Objective To compare the similarities and differences between ultrasmall superparamagnetic iron oxide (US-PIO ) PWI and Cd-DTPA PWI , and to observe the feasibility of USPIO PWI in evaluating tumor angiogenesis . Methods C6 glioma model in 30 male rats were established and divided into two groups in random : USPIO PWI group and Cd-DTPA PWI group . Conventional M R imaging and PWI were performed at 12 days of tumor age . USPIO PWI and Gd-DTPA PWI were performed , respectively . Imaging sequences included SE T1W . FSE T2W . EPI PWI . ROIs at the largest section of tumor were selected in each rat . Perf'usion curves of tumors in enhancement areas and contralateral no rmal hrain tissue were obtained , and the maximum signal reduction ratio (SRRmax ) , regional blood volume (rBV ) and the ratio of' each parameter (QrBV , QSRR ) between the two ROIs were calculated . Histopathology examination was performed with HE staining and immunohistochemistry of GFAP . Results Statistical differences of the rBV and SSRma were f'ound between tumor tis -sue and normal brain tissue in both USPIO PWI and Gd-DTPA PWI group ( P＜ 0. 05 ) . The rBV and SSRmax in USPIO PWI group were higher than those in Gd-DTPA PWI group ( P＜ 0. 05 ) . Statistical diff'erence of the QrBV and QSRRmax were also found between the two groups ( P＜ 0. 05 ) . Conclusion USPIO PWI can demonstrate more ohvious perfusion effect than Gd-DTPA . therefore being helpful to the evaluation of tumor microcirculation .%目的 比较大鼠C6脑胶质瘤超小型超顺磁氧化铁(USPIO)PWI与Gd-DTPA PWI的异同点,观察USPIO PWI评价胶质瘤微血管水平血流灌注的可行性.方法 对30只雄性SD大鼠接种C6胶质瘤,并随机分成2组:USPIO PWI组及Gd-DTPA PWI组,于接种后12天行常规MR及PWI扫描,之后行SE T1W或FSE T2W增强扫描.于肿瘤最大层面选取ROI,分别于肿瘤强化区及对侧正常脑实质区获取灌注曲线,计算ROI的最大信号强度下降百分比(SRRmax)、相对血流容积(rBV)及肿瘤组织与正常脑组织rBV比值(QrBV)和SRRmax比值(QSRRmax),同时取肿瘤组织行HE及GFAP染色.结果 USPIO PWI组及Gd-DTPA PWI组肿瘤组织rBV和SRRmax值均明显高于对侧正常脑组织(P＜0.05).USPIO PWI组肿瘤组织rBV和SRRmax均高于Gd-DTPA PWI组(P＜0.05).USPIO PWI组与Gd-DTPA PWI组的肿瘤组织与正常脑组织QrBV和QSRRmax值之间差异有统计学意义(P＜0.05).结论 与 Gd-DTPA PWI相比, USPIO PWI具有更加明显的灌注效应,有助于评估肿瘤微循环.
展开▼
