CAJ | 학술논문

目的探讨弥散张量成像(DTI)中不同数目的梯度方向对成人脑组织各向异性分数(FA)的离散程度及其信噪比(SNR)的影响.方法应用7种不同弥散梯度方向数目(NDGD)对8名健康志愿者脑组织进行DTI扫描并获取FA图,计算FA图中4个感兴趣区(ROI)(胼胝体膝部、胼胝体压部、内囊膝部、内囊后肢)的FA值及其SNR,分析其随NDGD增加的变化趋势.结果脑内各个ROI的FA值不随NDGD的增加而显著变化;信号强的ROI(胼胝体膝部、胼胝体压部)内FA值方差随机波动,其SNR增加不大;信号弱的ROI(内囊膝部、内囊后肢)内FA值方差随着NDGD的增加而逐渐减小.结论在DTI的临床应用中,要根据检查的部位选择最适宜的NDGD.
목적 탐토미산장량성상(DTI)중불동수목적제도방향대성인뇌조직각향이성분수(FA)적리산정도급기신조비(SNR)적영향.방법 응용7충불동미산제도방향수목(NDGD)대8명건강지원자뇌조직진행DTI소묘병획취FA도,계산FA도중4개감흥취구(ROI)(변지체슬부、변지체압부、내낭슬부、내낭후지)적FA치급기SNR,분석기수NDGD증가적변화추세.결과 뇌내각개ROI적FA치불수NDGD적증가이현저변화;신호강적ROI(변지체슬부、변지체압부)내FA치방차수궤파동,기SNR증가불대;신호약적ROI(내낭슬부、내낭후지)내FA치방차수착NDGD적증가이축점감소.결론 재DTI적림상응용중,요근거검사적부위선택최괄의적NDGD.
Objective To assess the impact of different number of diffusion gradient directions (NDGD) of diffusion tensor imaging (DTI) on dispersion degree of fractional anisotropy (FA) values and signal-to-noise ratio (SNR) for adult brain tissues. Methods Eight healthy volunteers underwent DTI with 7 NDGD respectively, and the associated FA maps were obtained. Four region of interest (ROI) (genu and splenial of corpus callosum, genu and posterior limb of internal capsule) were chosen in white matter of FA maps, FA values and the corresponding SNRs of the ROIs were computed and analyzed with NDGD increasing. Results FA values within all ROIs did not change remarkably with NDGD increasing. Variance of FA value within two ROIs with high gray value (genu and splenial of corpus callosum) fluctuated randomly and SNR increased slightly, while variance of FA value within the ROIs with low gray value (genu and posterior limb of internal capsule) diminished significantly with NDGD increasing. Conclusion In clinical applications of DTI, an optimum NDGD for DTI data acquisition should be selected according to the ROIs in human brain to be inspected.