T1-weighted functional imaging based on a contrast agent in presurgical mapping.
OBJECTIVE
To assess the applicability of T1-weighted images in the presence of a contrast agent for functional mapping free of susceptibility artifacts, in comparison to the blood oxygenation level-dependent (BOLD) imaging.


METHODS
Six patients and five control subjects were scanned using BOLD and T1-weighted functional imaging, in the presence of a Gd-DTPA contrast-agent (TOFICA). In the control group, low- and high-resolution BOLD images were performed. Functional stimuli included motor and language activations.


RESULTS
Both BOLD and TOFICA methods resulted in activations in the expected anatomical regions. The TOFICA mapping gave less distributed and with higher percent signal changes in comparison with the BOLD images. Gd-DTPA remained almost constant in the blood for at least 15 min post injection. In one patient with surgical clips, no signal was detected in the left cerebral hemisphere using BOLD imaging, but activation could be mapped using the TOFICA method.


CONCLUSIONS
T1-weighted imaging in the presence of a contrast agent can be used for functional mapping. This method is insensitive to susceptibility artifacts, and is therefore advantageous in the evaluation of presurgical cases and in areas of the brain close to cavities in which the BOLD method cannot reliably be applied.
Ben Bashat
Dafna
D
The Functional Brain Imaging Center, The Wohl Institute for Advanced Imaging, Department of Radiology, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel. dafnab@;tasmc.health.gov.il
Sivan
Ida
I
Ziv
Michal
M
Aizenstein
Orna
O
Pianka
Pazit
P
Malach
Rafael
R
Graif
Moshe
M
Hendler
Talma
T
Navon
Gil
G
D000328:Adult; D000465:Algorithms; D016477:Artifacts; D001921:Brain / Q000473:pathology* / Q000601:surgery*; D001931:Brain Mapping / Q000379:methods*; D003287:Contrast Media; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011300:Preoperative Care; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055815:Young Adult
D003287:Contrast Media; D019786:Gadolinium DTPA