Purpose: To quantitatively measure the degree of contrast enhancement of central nervous system (CNS) tumor, infection, and infarction by means of magnetization transfer (MT) magnetic resonance (MR) imaging.
Materials and methods: T1-weighted MR images obtained before and after administration of contrast material with and without MT in 14 patients with CNS tumors were evaluated by means of a contrast-to-noise ratio (C/N). Another 72 patients with a variety of lesions underwent contrast material-enhanced T1-weighted MR imaging prospectively with and without MT; C/N was also evaluated.
Results: All lesions had a higher C/N on T1-weighted postcontrast MT images than on conventional images. C/N was 65 +/- 5 (mean +/- standard error) for MT and 42 +/- 4 for conventional images. C/N improved by a factor of 1.6-2.1 in the three disease categories. In intracranial tumors, the MT technique itself did not contribute significantly (P < .001) to the increase in C/N in the absence of gadopentetate dimeglumine. In fact, the C/N was lower for nonenhanced T1-weighted MT images.
Conclusion: Concurrent use of gadopentetate dimeglumine and MT results in a statistically significant (P < .001) increase in C/N in CNS tumor, infection, and infarction.