PREMOTOR CORTEX STROKE VOLUME MAY AID BETTER PREDICTION OF EATING OUTCOMES COMPARED WITH TOTAL STROKE VOLUME IN ACUTE STROKE

The premotor cortex (PMC) coordinates reaching, grasping, and eating-related actions. Whether PMC stroke volume affects eating outcomes more than total infarct volume remains unclear. This study aimed to compare the associations of PMC stroke volume and total stroke volume with eating actions within the same patients with acute stroke involving PMC. We retrospectively analyzed 17 patients with acute PMC infarction. Eating outcomes were evaluated using the Functional Independence Measure (FIM) score (1-7) within 4 weeks post-stroke. PMC and total stroke volumes were manually measured on MRI images. Ordinal logistic regression assessed the associations of PMC and total stroke volumes with FIM eating score. Odds ratios (ORs) were reported, proportional-odds assumptions were checked (Brant test). Furthermore, poor eating outcome (FIM ≤4) discrimination between PMC and total stroke volume was evaluated using ROC analysis, estimating the area under the curve (AUC) and AUC differences (DeLong test). The proportional-odds assumption was satisfied (Brant: PMC p=1.00; total p=0.79). Ordinal logistic regression indicated larger PMC stroke volume was significantly associated with poorer FIM eating (OR 485.5; p=0.039); per 10% increase, OR 1.86 (95% CI 1.03–3.34). Conversely, total stroke volume showed no significant association with FIM eating scores (p=0.176). PMC stroke volume showed higher discrimination for poor eating outcome (AUC 0.843; 95% CI 0.565–1.000) than total stroke volume (AUC 0.657; 95% CI 0.360–0.954), with a trend favoring PMC (DeLong p=0.099). A larger normalized PMC stroke volume was linked to poorer eating outcomes and provided better outcome discrimination, supporting regional specificity of PMC involvement.