3 versus 7 Tesla magnetic resonance imaging for parcellations of subcortical brain structures in clinical settings

PLoS One. 2020 Nov 24;15(11):e0236208. doi: 10.1371/journal.pone.0236208. eCollection 2020.

Abstract

7 Tesla (7T) magnetic resonance imaging holds great promise for improved visualization of the human brain for clinical purposes. To assess whether 7T is superior regarding localization procedures of small brain structures, we compared manual parcellations of the red nucleus, subthalamic nucleus, substantia nigra, globus pallidus interna and externa. These parcellations were created on a commonly used clinical anisotropic clinical 3T with an optimized isotropic (o)3T and standard 7T scan. The clinical 3T MRI scans did not allow delineation of an anatomically plausible structure due to its limited spatial resolution. o3T and 7T parcellations were directly compared. We found that 7T outperformed the o3T MRI as reflected by higher Dice scores, which were used as a measurement of interrater agreement for manual parcellations on quantitative susceptibility maps. This increase in agreement was associated with higher contrast to noise ratios for smaller structures, but not for the larger globus pallidus segments. Additionally, control-analyses were performed to account for potential biases in manual parcellations by assessing semi-automatic parcellations. These results showed a higher consistency for structure volumes for 7T compared to optimized 3T which illustrates the importance of the use of isotropic voxels for 3D visualization of the surgical target area. Together these results indicate that 7T outperforms c3T as well as o3T given the constraints of a clinical setting.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Brain / diagnostic imaging*
  • Female
  • Globus Pallidus / diagnostic imaging
  • Humans
  • Magnetic Resonance Imaging / methods*
  • Male
  • Radiographic Image Interpretation, Computer-Assisted
  • Red Nucleus / diagnostic imaging
  • Substantia Nigra / diagnostic imaging
  • Subthalamic Nucleus / diagnostic imaging
  • Young Adult

Grant support

This research was supported by a Vidi and Vici grant from the Dutch Organization for Scientific Research (BUF), and an NWO-STW grant from the Dutch Organization for Scientific Research (BUF, MJM, AA).