Sensitivity of immediate and delayed gadolinium-enhanced MRI after injection of 0.5 M and 1.0 M gadolinium chelates for detecting multiple sclerosis lesions.
OBJECTIVE
The purpose of our study was to compare the efficacy of cranial MR images obtained immediately after, 5 minutes after, and 10 minutes after the injection of 0.5-mol/L (Magnevist) and 1.0-mol/L (Gadovist) gadolinium chelates in the detection of active multiple sclerosis (MS) lesions.


METHODS
Thirty patients with MS were examined with MRI first with 0.5-mol/L and then, after 24-48 hours, with 1.0-mol/L gadolinium chelates. T1-weighted spin-echo images with magnetization transfer were obtained immediately, 5 minutes, and 10 minutes after the injection of the contrast material. Three radiologists evaluated the gadolinium-enhanced T1-weighted images on a remote MR console (Advantage Windows) in six separate sessions and counted the number of enhancing lesions in consensus.


RESULTS
Significantly fewer enhancing lesions were seen on MR images immediately after the injection of 0.5- and 1.0-mol/L gadolinium chelates (n = 18 and n = 36, respectively; p < 0.05) than at 5 minutes (n = 32 and n = 54; p < 0.05) and 10 minutes (n = 34 and n =55; p < 0.05) after the injection (p < 0.05). Likewise, significantly fewer patients with at least one enhancing lesion after the injection of 0.5- and 1.0-mol/L gadolinium chelates (n = 10 and n = 16; p < 0.05) were found immediately after injection than were found 5 minutes (n = 18 and n = 24; p < 0.05) and 10 minutes (n = 18 and n = 24; p < 0.05) after injection (p < 0.01).


CONCLUSIONS
The use of 1.0-mol/L gadolinium chelate enables us to detect an increased number of enhancing lesions and patients with active disease. A delay of 5 minutes after the injection of the gadolinium chelate might be sufficient to detect active lesions in patients with MS.
Uysal
Ender
E
Department of Radiology, Sisli Etfal Hospital, Etfal Sok, Istanbul 80220, Turkey. enderuysaltr@yahoo.com
Erturk
Sukru Mehmet
SM
Yildirim
Hakan
H
Seleker
Feray
F
Basak
Muzaffer
M
D000328:Adult; D001921:Brain / Q000473:pathology*; D002614:Chelating Agents / Q000008:administration & dosage; D003287:Contrast Media / Q000008:administration & dosage; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D005260:Female; D005682:Gadolinium / Q000008:administration & dosage*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007269:Injections, Intra-Arterial; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D009103:Multiple Sclerosis / Q000473:pathology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013997:Time Factors
D002614:Chelating Agents; D003287:Contrast Media; D005682:Gadolinium