Search Results (14)

Background/Objectives: Rheumatoid arthritis (RA) has been associated with accelerated atherosclerosis and cerebrovascular alterations. Our 2017 study compared 60 RA patients to healthy controls, assessing vascular, neurological, and cognitive parameters. The present study is a follow-up of these RA patients to evaluate disease progression and vascular changes over time, using their 2017 results as baseline. Methods: In 2023, we reassessed 43 of the original 60 RA patients using laboratory testing, carotid ultrasound, functional transcranial Doppler (TCD) and brain magnetic resonance imaging (MRI) examinations. Changes over time were analyzed within the same individuals. Results: Inflammatory markers and lipid profiles showed a trend toward improvement, though changes were not statistically significant, except for a significant increase in vitamin D (p < 0.001) and a decrease in Disease Activity Score in 28 Joints (DAS28) scores (p < 0.001). Carotid ultrasound revealed a significant increase in plaque burden (p = 0.022 on the right side and p = 0.008 on the left), while carotid intima media thickness (cIMT) showed a non-significant rise. TCD measurements indicated significantly increased pulsatility (p < 0.001 on the right, p = 0.001 on the left side) and resistance (p = 0.001 on the right, p = 0.012 on the left side) indices and reduced flow velocities (p < 0.001 on the right and p = 0.001 on the left side) in bilateral middle cerebral arteries (MCAs). The cerebrovascular reserve capacity was significantly lower on the right side overall (p = 0.013), with further decline noted in the methotrexate (MTX)-treated subgroup on the left side (p = 0.043). MRI findings showed non-significant numerical trends toward worsening lacunar small-vessel disease (p = 0.405) and cerebral atrophy (p = 0.063), with higher but stable lacunar infarction scores among MTX users (p = 0.023). Conclusions: Despite improved inflammatory control, RA patients demonstrated progressive vascular and hemodynamic alterations over time, while MRI changes should be interpreted as trends. These findings support multimodal vascular monitoring in RA. Full article

Objectives: In patients presenting to the emergency department with acute ischemic stroke (AIS), there is a growing need for practical and rapid biomarkers that can effectively predict prognosis and infarct volume, complementing neurological examination and imaging methods. Methods: This study retrospectively evaluates patients diagnosed with AIS at the emergency department of Bilecik Training and Research Hospital between 1 March 2022, and 30 September 2023. Patients who were transferred for reperfusion therapy were excluded, as thrombolysis and mechanical thrombectomy were not available at our institution during the study period. The systemic immune–inflammation index (SII) and the systemic inflammation response index (SIRI) scores were calculated based on patients’ laboratory values. Additionally, infarct volumes were independently assessed by two experienced radiologists and calculated by multiplying the hyperintense areas on diffusion-weighted magnetic resonance imaging by slice thickness. Results: Of the 349 patients diagnosed with AIS during this study period, 257 who met the inclusion criteria were analyzed. The median age was 76 years (IQR: 66–83), and 130 (51%) patients were female. Lacunar infarction was present in 109 patients (42.4%), while 148 (57.6%) had non-lacunar infarction. The all-cause mortality rates at 1 month, 1 year, and 2 years were 7.8%, 21.4%, and 29.6%, respectively. SII and SIRI scores were significantly higher in deceased patients compared to survivors across all time points for mortality. Conclusions: The findings of this study suggest that SII and SIRI values, derived from complete blood count parameters, may contribute to the early identification and management of high-risk AIS patients. Full article

Peripheral artery disease (PAD) is found in 10.9% of patients with ischaemic stroke (IS). This cross-sectional study was performed to investigate the prevalence of PAD and its risk factors among acute IS patients in Singapore. Patients admitted for IS were recruited. Data was collected on sex, age, body mass index (BMI), history of hypertension, diabetes mellitus (DM), hypercholesterolaemia, cigarette smoking, prior stroke (PS) and ischaemic heart disease (IHD). IS was classified as a lacunar infarct (LI) or non-lacunar infarct (NLI) based on neuroimaging. Carotid intima–medial thickening (IMT) and carotid plaques (CP) were determined by ultrasonography. The ankle–brachial Index (ABI) was calculated in both lower limbs; PAD was diagnosed if the ABI was ≤0.9 in any limb. The estimated sample size was 150 subjects. In total, 150 subjects were recruited; the mean age was 62.7 ± 10.2 years, 44.7% were female, and the mean BMI was 24.1 ± 4.1. A total of 63.3% reported hypertension, 42.7% DM, 30.0% hypercholesterolaemia, 38.0% smoking, 18.7% PS, and 6.0% IHD. A total of 30.7% had IMT, 77.3% had CP, and 8.0% had carotid stenosis ≥50%. LI occurred in 64.7%. PAD was diagnosed in 22.0% (95% CI 16.1–29.3). On univariate analysis, based on vascular risk factors alone, PAD was associated with age (p = 0.03), hypercholesterolaemia (p = 0.03), and IHD (p = 0.004). On logistic regression, PAD was only associated with IHD (aOR 6.42, 95% CI 1.25–32.84; p = 0.03). When IMT and CP were added to the model, the association with IHD remained (aOR 5.45, 95% CI 1.03–28.71; p = 0.045). When the results of neuroimaging were added, the association was only with NLI (aOR 2.78, 95% CI 1.09–7.14; p = 0.03). This study found a high prevalence of PAD among Asian patients with IS. It was associated with a non-lacunar infarction. Full article

Background: The Circle of Willis (CoW) is a key collateral pathway that enables communication between the anterior and posterior cerebral circulations. However, anatomical variations in the A1 segment of the anterior cerebral artery, such as hypoplasia or aplasia, can alter hemodynamics and may compromise this collateral function. While incomplete CoW configurations have been linked to aneurysm formation and altered patterns of hemorrhage, their role in the distribution of cerebral infarctions remains controversial. We aimed to explore the association between A1 segment hypoplasia/aplasia and infarct laterality across different etiological subtypes. Methods: We retrospectively analyzed patients with unilateral anterior circulation infarction admitted between April 2017 and March 2023. The CoW was assessed by magnetic resonance angiography (MRA). A1 segment hypoplasia was defined as a segment diameter <1 mm, and A1 aplasia was defined as non-visualization on MRA. The side with hypoplasia or aplasia was defined as the minor side, and the contralateral side as dominant. We assessed whether infarction occurred on the minor or dominant side. Results: Among 198 patients with unilateral anterior circulation infarction classified as lacunar, cardioembolic stroke (CES), or embolic stroke of undetermined source (ESUS), 30% had A1 hypoplasia or aplasia, with similar prevalence across subtypes. Infarcts occurred on the A1 dominant side in 53% of lacunar, 55% of ESUS, and 75% of CES cases. Although this difference did not reach statistical significance (p = 0.43), it should be interpreted with caution given the limited sample size. Conclusions: The rates of A1 hypoplasia and aplasia were similar across stroke types. No statistically significant association was identified. The findings remain inconclusive given the limited sample size. These results should be considered exploratory and hypothesis-generating. Full article

Background: Anatomical variations in the posterior communicating artery (PCoA) are common, but their association with ischemic stroke remains unclear. In this study, we investigated the relationship between PCoA configuration and the localization of perforator infarction. Methods: We conducted a single-center, retrospective observational study of consecutive patients admitted with acute ischemic stroke between April 2016 and July 2023. Patients with a single, unilateral lacunar infarction confined to the thalamic or lenticulostriate artery (LSA) territory were included. PCoA configuration was assessed using time-of-flight magnetic resonance angiography and dichotomized as present (normal PCoA or fetal-type posterior cerebral artery) or absent (hypoplastic or aplastic PCoA). Using a within-patient, hemisphere-based approach, the presence of PCoA on the infarcted side was directly compared with that on the contralateral side. McNemar’s test with continuity correction was used for laterality analysis. Results: A total of 64 patients met the inclusion criteria, including 45 with LSA infarction and 19 with thalamic infarction. The prevalence of PCoA presence on the infarcted hemisphere was 20.0% in the LSA group and 26.3% in the thalamic group, identical to that observed on the contralateral hemisphere in each group. Within-patient comparisons revealed no significant difference in PCoA presence between infarcted and non-infarcted hemispheres in either territory (all p > 0.05). Conclusions: In patients with unilateral perforator infarction involving the thalamic or LSA territories, PCoA configuration was not associated with infarct laterality. These findings suggest that variations in PCoA anatomy have a limited influence on hemispheric vulnerability to perforator infarction, supporting the predominant role of local small-vessel pathology rather than proximal collateral anatomy in the development of lacunar stroke. Full article

Background/Objectives: An embolic stroke of undetermined source (ESUS) is a subtype of ischemic stroke characterized by a non-lacunar infarct in the absence of a clearly identifiable embolic source, despite comprehensive diagnostic evaluation. While ESUS patients are typically younger, have fewer cardiovascular comorbidities, and experience milder strokes than those with cardioembolic strokes (CEs), their functional recovery remains underexplored. Methods: We retrospectively analyzed data from 374 ischemic stroke patients (n = 94 ESUS, n = 280 CE) admitted to the Department of Neurology, University of Pécs, between February 2023 and September 2024. Functional recovery was assessed using the modified Rankin Scale (mRS). Propensity score matching (PSM) was performed to balance the baseline characteristics, and the mRS-shift was compared between groups. Independent predictors of mRS-shift were identified using Huber regression and extreme gradient boosting (XGBoost). Results: The ESUS patients were significantly younger (60.7 ± 13.8 years vs. 75.1 ± 11.3 years, p < 0.001), had lower pre-morbid modified Rankin Scale (pre-mRS) scores (0.34 ± 0.91 vs. 0.81 ± 1.23, p < 0.001), were less likely to have hypertension (75.5% vs. 86.1%, p = 0.027) and diabetes (23.4% vs. 36.8%, p = 0.024), and presented with milder strokes (National Institutes of Health Stroke Scale [NIHSS] score at admission: 5.4 ± 4.5 vs. 8.1 ± 6.3, p < 0.001, and 72 h post-stroke: 3.0 ± 4.4 vs. 6.5 ± 6.3, p < 0.001) compared to the CE patients. After adjusting for baseline differences, the ESUS patients demonstrated significantly greater functional recovery than the CE patients (adjusted mRS-shift: 1.84 ± 1.14 vs. 2.53 ± 1.69, p = 0.022). Age, pre-mRS score, and NIHSS score at 72 h post-stroke were the strongest predictors of mRS-shift, with an older age, a higher pre-mRS score, and a greater stroke severity significantly decreasing the odds of recovery. Conclusions: The ESUS patients showed superior functional recovery compared to the CE patients, even after accounting for baseline differences. These findings highlight the need for further research into the pathomechanisms underlying ESUSs and the development of optimal treatment strategies to improve patient outcomes. Full article

Introduction: The e-STROKE study is a prospective, multicenter observational study designed to assess the impact of various CT parameters (including e-ASPECT, CT perfusion (CTP), collateral flow status, and the size and location of the ischemic lesion) on the clinical outcomes of patients with ischemic stroke, as evaluated by the modified Rankins Scale (mRS) three months post-stroke. This study also aims to investigate whether the use of multimodal CT imaging increases the number of patients eligible for recanalization therapy. The analysis will integrate data from the RES-Q registry and radiological data from the e-STROKE system provided by Brainomix Ltd. Aims: The primary aim is to determine the predictive value of CT parameters (e-ASPECTS, CTP, collateral vessel status, and ischemic lesion volume and location) on three-month functional outcomes, as defined by the mRS, in patients with non-lacunar stroke following recanalization treatment (IVT and/or MT). The secondary aim is to evaluate whether multimodal CT examination leads to an increase in the number of patients eligible for recanalization therapy. Additionally, this study seeks to assess the specificity and sensitivity of multimodal CT in distinguishing stroke mimics from actual strokes. Methods: This multicenter observational study involves patients with suspected acute ischemic stroke and a premorbid mRS ≤ 4, who are treated with endovascular thrombectomy (EVT), intravenous thrombolysis (IVT), or managed conservatively in stroke centers within the Czech Stroke Research Network (STROCZECH), which is part of the Czech Clinical Research Infrastructure Network (CZECRIN). Data collection includes demographic, clinical, and imaging data variables such as age, sex, ethnicity, risk factors, treatment times (OTT, DNT, and OGT), TICI scores, post-treatment hemorrhage (ECAS II), mRS outcome, stroke etiology, e-ASPECTS, acute ischemic volume (AIV), thrombus length on NCCT, CTA collateral score and collateral vessel density, location of large vessel occlusion, ischemic core, hypoperfusion volume, mismatch ratio and volume, final infarct volume, hemorrhage volume, and MRI in case of negative follow-up NCCT. Conclusions: We anticipate collecting robust clinical and radiological data from approximately 2000 patients across 22 centers over a 12-month period. The results are expected to enhance the precision of diagnostic and prognostic radiological markers in managing acute stroke. Full article

Background: Peripheral artery disease (PAD) affects more than 100 million people globally. Most PAD studies have been performed among predominantly White populations—less is known about other ethnicities. The aim of this cross-sectional study was to determine the prevalence and risk factors of PAD in a high-risk Asian population with ischaemic stroke (IS), myocardial infarction, unstable angina (CVD), or diabetes mellitus (DM). Methods: Patients admitted for IS, CVD, or DM were recruited. Data were collected on age, sex, body mass index (BMI), index condition (CVD, IS, DM), history of hypertension, DM, hypercholesterolaemia, cigarette smoking, and claudication. The Edinburgh Claudication Questionnaire was administered, the ankle brachial index (ABI) was determined, and PAD was diagnosed if ABI was ≤0.9. Results: Of the 450 subjects recruited, 150 were placed in each index disease group, the mean age was 61.9 ± 10.32 years, 43.1% were female, and the mean BMI was 23.9 ± 4.3. Hypertension was reported in 59.3%, DM in 63.6%, hypercholesterolaemia in 39.6%, and smoking in 42.9% of patients. The prevalence of PAD was 27.1%, 22.0% in IS, 29.3% in CAD, and 30.0% in DM. PAD was associated with increasing age (adjusted odds ratio (aOR) 1.04/year, 95% confidence interval [CI] 1.01–1.06; p < 0.001), reduced BMI (aOR 0.94, 95% CI 0.89–0.99; p = 0.026), DM (aOR 1.59, 95% CI 1.20–3.18; p = 0.007), and hypercholesterolaemia (aOR 1.82, 95% CI 1.17–2.28; p = 0.007). It was more frequent in non-lacunar versus lacunar acute IS, non-ST segment elevation versus ST-segment elevation acute myocardial infarction, and insulin-treated versus non-insulin-treated DM. Conclusions: Our study showed a high prevalence of PAD among high-risk Asian patients. This was associated with increasing age, DM, and hypercholesterolaemia and inversely associated with BMI. Different rates were found in sub-groups of IS, CVD, and DM. Systematic approaches were used to identify these high-risk individuals and to improve their outcomes. Full article

It is still unclear whether early glycemic profile after admission for acute ischemic stroke (IS) has the same prognostic significance in patients with lacunar and non-lacunar infarction. Data from 4011 IS patients admitted to a Stroke Unit (SU) were retrospectively analyzed. Lacunar IS was diagnosed by clinical criteria. A continuous indicator of early glycemic profile was calculated as the difference of fasting serum glucose (FSG) measured within 48 h after admission and random serum glucose (RSG) measured on admission. Logistic regression was used to estimate the association with a combined poor outcome defined as early neurological deterioration, severe stroke at SU discharge, or 1-month mortality. Among patients without hypoglycemia (RSG and FSG > 3.9 mmol/L), an increasing glycemic profile increased the likelihood of a poor outcome for non-lacunar (OR, 1.38, 95%CI, 1.24–1.52 in those without diabetes; 1.11, 95%CI, 1.05–1.18 in those with diabetes) but not for lacunar IS. Among patients without sustained or delayed hyperglycemia (FSG < 7.8 mmol/L), an increasing glycemic profile was unrelated to outcome for non-lacunar IS but decreased the likelihood of poor outcome for lacunar IS (OR, 0.63, 95%CI, 0.41–0.98). Early glycemic profile after acute IS has a different prognostic significance in non-lacunar and lacunar patients. Full article

Lacunar infarction (LACI), a subtype of acute ischemic stroke, has poor mid- to long-term prognosis due to recurrent vascular events or incident dementia which is difficult to predict using existing clinical data. Herein, we aim to discover blood-based biomarkers for LACI as a complementary prognostic tool. Convalescent plasma was collected from forty-five patients following a non-disabling LACI along with seventeen matched control subjects. The patients were followed up prospectively for up to five years to record an occurrence of adverse outcome and grouped accordingly (i.e., LACI-no adverse outcome, LACI-recurrent vascular event, and LACI-cognitive decline without any recurrence of vascular events). Medium-sized extracellular vesicles (MEVs), isolated from the pooled plasma of four groups, were analyzed by stable isotope labeling and 2D-LC-MS/MS. Out of 573 (FDR < 1%) quantified proteins, 146 showed significant changes in at least one LACI group when compared to matched healthy control. A systems analysis revealed that major elements (~85%) of the MEV proteome are different from the proteome of small-sized extracellular vesicles obtained from the same pooled plasma. The altered MEV proteins in LACI patients are mostly reduced in abundance. The majority of the shortlisted MEV proteins are not linked to commonly studied biological processes such as coagulation, fibrinolysis, or inflammation. Instead, they are linked to oxygen-glucose deprivation, endo-lysosomal trafficking, glucose transport, and iron homeostasis. The dataset is provided as a web-based data resource to facilitate meta-analysis, data integration, and targeted large-scale validation. Full article

Background and Objectives. Ischemic stroke (IS) is one of the leading causes of disability, morbidity, and mortality worldwide. The goal of the study was to evaluate patient demographics, characteristics, and intrahospital mortality among different ischemic stroke subtypes. Materials and Methods. A retrospective observational non-randomized study was conducted, including only ischemic stroke patients, admitted to Pauls Stradins Clinical university hospital, Riga, Latvia, from January of 2016 until December 2020. Ischemic stroke subtypes were determined according to Trial of Org 10172 in Acute Stroke Treatment (TOAST) criteria as a stroke due to (1) large-artery atherosclerosis (atherothrombotic stroke (AS)), (2) cardioembolism (cardioembolic stroke (CS)), (3) small-vessel occlusion (lacunar stroke (LS)), (4) stroke of other determined etiology (other specified stroke (OSS)), and (5) stroke of undetermined etiology (undetermined stroke (US)). The data between different stroke subtypes were compared. Results. There was a slight female predominance among our study population, as 2673 (56.2%) patients were females. In our study group, the most common IS subtypes were cardioembolic stroke (CS), 2252 (47.4%), and atherothrombotic stroke (AS), 1304 (27.4%). CS patients were significantly more severely disabled on admission, 1828 (81.4%), and on discharge, 378 (16.8%), p < 0.05. Moreover, patients with CS demonstrated the highest rate of comorbidities and risk factors. This was also statistically significant, p < 0.05. Differences between the total patient count with no atrial fibrillation (AF), paroxysmal AF, permanent AF, and different IS subtypes among our study population demonstrated not only statistical significance but also a strong association, Cramer’s V = 0.53. The majority of patients in our study group were treated conservatively, 3389 (71.3%). Reperfusion therapy was significantly more often performed among CS patients, 770 (34.2%), p < 0.05. The overall intrahospital mortality among our study population was 570 (12.0%), with the highest intrahospital mortality rate noted among CS patients, 378 (66.3%), p < 0.05. No statistically significant difference was observed between acute myocardial infarction and adiposity, p > 0.05. Conclusions. In our study, CS and AS were the most common IS subtypes. CS patients were significantly older with slight female predominance. CS patients demonstrated the greatest disability, risk factors, comorbidities, reperfusion therapy, and intrahospital mortality. Full article

The blood–brain barrier is the structure (BBB), which isolates the central nervous system from the external environmental. During a stroke, the BBB gets damaged, which is accompanied by changes in the concentrations and distributions of claudin-5, occludin, ZO-1, and other building blocks of the BBB. The aim of this study was to assess the concentrations of selected components of the BBB—occludin, claudin-5, and zonulin (ZO-1)—and to define a potential relationship between the concentrations of these three substances and the type of stroke, the location and extent of the infarct focus, the neurological/functional status in the acute phase of the disease, and the patient’s clinical profile. Methods: In this prospective study, we qualified patients with first-in-life stroke. All patients were analyzed according to: the presence of comorbidities, type of stroke (OCSP), treatment type in the first day of hospitalization, hemorrhagic transformation of infarct focus (ECASS), neurological status on the first day of stroke (NIHSS), functional status (mRS) on the ninth day of disease. In all patients, the plasma concentrations of claudin-5, occludin, and ZO-1 on the first day of stroke were examined and next, the mean concentrations were analyzed and compared between subgroups created on the basis of demographical and clinical features. Results: The mean concentration of occludin was significantly higher in patients with partial anterior cerebral infarct (PACI) compared to patients with posterior cerebral infarct (POCI; 1.03 vs. 0.66 ng/mL; p = 0.009) and in patients with location of ischemic stroke in the carotid artery supply compared with in the vertebrobasilar supply (respectively: 1.036 vs. 0.660 ng/mL; p = 0.009). The mean concentration of claudin 5 was significantly higher in patients with PACI compared to patients with POCI (0.37 vs. 0.21 ng/mL; p = 0.011) and in patients with location of ischemic stroke in the carotid artery supply in comparison with vertebrobasilar supply (respectively: 0.373 vs. 0.249 ng/mL; p = 0.011). The differences in mean occludin and claudin 5 concentrations between female and male were statistically not significant, similarly between patients < 65 years and older. A significantly higher mean concentration of zonulin was observed in patients > 65 years of age compared to younger patients (0.59 vs. 0.48 ng/mL; p = 0.010) and in patients with arterial hypertension compared to patients without the disease (0.63 ng/mL vs. 0.26 ng/mL; p = 0.026). There were no statistically significant relationships between the concentration of occludin, claudin 5, and zonulin and the neurological status according to the NIHSS on the first day of stroke. Conclusions: The location of stroke in the anterior part of the brain’s blood supply is associated with high blood levels of occludin and claudin 5 in the acute phase of stroke. The blood concentration of occludin is significantly lower in lacunar stroke comparing to this in non-lacunar stroke. Old age and arterial hypertension correlate positively with the concentration of zonulin 1 in acute stroke. There is no relationship between the blood levels of occludin, claudin 5, and zonulin 1 on the first day of stroke and the neurological and functional status in the acute phase of the disease. Full article

Background: Cerebral small vessel disease (CSVD) is frequent in patients with cardiovascular risk factors including arterial hypertension, and it is associated with vascular damage in other organs and the risk of stroke, cognitive impairment, and dementia. Early diagnosis of CSVD could prevent deleterious consequences. Objective: To characterize CSVD associated with indicators of subclinical vascular damage in asymptomatic hypertensive patients. Materials and Methods: Participants were hypertensive (HT) and non-hypertensive (non-HT) individuals; without signs of cerebrovascular disease, dementia, and chronic renal failure. For CSVD, white matter hyperintensities (WMH), enlarged Virchow–Robin perivascular spaces (EVRPS), lacunar infarcts, and microbleeds were investigated. Subclinical vascular damage was evaluated (hypertensive retinopathy, microalbuminuria, and extracranial carotid morphology: intima media thickness (IMT) and atheroma plaque). Results: CSVD MRI findings were more frequent in HT; as well as greater intimal thickening. The IMT and/or plaque was significantly associated with all MRI variables; but retinopathy was correlated with EVRPS and lacunar infarcts. Only microalbuminuria was related to the greater severity of WMH in HT. Multivariate analysis evidenced that CSVD was independently associated with the combination of indicators of vascular damage and systolic blood pressure. Conclusions: Combining indicators of subclinical vascular damage, such as carotid morphological variables, microalbuminuria, and hypertensive retinopathy for early detection of CSVD in asymptomatic hypertensive patients could prove to be useful to take actions for the prevention of irreversible brain damage, which could lead to cognitive impairment, dementia and stroke. Full article

Given the high variability of stroke mechanisms, size, localisation and degree of the penumbra, clinicians treating acute stroke patients need tools in addition to clinical information to match the individual patient with different available treatment strategies. Among the two types of perfusion CTs the dynamic perfusion CT is preferable over the whole-brain technique as it can generate truly quantitative regional cerebral blood volume and cerebral blood-flow values and threshold maps that may differentiate reversible from non-reversible ischaemia. Some drawbacks of perfusion CTs, such as the impossibility of serial examinations (amount of contrast, radiation) or failure to show lacunar or posterior fossa lesions, are counterbalanced by the availability of CTs in most emergency rooms, its easy accessibility, simple monitoring of patients and the possibility to quantify perfusion deficits. Perfusion CT has a sensitivity and positive predictive value above 90% for territorial infarcts in the supratentorial regions, even in the earliest phase of stroke. Dynamic perfusion CT reliably identifies penumbra and core tissue and closely predicts final stroke volume. The final stroke size is usually close to the initial core volume if early arterial recanalisation occurs, and close or equal to the initial core plus penumbra size if early recanalisation does not occur (with or without thrombolysis). TIAs or migraine, but not focal seizures or transient global amnesia, may rarely show minor focal hypoperfusion. In regard to information about supratentorial brain perfusion, it appears at least equivalent to MRI perfusion methods. Regarding treatment decisions, the degree of penumbra on perfusion CTs as well as an arterial occlusion on the angio CT could help to select between intraarterial and intravenous thrombolysis. Further studies might show that the current time windows thrombolyses are too long for patients with little penumbra and too short for patients with a persistent penumbra.Therefore, perfusion imaging may allow to replace a rigid time window for acute interventions and the saying “time is brain” might be replaced by “penumbra is brain”. Thus, even patients with unknown onset of stroke, waking up with a stroke or having an epileptic seizure at stroke onset may become candidates for treatment based on the demonstration of a significant penumbra on perfusion imaging. In case neuroprotective treatment becomes available, only patients with a significant penumbra involving the brain matter for which the substance is active (grey versus white brain matter) may be exposed to benefits, costs and side effects of these treatments. When testing new acute stroke therapies, a potential treatment effect may be better shown thanks to selecting patients with perfusion CTs who are more likely to respond to the treatment strategy. In such a study it could be the amount of salvage of the initial radiological penumbra on perfusion CTs that may be used as a surrogate marker to test the efficacy of a new intervention, rather than final infarct size. Full article