for vector delivery to the putamen utilizing convection enhanced delivery (CED) and stepped cannulae. This approach allows for precise targeting, shape-fitting infusions, and larger delivery volumes to improve the extent of transduced putaminal tissue, thereby increasing transgene production capacity. With the transfrontal approach, the cannulae are oriented to the short axis of the putamen limiting vector coverage to <30%, often requiring 2-3 tracts. The posterior (occipital) approach maximizes the delivery by paralleling the putaminal long-axis, requiring only 1 tract, which achieves >50% putaminal vector coverage with larger infusion volumes.