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RT Journal Article
SR Electronic
T1 Blood Volume of Gliomas Determined by Double-Echo Dynamic Perfusion-Weighted MR Imaging: A Preliminary Study
JF American Journal of Neuroradiology
JO Am. J. Neuroradiol.
FD American Society of Neuroradiology
SP 1915
OP 1919
VO 22
IS 10
A1 Uematsu, Hidemasa
A1 Maeda, Masayuki
A1 Sadato, Norihiro
A1 Matsuda, Tsuyoshi
A1 Ishimori, Yoshiyuki
A1 Koshimoto, Yoshio
A1 Kimura, Hirohiko
A1 Yamada, Hiroki
A1 Kawamura, Yasutaka
A1 Yonekura, Yoshiharu
A1 Itoh, Harumi
YR 2001
UL http://www.ajnr.org/content/22/10/1915.abstract
AB BACKGROUND AND PURPOSE: After bolus injection, gadopentetate dimeglumine causes a T2* rate change in permeable tissue that is contaminated by the T1 shortening effect due to the leakage of contrast agent. Therefore, tumor vascularity as reported in previous single-echo perfusion-weighted MR imaging studies has been underestimated. Our aim was to quantitatively and qualitatively evaluate the degree of blood volume of glioblastoma multiformes (GBMs) underestimated by this T1 shortening effect.METHODS: We used double-echo dynamic MR imaging after a bolus injection of gadopentetate dimeglumine (double-echo perfusion-weighted MR imaging) to simultaneously determine tumor blood volume without (VT1U) and with (VT1C) T1 shortening correction. MR imaging was performed in five consecutive patients with GBMs. The ratios of VT1U and VT1C were calculated and compared by means of quantitative analysis. The degree of tumor blood volume as determined by VT1U and VT1C maps were qualitatively compared using a three-point scale.RESULTS: All GBMs showed contrast enhancement on postcontrast T1-weighted images. In all subjects, the values of VT1U were significantly lower than those of VT1C (mean ± SD, 2.05 ± 1.01 vs. 3.62 ± 1.40, respectively [P &lt; .05]), indicating that tumor blood volume obtained by double-echo perfusion-weighted MR imaging was significantly higher than that by single-echo imaging. In the qualitative analysis, tumor blood volume on the VT1U map was less conspicuous than that on the VT1C map.CONCLUSION: Careful attention should be paid to the underestimation of tumor blood volume resulting from T1 shortening effects when using single-echo perfusion-weighted MR imaging. Double-echo imaging may be more suitable for the analysis of blood volume in GBMs.