Optimal MRI methods for direct stereotactic targeting of the subthalamic nucleus and globus pallidus
- First Online:
- Cite this article as:
- O’Gorman, R.L., Shmueli, K., Ashkan, K. et al. Eur Radiol (2011) 21: 130. doi:10.1007/s00330-010-1885-5
- 541 Downloads
Reliable identification of the subthalamic nucleus (STN) and globus pallidus interna (GPi) is critical for deep brain stimulation (DBS) of these structures. The purpose of this study was to compare the visibility of the STN and GPi with various MRI techniques and to assess the suitability of each technique for direct stereotactic targeting.
MR images were acquired from nine volunteers with T2- and proton density-weighted (PD-W) fast spin echo, susceptibility-weighted imaging (SWI), phase-sensitive inversion recovery and quantitative T1, T2 and T2* mapping sequences. Contrast-to-noise ratios (CNR) for the STN and GPi were calculated for all sequences. Targeting errors on SWI were evaluated on magnetic susceptibility maps. The sequences demonstrating the best conspicuity of DBS target structures (SWI and T2*) were then applied to ten patients with movement disorders, and the CNRs for these techniques were assessed.
SWI offers the highest CNR for the STN, but standard PD-W images provide the best CNR for the pallidum. Susceptibility maps indicated that the GPi margins may be shifted slightly on SWI, although no shifts were seen for the STN.
SWI may improve the visibility of the STN on pre-operative MRI, potentially improving the accuracy of direct stereotactic targeting.
KeywordsMRI Deep brain stimulation Direct stereotactic targeting Subthalamic nucleus Globus pallidus
deep brain stimulation
driven equilibrium single-pulse observation of T1
fast spin echo
globus pallidus interna
inversion recovery prepared fast spoiled gradient echo volume
phase sensitive inversion recovery