Blair Winegar | Searcharxiv

arXiv2020

White matter hyperintensities volume and cognition: Assessment of a deep learning based lesion detection and quantification algorithm on the Alzheimers Disease Neuroimaging Initiative

The relationship between cognition and white matter hyperintensities (WMH) volumes often depends on the accuracy of the lesion segmentation algorithm used. As such, accurate detection and quantification of WMH is of great interest. Here, we use a deep learning-based WMH segmentation algorithm, StackGen-Net, to detect and quantify WMH on 3D FLAIR volumes from ADNI. We used a subset of subjects (n=20) and obtained manual WMH segmentations by an experienced neuro-radiologist to demonstrate the accuracy of our algorithm. On a larger cohort of subjects (n=290), we observed that larger WMH volumes correlated with worse performance on executive function (P=.004), memory (P=.01), and language (P=.005).

eess.IV↗

arXiv2019

T2-weighted Spine Imaging using a Single-Shot Turbo Spin Echo Pulse Sequence

T2 weighted imaging of the spine is commonly performed using fast spin echo (FSE/TSE) based sequences, resulting in long scan times and vulnerability to motion artifacts. While single shot fast spin echo sequences have been attempted, their adoption has been limited by poor spatial resolution and specific absorption rate (SAR) limitations. We investigate the use of a half-Fourier acquisition single-shot turbo spin-echo variable flip angle (HASTE-VFA) sequence for T2 weighted spine imaging. A variable refocusing flip angle echo train was first optimized for the spine to improve the point spread function (PSF) and minimize SAR, yielding images with improved spatial resolution and signal-to-noise ratio compared to the constant flip angle sequence. Data was acquired from 29 patients (20 lumbar and thoracolumbar, 9 whole-spine) using conventional fast spin echo and the proposed variable flip angle single-shot sequences. All images were graded by two experienced neuroradiologists in a blinded fashion and scores were assigned based on blurring, motion, artifacts, and noise as well as appearance of disks, facet joints, end plates, nerve roots and the spinal cord.

physics.med-ph↗