MR OF INTRACRANIAL TUMORS - COMBINED USE OF GADOLINIUM AND MAGNETIZATION-TRANSFER

PURPOSE: To study the potential combined application of gadolinium and magnetization transfer in the MR imaging of intracranial tumors. METH ODS: Twenty-two patients were imaged at low field strength (0.1 T). Co rresponding gradient-echo partial saturation images without and with m agnetization transfer pulse were produced. Images with intermediate re petition times were obtained in 18 cases; five different sequences wer e produced in 4 cases. Gadopentetate dimeglumine was used at a dose of 0.1 mmol/kg. RESULTS: Magnetization transfer effect increased the con trast between enhancing lesion and normal brain and the contrast betwe en edema and normal brain; the contrast between enhancing lesion and e dema was not significantly changed. On intermediate-repetition-time ma gnetization transfer images the contrast between enhancing tumor and n ormal brain and the contrast between edema and normal brain were super ior to short repetition-time magnetization transfer images, but the di fferentiation between enhancing tumor and edema was poorer. CONCLUSION : Magnetization transfer can be used to improve contrast in Gd-enhance d MR imaging. Combining magnetization transfer with an intermediate-re petition-time image provides the possibility for displaying both enhan cing and nonenhancing lesions on a single MR image.