Hans Ulrich Kerl, Presenter: Nothing to Disclose

Lars Gerigk, Abstract Co-Author: Nothing to Disclose

Ioannis Pechlivanis, Abstract Co-Author: Nothing to Disclose

Christoph Groden MD, Abstract Co-Author: Nothing to Disclose

Ingo Nölte, Abstract Co-Author: Nothing to Disclose

The subthalamic nucleus (STN) is one of the most common target structures used for deep brain stimulation-treatment for advanced Parkinson’s disease. The success of the stereotactic intervention of the STN hereby critically depends on the reliable identification of the STN. The improved MRI technology has increasingly influenced stereotactical planning. With the availability of clinical 3.0-Tesla MRI direct targeting of the STN became more reliable, which is more appropriate for individual patients considering the given anatomical variability in position, size, and functional segregation of the target nuclei . The purpose of our study was to determine the optimal sequence and orientation at 3.0-Tesla magnetic resonance imaging (MRI) for preoperative visualization of the subthalamic nucleus for stereotactic targeting.  

MRI of nine healthy volunteers and of one patient with Parkinson’s disease was acquired (T2-FLAIR, T1-MPRAGE, T2-FLASH2D, T2-SPACE and susceptibility-weighted imaging (SWI)). Two radiologists independently analyzed image quality and visualization of the STN for each sequence. Inter-rater reliability was calculated. Contrast-to-noise ratios (CNR) and signal-to-noise ratios (SNR) for the STN were computed. For illustration, the coronal FLASH2D images were fused with the digitized coronal section schema of the Schaltenbrand-Wahren stereotactic atlas. Finally, pre- and postinterventional CT and MRI of one patient with PD are presented.

The STN was best and reliably visualized in T2-FLASH2D- (particularly coronal view) and SWI images. No major artifacts in the target area were observed in any of the sequences. SWI offered a significant higher CNR for STN compared to standard T2-weighted imaging. The fusion of the coronal T2-FLASH2D and the digitized coronal atlas view projected the STN clearly into the boundaries of the STN found in anatomical sections. For the Parkinson's disease patient fused pre- and postoperative imaging demonstrated the correct placement of the electrodes in the STN.  

For 3-Tesla MRI T2-FLASH2D (particularly coronal view) and SWI provide optimal delineation of the STN.

The direct visualization and location of the STN using 3.0-Tesla MRI leads to a more precise STN targeting and may facilitate a reduction of the intervention time in deep brain surgery.

Kerl, H, Gerigk, L, Pechlivanis, I, Groden, C, Nölte, I, Imaging of the Subthalamic Nucleus at 3.0 Tesla: Choice of Optimal Sequence and Orientation for Deep Brain Stimulation.  Radiological Society of North America 2011 Scientific Assembly and Annual Meeting, November 26 - December 2, 2011 ,Chicago IL. http://archive.rsna.org/2011/11015380.html