Triple-dose versus single-dose gadoteridol in multiple sclerosis patients

Nine patients with multiple sclerosis underwent brain magnetic resonance imaging (MRI) to evaluate the contrast enhancement of individual lesions after a single dose and a triple dose of gadolinium. A single dose (0.1 mmol/kg) of gadoteridol was administered and after a delay, axial T1-weighted images were obtained. After an additional 0.2-mmol/kg dose, the same T1-weighted sequence was repeated. An unblinded reader simultaneously viewed the images from both doses, and utilizing a computer console to rule out flow artifacts, created a gold standard of "definite" enhancing lesions. Using this system, he determined that there was a total of 12 definite enhancing lesions among the patients. This reader also evaluated lesion conspicuity. The contrast-noise ratio was calculated for each lesion. A second reader, blinded to the dose used, then evaluated the number of enhancing lesions at both doses. The unblinded reader noted increased lesions at both doses. The unblinded reader noted increased lesion conspicuity after the triple dose. Contrast-noise ratios were significantly (p < 0.001) higher after the triple dose (mean, 9.19) than after the single dose (mean, 2.97). The blinded reader detected 11 of the 12 definite lesions on MRIs after the triple dose (sensitivity, 92%) but saw only 6 on MRIs after the single dose (sensitivity, 50%). The difference was significant (p < 0.001). Subjective analysis of the films revealed an increase in "ghosting artifacts" at the high dose. Administration of triple-dose gadolinium provides increased lesion conspicuity and an improved lesion detection rate when compared to single-dose gadolinium in patients with multiple sclerosis.