- Color-Mapping of 4D-CTA for the Detection of Cranial Arteriovenous Shunts
A color-mapping method for 4D-CTA is presented for improved and enhanced visualization of the cerebral vasculature hemodynamics. This method was applied to detect cranial AVFs. Thirty-one patients were included, 21 patients with and 10 without an AVF. Arterialization of venous structures in AVFs was accurately visualized using color-mapping. There was high sensitivity (86%–100%) and moderate-to-high specificity (70%–100%) for the detection of AVFs on color-mapping 4D-CTA, even without the availability of dynamic subtraction rendering. Arterialization of venous structures can be visualized using color-mapping of 4D-CTA and proves to be accurate for the detection of cranial AVFs.
- Altered Relationship between Working Memory and Brain Microstructure after Mild Traumatic Brain Injury
The authors investigated how working memory deficits relate to detectable WM microstructural injuries to discover robust biomarkers that allow early identification of patients with mild traumatic brain injury at the highest risk of working memory impairment. Multi-shell diffusion MR imaging was performed on a 3T scanner with 5 b-values. Diffusion metrics of fractional anisotropy, diffusivity and kurtosis (mean, radial, axial), and WM tract integrity were calculated. Auditory-verbal working memory was assessed using the Wechsler Adult Intelligence Scale. ROI analysis found a significant positive correlation between axial kurtosis and Digit Span Backward in mild traumatic brain injury mainly present in the right superior longitudinal fasciculus, which was not observed in healthy controls.