Abstract Number: Esoc2026a858 Inferior Frontal Sulcal Hyperintensities on Magnetic Resonance Imaging in Sporadic Cerebral Small Vessel Disease: A Longitudinal Study

Abstract Background and aims Inferior frontal sulcal hyperintensities (IFSH) on MRI (Figure-1) may be a non-invasive biomarker of altered cerebrospinal fluid (CSF) waste clearance. We assessed the relationships of baseline IFSH with baseline and one-year small vessel disease (SVD) neuroimaging features and cognition. Methods We recruited patients with mild stroke (Mild Stroke Study-3: ISRCTN 12113543). We acquired baseline and one-year 3T MRI to assess brain volume, white matter hyperintensity (WMH) and perivascular space volumes, IFSH using an established visual rating scale and cognition using Montreal Cognitive Assessment. We ran multivariable linear regressions between baseline IFSH score and baseline or one-year SVD features and cognition adjusting for age, sex and vascular risk factors (and baseline value in longitudinal analyses), categorizing one-year WMH volume change into quintiles: Q1 (most regression), Q3 (stable), Q5 (most progression). We tested between-group differences in baseline IFSH score using Kruskal-Wallis test with post-hoc Dunn tests. Results Amongst 226 patients (mean age 66, SD 11; 66% male), participants with higher baseline IFSH score had lower baseline brain volume (B=-0.292, 95% confidence interval (95%CI)=-0.570 to -0.013) but no relation to baseline or one-year SVD features or cognition (Figure-2). However, IFSH scores differed across WMH volume change quintiles (Kruskal-Wallis p=0.036; Figure-3) with significantly higher IFSH scores in the highest WMH progression compared with the middle quintile. Conclusions Higher baseline IFSH scores, indicating more CSF debris, were associated with greater WMH progression, perhaps suggesting that impaired brain waste clearance increases future WMH progression risk, and providing a risk-prediction marker. Conflict of interest All authors declare no competing interests directly related to this study. Figure 1 - belongs to Background and aims Figure 2 - belongs to Results Figure 3 - belongs to Conclusions