Effect of imaging time in the magnetic resonance detection of intracerebral metastases using single dose gadobutrol.
OBJECTIVE
To compare the effect of imaging time delay on the MR detection of intracerebral metastases using single dose gadobutrol.


METHODS
Twenty-one patients with intracerebral metastases underwent contrast-enhanced MR with three-dimensional T1-weighted sequence at 1 minute, 5 minutes and 10 minutes after a single dose injection of gadobutrol. One hundred index metastatic lesions (1 to 30 mm; median, 7 mm) were chosen for the analysis. For the qualitative analysis, lesion conspicuity were assessed on a 1 (worst) to 5 (best) scale of the index lesions by an expert reader. For the quantitative analysis, signal intensity (SI) of enhancing lesions and normal parenchyma was measured to determine the contrast rate (CR, %) ([postcontrast SI lesion - postcontrast SI white matter] × 100 / postcontrast SI white matter) and the enhancement rate (ER, %) ([postcontrast SI lesion - baseline SI gray matter] × 100 / baseline SI gray matter). Statistical comparisons were made between three different time delays.


RESULTS
Lesion conspicuity did not differ significantly among the three time delays (p = 0.097). Although the SI, CR and ER of lesions did not reveal any significant difference between 1 minute and 5 minutes delayed images, both the 1 minute and 5 minutes delayed images showed significantly higher CRs of lesions compared with the 10 minutes delayed images (p = 0.004 and p = 0.001, respectively).


CONCLUSIONS
With single dose gadobutrol, imaging time delay did not have an effect on lesion conspicuity. Both 1-minute and 5-minute-delayed imaging after gadobutrol injection appears to be effective for the detection of intracerebral metastases.
Department of Radiology, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul 143-914, Korea.
Ji-Young
JY
Jeon
Department of Radiology, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul 143-914, Korea.
Jin Woo
JW
Choi
Department of Radiology, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul 143-914, Korea.
Hong Gee
HG
Roh
Department of Radiology, Konkuk University Medical Center, Konkuk University School of Medicine, Seoul 143-914, Korea.
Won-Jin
WJ
Moon
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001932:Brain Neoplasms / Q000175:diagnosis* / Q000556:secondary*; D003287:Contrast Media / Q000008:administration & dosage; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D009942:Organometallic Compounds / Q000008:administration & dosage; D013997:Time Factors
D003287:Contrast Media; D009942:Organometallic Compounds; C090600:gadobutrol
Contrast agent; Gadovist; Intracerebral metastases; MRI; Single dose gadobutrol