Positional brain deformation visualized with magnetic resonance morphometry.
OBJECTIVE
To assess and visualize gravitational effects on brain morphology and the position of the brain within the skull by magnetic resonance (MR) morphometry in order to identify confounding effects and possible sources of error for accurate planning of neurosurgical interventions.


METHODS
Three-dimensional MR imaging data sets of 13 healthy adults were acquired in different positions in the scanner. With a morphometric approach, data sets were evaluated by deformation field analysis and the brain boundary shift integral. Distortions of the brain were assessed comparing right versus left and prone versus supine positioning, respectively.


RESULTS
Two effects could be differentiated: 1) greatest brain deformation of up to 1.7 mm predominantly located around central brain structures in the lateral direction and a less pronounced change after position changes in posterior-anterior direction, and 2) the brain boundary shift integral depicted position-dependent brain shift relative to the inner skull.


CONCLUSIONS
Position-dependent effects on brain structure may undermine the accuracy of neuronavigational and other neurosurgical procedures. Furthermore, in longitudinal MR volumetric studies, gravitational effects should be kept in mind and the scanning position should be rigidly controlled for.
Schnaudigel
Sonja
S
Department of Neurology, Friedrich-Schiller-University, Jena, Germany.
Preul
Christoph
C
Ugur
Tarik
T
Mentzel
Hans Joachim
HJ
Witte
Otto W
OW
Tittgemeyer
Marc
M
Hagemann
Georg
G
D000328:Adult; D000465:Algorithms; D001921:Brain / Q000473:pathology*; D001927:Brain Diseases / Q000473:pathology*; D005260:Female; D007839:Functional Laterality; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D013238:Stereotaxic Techniques; D055815:Young Adult