Fate of diffusion restricted lesions in acute intracerebral hemorrhage

Systematic Review and Meta-Analysis of the Association Between Appearance of Lesions on Diffusion-Weighted Imaging and Poor Outcomes Among Patients with Intracerebral Hemorrhage

OBJECTIVE

Some patients with intracerebral hemorrhage show lesions on diffusion-weighted magnetic resonance imaging, and such lesions have been associated with a greater risk of worse prognosis. Here we meta-analyzed the available evidence for such an association.

METHODS

Studies that reported the presence or absence of lesions on diffusion-weighted imaging (DWI) after intracerebral hemorrhage as well as clinical or radiological outcomes were systematically reviewed and meta-analyzed. Clinical outcome was defined as a score of modified Rankin scale (mRS) at admission to 90 days.

RESULTS

Ten studies involving 3575 patients were included in the meta-analysis, and the incidence of DWI lesions ranged from 11.1% to 49.6%. Lesions were associated with a significantly higher risk of poor outcome (mRS scores 3-6) across 6 studies (odds ratio: 2.91; 95% confidence interval: 1.62-5.23; P < 0.001). In subgroup analysis, mRS scores 4-6 were associated with the presence of lesions on DWI (odds ratio: 2.18; 95% confidence interval: 1.31-3.60; P = 0.003). We observed similar results using 3 different definitions of lesions on DWI. Some studies have reported that recurrence of intracerebral hemorrhage was also related with DWI lesions. But there was controversy on the relationship between mortality, ischemic stroke, and hematoma volume and DWI lesions.

CONCLUSIONS

Lesions on DWI after intracerebral hemorrhage were associated with a higher risk of poor outcome, but large longitudinal studies are needed to verify this association.

Cognitive Effects of Body Temperature During Hypothermic Circulatory Arrest Trial (GOT ICE): A Randomized Clinical Trial Comparing Outcomes After Aortic Arch Surgery

BACKGROUND

Deep hypothermia has been the standard for hypothermic circulatory arrest (HCA) during aortic arch surgery. However, centers worldwide have shifted toward lesser hypothermia with antegrade cerebral perfusion. This has been supported by retrospective data, but there has yet to be a multicenter, prospective randomized study comparing deep versus moderate hypothermia during HCA.

METHODS

This was a randomized single-blind trial (GOT ICE [Cognitive Effects of Body Temperature During Hypothermic Circulatory Arrest]) of patients undergoing arch surgery with HCA plus antegrade cerebral perfusion at 4 US referral aortic centers (August 2016-December 2021). Patients were randomized to 1 of 3 hypothermia groups: DP, deep (≤20.0 °C); LM, low-moderate (20.1-24.0 °C); and HM, high-moderate (24.1-28.0 °C). The primary outcome was composite global cognitive change score between baseline and 4 weeks postoperatively. Analysis followed the intention-to-treat principle to evaluate if: (1) LM noninferior to DP on global cognitive change score; (2) DP superior to HM. The secondary outcomes were domain-specific cognitive change scores, neuroimaging findings, quality of life, and adverse events.

RESULTS

A total of 308 patients consented; 282 met inclusion and were randomized. A total of 273 completed surgery, and 251 completed the 4-week follow-up (DP, 85 [34%]; LM, 80 [34%]; HM, 86 [34%]). Mean global cognitive change score from baseline to 4 weeks in the LM group was noninferior to the DP group; likewise, no significant difference was observed between DP and HM. Noninferiority of LM versus DP, and lack of difference between DP and HM, remained for domain-specific cognitive change scores, except structured verbal memory, with noninferiority of LM versus DP not established and structured verbal memory better preserved in DP versus HM (P = 0.036). There were no significant differences in structural or functional magnetic resonance imaging brain imaging between groups postoperatively. Regardless of temperature, patients who underwent HCA demonstrated significant reductions in cerebral gray matter volume, cortical thickness, and regional brain functional connectivity. Thirty-day in-hospital mortality, major morbidity, and quality of life were not different between groups.

CONCLUSIONS

This randomized multicenter study evaluating arch surgery HCA temperature strategies found low-moderate hypothermia noninferior to traditional deep hypothermia on global cognitive change 4 weeks after surgery, although in secondary analysis, structured verbal memory was better preserved in the deep group. The verbal memory differences in the low- and high-moderate groups and structural and functional connectivity reductions from baseline merit further investigation and suggest opportunities to further optimize brain perfusion during HCA.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT02834065.

Interaction between cerebral small vessel disease, blood pressure, and remote ischemic lesions in acute spontaneous intracerebral hemorrhage

BACKGROUND

Acute blood pressure (BP) reduction is the first-line treatment for acute spontaneous intracerebral hemorrhage (ICH); however, recent research suggests that intensive BP reduction along with cerebral small vessel disease (cSVD) is a risk factor for remote DWI lesions (RDWILs). We aimed to delineate the interplay between cSVD and BP reduction therapy on the risk of RDWILs.

METHODS

We enrolled 303 patients who underwent brain magnetic resonance imaging within 7 days after acute spontaneous ICH. RDWILs were categorized as occurring in borderzone (BZ) or non-BZ areas. We examined the effect of cSVD, acute BP reduction, and their interaction on RDWILs.

RESULTS

RDWILs were observed in 34 (11%) patients (59.8 ± 10.3-years-old, 24% male). RDWILs were associated with a larger acute weighted average mean arterial pressure (MAP) reduction in the initial 24 h after ICH onset and a higher total cerebral microbleed (CMB) count. Intensive MAP changes (odds ratio (OR) per 10 mmHg 1.76, 95% confidence interval (CI) 1.03-3.20), total CMBs burden (OR per 10 CMBs 1.21, 95% CI 1.08-1.39), and presence of lobar CMBs (OR 7.33, 95% CI 1.59-55.6) were risk factors for RDWILs at BZ, but not at non-BZ. Furthermore, a significant interaction was observed between lobar CMBs and MAP reduction on increased risk of RDWILs at BZ (p = 0.030).

CONCLUSION

cSVD modulates the effect of acute BP reduction on the risk of RDWILs. Patients with extensive microangiopathy have a higher risk of developing cerebral ischemic changes in BZ during unstable hemodynamic status.

Changes in Cerebral Blood Flow and Diffusion-Weighted Imaging Lesions After Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) is a common subtype of stroke and places a great burden on the family and society with a high mortality and disability rate and a poor prognosis. Many findings from imaging and pathologic studies have suggested that cerebral ischemic lesions visualized on diffusion-weighted imaging (DWI) in patients with ICH are not rare and are generally considered to be associated with poor outcome, increased risk of recurrent (ischemic and hemorrhagic) stroke, cognitive impairment, and death. In this review, we describe the changes in cerebral blood flow (CBF) and DWI lesions after ICH and discuss the risk factors and possible mechanisms related to the occurrence of DWI lesions, such as cerebral microangiopathy, cerebral atherosclerosis, aggressive early blood pressure lowering, hyperglycemia, and inflammatory response. We also point out that a better understanding of cerebral DWI lesions will be a key step toward potential therapeutic interventions to improve long-term recovery for patients with ICH.

Remote diffusion-weighted imaging lesions and blood pressure variability in primary intracerebral hemorrhage

Objective

The aim of this study was to examine the association between remote diffusion-weighted imaging lesions (R-DWILs) and blood pressure variability (BPV) in patients with primary intracerebral hemorrhage (ICH).

Methods

We conducted a retrospective review of a consecutive cohort of 375 patients with primary ICH within 24 h onset. R-DWILs were defined as hyperintensity lesions in DWI remote from the hematoma. Blood pressure recordings were extracted up to 24 h post-admission. BPV was measured using SD, coefficient of variation (CV), and successive variation (SV).

Results

Remote DWI lesions were detected in 65 (17.3%) primary ICH patients. In multivariable logistic regression analysis, parameters of BPV were independently associated with R-DWILs, and the results remained consistent after being adjusted with mean SBP. SD, CV, and SV values in the highest quintile, showed 3- to 8-fold increased risk of R-DWILs, compared with the lowest quintile. ΔSBP demonstrated a significant difference in 2 different predictive models. Max SBP only dictated a significant difference in model 1. Mean SBP, admission SBP, and min SBP, failed to present an association with R-DWILs in model 1 or model 2.

Conclusion

Our results provided additional evidence that BPV is associated with the development of R-DWILs in primary ICH.

Effect of Tranexamic Acid Administration on Remote Cerebral Ischemic Lesions in Acute Spontaneous Intracerebral Hemorrhage: A Substudy of a Randomized Clinical Trial

Importance

Hyperintense foci on diffusion-weighted imaging (DWI) that are spatially remote from the acute hematoma occur in 20% of people with acute spontaneous intracerebral hemorrhage (ICH). Tranexamic acid, a hemostatic agent that is under investigation for treating acute ICH, might increase DWI hyperintense lesions (DWIHLs).

Objective

To establish whether tranexamic acid compared with placebo increased the prevalence or number of remote cerebral DWIHLs within 2 weeks of ICH onset.

Design, Setting, and Participants

This prospective nested magnetic resonance imaging (MRI) substudy of a randomized clinical trial (RCT) recruited participants from the multicenter, double-blind, placebo-controlled, phase 3 RCT (Tranexamic Acid for Hyperacute Primary Intracerebral Hemorrhage [TICH-2]) from July 1, 2015, to September 30, 2017, and conducted follow-up to 90 days after participants were randomized to either the tranexamic acid or placebo group. Participants had acute spontaneous ICH and included TICH-2 participants who provided consent to undergo additional MRI scans for the MRI substudy and those who had clinical MRI data that were compatible with the brain MRI protocol of the substudy. Data analyses were performed on an intention-to-treat basis on January 20, 2020.

Interventions

The tranexamic acid group received 1 g in 100-mL intravenous bolus loading dose, followed by 1 g in 250-mL infusion within 8 hours of ICH onset. The placebo group received 0.9% saline within 8 hours of ICH onset. Brain MRI scans, including DWI, were performed within 2 weeks.

Main Outcomes and Measures

Prevalence and number of remote DWIHLs were compared between the treatment groups using binary logistic regression adjusted for baseline covariates.

Results

A total of 219 participants (mean [SD] age, 65.1 [13.8] years; 126 men [57.5%]) who had brain MRI data were included. Of these participants, 96 (43.8%) were randomized to receive tranexamic acid and 123 (56.2%) were randomized to receive placebo. No baseline differences in demographic characteristics and clinical or imaging features were found between the groups. There was no increase for the tranexamic acid group compared with the placebo group in DWIHL prevalence (20 of 96 [20.8%] vs 28 of 123 [22.8%]; odds ratio [OR], 0.71; 95% CI, 0.33-1.53; P = .39) or mean (SD) number of DWIHLs (1.75 [1.45] vs 1.81 [1.71]; mean difference [MD], -0.08; 95% CI, -0.36 to 0.20; P = .59). In an exploratory analysis, participants who were randomized within 3 hours of ICH onset or those with chronic infarcts appeared less likely to have DWIHLs if they received tranexamic acid. Participants with probable cerebral amyloid angiopathy appeared more likely to have DWIHLs if they received tranexamic acid.

Conclusions and Relevance

This substudy of an RCT found no evidence of increased prevalence or number of remote DWIHLs after tranexamic acid treatment in acute ICH. These findings provide reassurance for ongoing and future trials that tranexamic acid for acute ICH is unlikely to induce cerebral ischemic events.

Trial Registration

isrctn.org Identifier: ISRCTN93732214.

Ischemia in intracerebral hemorrhage: A comparative study of small-vessel and large-vessel diseases

Objective

This study aimed to compare effects of cerebral small‐vessel disease (cSVD) burden and cerebral artery stenosis (CAS) on acute ischemia in intracerebral hemorrhage (ICH) and their interaction with mean arterial pressure (MAP) change.

Methods

We recruited consecutive patients with acute primary ICH. Brain magnetic resonance imaging and angiography were performed to quantify diffusion‐weighted imaging (DWI) lesions, CAS, and cSVD markers, which were calculated for the total cSVD score. Multivariable regression models were adopted to explore their associations by DWI lesions size (<15 vs. ≥15 mm) and median MAP change stratification.

Results

Of 305 included patients (mean age 59.5 years, 67.9% males), 77 (25.2%) had DWI lesions (small, 79.2%; large, 20.8%) and 67 (22.0%) had moderate and severe CAS. In multivariable analysis, small DWI lesions were independently associated with higher total cSVD score (odds ratio [OR] 1.81, 95% confidence interval [CI] 1.36–2.41). and large DWI lesions were associated with more severe CAS (OR 2.51, 95% CI 1.17–5.38). This association was modified by MAP change (interaction p = 0.016), with stratified analysis showing an increased risk of large DWI lesions in severe CAS with greater MAP change (≥44 mmHg) (OR 3.48, 95% CI 1.13–10.74) but not with mild MAP change (<44 mmHg) (OR 1.21, 95% CI 0.20–7.34).

Interpretation

Total cSVD burden is associated with small DWI lesions, whereas the degree of CAS is associated with large DWI lesions, specifically with greater MAP change, suggesting that large‐artery atherosclerosis may be involved in ischemic brain injury, which is different from small‐vessel pathogenesis in ICH.

Diffusion-weighted imaging lesions and risk of recurrent stroke after intracerebral haemorrhage

OBJECTIVE

To determine whether the presence of diffusion-weighted imaging-positive (DWI+) lesions is associated with recurrent stroke after intracerebral haemorrhage (ICH).

METHODS

The REstart or STop Antithrombotics Randomised Trial (RESTART) assessed the effect of restarting versus avoiding antiplatelet therapy after ICH on major vascular events for up to 5 years. We rated DWI sequences of MRI done before randomisation for DWI+ lesion presence, masked to outcome and antiplatelet use. Cox proportional hazards regression models were used to quantify associations.

RESULTS

Of 537 participants in RESTART, 247 (median (IQR) age 75.7 (69.6-81.1) years; 170 men (68.8%); 120 started vs 127 avoided antiplatelet therapy) had DWI sequences on brain MRI at a median of 57 days (IQR 19-103) after ICH, of whom 73 (30%) had one or more DWI+ lesion. During a median follow-up of 2 years (1-3), 18 participants had recurrent ICH and 21 had ischaemic stroke. DWI+ lesion presence was associated with all stroke, (adjusted HR 2.2 (95% CI 1.1 to 4.2)) and recurrent ICH (4.8 (95% CI 1.8 to 13.2)), but not ischaemic stroke (0.9 (95% CI 0.3 to 2.5)). DWI+ lesion presence (0.5 (95% CI 0.2 to 1.3)) vs absence (0.6 (95% CI 0.3 to 1.5), p_interaction=0.66) did not modify the effect of antiplatelet therapy on a composite outcome of recurrent stroke.

CONCLUSIONS

DWI+ lesion presence in ICH survivors is associated with recurrent ICH, but not with ischaemic stroke. We found no evidence of modification of effects of antiplatelet therapy on recurrent stroke after ICH by DWI+ lesion presence. These findings provide a new perspective on the significance of DWI+ lesions, which may be markers of microvascular mechanisms associated with recurrent ICH.

TRIAL REGISTRATION NUMBER

ISRCTN71907627.

Intensive Blood Pressure Lowering and DWI Lesions in Intracerebral Hemorrhage: Exploratory Analysis of the ATACH-2 Randomized Trial

BACKGROUND

With the increasing use of magnetic resonance imaging in the assessment of acute intracerebral hemorrhage, diffusion-weighted imaging hyperintense lesions have been recognized to occur at sites remote to the hematoma in up to 40% of patients. We investigated whether blood pressure reduction was associated with diffusion-weighted imaging hyperintense lesions in acute intracerebral hemorrhage and whether such lesions are associated with worse clinical outcomes by analyzing imaging data from a randomized trial.

METHODS

We performed exploratory subgroup analyses in an open-label randomized trial that investigated acute blood pressure lowering in 1000 patients with intracerebral hemorrhage between May 2011 and September 2015. Eligible participants were assigned to an intensive systolic blood pressure target of 110-139 mm Hg versus 140-179 mm Hg with the use of intravenous nicardipine. Of these, 171 patients had requisite magnetic resonance imaging sequences for inclusion in these subgroup analyses. The primary outcome was the presence of diffusion-weighted imaging hyperintense lesions. Secondary outcomes included death or disability and serious adverse event at 90 days.

RESULTS

Diffusion-weighted imaging hyperintense lesions were present in 25% of patients (mean age 62 years). Hematoma volume > 30 cm³ was an adjusted predictor (adjusted relative risk 2.41, 95% confidence interval 1.00-5.80) of lesion presence. Lesions occurred in 25% of intensively treated patients and 24% of standard treatment patients (relative risk 1.01, 95% confidence interval 0.71-1.43, p = 0.97). Patients with diffusion-weighted imaging hyperintense lesions had similar frequencies of death or disability at 90 days, compared with patients without lesions.

CONCLUSIONS

Randomized assignment to intensive acute blood pressure lowering did not result in a greater frequency of diffusion-weighted imaging hyperintense lesion. Alternative mechanisms of diffusion-weighted imaging hyperintense lesion formation other than hemodynamic fluctuations need to be explored. Clinical trial registration ClinicalTrials.gov (Ref. NCT01176565; https://clinicaltrials.gov/ct2/show/NCT01176565 ).

Acute intracerebral haemorrhage and diffusion-weighted imaging lesions: A meta-analysis

INTRODUCTION

Diffusion-weighted imaging lesions in intracerebral haemorrhage are related to a higher risk of recurrent intracerebral haemorrhage, cognitive damage, and mortality. However, it has been reported that the relationship between the risk of diffusion-weighted imaging lesions and intracerebral haemorrhage subtype or the risk factors for diffusion-weighted imaging lesions is variable. This meta-analysis was performed to evaluate this relationship.

METHODS

A systematic literature search up-to August 2020 was performed and 12 studies included 2815 subjects at the baseline with intracerebral haemorrhage. They were reporting relationships between the diffusion-weighted imaging lesions and intracerebral haemorrhage subtype or investigated the risk factors for diffusion-weighted imaging lesions. Odds ratio (OR) with 95% confidence intervals (CIs) was calculated to evaluate the prognostic role of diffusion-weighted imaging lesions and intracerebral haemorrhage subtype and investigated the risk factors for diffusion-weighted imaging lesions using the dichotomous and continuous method with a random or fixed-effect model.

RESULTS

Lobar intracerebral haemorrhage was not significantly related to a higher rate of diffusion-weighted imaging lesions (OR, 1.01; 95% CI, 0.75-1.36, P = .94) compared to the non-lobar intracerebral haemorrhage. Also, history of diabetes mellitus (OR, 1.15; 95% CI, 0.83-1.60, P = .39); history of smoking (OR, 0.95; 95% CI, 0.68-1.33, P = .76); history of hypercholesterolaemia (OR, 1.04; 95% CI, 0.73-1.48, P = .83) and history of ischaemic stroke (OR, 1.63; 95% CI, 0.57-4.66, P = .36) were not significantly related to higher rate of diffusion-weighted imaging lesions compared to no history of those factors. However, the history of hypertension was significantly related to a higher rate of diffusion-weighted imaging lesions (OR, 1.33; 95% CI, 1.04-1.70, P = .02) compared to no history of hypertension. Also, Subjects with diffusion-weighted imaging lesions had a greater decrease in systolic pressure in the acute phase of the intracerebral haemorrhage (OR, 10.23; 95% CI, 7.41-13.06, P < .001) compared to without diffusion-weighted imaging lesions.

CONCLUSIONS

Based on this meta-analysis, the history of hypertension may have an independent risk relationship with a higher rate of diffusion-weighted imaging lesions. Also, subjects with diffusion-weighted imaging lesions had a greater decrease in systolic pressure in the acute phase of the intracerebral haemorrhage compared to those without diffusion-weighted imaging lesions. This relationship forces us to recommend that identification of diffusion-weighted imaging lesions might add appreciated evidence to evaluate the progression of the underlying micro-angiopathy especially in subjects with a history of hypertension. Though further studies are needed to define the mechanisms by which these lesions may lead to cognitive damage and stroke reappearance.

The relation between acute intracerebral hemorrhage and diffusion-weighted imaging lesions: a meta-analysis

Diffusion-weighted imaging lesions in intracerebral hemorrhage are related to a higher risk of recurrent intracerebral hemorrhage, cognitive damage, and mortality. However, it has been reported that the relationship between the risk of diffusion-weighted imaging lesions and intracerebral hemorrhage subtype or the possible risk factors for diffusion-weighted imaging lesions is variable. This meta-analysis was performed to evaluate this relationship. A systematic literature search up-to August 2020 was performed and 12 studies included 2815 subjects at the baseline with intracerebral hemorrhage. Odds ratio (OR) or mean difference (MD) with 95% confidence intervals (CIs) was calculated to evaluate the prognostic role of diffusion-weighted imaging lesions and intracerebral hemorrhage subtype and investigated the possible risk factors for diffusion-weighted imaging lesions using the dichotomous and continuous methods with a random or fixed-effect model. Lobar intracerebral hemorrhage was not significantly related to a higher rate of diffusion-weighted imaging lesions (OR, 1.01; 95% CI, 0.75-1.36, p = 0.94) compared to the non-lobar intracerebral hemorrhage. Also, history of diabetes mellitus (OR, 1.15; 95% CI, 0.83-1.60, p = 0.39); history of smoking (OR, 0.95; 95% CI, 0.68-1.33, p = 0.76); history of hypercholesterolemia (OR, 1.04; 95% CI, 0.73-1.48, p = 0.83); and history of ischemic stroke (OR, 1.63; 95% CI, 0.57-4.66, p = 0.36) were not significantly related to higher rate of diffusion-weighted imaging lesions compared to no history of those factors. However, the history of hypertension was significantly related to a higher rate of diffusion-weighted imaging lesions (OR, 1.33; 95% CI, 1.04-1.70, p = 0.02) compared to no history of hypertension. Also, Subjects with diffusion-weighted imaging lesions had a greater decrease in systolic pressure in the acute phase of the intracerebral hemorrhage (MD, 10.23; 95% CI, 7.41-13.06, p < 0.001) compared to without diffusion-weighted imaging lesions. Based on this meta-analysis, the history of hypertension may have an independent risk relationship with a higher rate of diffusion-weighted imaging lesions. Also, subjects with diffusion-weighted imaging lesions had a greater decrease in systolic pressure in the acute phase of the intracerebral hemorrhage compared to those without diffusion-weighted imaging lesions. This relationship forces us to recommend that identification of diffusion-weighted imaging lesions might add appreciated evidence to evaluate the progression of the underlying micro-angiopathy especially in subjects with a history of hypertension. Though further studies are needed to define the mechanisms by which these lesions may lead to cognitive damage and stroke reappearance.

Predicting new silent cerebral infarction after intracerebral hemorrhage using serum white blood cell count

Background

It has been confirmed that incidental silent cerebral infarctions (SCIs) found in healthy people may be risk factors for cerebrovascular diseases such as strokes and vascular dementia. The prospective study aimed to determine the utility of baseline serum white blood cell (WBC) counts to predict the emergence of new SCI after intracranial hemorrhage (ICH).

Methods

This is a prospective study. From January 2016 to December 2017, we recruited 171 patients admitted to the neurology department of the Affiliated Shuyang Hospital of Xuzhou Medical University with a first episode of ICH. Serum WBC count was measured on admission. SCI was detected by cranial magnetic resonance imaging (MRI) 14 days after the onset of the ICH. Receiver operating characteristic curve analysis was used to calculate the most appropriate cut-off values of the WBC count for differentiating patients with and without SCI at the end of the study period.

Results

New SCIs were detected in 28.07% of patients by cranial MRI. Multivariate logistic regression analysis showed that cerebral microbleeds (CMBs), raised WBC counts, and leukoaraiosis were independent risk factors for SCI. The most appropriate cut-off WBC count differentiating the two groups was 7.65×10⁹/L (sensitivity: 77.08%, specificity: 63.41%).

Conclusion

Elevated levels of serum WBC counts in patients with ICH are associated with SCI. There is potential value in using serum WBC counts to predict new SCI after an acute hemorrhagic stroke.

Stress-Induced Hyperglycemia and Remote Diffusion-Weighted Imaging Lesions in Primary Intracerebral Hemorrhage

BACKGROUND AND PURPOSE

Stress-induced hyperglycemia (SIH) is the relative transient increase in glucose during a critical illness such as intracerebral hemorrhage (ICH) and is likely to play an important role in the pathogenesis of remote diffusion-weighted imaging (DWI) lesion (R-DWIL) in primary ICH. We sought to determine the association between SIH and the occurrence of R-DWILs.

METHODS

We prospectively enrolled primary ICH patients within 14 days after onset from November 2016 to May 2018. In these patients, cerebral magnetic resonance imaging was performed within 14 days after ICH onset. R-DWIL was defined as a hyperintensity signal in DWI with corresponding hypointensity in apparent diffusion coefficient, and at least 20 mm apart from the hematoma. SIH was measured by stress-induced hyperglycemia ratio (SHR). SHR was calculated by fasting blood glucose (FBG) divided by estimated average glucose derived from glycosylated hemoglobin. The included patients were dichotomized into two groups by the 50th percentile of SHR, and named as SHR (-P50) group and SHR (P50+) group, respectively. We evaluated the association between SHR and R-DWIL occurrence using multivariable logistic regression modeling adjusted for potential confounders.

RESULTS

Among the 288 patients enrolled, forty-six (16.0%) of them had one or more R-DWILs. Compared with the patients in the lower 50% of SHR (SHR [-P50]), the odds ratio (OR) [95% confidence interval (CI)] for the higher 50% of SHR (SHR [P50+]) group for R-DWIL occurrence was 3.13 (1.39-7.07) in the total population and 6.33 (2.19-18.30) in population absent of background hyperglycemia after adjusting for potential covariates. Similar results were observed after further adjusted for FBG.

CONCLUSIONS

Our study demonstrated that SIH was associated with the occurrence of R-DWILs in patients with primary ICH within 14 days of symptom onset.

Cerebral Microembolism in Intracerebral Hemorrhage: A Prospective Case-Control Study

BACKGROUND

Small and remote acute ischemic lesions may occur in up to one-third of patients with spontaneous intracerebral hemorrhage (ICH). Possible mechanisms include cerebral embolism, small vessel disease, blood pressure variability and others. The embolic mechanism has not been adequately studied. Using transcranial Doppler (TCD), we assessed the incidence of spontaneous microembolic signals (MESs) in patients with acute ICH.

METHODS

Twenty acute ICH patients were prospectively evaluated within 48 h of hospital admission. Clinical and imaging data were collected. Continuous TCD monitoring was performed in both middle cerebral arteries for a one-hour period on days 1, 3 and 7 of hospital admission. Monitoring was performed in the emergency room, ICU or ward, according to patient location. We compared the frequency and risk factors for MES in patients with ICH and in 20 age- and gender-matched controls without history of ischemic or hemorrhagic stroke.

RESULTS

The mean age was 57.5 ± 14.1 years, and 60% were male. MESs were detected in 7 patients with ICH and in one control patient without ICH (35% vs 5%, p = 0.048). The frequency of MES on day 1 was 15% (3 of 20 patients), on day 3, 26% (5 of 19 patients) and on day 7, 37.5% (3 of 8 patients). Among patients with ICH, those with MES had a tendency to higher frequencies of dyslipidemia (83% vs 33%, p = 0.13) and lobar location of hemorrhages (71% vs 30%, p = 0.15). Two out of 6 patients with ICH who also underwent MRI had remote DWI lesions, of whom one showed MES on TCD.

CONCLUSION

Micro-embolic signals occur in over one-third of patients with ICH. Further research is needed to identify the sources of cerebral microembolism and their relationship with small acute infarcts in ICH.

Association between the hydrogenase level and the occurrence of remote diffusion-weighted imaging lesions after spontaneous intracerebral hemorrhage

To explore the influence of serum lactate dehydrogenase (LDH) level on remote diffusion-weighted imaging lesions (rDWILs) after spontaneous intracerebral hemorrhage (ICH). A consecutive cohort of 160 patients with spontaneous ICH who had brain MRI within 4 weeks of ICH onset were collected and analyzed retrospectively. rDWILs showed high signal on diffusion-weighted image (DWI) while low signal on apparent diffusion coefficient (ADC), and at least 20 mm away from the hemorrhage focus. The blood samples were obtained within 24 h after ICH onset from all patients. Lactate dehydrogenase (LDH) levels in blood were collected from serum biochemical tests. We use multivariate logistic regression analyses to investigate the association between serum LDH level and rDWILs after ICH. The average serum LDH level was 186.5 ± 35.6 U/L. And this level was higher in patients who presented rDWILs than in those without rDWILs. With the best cut-off value of 191 by using receiver operating characteristic (ROC) analysis, elevated LDH was associated with the presence of rDWILs independently (OR = 1.024, 95%CI = 1.011-1.037, P < 0.001) in the bivariate logistic regression analysis with adjustment for age, sex, previous ischemic stroke/TIA, smoker, SBP on admission, hematoma volume, and intraventricular hemorrhage (IVH). The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) of LDH ≥ 191 U/L for rDWILs were 70.4%, 72.2%, 33.9%, 94.2%, respectively. Our study suggests serum LDH level has a significant correlation with rDWILs after spontaneous ICH. Patients with higher serum LDH level in 24 h after ICH onset may be a useful predictor for rDWILs occurrence.

Early elevated neutrophil-to-lymphocyte ratio associated with remote diffusion-weighted imaging lesions in acute intracerebral hemorrhage

AIMS

To explore the relationship between the circulating neutrophil-to-lymphocyte ratio (NLR) and the remote diffusion-weighted imaging lesions (R-DWILs) after spontaneous intracerebral hemorrhage (ICH).

METHODS

Consecutive patients with spontaneous ICH were prospectively collected from November 2016 to May 2018 and retrospectively analyzed. We included subjects who presented within 24 hours after symptom onset and were free of detectable infections on admission or in hospital. Blood samples were obtained at 24-48 hours after ICH ictus, while all complete MRI scans were performed at 5-8 days. R-DWILs were defined as focal hyperintensities remote from the site of the ICH or the peri-hematoma regions. NLR was calculated by dividing the absolute neutrophil counts by the absolute lymphocyte counts. Multivariate binary logistic regression models were generated to evaluate the relationship between NLR and R-DWILs.

RESULTS

One hundred sixty-three subjects met eligibility criteria (age 62.3 ± 13.6 years, 60.7% males), of whom 31(19.0%) experienced R-DWILs. Higher circulating NLR was documented in patients with R-DWILs. With the best cutoff value of 6.01, elevated NLR was independently associated with the presence of R-DWILs (OR = 3.170, 95% CI 1.306-7.697, P = .011) in the bivariate logistic regression analysis with adjustment for age, sex, atrial fibrillation, previous ischemic stroke/TIA, SBP on admission, hematoma volume, and IVH.

CONCLUSIONS

This study provides significant evidence of the association between circulating NLR and R-DWILs in spontaneous ICH patients. Patients with NLR > 6.01 at 24-48 hours after ICH ictus should be paid more attention to when evaluating R-DWILs.

Prevalence and clinical relevance of diffusion-weighted imaging lesions

Objective

To examine the association of diffusion-weighted image (DWI) lesions with markers of cerebrovascular disease, neurodegeneration, and cognitive functioning and to further explore the evolution of these DWI lesions and their link to risk of dementia, stroke, or TIA in the Rotterdam Study.

Methods

Two thousand one hundred seventy-six participants with baseline MRI scans (assessed between January 2009 and December 2013) and data on incident clinical outcomes (until January 2016) were included. DWIs were inspected for presence of acute or subacute lesions. Markers of cerebrovascular disease, brain tissue segmentation, and microstructural integrity were collected. Cognition was assessed with a detailed neuropsychological test. Evolution of DWI lesions was evaluated on follow-up scans.

Results

Thirty-three individuals (1.5%) had ≥1 DWI lesions. Persons with lacunes, white matter hyperintensities (WMHs), and reduced white matter microstructural integrity were more likely to have DWI lesions. Persons with DWI lesions performed worse on Stroop test 1. For 17 of 33 persons, follow-up scans were available to determine lesion evolution. During a mean follow-up of 4.7 years, 58.8% of DWI lesions appeared as WMHs, 17.6% developed cavitation, 5.9% changed into cortical cerebral microinfarcts, and 17.6% disappeared. People with DWI lesions at baseline were at increased risk of strokes (hazard ratio 3.72, 95% confidence interval 1.35–10.27).

Conclusion

Asymptomatic DWI lesions in community-dwelling persons are associated with markers of cerebral small vessel disease, reduced microstructural integrity, and worse cognition. Presence of DWI lesions increases the risk of further strokes. Future investigations will have to show whether screening and treating persons with DWI lesions can effectively reduce the burden of stroke.

Clinical relevance of acute cerebral microinfarcts in vascular cognitive impairment

Objective

To determine the occurrence of acute cerebral microinfarcts (ACMIs) in memory clinic patients and relate their presence to vascular risk and cognitive profile, CSF and neuroimaging markers, and clinical outcome.

Methods

The TRACE-VCI study is a memory clinic cohort of patients with vascular brain injury on MRI (i.e., possible vascular cognitive impairment [VCI]). We included 783 patients (mean age 67.6 ± 8.5, 46% female) with available 3T diffusion-weighted imaging (DWI). ACMIs were defined as supratentorial DWI hyperintensities <5 mm with a corresponding hypo/isointense apparent diffusion coefficient signal and iso/hyperintense T2*-weighted signal.

Results

A total of 23 ACMIs were found in 16 of the 783 patients (2.0%). Patients with ACMIs did not differ in vascular risk or cognitive profile, but were more often diagnosed with vascular dementia (odds ratio [OR] 5.1; 95% confidence interval [CI] 1.4–18.9, p = 0.014). ACMI presence was associated with lower levels of β-amyloid (p < 0.004) and with vascular imaging markers (lacunar infarcts: OR 3.5, CI 1.3–9.6, p = 0.015; nonlacunar infarcts: OR 4.1, CI 1.4–12.5, p = 0.012; severe white matter hyperintensities: OR 4.8, CI 1.7–13.8, p = 0.004; microbleeds: OR 18.9, CI 2.5–144.0, p = 0.0001). After a median follow-up of 2.1 years, the risk of poor clinical outcome (composite of marked cognitive decline, major vascular event, death, and institutionalization) was increased among patients with ACMIs (hazard ratio 3.0; 1.4–6.0, p = 0.005).

Conclusion

In patients with possible VCI, ACMI presence was associated with a high burden of cerebrovascular disease of both small and large vessel etiology and poor clinical outcome. ACMIs may thus be a novel marker of active vascular brain injury in these patients.

Association between remote diffusion-weighted imaging lesions and cerebral small vessel disease in primary intracerebral hemorrhage

BACKGROUND AND PURPOSE

The aim of this study was to examine the association amongst remote diffusion-weighted imaging lesions (R-DWILs), imaging markers of cerebral small vessel disease (cSVD) and total cSVD burden in patients with primary intracerebral haemorrhage (ICH).

METHODS

In total, 344 consecutive primary ICH patients were enrolled prospectively. R-DWILs on magnetic resonance imaging as well as four imaging markers of cSVD, including cerebral microbleeds (CMBs), white matter hyperintensities (WMHs), lacunes and enlarged perivascular spaces, were rated with validated scales. The total cSVD score was calculated by adding up these four markers. Univariate and multivariate analyses were performed.

RESULTS

Remote DWI lesions were detected in 57 (16.6%) primary ICH patients. On multivariate logistic regression analysis, the presence of CMBs [odds ratio (OR) 5.26, 95% confidence interval (CI) 1.72-16.12], of high-grade WMHs (OR 4.68, 95% CI 2.01-10.90), the presence of lacunes (OR 2.69, 95% CI 1.20-6.06), mixed CMBs (OR 2.93, 95% CI 1.35-6.36), mixed lacunes (OR 3.60, 95% CI 1.25-10.37), periventricular WMHs (OR 2.19, 95% CI 1.40-3.44), deep WMHs (OR 1.92, 95% CI 1.24-2.97) and total WMHs (OR 1.52, 95% CI 1.20-1.94) were associated with the presence of R-DWILs. A significant association was also found between high-grade total cSVD score and R-DWILs (OR 1.97, 95% CI 1.36-2.84). This association remained significant in patients stratified by an age of 60 years or more than 60 years.

CONCLUSIONS

Remote DWI lesions are correlated with the severity of each imaging marker of cSVD and with the total burden of cSVD.

New Silent Cerebral Infarction in Patients with Acute Non-Cerebral Amyloid Angiopathy Intracerebral Hemorrhage as a Predictor of Recurrent Cerebrovascular Events

BACKGROUND The aim of this study was to investigate the incidence and related risk factors of new silent cerebral infarction in patients with acute non-cerebral amyloid angiopathy (non-CAA) intracerebral hemorrhage (ICH) and to explore clinical cerebrovascular event recurrence within 1 year. MATERIAL AND METHODS This prospective study observed 152 patients with non-CAA ICH diagnosed by computed tomography within 3 days after onset. All patients underwent magnetic resonance imaging on day 14 to identify silent cerebral infarction, and their subsequent clinical cerebrovascular events were followed up regularly within 1 year. RESULTS Of the 152 patients, 46 (30.26%) had silent cerebral infarctions. Multiple logistic regression analysis revealed that the white blood cell (WBC) count, cerebral microbleeds (CMBs), and leukoaraiosis were silent cerebral infarction risk factors. At 1-year follow-up, 34 (22.37%) had clinical cerebrovascular events, with 8 (23.53%) having vascular-related deaths. Multiple logistic regression analysis showed that silent cerebral infarction was the only independent predictor of future clinical cerebrovascular events. CONCLUSIONS Silent cerebral infarction is common during acute non-CAA ICH and is independently related to WBC counts, CMBs, and leukoaraiosis. The risk of clinical cerebrovascular events in non-CAA ICH patients with silent cerebral infarction increases in the following year; thus, silent cerebral infarction may be a useful predictor of recurrent cerebrovascular events.

Diffusion-Weighted Imaging Hyperintensities in Subtypes of Acute Intracerebral Hemorrhage: Meta-Analysis

Background and Purpose- Diffusion-weighted imaging (DWI) hyperintensities in intracerebral hemorrhage (ICH) are associated with increased risk of recurrent ICH, cognitive impairment, and death, but whether these lesions are specific to a subtype of ICH remains uncertain. We investigated the association between DWI lesions and ICH subtype and explored the risk factors for DWI lesions. Methods- In a systematic review of ICH studies, we identified those reporting prevalence of DWI lesions. Two reviewers independently assessed study eligibility and risk of bias and collected data. We determined the pooled prevalence of DWI lesions within 90 days after ICH onset for cerebral amyloid angiopathy- and hypertensive angiopathy-related ICH using random-effects meta-analysis. We calculated odds ratios to compare prevalence of DWI lesions by ICH subtype and to assess risk factors for DWI lesions. Results- Eleven studies (1910 patients) were included. The pooled prevalence of DWI lesions was 18.9% (95% CI, 11.1-26.7) in cerebral amyloid angiopathy- and 21.0% (95% CI, 15.3-26.6) in hypertensive angiopathy-related ICH. There was no difference in the prevalence of DWI lesions between cerebral amyloid angiopathy- (64/292 [21.9%]) and hypertensive angiopathy-related ICH (79/370 [21.4%]; odds ratio, 1.25; 95% CI, 0.73-2.15) in the 5 studies reporting data on both ICH pathogeneses. In all ICH, presence of DWI lesions was associated with neuroimaging features of microangiopathy (leukoaraiosis extension, previous ICH, and presence, and number of microbleeds) but not with vascular risk factors or the use of antithrombotic therapies. Conclusions- Prevalence of DWI lesions in acute ICH averages 20%, with no difference between cerebral amyloid angiopathy- and hypertensive angiopathy-related ICH. Detection of DWI lesions may add valuable information to assess the progression of the underlying microangiopathy.

Acute ischaemic lesions are associated with cortical superficial siderosis in spontaneous intracerebral hemorrhage

BACKGROUND AND PURPOSE

Diffusion-weighted imaging (DWI) commonly detects acute ischaemic lesions in patients with acute intracerebral hemorrhage (ICH), especially with cerebral amyloid angiopathy (CAA). We investigated the relationship between cortical superficial siderosis (cSS), a neuroimaging marker of CAA, and DWI lesions in patients with acute ICH.

METHODS

We conducted a retrospective analysis of prospectively collected data from consecutive patients with acute supratentorial ICH who underwent brain magnetic resonance imaging within 10 days after symptom onset. Magnetic resonance imaging scans were analyzed for DWI lesions, cSS and other markers for small-vessel disease. Univariate and multivariate analyses were performed to assess the association between cSS and DWI lesions.

RESULTS

Among 246 ICH survivors (mean age 71.4 ± 12.6 years) who were enrolled, 126 had lobar ICH and 120 had deep ICH. Overall, DWI lesions were observed in 38 (15.4%) patients and were more common in patients with lobar ICH than deep ICH (22.2% vs. 8.3%; P = 0.003). In multivariate logistic regression analysis, the extent of white matter hyperintensities [odds ratio (OR), 1.29; 95% confidence interval (CI), 1.05-1.58; P = 0.02] and cSS severity (focal cSS: OR, 3.54; 95% CI, 1.28-9.84; disseminated cSS: OR, 4.41; 95% CI, 1.78-10.97; P = 0.001) were independently associated with the presence of DWI lesions.

CONCLUSIONS

Diffusion-weighted imaging lesions are more frequently observed in patients with acute lobar ICH than in those with deep ICH. cSS severity and white matter hyperintensity extent are independent predictors for the presence of DWI lesions, suggesting that CAA may be involved in the pathogenesis of DWI lesions associated with acute ICH.

Cerebral ischemia and deterioration with lower blood pressure target in intracerebral hemorrhage

Objective

To determine the incidence and predictors of acute cerebral ischemia and neurologic deterioration in intracerebral hemorrhage (ICH) patients after an institutional protocol change in systolic blood pressure (SBP) target from <160 to <140 mm Hg.

Methods

We retrospectively compared persons admitted with primary ICH before and after a protocol change in SBP target from <160 to <140 mm Hg. The primary outcomes were presence of acute cerebral ischemia on MRI completed within 2 weeks of ICH and acute neurologic deterioration.

Results

Of 286 persons with primary ICH, 119 underwent MRI and met inclusion criteria. Sixty-two had a target SBP <160 mm Hg (group 1) and 57 had a target SBP <140 mm Hg (group 2). There were no differences between the 2 groups in baseline clinical and radiographic characteristics, but over the first 24 hours of hospitalization, group 2 had lower mean SBP (134 vs 143 mm Hg, p < 0.001) and lower minimum SBP over 72 hours (106 vs 112 mm Hg, p = 0.02). Acute cerebral ischemia was more frequent in group 2 than in group 1 (32% vs 16%; p = 0.047) as was acute neurologic deterioration (19% vs 5%; p = 0.022). A minimum SBP ≤120 mm Hg over 72 hours was associated with cerebral ischemia, while no patient with a minimum SBP ≥130 mm Hg had cerebral ischemia. Acute cerebral ischemia was significantly associated with worse discharge NIH Stroke Scale score, while SBP target was not.

Conclusions

Intensive lowering of SBP <140 mm Hg in acute ICH, particularly allowing SBP <120 mm Hg, is associated with increased remote cerebral ischemic lesions and acute neurologic deterioration.

Association of Renal Dysfunction With Remote Diffusion-Weighted Imaging Lesions and Total Burden of Cerebral Small Vessel Disease in Patients With Primary Intracerebral Hemorrhage

Objective: Remote diffusion-weighted imaging (DWI) lesions (R-DWIL) found in intracerebral hemorrhage (ICH) patients are considered as an additional marker of cerebral small vessel disease (cSVD). This study aimed to investigate the association of renal dysfunction and R-DWIL, as well as the total burden of cSVD on magnetic resonance imaging among patients with primary ICH. Methods: One hundred and twenty-six consecutive patients were prospectively enrolled. R-DWIL on DWI, as well as other imaging markers of cSVD, including lacunes, white matter lesions, cerebral microbleeds, and enlarged perivascular spaces were rated using validated scales. Renal dysfunction was evaluated either by reduced estimated glomerular filtration rate (eGFR) or the presence of proteinuria or increased cystatin C. Results: After adjustments for potential confounders by logistic regression, impaired eGFR [odds ratio (OR) 6.00, 95% confidence interval (CI) 1.73-20.78], proteinuria (OR 3.07, 95% CI 1.25-7.54) and increased cystatin C (OR 2.73, 95% CI 1.11-6.72) were correlated with presence of R-DWIL. A similar association was also found between cystatin C levels (OR 3.16, 95% CI 1.39-7.19), proteinuria (OR 2.79, 95% CI 1.34-5.83) and the comprehensive cSVD burden. Conclusions: Renal dysfunction are associated with the presence of R-DWIL, and total burden of cSVD in patients with primary ICH.

Factors Associated With Remote Diffusion-Weighted Imaging Lesions in Spontaneous Intracerebral Hemorrhage

Background and purpose

Remote diffusion-weighted imaging lesions (R-DWILs) have been detected in patients with spontaneous intracerebral hemorrhage (ICH) and may be correlated with clinical outcome. However, the mechanisms and characteristics of R-DWILs have not been fully elucidated. In this study, we sought to demonstrate the clinical characteristics of R-DWILs in spontaneous ICH.

Methods

We prospectively collected data with spontaneous ICH patients from November 2016 to December 2017. In these patients, cerebral magnetic resonance imaging was performed within 28 days after ICH onset. R-DWIL was defined as a hyperintensity signal in diffusion-weighted imaging with corresponding hypointensity in apparent diffusion coefficient, and at least 20 mm apart from the hematoma. We compared two groups of patients with or without R-DWIL with the demographic and clinical characteristics, laboratory parameters, and imaging characteristics, by using univariate and multivariate analysis.

Results

Of the 222 patients enrolled, a total of 75 R-DWILs were observed in 41 patients (18.5%). Among these lesions, the cortical and subcortical areas were the predominant locations with a proportion of 77.3%. The median diameter of R-DWILs was 7 mm (range 2–20 mm). Twelve patients were found having more than one lesion, with five among which showed R-DWILs in multiple cerebral arterial territories. In multivariate modeling, higher fasting glucose (OR 1.231; 95% CI 1.035–1.465; p = 0.019) and more severe white matter hyperintensity (WMH) (OR 6.589; 95% CI 2.975–14.592; p < 0.001) were independent factors related to the presence of R-DWILs.

Conclusion

In our study, approximately one-fifth of ICH patients showed coexistence of R-DWIL. Higher fasting glucose and more severe WMH were associated with R-DWIL occurrence in spontaneous ICH.

Remote Diffusion-Weighted Imaging Lesions in Intracerebral Hemorrhage: Characteristics, Mechanisms, Outcomes, and Therapeutic Implications

Spontaneous intracerebral hemorrhage (ICH) is one of the most fatal form of stroke, with high mortality and disability rate. Small diffusion-weighed imaging lesions are not rare to see in regions remote from the hematoma after ICH and have been generally considered as related with poor outcome. In this review, we described the characteristics of remote ischemic lesions, discussed the possible mechanisms and clinical outcomes of these lesions, and evaluated the potential therapeutic implications.

Evolution of DWI lesions in cerebral amyloid angiopathy: Evidence for ischemia

OBJECTIVE

To address the pathophysiologic nature of small diffusion-weighted imaging (DWI) lesions in patients with cerebral amyloid angiopathy (CAA) who underwent serial MRI. Specifically, we tested (1) whether DWI lesions occurred preferentially in individuals with prior DWI lesions, (2) the cross-sectional association with chronic cortical cerebral microinfarcts (CMIs), and (3) the evolution of DWI lesions over time.

METHODS

Patients with probable CAA (n = 79) who underwent at least 2 MRI sessions were included. DWI lesions were assessed at each available time point. Lesion appearance and characteristics were assessed on available structural follow-up images. Presence and burden of other neuroimaging markers of small vessel disease (white matter hyperintensities, cerebral microbleeds, cortical superficial siderosis, and chronic cortical CMIs) were assessed as well.

RESULTS

Among 221 DWI scans (79 patients with 2 DWI scans; 40 with ≥3), 60 DWI lesions were found in 28 patients. Patients with DWI lesions at baseline were not more likely to have additional DWI lesions on follow-up compared to patients without DWI lesions at baseline. DWI lesions were associated with chronic cortical CMIs and cortical superficial siderosis, but not with other markers. For 39/60 DWI lesions, >1 MRI sequence was available at follow-up to determine lesion evolution. Twenty-four (62%) were demarcated as chronic lesions on follow-up MRI. Five appeared as cavitations, 18 as noncavitated infarcts, and 1 underwent hemorrhagic transformation.

CONCLUSIONS

Based on their neuroimaging signature as well as their association with chronic cortical CMIs, DWI lesions appear to have an ischemic origin and represent one part of the CMI spectrum.

Ischemic lesions, blood pressure dysregulation, and poor outcomes in intracerebral hemorrhage

OBJECTIVE

To evaluate the associations among diffusion-weighted imaging (DWI) lesions, blood pressure (BP) dysregulation, MRI markers of small vessel disease, and poor outcome in a large, prospective study of primary intracerebral hemorrhage (ICH).

METHODS

The Ethnic/Racial Variations of Intracerebral Hemorrhage (ERICH) study is a multicenter, observational study of ICH among white, black, and Hispanic patients.

RESULTS

Of 600 patients, mean (±SD) age was 60.8 ± 13.6 years, median (interquartile range) ICH volume was 9.1 mL (3.5-20.8), and 79.6% had hypertension. Overall, 26.5% of cases had DWI lesions, and this frequency differed by race/ethnicity (black 33.8%, Hispanic 24.9%, white 20.2%, overall p = 0.006). A logistic regression model of variables associated with DWI lesions included lower age (odds ratio [OR] 0.721, p = 0.002), higher first recorded systolic BP (10-unit OR 1.12, p = 0.002), greater change in mean arterial pressure (MAP) prior to the MRI (10-unit OR 1.10, p = 0.037), microbleeds (OR 1.99, p = 0.008), and higher white matter hyperintensity (WMH) score (1-unit OR 1.16, p = 0.002) after controlling for race/ethnicity, leukocyte count, and acute in-hospital antihypertensive treatment. A second model of variables associated with poor 90-day functional outcome (modified Rankin Scale scores 4-6) included DWI lesion count (OR 1.085, p = 0.034) as well as age, ICH volume, intraventricular hemorrhage, Glasgow Coma Scale score, WMH score, race/ethnicity, acute in-hospital antihypertensive treatment, and ICH location.

CONCLUSIONS

These results support the hypotheses that acute BP dysregulation is associated with the development of DWI lesions in primary ICH and that DWI lesions are, in turn, associated with poor outcomes.

Design and Experimental Evaluation of a Non-Invasive Microwave Head Imaging System for Intracranial Haemorrhage Detection

An intracranial haemorrhage is a life threatening medical emergency, yet only a fraction of the patients receive treatment in time, primarily due to the transport delay in accessing diagnostic equipment in hospitals such as Magnetic Resonance Imaging or Computed Tomography. A mono-static microwave head imaging system that can be carried in an ambulance for the detection and localization of intracranial haemorrhage is presented. The system employs a single ultra-wideband antenna as sensing element to transmit signals in low microwave frequencies towards the head and capture backscattered signals. The compact and low-profile antenna provides stable directional radiation patterns over the operating bandwidth in both near and far-fields. Numerical analysis of the head imaging system with a realistic head model in various situations is performed to realize the scattering mechanism of haemorrhage. A modified delay-and-summation back-projection algorithm, which includes effects of surface waves and a distance-dependent effective permittivity model, is proposed for signal and image post-processing. The efficacy of the automated head imaging system is evaluated using a 3D-printed human head phantom with frequency dispersive dielectric properties including emulated haemorrhages with different sizes located at different depths. Scattered signals are acquired with a compact transceiver in a mono-static circular scanning profile. The reconstructed images demonstrate that the system is capable of detecting haemorrhages as small as 1 cm³. While quantitative analyses reveal that the quality of images gradually degrades with the increase of the haemorrhage’s depth due to the reduction of signal penetration inside the head; rigorous statistical analysis suggests that substantial improvement in image quality can be obtained by increasing the data samples collected around the head. The proposed head imaging prototype along with the processing algorithm demonstrates its feasibility for potential use in ambulances as an effective and low cost diagnostic tool to assure timely triaging of intracranial hemorrhage patients.

Enlarged perivascular spaces and small diffusion-weighted lesions in intracerebral hemorrhage

OBJECTIVE

To examine the association between enlarged perivascular spaces (EPVS) and the prevalence and extent of small acute diffusion-weighted imaging (DWI) lesions (SA-DWIL) in patients with spontaneous supratentorial intracerebral hemorrhage (ICH).

METHODS

We conducted a retrospective review of a consecutive cohort of 201 patients with spontaneous supratentorial ICH who had brain MRI with DWI within 1 month of ICH onset. We compared the clinical and imaging characteristics, including EPVS, of patients with and without SA-DWIL. We used univariate and multivariate logistic regression analyses to determine the variables associated with SA-DWIL.

RESULTS

Small acute DWI lesions were detected in 27.9% (n = 56) of patients. Intraventricular and subarachnoid extension of ICH (p ≤ 0.001), high centrum semiovale (CSO)-EPVS (p < 0.001), high basal ganglia-EPVS (p = 0.007), overall extent of white matter hyperintensity (p = 0.018), initial ICH volume (p < 0.001), and mean change in mean arterial blood pressure (δ MAP = MAP at admission - the lowest MAP before MRI scan) (p = 0.027) were associated with SA-DWIL on univariate analyses. On multivariate logistic regression analyses, larger ICH volume (odds ratio [OR] 1.03; 95% confidence interval [CI] 1.01-1.06; p = 0.006) and high CSO-EPVS (OR 12.56; 95% CI 4.40-35.85; p < 0.001) were independently associated with the presence of SA-DWIL.

CONCLUSIONS

In our cohort, high EPVS, in particular CSO-EPVS, and larger hematoma volume emerged as independent predictors for SA-DWIL after ICH. Our findings might provide a new explanation for the pathophysiologic mechanisms predisposing to SA-DWIL after ICH.

Silent New Brain Lesions: Innocent Bystander or Guilty Party?

With the advances in magnetic resonance imaging, previously unrecognized small brain lesions, which are mostly asymptomatic, have been increasingly detected. Diffusion-weighted imaging can identify small ischemic strokes, while gradient echo T2* imaging and susceptibility-weighted imaging can reveal tiny hemorrhagic strokes (microbleeds). In this article, we review silent brain lesions appearing soon after acute stroke events, including silent new ischemic lesions and microbleeds appearing 1) after acute ischemic stroke and 2) after acute intracerebral hemorrhage. Moreover, we briefly discuss the clinical implications of these silent new brain lesions.