The effect of susceptibility of gadolinium contrast media on diffusion-weighted imaging and the apparent diffusion coefficient.
OBJECTIVE
The development of parallel magnetic resonance imaging has resulted in the frequent use of diffusion-weighted imaging (DWI) in clinical medicine, which usually involves the use of contrast medium. However, gadolinium (Gd) contrast medium may have some effect on DWI and the apparent diffusion coefficient (ADC). The present study was performed to determine whether the magnetic susceptibility of contrast medium alters the DWI signal and the value of ADC in some imaging techniques.


METHODS
Nonfat suppression DWI, short-time inversion recovery (STIR) combination, and chemical shift selective (CHESS) combination DWI were performed to examine 10 phantoms with gadolinium-meglumine gadopentetate (Gd-DTPA) dissolved at concentrations from 0.0005 to 0.1 mmol in physiologic saline as a contrast medium. The average pixel value and ADC of each method were determined.


RESULTS
ADC showed no differences between before and after treatment with contrast medium for all imaging techniques with Gd considered distributed over the whole tumor. The signal intensity did not change on nonfat suppression or CHESS combination DWI, but deteriorated on STIR.


CONCLUSIONS
ADC was not influenced by the magnetic susceptibility of contrast medium. In addition, it was suggested that the ability of tumor detection may be reduced if STIR is used as fat suppression.
Ogura
Akio
A
Department of Radiology, Kyoto City Hospital, 1-2 Higashitaka-cho, Mibu, Nakagyo-ku, Kyoto, Japan. a-ogura@mbox.kyoto-inet.or.jp
Hayakawa
Katsumi
K
Miyati
Tosiaki
T
Maeda
Fumie
F
D001932:Brain Neoplasms / Q000175:diagnosis* / Q000556:secondary; D003287:Contrast Media; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008579:Meningioma / Q000175:diagnosis*; D019047:Phantoms, Imaging
D003287:Contrast Media; D019786:Gadolinium DTPA