高b值及超高b值扩散加权磁共振成像在脑卒中中的应用

High b-Value and Ultra-High b-Value Diffusion Weighted MRI in Stroke.

作者信息

Jiang Rifeng, Wang ZhenXiong, Liu Jun, Li Ting, Lv YanChun, Xie Chuanmiao, Su Changliang

机构信息

Department of Radiology, Fujian Medical University Union Hospital, Fuzhou, China.

Department of Radiology, Guangzhou First People's Hospital, School of Medicine, South China University of Technology, Guangzhou, China.

出版信息

J Magn Reson Imaging. 2025 Mar;61(3):1459-1469. doi: 10.1002/jmri.29547. Epub 2024 Jul 29.

DOI:10.1002/jmri.29547

PMID:39074845

Abstract

PURPOSE

To explore the application value of high-b-value and ultra-high b-value DWI in noninvasive evaluation of ischemic infarctions.

STUDY TYPE

Prospective.

SUBJECTS

Sixty-four patients with clinically diagnosed ischemic lesions based on symptoms and DWI.

FIELD STRENGTH/SEQUENCE: 3.0 T/T2-weighted fast spin-echo, fluid-attenuated inversion recovery, pre-contrast T1-weighted magnetization prepared rapid gradient echo sequence, multi-b-value trace DWI and q-space sampling sequences.

ASSESSMENT

Lesions were segmented on standard b-value DWI (SB-DWI, 1000 s/mm), high b-value DWI (HB-DWI, 4000 s/mm) and ultra-high b-value DWI (UB-DWI, 10,000 s/mm), and cumulative segmented areas were the final abnormality volumes. Normal white matter (WM) areas were obtained after binarization of segmented brain. In 47 patients, fractional anisotropy (FA) and apparent diffusion coefficients (ADCs) at b values of 1000, 4000, and 10,000 s/mm were extracted from symmetrical WM masks and lesion masks of contralateral WM (CWM) and lesion-side WM (LWM).

STATISTICAL TESTS

Wilcoxon matched-pairs signed-rank test and Pearson correlation analysis. Two-tailed P-values <0.05 were considered statistically significant.

RESULTS

Various signals of HB-/UB-DWI (hypo-, iso- or hyper-intensity) were observed in strokes compared with SB-DWI, and some areas with iso-intensity of SB-DWI manifested with hyper-intensity on HB-/UB-DWI. Abnormality volumes from SB-DWI were significantly smaller than those from HB-DWI and UB-DWI (10.32 ± 16.45 cm, vs. 12.25 ± 19.71 cm and 11.83 ± 19.41 cm), while no significant difference exist in volume between HB-DWI and UB-DWI (P = 0.32). In CWM, FA significantly correlated with ADC and ADC (maximum r = -0.51 and -0.64), but did not significantly correlate with ADC (maximum r = -0.20, P = 0.17). ADC or ADC of LWM not significant correlated with FA of CWM (maximum r = -0.28, P = 0.06), while ADC of LWM significantly correlated with FA of CWM (maximum r = -0.46).

DATA CONCLUSION

HB- and UB-DWI have potential to be supplementary tools for the noninvasive evaluation of stroke lesions in clinics.

EVIDENCE LEVEL

2 TECHNICAL EFFICACY: Stage 2.

摘要

目的

探讨高b值及超高b值扩散加权成像（DWI）在缺血性梗死无创评估中的应用价值。

研究类型

前瞻性研究。

研究对象

64例基于症状及DWI临床诊断为缺血性病变的患者。

场强/序列：3.0T/T2加权快速自旋回波序列、液体衰减反转恢复序列、对比剂前T1加权磁化准备快速梯度回波序列、多b值追踪DWI及q空间采样序列。

评估

在标准b值DWI（SB-DWI，1000s/mm²）、高b值DWI（HB-DWI，4000s/mm²）及超高b值DWI（UB-DWI，10000s/mm²）上对病变进行分割，累积分割面积即为最终异常体积。对分割后的脑图像进行二值化处理后获得正常白质（WM）区域。在47例患者中，从对侧WM（CWM）及病变侧WM（LWM）的对称WM模板及病变模板中提取b值为1000、4000及10000s/mm²时的分数各向异性（FA）及表观扩散系数（ADC）。

统计学检验

Wilcoxon配对符号秩检验及Pearson相关分析。双侧P值<0.05被认为具有统计学意义。

结果

与SB-DWI相比，在卒中患者中观察到HB-/UB-DWI的各种信号（低、等或高信号），且一些SB-DWI呈等信号的区域在HB-/UB-DWI上呈高信号。SB-DWI的异常体积显著小于HB-DWI及UB-DWI（10.32±16.45cm³ vs. 12.25±19.71cm³及11.83±19.41cm³），而HB-DWI与UB-DWI之间的体积无显著差异（P = 0.32）。在CWM中，FA与ADC及ADC显著相关（最大r = -0.51及-0.64），但与ADC无显著相关性（最大r = -0.20，P = 0.17）。LWM的ADC或ADC与CWM的FA无显著相关性（最大r = -0.28，P = 0.06），而LWM的ADC与CWM的FA显著相关（最大r = -0.46）。