G03 Corpus callosal atrophy in Huntington's disease

Abstract

<h3>Background</h3> Research into Huntington9s disease (HD) has revealed white-matter loss in individuals more than 10 years prior to predicted disease onset, focused around the striatum, corpus callosum (CC) and posterior white-matter tracts. Degeneration of the CC is of interest since it provides interhemispheric connections to cortical areas known to be affected in HD. <h3>Aims</h3> This study aims to investigate the utility of volumetric measurements of the CC in HD using a novel segmentation technique, multiple time-points and a large well-characterised cohort. Structure-function relationship in the CC will also be explored. <h3>Methods</h3> Volumetric 3T MRI from controls, premanifest gene carriers and early HD subjects enrolled in the TRACK-HD study will be analysed at baseline and 24 months. The CC will be delineated using a semi-automated segmentation protocol. Differences in baseline volumes and atrophy rates between groups will be examined, as well as correlations between volume loss and clinical impairment. <h3>Results</h3> Preliminary analysis of a subset of subjects indicates that early HD subjects have reduced CC volume compared with controls and premanifest subjects (p&lt;0.001). Increased longitudinal CC volume change was found in early HD subjects, compared with controls (p&lt;0.001). Interestingly there was significant difference in longitudinal change between controls and premanifest subjects close to disease onset (p&lt;0.05). This work will be extended to include multi-site data and correlations between atrophy and clinical and cognitive decline. <h3>Conclusions</h3> Measurement of CC atrophy may have potential as an imaging biomarker for HD and may prove useful for exploring interhemispheric structure-function relationships. <h3>Funding</h3> Helen Crawford is supported by the CHDI Foundation, a not for profit organisation dedicated to finding treatments for HD.