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

Abstract and Introduction

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.
Materials and 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).
Conclusion: 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.

Gadolinium-enhanced brain MRI has become the most sensitive tool for confirming the diagnosis of multiple sclerosis (MS) and for monitoring MS treatment trials.^[1] In longitudinal clinical studies, the presence of at least one enhancing (i.e., active) lesion at screening is an established entry criterion for therapy.^[2,3] Hence, to show one or no enhancing lesions is an important clinical and research goal.^[4]

The sensitivity of gadolinium-enhanced MRI may be improved by means of magnetization transfer or by increasing the concentration of gadolinium in the tissues by increasing the injected volume of 0.5-mol/L gadolinium chelates or by increasing the delay between injection and the imaging sequences.^[1,5,6]

Although the use of magnetization transfer has become commonplace for patients with MS, the optimal gadolinium dose and the optimal scan timing are still controversial. Furthermore, a new MRI contrast agent with double gadolinium concentration (molarity) has recently been introduced into clinical practice and deserves to be investigated in this context.

In this study, our aim was to compare the ability of cranial MR images obtained immediately, 5 minutes, and 10 minutes after the injection of 0.5-mol/L (Magnevist [gadopentetate dimeglumine], Schering) and 1.0-mol/L (Gadovist [gadobutrol], Schering) gadolinium chelates in the detection of active MS lesions. To our knowledge, ours is the first study to compare 0.5-and 1.0-mol/L gadolinium chelates in the clinical setting of MS.

Am J Roentgenol. 2007;188(3):697-702. © 2007 American Roentgen Ray Society

Cite this: 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 - Medscape - Mar 01, 2007.