Boonrod Arunnit, Hagiwara Akifumi, Hori Masaaki, Fukunaga Issei, Andica Christina, Maekawa Tomoko, Aoki Shigeki
Department of Radiology, Juntendo University School of Medicine, 1-2-1, Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
Department of Radiology, Khon Kaen University, 123 Mittraparp Rd, Khon Kaen, 40002, Thailand.
Neuroradiology. 2018 Sep;60(9):979-982. doi: 10.1007/s00234-018-2065-6. Epub 2018 Jul 26.
Diffusion-weighted imaging (DWI) is a useful tool for early detection of cerebral infarction. However, recent reports have demonstrated that DWI with short effective diffusion time (∆) can obscure visualization of infarction.
We report three cases, including four acute-to-subacute infarctions, that demonstrated reduced visualization of the infarctions on DWI with shorter ∆.
DWI was performed with different ∆: short and long ∆, using oscillating gradient spin-echo (OGSE) DWI, and intermediate ∆, using pulsed gradient spin-echo (PGSE) DWI. Different apparent diffusion coefficient values (due to different ∆) were also observed; these were considered to be the underlying causes of the under-evaluation of infarctions on DWI.
The DWI with shorter ∆ may obscure infarction. High-performance magnetic resonance imaging scanners with higher maximal gradient strength (G) can perform DWI with shorter ∆ than scanners with lower G. Therefore, the appropriate ∆ should be set for the detection of restricted diffusion.
扩散加权成像（DWI）是早期检测脑梗死的有用工具。然而，最近的报告表明，有效扩散时间（∆）较短的DWI可能会掩盖梗死灶的显示。
我们报告了3例病例，包括4个急性至亚急性梗死灶，这些病例显示在∆较短的DWI上梗死灶的显示减少。
使用振荡梯度自旋回波（OGSE）DWI以不同的∆（短∆和长∆）进行DWI，并使用脉冲梯度自旋回波（PGSE）DWI以中等∆进行DWI。还观察到不同的表观扩散系数值（由于∆不同）；这些被认为是DWI上梗死灶评估不足的根本原因。
∆较短的DWI可能会掩盖梗死灶。最大梯度强度（G）较高的高性能磁共振成像扫描仪比G较低的扫描仪能够以更短的∆进行DWI。因此，应设置适当的∆以检测扩散受限。
