The value of b0 images obtained from diffusion-weighted echo planar sequences for the detection of intracranial hemorrhage compared with GRE sequence

AbstractPurposeOur aim was to evaluate the clinical utility of b0EPI images obtained from diffusion sequence for the detection of the intracranial hemorrhagic lesions, especially acute intracerebral bleeds thereby shorten the scan time particularly in the critical acute cases of stroke.Materials and methodsAmong all consecutive MR brain studies performed in our department last year, we retrospectively selected those who followed the following criteria: (1) clinically suspected or radiographically confirmed acute infarction or hemorrhage. (2) MRI imaging including DWI and T2∗ images. Sensitivity of hemorrhage detection, conspicuity of lesions, and diagnostic certainty were compared between the b0EPI and GRE sequences.ResultsThere were 77 hemorrhagic lesions with a variety of pathogeneses in various locations. 76/77 (98.7%) of these lesions were hemorrhagic (hypointense) on the GRE sequences, whereas 61 (79.2%) were characterized as hemorrhagic on b0EPI images, and 16 (20.8%) were not detected. The overall difference in hemorrhage conspicuity/diagnostic certainty between GRE and b0EPI sequences was statistically significant (P<.05).Conclusionb0EPI sequence, although shorter in acquisition time, was inferior to GRE imaging in the detection of acute and chronic intracerebral hemorrhage

Correlation of diffusion tensor imaging findings and episodic memory impairment in temporal lobe epilepsy

Purpose: Our aim was to evaluate the utility of diffusion tensor imaging (DTI) in exploration of white matter tracts microstructure changes and clarify their relation to episodic memory in temporal lobe epilepsy (TLE). Materials and methods: DTI was performed on 30 (18 left, 12 right) TLE patients and 20 healthy controls. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) were calculated for six fiber tracts; the parahippocampal cingulum (PHC), superior longitudinal fasciculus (SLF), inferior longitudinal fasciculus (ILF), fornix (FORX), uncinate fasciculus (UF) and corpus callosum (CC). Assessment for episodic memory (visual and verbal) was performed at least 48 h after the last seizure. Results: All TLE patients had episodic memory impairment. Left TLE patients demonstrated more verbal memory affection, whereas right TLE patients demonstrated more visual memory affection (p < 0.05). Abnormal DTI parameters (decreased FA and increased ADC) were detected in most of the white matter tracts (p < 0.001) compared to control group. In left TLE patients, there was significant correlation between DTI parameters of left (PHC, SLF, UF, FORX) and verbal memory. Whereas, in right TLE patient, we found significant correlation between DTI parameters of right ILF and visual memory. Conclusions: TLE patients had multiple micro-structural white matter tracts abnormalities and episodic memory impairment. Both are structurally and functionally related