GREY AND WHITE MATTER NETWORK DISRUPTION EXPLAINS THE EXTENT OF SOMATOSENSORY DEFICITS AFTER ISCHAEMIC STROKE BEYOND LESION VOLUME (ID 860)
Abstract
Background And Aims
Somatosensory deficits after ischaemic stroke are common and can occur in patients with cortical and subcortical lesions. It is less clear to what extent damage to white matter tracts within the somatosensory system contribute to post-stroke sensory deficits. We compared the impact of cortical damage and disruption of subcortical white matter tracts as correlates of somatosensory deficit after ischaemic stroke.
Methods
Clinical and imaging data were assessed in first-ever stroke patients. Somatosensory deficits were assessed with standardized somatosensory tests. Direct ischaemic damage to grey matter was computed by lesion overlap with predefined grey matter areas. Remote effects were calculated by projection of the MRI-based segmented stroke lesions onto a predefined atlas of white matter connectivity. The association between lesion impact scores and sensory deficit was assessed statistically.
Results
In 101 patients, median sensory score was 188/193 (97.4%). Lesion volume was associated with somatosensory deficit, explaining 23.3% of variance. Beyond this, the stroke-induced grey and white matter disruption explained an additional 14% of the somatosensory outcome variance within a subnetwork of the postcentral, supramarginal, and transverse temporal gyri. On mutual comparison, white matter network disruption was a stronger predictor than grey matter damage.
Conclusions
Ischaemic damage to both grey and white matter are structural correlates of acute post-stroke somatosensory deficits. The data implicate that white matter integrity of a somatosensory network of primary and secondary cortex is a prerequisite for normal processing of somatosensory inputs and might be considered as an additional parameter for stroke outcome prediction in the future.
Trial Registration Number
Not applicable
