MRI Texture Analysis and Diffusion Tensor Imaging in Chronic Right Hemisphere Ischemic Stroke

• Published in: Journal of neuroimaging 2015-07, Vol.25 (4), p.614-619
• Main Authors: Sikiö, Minna, Kölhi, Paula, Ryymin, Pertti, Eskola, Hannu J., Dastidar, Prasun
• Format: Article
• Language: English
• Subjects: Aged; Cerebral Infarction - complications; Cerebral Infarction - pathology; Chronic infarction; Diffusion; diffusion tensor imaging; Diffusion Tensor Imaging - methods; Female; Humans; Image Enhancement - methods; Image Interpretation, Computer-Assisted - methods; Imaging, Three-Dimensional - methods; magnetic resonance imaging; Male; Middle Aged; Neuroimaging; Reproducibility of Results; Sensitivity and Specificity; Stroke - etiology; Stroke - pathology; texture analysis
• ISSN: 1051-2284; 1552-6569
• DOI: 10.1111/jon.12185

ABSTRACT BACKGROUND AND PURPOSE Diffusion tensor imaging (DTI) is shown to reveal changes caused by cerebral infarction. The aim of this study is to reveal those changes also in the conventional magnetic resonance (MR) images using a quantitative image analysis method, texture analysis (TA). METHODS Thirty patients who had suffered their first ever infarction located on the right hemisphere underwent DTI and conventional MRI studies in the chronic phase. DTI parameters fractional anisotropy and mean diffusivity, as well as four second‐order texture parameters were calculated. Interhemispheric differences and correlations between DTI and TA parameters were evaluated. RESULTS Our DTI findings supported earlier studies as fractional anisotropy values were lowered and mean diffusivity values elevated in the lesion site, and ipsilateral cerebral peduncle, thalamus, and centrum semiovale compared to the unaffected side. Textural homogeneity parameters showed lower and complexity parameters higher values in the lesion site and ipsilateral centrum semiovale compared to the contralateral hemisphere. Correlation between the two methods was found in ipsilateral mesencephalon. CONCLUSIONS In addition to DTI method, TA could assist in revealing the changes caused by infarction, also outside the lesion site. Damaged areas were found more heterogeneous and random in texture compared to unaffected sites.