Independent Validation of the Hematoma Expansion Prediction Score: A Non-contrast Score Equivalent in Accuracy to the Spot Sign.

BACKGROUND AND PURPOSE: The computed tomography angiography (CTA) spot sign is widely used to assess the risk of hematoma expansion following acute intracerebral hemorrhage (ICH). However, not all patients can receive intravenous contrast nor are all hospital systems equipped with this technology. We aimed to independently validate the Hematoma Expansion Prediction (HEP) Score, an 18-point non-contrast prediction scale, in an external cohort and compare its diagnostic capability to the CTA spot sign. METHODS: We performed a retrospective analysis of the predicting hematoma growth and outcome in intracerebral hemorrhage using contrast bolus CT (PREDICT) Cohort Study. Primary outcome was significant hematoma expansion (≥ 6 mL or ≥ 33%). We generated a receiver operating characteristic (ROC) curve comparing the HEP score to significant expansion. We calculated sensitivity, specificity, positive and negative predictive values (PPV/NPV) for each score point. We determined independent predictors of significant hematoma expansion via logistic regression. RESULTS: A total of 292 patients were included in primary analysis. Hematoma growth of ≥ 6 mL or ≥ 33% occurred in 94 patients (32%). The HEP score was associated with significant expansion (adjusted odds ratio [aOR] 1.14, 95% confidence interval [CI] 1.01-1.30). ROC curves comparing HEP score to significant expansion had an area under the curve of 0.64 (95% CI 0.57-0.71). Youden's method showed an optimum score of 4. HEP Scores ≥ 4 (n = 100, sensitivity 49%, specificity 73%, PPV 46%, NPV 75%, aOR 1.99, 95% CI 1.09-3.64) accurately predicted significant expansion. PPV increased with higher HEP scores, but at the cost of lower sensitivity. The diagnostic characteristics of the spot sign (n = 82, Sensitivity 49%, Specificity 81%, PPV 55%, NPV 76%, aOR 2.95, 95% CI 1.61-5.42) were similar to HEP scores ≥ 4. CONCLUSION: The HEP score is predictive of significant expansion (≥ 6 mL or ≥ 33%) and is comparable to the spot sign in diagnostic accuracy. Non-contrast prediction tools may have a potential role in the recruitment of patients in future intracerebral hemorrhage trials.

Do Intracerebral Hemorrhage Nonexpanders Actually Expand Into the Ventricular Space?

BACKGROUND AND PURPOSE: The computed tomographic angiography spot sign as a predictor of hematoma expansion is limited by its modest sensitivity and positive predictive value. It is possible that hematoma expansion in spot-positive patients is missed because of decompression of intracerebral hemorrhage (ICH) into the ventricular space. We hypothesized that revising hematoma expansion definitions to include intraventricular hemorrhage (IVH) expansion will improve the predictive performance of the spot sign. Our objectives were to determine the proportion of ICH nonexpanders who actually have IVH expansion, determine the proportion of false-positive spot signs that have IVH expansion, and compare the known predictive performance of the spot sign to a revised definition incorporating IVH expansion. METHODS: We analyzed patients from the multicenter PREDICT ICH spot sign study. We defined hematoma expansion as ≥6 mL or ≥33% ICH expansion or >2 mL IVH expansion and compared spot sign performance using this revised definition with the conventional 6 mL/33% definition using receiver operating curve analysis. RESULTS: Of 311 patients, 213 did not meet the 6-mL/33% expansion definition (nonexpanders). Only 13 of 213 (6.1%) nonexpanders had ≥2 mL IVH expansion. Of the false-positive spot signs, 4 of 40 (10%) had >2 mL ventricular expansion. The area under the curve for spot sign to predict significant ICH expansion was 0.65 (95% confidence interval, 0.58-0.72), which was no different than when IVH expansion was added to the definition (area under the curve, 0.66; 95% confidence interval, 0.58-0.71). CONCLUSIONS: Although IVH expansion does indeed occur in a minority of ICH nonexpanders, its inclusion into a revised hematoma expansion definition does not alter the predictive performance of the spot sign.

Lack of Early Improvement Predicts Poor Outcome Following Acute Intracerebral Hemorrhage.

OBJECTIVES: There are limited data as to what degree of early neurologic change best relates to outcome in acute intracerebral hemorrhage. We aimed to derive and validate a threshold for early postintracerebral hemorrhage change that best predicts 90-day outcomes. DESIGN: Derivation: retrospective analysis of collated clinical stroke trial data (Virtual International Stroke Trials Archive). VALIDATION: retrospective analysis of a prospective multicenter cohort study (Prediction of haematoma growth and outcome in patients with intracerebral haemorrhage using the CT-angiography spot sign [PREDICT]). SETTING: Neurocritical and ICUs. PATIENTS: Patients with acute intracerebral hemorrhage presenting less than 6 hours. Derivation: 552 patients; validation: 275 patients. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We generated a receiver operating characteristic curve for the association between 24-hour National Institutes of Health Stroke Scale change and clinical outcome. The primary outcome was a modified Rankin Scale score of 4-6 at 90 days; secondary outcomes were other modified Rankin Scale score ranges (modified Rankin Scale, 2-6, 3-6, 5-6, 6). We employed Youden's J Index to select optimal cut points and calculated sensitivity, specificity, and predictive values. We determined independent predictors via multivariable logistic regression. The derived definitions were validated in the PREDICT cohort. Twenty-four-hour National Institutes of Health Stroke Scale change was strongly associated with 90-day outcome with an area under the receiver operating characteristic curve of 0.75. Youden's method showed an optimum cut point at -0.5, corresponding to National Institutes of Health Stroke Scale change of greater than or equal to 0 (a lack of clinical improvement), which was seen in 46%. Early neurologic change accurately predicted poor outcome when defined as greater than or equal to 0 (sensitivity, 65%; specificity, 73%; positive predictive value, 70%; adjusted odds ratio, 5.05 [CI, 3.25-7.85]) or greater than or equal to 4 (sensitivity, 19%; specificity, 98%; positive predictive value, 91%; adjusted odds ratio, 12.24 [CI, 4.08-36.66]). All definitions reproduced well in the validation cohort. CONCLUSIONS: Lack of clinical improvement at 24 hours robustly predicted poor outcome and showed good discrimination for individual patients who would do poorly. These findings are useful for prognostication and may also present as a potential early surrogate outcome for future intracerebral hemorrhage treatment trials.

Analysis of Workflow and Time to Treatment on Thrombectomy Outcome in the Endovascular Treatment for Small Core and Proximal Occlusion Ischemic Stroke (ESCAPE) Randomized, Controlled Trial.

BACKGROUND: The Endovascular Treatment for Small Core and Proximal Occlusion Ischemic Stroke (ESCAPE) trial used innovative imaging and aggressive target time metrics to demonstrate the benefit of endovascular treatment in patients with acute ischemic stroke. We analyze the impact of time on clinical outcome and the effect of patient, hospital, and health system characteristics on workflow within the trial. METHODS AND RESULTS: Relationship between outcome (modified Rankin Scale) and interval times was modeled by using logistic regression. Association between time intervals (stroke onset to arrival in endovascular-capable hospital, to qualifying computed tomography, to groin puncture, and to reperfusion) and patient, hospital, and health system characteristics were modeled by using negative binomial regression. Every 30-minute increase in computed tomography-to-reperfusion time reduced the probability of achieving a functionally independent outcome (90-day modified Rankin Scale 0-2) by 8.3% (P=0.006). Symptom onset-to-imaging time was not associated with outcome (P>0.05). Onset-to-endovascular hospital arrival time was 42% (34 minutes) longer among patients receiving intravenous alteplase at the referring hospital (drip and ship) versus direct transfer (mothership). Computed tomography-to-groin puncture time was 15% (8 minutes) shorter among patients presenting during work hours versus off hours, 41% (24 minutes) shorter in drip-ship patients versus mothership, and 43% (22 minutes) longer when general anesthesia was administered. The use of a balloon guide catheter during endovascular procedures shortened puncture-to-reperfusion time by 21% (8 minutes). CONCLUSIONS: Imaging-to-reperfusion time is a significant predictor of outcome in the ESCAPE trial. Inefficiencies in triaging, off-hour presentation, intravenous alteplase administration, use of general anesthesia, and endovascular techniques offer major opportunities for improvement in workflow. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01778335.

Extracranial Venous abnormalities: A true pathological finding in patients with multiple sclerosis or an anatomical variant?

OBJECTIVE: To evaluate the extracranial venous anatomy with contrast-enhanced MR venogram (CE-MRV) in patients without multiple sclerosis (MS), and assess the prevalence of various venous anomalies such as asymmetry and stenosis in this population. MATERIALS AND METHODS: We prospectively recruited 100 patients without MS, aged 18-60 years, referred for contrast-enhanced MRI. They underwent additional CE-MRV from skull base to mediastinum on a 3T scanner. Exclusion criteria included prior neck radiation, neck surgery, neck/mediastinal masses or significant cardiac or pulmonary disease. Two neuroradiologists independently evaluated the studies to document asymmetry and stenosis in the jugular veins and prominence of collateral veins. RESULTS: Asymmetry of internal jugular veins (IJVs) was found in 75 % of subjects. Both observers found stenosis in the IJVs with fair agreement. Most stenoses were located in the upper IJV segments. Asymmetrical vertebral veins and prominence of extracranial collateral veins, in particular the external jugular veins, was not uncommon. CONCLUSION: It is common to have stenoses and asymmetry of the IJVs as well as prominence of the collateral veins of the neck in patients without MS. These findings are in contrast to prior reports suggesting collateral venous drainage is rare except in MS patients. KEY POINTS: • The venous anatomy of the neck in patients without MS demonstrates multiple variants • Asymmetry and stenoses of the internal jugular veins are common • Collateral neck veins are not uncommon in patients without MS • These findings do not support the theory of chronic cerebrospinal venous insufficiency • MR venography is a useful imaging modality for assessing venous anatomy.

Hypoattenuation on CTA images with large vessel occlusion: timing affects conspicuity.

PURPOSE: Parenchymal hypoattenuation distal to occlusions on CTA source images (CTASI) is perceived because of the differences in tissue contrast compared to normally perfused tissue. This difference in conspicuity can be measured objectively. We evaluated the effect of contrast timing on the conspicuity of ischemic areas. METHODS: We collected consecutive patients, retrospectively, between 2012 and 2014 with large vessel occlusions that had dynamic multiphase CT angiography (CTA) and CT perfusion (CTP). We identified areas of low cerebral blood volume on CTP maps and drew the region of interest (ROI) on the corresponding CTASI. A second ROI was placed in an area of normally perfused tissue. We evaluated conspicuity by comparing the absolute and relative change in attenuation between ischemic and normally perfused tissue over seven time points. RESULTS: The median absolute and relative conspicuity was greatest at the peak arterial (8.6 HU (IQR 5.1-13.9); 1.15 (1.09-1.26)), notch (9.4 HU (5.8-14.9); 1.17 (1.10-1.27)), and peak venous phases (7.0 HU (3.1-12.7); 1.13 (1.05-1.23)) compared to other portions of the time-attenuation curve (TAC). There was a significant effect of phase on the TAC for the conspicuity of ischemic vs normally perfused areas (P < 0.00001). CONCLUSION: The conspicuity of ischemic areas distal to a large artery occlusion in acute stroke is dependent on the phase of contrast arrival with dynamic CTASI and is objectively greatest in the mid-phase of the TAC.

Perihematomal Edema Is Greater in the Presence of a Spot Sign but Does Not Predict Intracerebral Hematoma Expansion.

BACKGROUND AND PURPOSE: Perihematomal edema volume may be related to intracerebral hemorrhage (ICH) volume at baseline and, consequently, with hematoma expansion. However, the relationship between perihematomal edema and hematoma expansion has not been well established. We aimed to investigate the relationship among baseline perihematomal edema, the computed tomographic angiography spot sign, hematoma expansion, and clinical outcome in patients with acute ICH. METHODS: Predicting Hematoma Growth and Outcome in Intracerebral Hemorrhage Using Contrast Bolus CT (PREDICT) was a prospective observational cohort study of ICH patients presenting within 6 hours from onset. Patients underwent computed tomography and computed tomographic angiography scans at baseline and 24-hour computed tomography scan. A post hoc analysis of absolute perihematomal edema and relative perihematomal edema (absolute perihematomal edema divided by ICH) volumes was performed on baseline computed tomography scans (n=353). Primary outcome was significant hematoma expansion (>6 mL or >33%). Secondary outcomes were early neurological deterioration, 90-day mortality, and poor outcome. RESULTS: Absolute perihematomal edema volume was higher in spot sign patients (24.5 [11.5-41.8] versus 12.6 [6.9-22] mL; P<0.001), but it was strongly correlated with ICH volume (ρ=0.905; P<0.001). Patients who experienced significant hematoma expansion had higher absolute perihematomal edema volume (18.4 [10-34.6] versus 11.8 [6.5-22] mL; P<0.001) but similar relative perihematomal edema volume (1.09 [0.89-1.37] versus 1.12 [0.88-1.54]; P=0.400). Absolute perihematomal edema volume and poorer outcomes were higher by tertiles of ICH volume, and perihematomal edema volume did not independently predict significant hematoma expansion. CONCLUSIONS: Perihematomal edema volume is greater at baseline in the presence of a spot sign. However, it is strongly correlated with ICH volume and does not independently predict hematoma expansion.

Intra-Arterial Therapy and Post-Treatment Infarct Volumes: Insights From the ESCAPE Randomized Controlled Trial.

BACKGROUND AND PURPOSE: The goal of reperfusion therapy in acute ischemic stroke is to limit brain infarction. The objective of this study was to investigate whether the beneficial effect of endovascular treatment on functional outcome could be explained by a reduction in post-treatment infarct volume. METHODS: The Endovascular Treatment for Small Core and Anterior Circulation Proximal Occlusion With Emphasis on Minimizing CT to Recanalization Times (ESCAPE) trial was a multicenter randomized open-label trial with blinded outcome evaluation. Among 315 enrolled subjects (endovascular treatment n=165; control n=150), 314 subject's infarct volumes at 24 to 48 hours on magnetic resonance imaging (n=254) or computed tomography (n=60) were measured. Post-treatment infarct volumes were compared by treatment assignment and recanalization/reperfusion status. Appropriate statistical models were used to assess relationship between baseline clinical and imaging variables, post-treatment infarct volume, and functional status at 90 days (modified Rankin Scale). RESULTS: Median post-treatment infarct volume in all subjects was 21 mL (interquartile range =65 mL), in the intervention arm, 15.5 mL (interquartile range =41.5 mL), and in the control arm, 33.5 mL (interquartile range =84 mL; P<0.01). Baseline National Institute of Health Stroke Scale (P<0.01), site of occlusion (P<0.01), baseline noncontrast computed tomographic scan Alberta Stroke Program Early CT score (ASPECTS) (P<0.01), and recanalization (P<0.01) were independently associated with post-treatment infarct volume, whereas age, sex, treatment type, intravenous alteplase, and time from onset to randomization were not (P>0.05). Post-treatment infarct volume (P<0.01) and delta National Institute of Health Stroke Scale (P<0.01) were independently associated with 90-day modified Rankin Scale, whereas laterality (left versus right) was not. CONCLUSIONS: These results support the primary results of the ESCAPE trial and show that the biological underpinning of the success of endovascular therapy is a reduction in infarct volume. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01778335.

Infarct in a New Territory After Treatment Administration in the ESCAPE Randomized Controlled Trial (Endovascular Treatment for Small Core and Anterior Circulation Proximal Occlusion With Emphasis on Minimizing CT to Recanalization Times).

BACKGROUND AND PURPOSE: Infarct in a new previously unaffected territory (INT) is a potential complication of endovascular treatment. We applied a recently proposed methodology to identify and classify INTs in the ESCAPE randomized controlled trial (Endovascular Treatment for Small Core and Anterior Circulation Proximal Occlusion With Emphasis on Minimizing CT to Recanalization Times). METHODS: The core laboratory identified INTs on 24-hour follow-up imaging, blinded to treatment allocation, after assessing all baseline imaging. INTs were classified into 3 types (I-III) and 2 subtypes (A/B) based on size and if catheter manipulation was likely performed across the vessel territory ostium. Logistic regression was used to understand the effect of multiple a priori identified variables on INT occurrence. Ordinal logistic regression was used to analyze the effect of INTs on modified Rankin Scale shift at 90 days. RESULTS: From 308 patients included, 14 INTs (4.5% overall; 2.8% on follow-up noncontrast computed tomography, 11.7% on follow-up magnetic resonance imaging) were identified (5.0% in endovascular treatment arm versus 4.0% in control arm [P=0.7]). The use of intravenous alteplase was associated with a 68% reduction in the odds of INT occurrence (3.0% with versus 9.1% without; odds ratio, 0.32; 95% confidence interval, 0.11-0.96; adjusted for age, sex, and treatment type). No other variables were associated with INTs. INT occurrence was associated with reduced probability of good clinical outcome (common odds ratio, 0.25; 95% confidence interval, 0.09-0.74; adjusted for age, type of treatment, and follow-up scan). CONCLUSIONS: INTs are uncommon, detected more frequently on follow-up magnetic resonance imaging, and affect clinical outcome. In experienced centers, endovascular treatment is likely not causal, whereas intravenous alteplase may be therapeutic. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01778335.

Quantitative non-contrast measurements improve diagnosing dural venous sinus thrombosis.

INTRODUCTION: The only direct sign of sinus thrombosis on non-contrast computerized tomography (NCCT) is the hyperdense sign. The purpose of our study was to assess quantitative parameters for diagnosis of superficial venous sinus thrombosis and to compare these quantitative criteria with the current standard of qualitative evaluation. METHODS: This retrospective case-control study included 18 patients with acute superficial sinus thrombosis and 18 matched controls. Three blinded readers independently evaluated the NCCT for the presence of hyperdense sign using axial slices only followed by axial slices with multiplanar reformats. Absolute attenuation values and ratios were calculated for thrombosed and non-thrombosed sinuses: Ratiotarget sinus/lowest attenuation sinus, Ratiotarget sinus/basilar artery, Ratiotarget sinus/internal carotid artery, Ratiotarget sinus/temporal lobe, and Ratiotarget sinus/frontal lobe. RESULTS: There was a significant difference in absolute attenuation values and ratios between thrombosed and non-thrombosed sinuses, with the absolute attenuation and the Ratiotarget sinus/lowest attenuation sinus being the most differentiating. The mean attenuation for thrombosed sinuses was 69 Hounsfield units (HU) (95 % CI 65-72 HU) vs. 52 HU (95 % CI 51-54) for non-thrombosed, P < 0.0001. The mean Ratiotarget/lowest attenuation was 1.5 (95 % CI 1.4-1.6) for thrombosed sinuses vs. 1.1 (95 % CI 1.0-1.1) for non-thrombosed, P < 0.0001. Optimal thresholds of 62 HU and 1.3 yielded sensitivities of 81 and 84 %, respectively. Hyperdense sign had a sensitivity of 63 % on axial images and 67 % with the addition of multiplanar reformats. CONCLUSION: Density measurements result in substantial improvement over visual inspection in the diagnosis of superficial venous sinus thrombosis on NCCT.

Serial Quantitative Computed Tomography Perfusion in Aneurysmal Subarachnoid Hemorrhage.

PURPOSE: Computed tomography perfusion (CTP) has been performed to predict which patients with aneurysmal subarachnoid hemorrhage are at risk of developing delayed cerebral ischemia (DCI). Patients with severe arterial narrowing may have significant reduction in perfusion. However, many patients have less severe arterial narrowing. There is a paucity of literature evaluating perfusion changes which occur with mild to moderate narrowing. The purpose of our study was to investigate serial whole-brain CTP/computed tomography angiography in aneurysm-related subarachnoid hemorrhage (aSAH) patients with mild to moderate angiographic narrowing. METHODS: We retrospectively studied 18 aSAH patients who had baseline and follow-up whole-brain CTP/computed tomography angiography. Thirty-one regions of interest/hemisphere at six levels were grouped by vascular territory. Arterial diameters were measured at the circle of Willis. The correlation between arterial diameter and change in CTP values, change in CTP in with and without DCI, and response to intra-arterial vasodilator therapy in DCI patients was evaluated. RESULTS: There was correlation among the overall average cerebral blood flow (CBF; R=0.49, p<0.04), mean transit time (R=-0.48, p=0.04), and angiographic narrowing. In individual arterial territories, there was correlation between changes in CBF and arterial diameter in the middle cerebral artery (R=0.53, p=0.03), posterior cerebral artery (R=0.5, p=0.03), and anterior cerebral artery (R=0.54, p=0.02) territories. Prolonged mean transit time was correlated with arterial diameter narrowing in the middle cerebral artery territory (R=0.52, p=0.03). Patients with DCI tended to have serial worsening of CBF compared with those without DCI (p=0.055). CONCLUSIONS: Our preliminary study demonstrates there is a correlation between mild to moderate angiographic narrowing and serial changes in perfusion in patients with aSAH. Patients developing DCI tended to have progressively worsening CBF compared with those not developing DCI.

Mechanical Thrombectomy in Acute Ischemic Stroke: A Systematic Review.

Although intravenous thrombolysis increases the probability of a good functional outcome in carefully selected patients with acute ischemic stroke, a substantial proportion of patients who receive thrombolysis do not have a good outcome. Several recent trials of mechanical thrombectomy appear to indicate that this treatment may be superior to thrombolysis. We therefore conducted a systematic review and meta-analysis to evaluate the clinical effectiveness and safety of new-generation mechanical thrombectomy devices with intravenous thrombolysis (if eligible) compared with intravenous thrombolysis (if eligible) in patients with acute ischemic stroke caused by a proximal intracranial occlusion. We systematically searched seven databases for randomized controlled trials published between January 2005 and March 2015 comparing stent retrievers or thromboaspiration devices with best medical therapy (with or without intravenous thrombolysis) in adults with acute ischemic stroke. We assessed risk of bias and overall quality of the included trials. We combined the data using a fixed or random effects meta-analysis, where appropriate. We identified 1579 studies; of these, we evaluated 122 full-text papers and included five randomized control trials (n=1287). Compared with patients treated medically, patients who received mechanical thrombectomy were more likely to be functionally independent as measured by a modified Rankin score of 0-2 (odds ratio, 2.39; 95% confidence interval, 1.88-3.04; I2=0%). This finding was robust to subgroup analysis. Mortality and symptomatic intracerebral hemorrhage were not significantly different between the two groups. Mechanical thrombectomy significantly improves functional independence in appropriately selected patients with acute ischemic stroke.

Validation of the 9-Point and 24-Point Hematoma Expansion Prediction Scores and Derivation of the PREDICT A/B Scores.

BACKGROUND AND PURPOSE: Nine- and 24-point prediction scores have recently been published to predict hematoma expansion (HE) in acute intracerebral hemorrhage. We sought to validate these scores and perform an independent analysis of HE predictors. METHODS: We retrospectively studied 301 primary or anticoagulation-associated intracerebral hemorrhage patients presenting <6 hours post ictus prospectively enrolled in the Predicting Hematoma Growth and Outcome in Intracerebral Hemorrhage Using Contrast Bolus Computed Tomography (PREDICT) study. Patients underwent baseline computed tomography angiography and 24-hour noncontrast computed tomography follow-up for HE analysis. Discrimination and calibration of the 9- and 24-point scores was assessed. Independent predictors of HE were identified using multivariable regression and incorporated into the PREDICT A/B scores, which were then compared with existing scores. RESULTS: The 9- and 24-point HE scores demonstrated acceptable discrimination for HE>6 mL or 33% and >6 mL, respectively (area under the curve of 0.706 and 0.755, respectively). The 24-point score demonstrated appropriate calibration in the PREDICT cohort (χ2 statistic, 11.5; P=0.175), whereas the 9-point score demonstrated poor calibration (χ2 statistic, 34.3; P<0.001). Independent HE predictors included spot sign number, time from onset, warfarin use or international normalized ratio>1.5, Glasgow Coma Scale, and National Institutes of Health Stroke Scale and were included in PREDICT A/B scores. PREDICT A showed improved discrimination compared with both existing scores, whereas performance of PREDICT B varied by definition of expansion. CONCLUSIONS: The 9- and 24-point expansion scores demonstrate acceptable discrimination in an independent multicenter cohort; however, calibration was suboptimal for the 9-point score. The PREDICT A score showed improved discrimination for HE prediction but requires independent validation.

Intracerebral Hematoma Morphologic Appearance on Noncontrast Computed Tomography Predicts Significant Hematoma Expansion.

BACKGROUND AND PURPOSE: Hematoma expansion in intracerebral hemorrhage is associated with higher morbidity and mortality. The computed tomography (CT) angiographic spot sign is highly predictive of expansion, but other morphological features of intracerebral hemorrhage such as fluid levels, density heterogeneity, and margin irregularity may also predict expansion, particularly in centres where CT angiography is not readily available. METHODS: Baseline noncontrast CT scans from patients enrolled in the Predicting Hematoma Growth and Outcome in Intracerebral Hemorrhage Using Contrast Bolus CT (PREDICT) study were assessed for the presence of fluid levels and degree of density heterogeneity and margin irregularity using previously validated scales. Presence and grade of these metrics were correlated with the presence of hematoma expansion as defined by the PREDICT study on 24-hour follow-up scan. RESULTS: Three hundred eleven patients were included in the analysis. The presence of fluid levels and increasing heterogeneity and irregularity were associated with 24-hour hematoma expansion (P=0.021, 0.003 and 0.049, respectively) as well as increases in absolute hematoma size. Fluid levels had the highest positive predictive value (50%; 28%-71%), whereas margin irregularity had the highest negative predictive value (78%; 71%-85). Noncontrast metrics had comparable predictive values as spot sign for expansion when controlled for vitamin K, antiplatelet use, and baseline National Institutes of Health Stroke Scale, although in a combined area under the receiver-operating characteristic curve model, spot sign remained the most predictive. CONCLUSIONS: Fluid levels, density heterogeneity, and margin irregularity on noncontrast CT are associated with hematoma expansion at 24 hours. These markers may assist in prediction of outcomes in scenarios where CT angiography is not readily available and may be of future help in refining the predictive value of the CT angiography spot sign.

Survival analysis of risk factors for major recurrence of intracranial aneurysms after coiling.

BACKGROUND: Recurrence after intracranial aneurysm coiling is a highly prevalent outcome, yet to be understood. We investigated clinical, radiological and procedural factors associated with major recurrence of coiled intracranial aneurysms. METHODS: We retrospectively analyzed prospectively collected coiling data (2003-12). We recorded characteristics of aneurysms, patients and interventional techniques, pre-discharge and angiographic follow-up occlusion. The Raymond-Roy classification was used; major recurrence was a change from class I or II to class III, increase in class III remnant, and any recurrence requiring any type of retreatment. Identification of risk factors associated with major recurrence used univariate Cox Proportional Hazards Model followed by multivariate regression analysis of covariates with P<0.1. RESULTS: A total of 467 aneurysms were treated in 435 patients: 283(65%) harboring acutely ruptured aneurysms, 44(10.1%) patients died before discharge and 33(7.6%) were lost to follow-up. A total of 1367 angiographic follow-up studies (range: 1-108 months, Median [interquartile ranges (IQR)]: 37[14-62]) was performed in 384(82.2%) aneurysms. The major recurrence rate was 98(21%) after 6(3.5-22.5) months. Multivariate analysis (358 patients with 384 aneurysms) revealed the risk factors for major recurrence: age>65 y (hazard ratio (HR): 1.61; P=0.04), male sex (HR: 2.13; P<0.01), hypercholesterolemia (HR: 1.65; P=0.03), neck size ≥4 mm (HR: 1.79; P=0.01), dome size ≥7 mm (HR: 2.44; P<0.01), non-stent-assisted coiling (HR: 2.87; P=0.01), and baseline class III (HR: 2.18; P<0.01). CONCLUSION: Approximately one fifth of the intracranial aneurysms resulted in major recurrence. Modifiable factors for major recurrence were choice of stent-assisted technique and confirmation of adequate baseline occlusion (Class I/II) in the first coiling procedure.

Factors Determining Periprocedural and Long-term Complications of High Risk Carotid Artery Stenting.

BACKGROUND AND PURPOSE: Carotid artery stenting (CAS) has been, historically, an alternative to open endarterectomy (CEA) for stroke prevention in high risk patients with carotid atherosclerosis. We sought to determine the rates of periprocedural and long-term stroke or death and the risk factors for complications after CAS in our high risk patient population. METHODS: Clinical and treatment variables of consecutive CAS procedures performed between 2002 and 2011 were analyzed. Using univariate and multivariate logistic regression analyses we examined how patient characteristics influenced outcomes and changes in modified Rankin Score (mRS). RESULTS: In 152 patients, the composite total of periprocedural death, stroke, transient ischemic attack (TIA) and myocardial infarction (MI) rate was 3.95% (6/152). Chronic kidney disease (CKD) was strongly associated with periprocedural complications (p<0.001). Coronary artery disease/peripheral vascular disease (CAD/PVD) (p=0.03), dyslipidemia (p=0.02), CKD (p=0.01), and contralateral internal carotid artery stenosis (p=0.02) were non-modifiable risk factors for mRS increase. There were 25 deaths, 8 strokes, 11 TIAs, and 1 MI (mean follow-up 38.4 months, range 0-116 months). The presence of CAD/PVD (p=0.009) and dyslipidemia (p=0.002) were significantly associated with long-term complications. CONCLUSION: CAS was performed with low periprocedural complications in high-risk patients. Our rates compare very favorably to large-scale trials that have ideal patients. This data encourages the consideration of CAS in patients considered high risk for CEA and provides possible patient characteristics (CKD) to help with periprocedural risk stratification.

Computed tomographic angiography and cerebral blood volume can predict final infarct volume and outcome after recanalization.

BACKGROUND AND PURPOSE: Recanalization rates are higher in acute anterior stroke treated with stent-retrievers when compared with older techniques. However, some still have sizeable infarcts and poor outcome. This may be related to underestimation of core infarct on nonenhanced computed tomography (NECT). CT angiography (CTA) source images (CTASI) and CT perfusion may be more informative. We hypothesize that core infarct estimation with NECT, CTA, and CT perfusion predicts infarct at 24 hours and outcome after fast recanalization. METHODS: Consecutive good recanalization patients with proximal anterior circulation stroke were evaluated. We assessed Alberta Stroke Program Early CT Score (ASPECTs) on NECT for subtle early infarct, hypodensity, loss of gray-white (CTASI), and low cerebral blood volume (CBV; CT perfusion). Sensitivity and specificity for predicting infarct by region were calculated. RESULTS: Of 46 patients, 36 (78%) had successful thrombectomy. Median ASPECTS was 10 for NECT early infarct and frank hypodensity; for CBV, CTASI-ASPECTS was 8. CTASI had the highest sensitivity of 71% and specificity of 82% for 24 hours NECT infarct. There was moderate correlation and concordance between CBV/24-hour NECT (Rp=0.51; Rc=0.50) and CTASI/24-hour NECT (Rp=0.54 and Rc=0.53). Thirty-four patients (74%) had good outcomes. Median ASPECTS was higher on CTASI (8 versus 5; P=0.04) and CBV (9 versus 5; P=0.03) for patients with good versus bad outcome. There were better outcomes with increasing CTASI-ASPECTS (P=0.004) and CBV-ASPECTS (P=0.02). CONCLUSIONS: CTASI and CBV were better at predicting 24-hour infarct and outcome than NECT. Appropriate advanced imaged guided selection may improve outcomes in large-vessel stroke treated with the newest techniques.

Venous phase of computed tomography angiography increases spot sign detection, but intracerebral hemorrhage expansion is greater in spot signs detected in arterial phase.

BACKGROUND AND PURPOSE: Variability in computed tomography angiography (CTA) acquisitions may be one explanation for the modest accuracy of the spot sign for predicting intracerebral hemorrhage expansion detected in the multicenter Predicting Hematoma Growth and Outcome in Intracerebral Hemorrhage Using Contrast Bolus CT (PREDICT) study. This study aimed to determine the frequency of the spot sign in intracerebral hemorrhage and its relationship with hematoma expansion depending on the phase of image acquisition. METHODS: PREDICT study was a prospective observational cohort study of patients with intracerebral hemorrhage presenting within 6 hours from onset. A post hoc analysis of the Hounsfield units of an artery and venous structure were measured on CTA source images of the entire PREDICT cohort in a core laboratory. Each CTA study was classified into arterial or venous phase and into 1 of 5 specific image acquisition phases. Significant hematoma expansion and total hematoma enlargement were recorded at 24 hours. RESULTS: Overall (n=371), 77.9% of CTA were acquired in arterial phase. The spot sign, present in 29.9% of patients, was more frequently seen in venous phase as compared with arterial phase (39% versus 27.3%; P=0.041) and the later the phase of image acquisition (P=0.095). Significant hematoma expansion (P=0.253) and higher total hematoma enlargement (P=0.019) were observed more frequently among spot sign-positive patients with earlier phases of image acquisition. CONCLUSIONS: Later image acquisition of CTA improves the frequency of spot sign detection. However, spot signs identified in earlier phases may be associated with greater absolute enlargement. A multiphase CTA including arterial and venous acquisitions could be optimal in patients with intracerebral hemorrhage.

Navigation of Stents across Communicating Arteries for Aneurysm Embolization.

INTRODUCTION: Endovascular coiling of aneurysms crossing the Circle of Willis has been described in small case series. The technical challenges in manipulating a stent across the Circle of Willis lie in negotiating difficult angles and small arteries. We present our experience with treating aneurysms by stent assistance in which the Circle of Willis was crossed to facilitate optimal stent deployment. MATERIALS AND METHODS: We retrospectively reviewed the cases in our institution from January 2009 to June 2012 in which the Circle of Willis was traversed to facilitate optimal stent deployment. We measured the diameter of the communicating arteries traversed, caliber of the target arteries in which the stent was deployed and the most acute angle negotiated ("critical angle"). We compare our results with other published series in the literature. RESULTS: Eight patients fulfilled the criteria: 5 males (45-66 years). There were three anterior and five posterior circulation aneurysms. Four of the aneurysms were ruptured. The PCOM was traversed in five cases, the ACOM in three cases. The mean diameter of the communicating artery was 1.17 mm. The mean diameter of target arteries was 1.27 mm. The "critical angle" was 72-147 degrees. In all patients, there was satisfactory obliteration of the aneurysm. There were two cases of minor SAH post procedure. CONCLUSION: Utilizing the Circle of Willis for optimal stent placement in aneurysm remodeling is technically feasible but challenging. This technique can be performed successfully in patients with acute SAH. The procedural risk must be balanced against potential complications such as SAH.

Acute stroke patients treated with stent retrievers in carotid "T" occlusions have improved recanalization and outcome.

BACKGROUND: Recanalization rates and patient outcomes in acute occlusion of the carotid terminus have previously been poor. The use of stent-retrievers has resulted in better recanalization and patient outcomes. We sought to compare outcomes in patients treated with stent-retrievers to outcomes in older techniques. METHODS: We retrospectively compared a stent-retriever cohort to a historical cohort. We evaluated recanalization rates and good outcomes (defined as mRS < 2 at 30 days or 10 point drop in NIHSS). RESULTS: There were twenty patients treated with stent-retrievers versus nine without. The recanalization rate in patients treated with stent retrievers was significantly higher than that of other modalities (90% vs 33%, p=0.004). Good outcomes were significantly higher in the stent retriever cohort (70% vs 22%, p=0.041). CONCLUSION: The use of stent-retrievers in patients with carotid "T" occlusions shows promise in comparison to older techniques. A randomized trial comparing stent-retriever therapy to IV thrombolysis is warranted to determine the efficacy of this new generation of devices.