Diffusion tensor imaging in patients with adult chronic idiopathic hydrocephalus.
OBJECTIVE
Diffusion tensor imaging (DTI) parameters were investigated in patients with chronic idiopathic hydrocephalus to evaluate microstructural changes of brain tissue caused by chronic ventricular dilatation.


METHODS
Eleven patients fulfilling the criteria for possible or probable idiopathic normal pressure hydrocephalus and 10 healthy control subjects underwent MRI at 3 Tesla, including DTI with 12 gradient directions. Patients were scanned before lumbar cerebrospinal fluid (CSF) withdrawal tests. Differences in fractional anisotropy (FA) and mean diffusivity (MD) between patients and controls were assessed using 2 different methods: manual definition of regions of interest and a fully automated method, TBSS (Tract-Based Spatial Statistics). DTI parameters were correlated with clinical findings.


RESULTS
Compared with the control group, patients with chronic idiopathic hydrocephalus had significantly higher MD values in both the periventricular corticospinal tract (CST) and the corpus callosum (CC), whereas FA values were significantly higher in the CST but lower in the CC. DTI parameters of the CST correlated with the severity of gait disturbances.


CONCLUSIONS
Microstructural changes in periventricular functionally relevant white matter structures (CSF, CC) in chronic idiopathic hydrocephalus can be visualized using DTI. Further studies should investigate the change of DTI parameters after CSF shunting and its relation to neurologic outcome.
Hattingen
Elke
E
Institute of Neuroradiology, Goethe University, Frankfurt am Main, Germany. elke.hattingen@kgu.de
Jurcoane
Alina
A
Melber
Julia
J
Blasel
Stella
S
Zanella
Friedhelm E
FE
Neumann-Haefelin
Tobias
T
Singer
Oliver C
OC
D000368:Aged; D016880:Anisotropy; D001921:Brain / Q000473:pathology*; D002908:Chronic Disease; D056324:Diffusion Tensor Imaging; D006801:Humans; D006850:Hydrocephalus, Normal Pressure / Q000473:pathology*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008875:Middle Aged