Contrast-enhanced MR imaging of the breast: comparison of two different doses of gadopentetate dimeglumine.

PURPOSE

To optimize detection and diagnosis of breast lesions with contrast-enhanced magnetic resonance (MR) imaging.

MATERIALS AND METHODS

A three-dimensional fast low-angle shot pulse sequence was used for a group comparison consisting of 76 high-dose (0.16 mmol gadopentetate dimeglumine per kilogram of body weight) and 76 low-dose (0.1 mmol/kg) examinations. Intraindividual comparisons were possible in a subgroup of 20 patients.

RESULTS

Enhancement with the high dose was about 1.5 times higher for benign and malignant tissues. With the lower dose, no false-positive findings could be avoided and definition of a threshold that excluded false-negative findings was problematic. Conspicuity of malignant lesions was much improved with the higher dose (a good to excellent rating in 81% vs 26% with the lower dose). Three small foci were visible only with the higher dose.

CONCLUSION

The higher dose of contrast material allowed much better results. Dose comparison studies are also recommended for other techniques.