Single Subcortical Infarct: Pathomechanism Assessed by Thin-Section Computed Tomography Perfusion

Area of Science:

• Neurology
• Radiology
• Medical Imaging

Background:

• Understanding the pathomechanism of single subcortical infarcts (SSI) is crucial for effective treatment.
• Assessing the perfusion status between the parent artery and the ischemic lesion can provide insights into SSI development.
• Branch atheromatous disease (BAD) is a potential cause of SSI, but its accurate classification is challenging.

Purpose of the Study:

• To compare the classification of BAD in SSI using diffusion-weighted imaging (DWI) versus computed tomography perfusion (CTP).
• To evaluate whether a CTP-based classification improves the prediction of progression in SSI (PSSI) compared to DWI.
• To identify predictors for PSSI in patients with SSI.

Main Methods:

• 109 patients with SSI underwent CTP and follow-up DWI.
• Branch atheromatous disease (BAD) was defined based on DWI criteria or CTP-derived time-to-drain (TTD) maps and proximity to cerebrospinal fluid perforators.
• Demographics, imaging findings, and PSSI rates were compared between BAD and non-BAD groups classified by CTP.
• Multivariable regression analysis identified predictors for PSSI.

Main Results:

• CTP classified significantly fewer patients as BAD (29.4%) compared to DWI (60.6%).
• Progression in SSI (PSSI) was significantly higher in the BAD group (40.6%) compared to the non-BAD group (11.7%) when classified by CTP (P=.002).
• DWI-based classification did not show a significant difference in PSSI between BAD and non-BAD groups (P=.930).
• BAD-type perfusion identified by CTP was the sole independent predictor for PSSI (OR, 5.209; P=.003).

Conclusions:

• Classifications of SSI with and without BAD differ significantly between CTP and DWI.
• CTP provides a more accurate assessment of BAD in SSI.
• CTP-based classification of BAD is a valuable tool for predicting PSSI.