Table 5.
Studies assessing the diagnostic accuracy of CT perfusion in patients with lacunar stroke or confirmed RSSI.
| Reference | Population | Perfusion Maps | Main Findings |
|---|---|---|---|
| Rudilosso, 2015 [43] | A total of 33 patients with lacunar syndrome (16 lacunar strokes, 13 non-lacunar strokes, and 4 no ischemic lesions). Lacunar stroke defined as infarct volume <1.767 cm3 (the volume of a sphere with a diameter 1.5 cm) on DWI. |
Postprocessing software: CT Neuro Perfusion Syngo.via (Siemens Healthcare GmbH) for visual assessment. MIStar (Apollo Medical Imaging Technology, Melbourne, Australia) for core/penumbra threshold analysis. Perfusion maps: CBF, CBV, MTT, Tmax, TTP, TTD, and MIP. |
SE and PPV for lacunar stroke higher than non-contrast CT (63% vs. 19%). CTP was more sensitive for supratentorial lesions, compared with infratentorial lesions (65% versus 16%). SP was low (20%) and influenced by low lacunar stroke prevalence. TTD was the most informative map for the identification of ischemic lesions. |
| Das, 2015 [163] | A total of 88 patients with lacunar syndrome (after excluding stroke mimics). RSSI: 59/88 (67%). | Postprocessing software: GE Healthcare Perfusion maps: CBV, CBF, and MTT. |
SE56%, SP 83%. CTP increased the diagnostic performance 5-fold over non-contrast CT. MTT were the most informative maps to identify RSSI. |
| Benson, 2016 [164] | A total of 113 patients: 37 with ischemic lesions on DWI < 20 mm in maximum diameter (either cortical or subcortical) and 76 without ischemic lesions. Ischemic lesions > 20 mm, and patients treated with iv tPA were excluded from the analysis. | Postprocessing software: Vitrea workstation (Vital Imaged, Minnetonka, Minnesota) Perfusion maps: TTP, MTT, CBV, and CBF. |
TTP were the maps with highest SE (49%), and lowest for non-contrast CT (3%). SP was high regardless the map evaluated (all >97%). The perfusion lesions on CTP appeared larger than the lesion on DWI. |
| Tan, 2016 [161] | A total of 182 patients with ischemic strokes (31 single subcortical, 9 multiple subcortical, 34 cortical only, 33 non-confluent cortical-subcortical, and 75 confluent cortical-subcortical). | Postprocessing software: Advantage Windows (GE Medical Systems) and Extended Brilliance Workspace (Philips Healthcare, Best, Netherlands) Perfusion maps: MTT. |
39% of the RSSI (single subcortical) on DWI had a perfusion deficit. However, for 67% of them, the perfusion deficit was larger than the DWI lesion and were associated with a large vessel occlusion on CT angiography. |
| Cao, 2016 [165] | A total of 62 patients: 32 with RSSI and 30 without lesions on DWI. | Postprocessing software: RAPID iSchemicView (Menlo Park, CA, US) Perfusion maps: CBF, CBV, MTT, and Tmax. |
MTT showed 56% SE. No false positive perfusion images were rated. |
| García-Esperón, 2021 [166] | A total of 106 patients with lacunar syndrome: RSSI, 33 cortical and 14 posterior fossa strokes. Patients without lesions on DWI were excluded. | Postprocessing software: MIStar (Apollo Medical Imaging Technology, Melbourne, Australia) Perfusion maps: CBF, CBV, MTT, and DT. |
42% SE, 80% SP for RSSI. Visual inspection of CTP maps had higher SE than the automated method (42% vs. 6%). Sensitivity on non-contrast CT was very low (<4%). |
CBF: cerebral blood flow; CBV: cerebral blood volume; CTP: CT perfusion; DT: delay time; DWI: diffusion-weighted imaging; MIP: maximum intensity projection; MTT: mean transient time; PPV: positive predictive value; RSSI: recent small subcortical infarct; SE: sensitivity; SP: specificity; Tmax: time to maximum; TTD: time to drain; TTP: time to peak.