Bullseye's representation of cerebral white matter hyperintensities

A Schmitt,A.F Mendelson,N Chaturvedi,H.R Jaeger,B Gomez Anson,F Prados,L Smith,I Davagnanam,F Barkhof,S Ourselin,D Atkinson,A.D Hughes,M.J Cardoso,C.H Sudre

doi:10.1016/j.neurad.2017.10.001

Abstract

Background and purposeVisual rating scales have limited capacities to depict the regional distribution of cerebral white matter hyperintensities (WMH). We present a regional-zonal volumetric analysis alongside a visualization tool to compare and deconstruct visual rating scales. Materials and methods3D T1-weighted, T2-weighted spin-echo and FLAIR images were acquired on a 3T system, from 82 elderly participants in a population-based study. Images were automatically segmented for WMH. Lobar boundaries and distance to ventricular surface were used to define white matter regions. Regional-zonal WMH loads were displayed using bullseye plots. Four raters assessed all images applying three scales. Correlations between visual scales and regional WMH as well as inter and intra-rater variability were assessed. A multinomial ordinal regression model was used to predict scores based on regional volumes and global WMH burdens. ResultsOn average, the bullseye plot depicted a right-left symmetry in the distribution and concentration of damage in the periventricular zone, especially in frontal regions. WMH loads correlated well with the average visual rating scores (e.g. Kendall's tau [Volume, Scheltens]=0.59 CI=[0.53 0.62]). Local correlations allowed comparison of loading patterns between scales and between raters. Regional measurements had more predictive power than global WMH burden (e.g. frontal caps prediction with local features: ICC=0.67 CI=[0.53 0.77], global volume=0.50 CI=[0.32 0.65], intra-rater=0.44 CI=[0.23 0.60]). ConclusionRegional-zonal representation of WMH burden highlights similarities and differences between visual rating scales and raters. The bullseye infographic tool provides a simple visual representation of regional lesion load that can be used for rater calibration and training.

Highlights

Material and methodsWhite manner hyperintensities (WMH) in the cerebral white matter on T2-weighted spin echo and fluid attenuated inversion recovery (FLAIR) magnetic resonance (MR) images are commonly part of the spectrum of imaging findings in cerebral small vessel disease and normal aging
The extracted total white matter hyperintensities (WMH) burden for the 82 subjects with available MR scans ranged from 0.38 mL to 25.28 mL
It illustrates the right-left symmetry as well as the prevalence of WMH in periventricular zones compared to deeper layers [30], the sparing of the Visual scale local deconstruction

Summary

Introduction

White manner hyperintensities (WMH) in the cerebral white matter on T2-weighted spin echo and FLAIR magnetic resonance (MR) images are commonly part of the spectrum of imaging findings in cerebral small vessel disease and normal aging. Their precise etiology is still a subject of debate and likely multifactorial [1]. The extent of WMH was recently shown to be an independent risk factor for periprocedural stroke in patients undergoing stenting of a carotid artery stenosis [7] and an indicator of prognostic outcome after ischemic stroke [8]

Results

Discussion

Conclusion