Contrast-Enhanced Turbo Spin-Echo(TSE) T1-weighted Imaging: Improved Contrast of Enhancing Lesions

ABSTRACT

PURPOSE: The purpose of this study was to evaluate the effect of contrast improvement of enhancing brain lesions by inherent magnetization transfer effect in turbo spin-echo (TSE) T1-weighted MR imaging. MATERIALS AND METHODS: Twenty-six enhancing lesions of 19 patients were included in this study. Using a 1.0T superconductive MR unit, contrast-enhanced SE T1-weighted images (TR=600 msec, TE=12 msec, NEX=2, acquisition time=4 min 27sec) and contrast-enhanced TSE T1-weighted images (TR=600 msec, TE=12 msec, NEX=2, acquisition time=1min 44sec) were obtained. Signal intensities at enhancing lesions and adjacent white matter were measured in the same regions of both images. Signal-to-noise ratio (SNR) of enhancing lesions and adjacent white matter, and contrast-to-noise ratio (CNR) and lesion-to-background contrast (LBC) of enhancing lesions were calculated and statistically analysed using the paired t-test. RESULTS: On contrast-enhanced TSE T1-weighted images, SNR of enhancing lesions and adjacent white matter decreased by 18%(p<0.01) and 32% (p<0.01), respectively, compared to contrast-enhanced SET1-weighted images. CNR and LBC of enhancing lesions increased by 16% (p<0.05) and 66% (p<0.01), respectively. CONCLUSION: Due to the proposed inherent magnetization transfer effects in TSE imaging, contrast-enhanced T1-weighted TSE images demonstrated a statistically significant improvement in CNR and LBC, compared to conventional contrast-enhanced T1-weighted SE images, and scan time was much shorter.