The Usefulness of Thin-section Iso-Voxel Diffusion Weighted Imaging for Stroke Subtype Classification: Case Series and Review.

Abstract Background: Determining stroke subtypes on initial clinical evaluation is a prerequisite for the selection of appropriate initial treatment. Although diffusion-weighted imaging (DWI) is a powerful tool for detection of acute cerebral infarction, its diagnostic accuracy is not always sufficient particularly in the hyperacute phase. Methods: Patients admitted within 2 weeks from the symptom onset with the diagnosis of acute ischemic strokes were analyzed with thin-section iso-voxel DWI, namely 3-dimension DWI (3D-DWI), to obtain axial, coronal, and sagittal sections in order to elucidate stroke characteristics. In this case series, we introduce the effectiveness of 3D-DWI. Results: 3D-DWI uncovered stroke subtypes and distribution more precisely compared with conventional DWI. While previous studies indicated the utility of thin section DWI in detecting infratentrial infarctions, 3D-DWI is beneficial for the detection of not only infratentrial but also supratentorial lesions. Furthermore, since both 3D-DWI and magnetic resonance angiography (MRA) are multiplanar reconstruction images, the fusion image of 3D-DWI with MRA is available, enabling cross-reference of spatial cerebrovascular configuration and ischemic lesions. Conclusions: 3D-DWI is applicable to standard 1.5 T MRI by slight modification of data acquisition protocols, and becomes a key modality to solve the diagnostic puzzle of acute ischemic strokes.