CT perfusion spot sign improves sensitivity for prediction of outcome compared with CTA and postcontrast CT

Added value of non-contrast CT and CT perfusion markers for prediction of intracerebral hemorrhage expansion and outcome

OBJECTIVES

To test the hypothesis that the combined analysis of non-contrast CT (NCCT) and CT perfusion (CTP) imaging markers improves prediction of hematoma expansion (HE) and outcome in intracerebral hemorrhage (ICH).

METHODS

Retrospective, single-center analysis of patients with primary ICH undergoing NCCT and CTP within 6 h from onset. NCCT images were assessed for the presence of intrahematomal hypodensity and shape irregularity. Perihematomal cerebral blood volume and spot sign were assessed on CTP. The main outcomes of the analysis were HE (growth > 6 mL and/or > 33%) and poor functional prognosis (90 days modified Rankin Scale 3-6). Predictors of HE and outcome were explored with logistic regression.

RESULTS

A total of 150 subjects were included (median age 68, 47.1% males) of whom 54 (36%) had HE and 52 (34.7%) had poor outcome. The number of imaging markers on baseline imaging was independently associated with HE (odds ratio 2.66, 95% confidence interval 1.70-4.17, p < 0.001) and outcome (odds ratio 1.64, 95% CI 1.06-2.56, p = 0.027). Patients with the simultaneous presence of all the four markers had the highest risk of HE and unfavorable prognosis (mean predicted probability of 91% and 79% respectively). The combined-markers analysis outperformed the sensitivity of the single markers analyzed separately. In particular, the presence of at least one marker identified patients with HE and poor outcome with 91% and 87% sensitivity respectively.

CONCLUSION

NCCT and CTP markers provide additional yield in the prediction of HE and ICH outcome.

KEY POINTS

• Perihematomal hypoperfusion is associated with hematoma expansion and poor outcome in acute intracerebral hemorrhage. • Non-contrast CT and CT perfusion markers improve prediction of hematoma expansion and unfavorable prognosis. • A multimodal CT protocol including CT perfusion will help the identification of patients at high risk of clinical deterioration and poor outcome.

Intracerebral hemorrhage markers on non-contrast computed tomography as predictors of the dynamic spot sign on CT perfusion and associations with hematoma expansion and outcome

PURPOSE

To assess the association between non-contrast computed tomography (NCCT) hematoma markers and the dynamic spot sign on computed tomography perfusion (CTP), and their associations with hematoma expansion, clinical outcome, and in-hospital mortality.

METHODS

Patients who presented with intracerebral hemorrhage (ICH) to a stroke center over an 18-month period and underwent baseline NCCT and CTP, and a follow-up NCCT within 24 h after the baseline scan were included. The initial and follow-up hematoma volumes were calculated. Two raters independently assessed the baseline NCCT for hematoma markers and concurrently assessed the CTP for the dynamic spot sign. Univariate and multivariate logistic regression analyses were performed to assess the association between the hematoma markers and the dynamic spot sign, adjusting for known ICH expansion predictors.

RESULTS

Eighty-five patients were included in our study and 55 patients were suitable for expansion analysis. Heterogeneous density was the only NCCT hematoma marker to be associated with the dynamic spot sign after multivariate analysis (odds ratio, 58.61; 95% confidence interval, 9.13-376.05; P < 0.001). The dynamic spot sign was present in 22 patients (26%) and significantly predicted hematoma expansion (odds ratio, 36.6; 95% confidence interval, 2.51-534.2; P = 0.008). All patients with a spot sign had a swirl sign. A co-located hypodensity and spot sign was significantly associated with in-hospital mortality (odds ratio, 6.17; 95% confidence interval, 1.09-34.78; P = 0.039).

CONCLUSION

Heterogeneous density and swirl sign are associated with the dynamic spot sign. The dynamic spot sign is a stronger predictor than NCCT hematoma markers of significant hematoma expansion. A co-located spot sign and hypodensity predicts in-hospital mortality.

From Spot Sign to Bleeding on the Spot: Classic and Original Signs of Expanding Primary Spontaneous Intracerebral Hematoma

Expansion of a primary spontaneous intracranial hemorrhage (PSICH) has become lately of increasing interest, especially after the emergence of its early predictors. However, these signs lacked sensitivity and specificity. The flood phenomenon, defined as a drastic increase in the size of a PSICH during the same magnetic resonance study, was first described in this paper based on the data of a university medical center in Lebanon. Moreover, further review of this data resulted in 205 studies with presumed diagnosis of primary spontaneous intracranial hemorrhage within the last 10 years, of which 29 exams showed typical predictors of hematoma expansion on computed tomography. The intended benefit of this observation is to draw the radiologists' attention towards minimal variations in the volume of the hematoma between the two extreme sequences of the same MRI study, in order to detect inconspicuous flood phenomena—a direct sign of hematoma expansion.

Utilization of Cerebral Blood Flow Study With Computed Tomography for Subdural Hematoma Management

Stroke is among the leading causes of death in the United States, and with our aging population, it will remain a pertinent obstacle in the acute setting. While the field of neuroradiology has advanced tremendously over the years, particularly in improving what we can visualize and quantify, the phrase “time is brain” yet dominates acute stroke management. Optimizing diagnostic protocols for suspected stroke requires a careful balance of data acquisition and speed, as well as taking into account available resources. We present a case of a middle-aged patient with notable risk factors for stroke presenting to the emergency department with altered mental status and suspected stroke. Radiography revealed a large subacute subdural hematoma (SDH) with a mild mass effect on the surface of the brain. The evaluation was supplemented by a computed tomography (CT) and perfusion cerebral blood flow (CBF) study indicating cortical ischemia with penumbra from the SDH compression. SDH evacuation was successfully performed, and patient recovery was achieved within the intensive care unit (ICU). Rapid data acquisition via CBF with CT imaging is crucial for guiding treatment decisions for SDHs. While protocols for ischemic stroke are well-established, SDH protocols are not studied. Thus, we discuss the value of a multimodal CT imaging approach, including CBF studies, in SDH evaluation.

Effect of Recombinant Activated Coagulation Factor VII on Hemorrhage Expansion Among Patients With Spot Sign-Positive Acute Intracerebral Hemorrhage: The SPOTLIGHT and STOP-IT Randomized Clinical Trials

Importance

Intracerebral hemorrhage (ICH) is a devastating stroke type that lacks effective treatments. An imaging biomarker of ICH expansion-the computed tomography (CT) angiography spot sign-may identify a subgroup that could benefit from hemostatic therapy.

Objective

To investigate whether recombinant activated coagulation factor VII (rFVIIa) reduces hemorrhage expansion among patients with spot sign-positive ICH.

Design, Setting, and Participants

In parallel investigator-initiated, multicenter, double-blind, placebo-controlled randomized clinical trials in Canada ("Spot Sign" Selection of Intracerebral Hemorrhage to Guide Hemostatic Therapy [SPOTLIGHT]) and the United States (The Spot Sign for Predicting and Treating ICH Growth Study [STOP-IT]) with harmonized protocols and a preplanned individual patient-level pooled analysis, patients presenting to the emergency department with an acute primary spontaneous ICH and a spot sign on CT angiography were recruited. Data were collected from November 2010 to May 2016. Data were analyzed from November 2016 to May 2017.

Interventions

Eligible patients were randomly assigned 80 μg/kg of intravenous rFVIIa or placebo as soon as possible within 6.5 hours of stroke onset.

Main Outcomes and Measures

Head CT at 24 hours assessed parenchymal ICH volume expansion from baseline (primary outcome) and total (ie, parenchymal plus intraventricular) hemorrhage volume expansion (secondary outcome). The pooled analysis compared hemorrhage expansion between groups by analyzing 24-hour volumes in a linear regression model adjusted for baseline volumes, time from stroke onset to treatment, and trial.

Results

Of the 69 included patients, 35 (51%) were male, and the median (interquartile range [IQR]) age was 70 (59-80) years. Baseline median (IQR) ICH volumes were 16.3 (9.6-39.2) mL in the rFVIIa group and 20.4 (8.6-32.6) mL in the placebo group. Median (IQR) time from CT to treatment was 71 (57-96) minutes, and the median (IQR) time from stroke onset to treatment was 178 (138-197) minutes. The median (IQR) increase in ICH volume from baseline to 24 hours was small in both the rFVIIa group (2.5 [0-10.2] mL) and placebo group (2.6 [0-6.6] mL). After adjustment, there was no difference between groups on measures of ICH or total hemorrhage expansion. At 90 days, 9 of 30 patients in the rFVIIa group and 13 of 34 in the placebo group had died or were severely disabled (P = .60).

Conclusions and Relevance

Among patients with spot sign-positive ICH treated a median of about 3 hours from stroke onset, rFVIIa did not significantly improve radiographic or clinical outcomes.

Trial Registration

ClinicalTrials.gov identifier: NCT01359202 and NCT00810888.

Haemostatic therapy in spontaneous intracerebral haemorrhage patients with high-risk of haematoma expansion by CT marker: a systematic review and meta-analysis of randomised trials

BACKGROUND AND PURPOSE

Current randomised controlled trials (RCTs) showed an uncertain benefit of haemostatic therapy on preventing haematoma expansion and improving the outcome in patients with intracerebral haemorrhage (ICH). This meta-analysis aims to systematically evaluate the effect of haemostatic agents on the prevention of haemorrhage growth in patients with high-risk spontaneous ICH predicted by CT signs in RCTs.

METHODS

A comprehensive search of PubMed, EMBASE and Cochrane library from 1 January 2005 to 30 June 2021 was conducted. RCTs that compared haemostatic agents with placebo for the treatment of spontaneous patients with ICH with high-risk haemorrhage growth were included. The primary endpoint was haematoma expansion at 24 hours. Other major endpoints of interest included 90-day functional outcome and mortality.

RESULTS

The meta-analysis included four RCTs that randomised 2666 patients with ICH with high-risk haemorrhage growth. Haemostatic therapy reduced the rate of haematoma expansion at a marginally statistically significant level when compared with placebo (OR 0.84; 95% CI 0.70 to 1.00; p=0.051). Subgroup analysis for patients with black hole sign on CT revealed a significant reduction of haematoma expansion with haemostatic therapy (OR 0.61; 95% CI 0.39 to 0.94; p=0.03). However, both the primary analysis and subgroup analyses showed that haemostatic therapy could not reduce the rate of poor functional outcome (modified Rankin Scale >3) or death.

CONCLUSIONS

Haemostatic therapy showed a marginally significant benefit in reducing early haematoma expansion in patients with high-risk spontaneous ICH predicted by markers on CT scan. However, no significant improvement in functional outcome or reduction of mortality was observed.

Tranexamic acid for acute intracerebral haemorrhage growth based on imaging assessment (TRAIGE): a multicentre, randomised, placebo-controlled trial

BACKGROUND

Studies show tranexamic acid can reduce the risk of death and early neurological deterioration after intracranial haemorrhage. We aimed to assess whether tranexamic acid reduces haematoma expansion and improves outcome in intracerebral haemorrhage patients susceptible to haemorrhage expansion.

METHODS

We did a prospective, double-blind, randomised, placebo-controlled trial at 10 stroke centres in China. Acute supratentorial intracerebral haemorrhage patients were eligible if they had indication of haemorrhage expansion on admission imaging (eg, spot sign, black hole sign or blend sign), and were treatable within 8 hours of symptom onset. Patients were randomly assigned (1:1) to receive either tranexamic acid or a matching placebo. The primary outcome was intracerebral haematoma growth (>33% relative or >6 mL absolute) at 24 hours. Clinical outcomes were assessed at 90 days.

RESULTS

Of the 171 included patients, 124 (72.5%) were male, and the mean age was 55.9±11.6 years. 89 patients received tranexamic acid and 82 received placebo. The primary outcome did not differ significantly between the groups: 36 (40.4%) patients in the tranexamic acid group and 34 (41.5%) patients in the placebo group had intracranial haemorrhage growth (OR 0.96, 95% CI 0.52 to 1.77, p=0.89). The proportion of death was lower in the tranexamic acid treatment group than placebo group (8.1% vs 10.0%), but there were no significant differences in secondary outcomes including absolute intracranial haemorrhage growth, death and dependency.

CONCLUSIONS

Among patients susceptible to haemorrhage expansion treated within 8 hours of stroke onset, tranexamic acid did not significantly prevent intracerebral haemorrhage growth. Larger studies are needed to assess safety and efficacy of tranexamic acid in intracerebral haemorrhage patients.

Hemorrhagic stroke

Hemorrhagic stroke comprises about 20% of all strokes, with intracerebral hemorrhage (ICH) being the most common type. Frequency of ICH is increased where hypertension is untreated. ICH in particularly has a disproportionately high risk of early mortality and long-term disability. Until recently, there has been a paucity of randomized controlled trials (RCTs) to provide evidence for the efficacy of various commonly considered interventions in ICH, including acute blood pressure management, coagulopathy reversal, and surgical hematoma evacuation. Evidence-based guidelines do exist for ICH and these form the basis for a framework of care. Current approaches emphasize control of extremely high blood pressure in the acute phase, rapid reversal of vitamin K antagonists, and surgical evacuation of cerebellar hemorrhage. Lingering questions, many of which are the topic of ongoing clinical research, include optimizing individual blood pressure targets, reversal strategies for newer anticoagulant medications, and the role of minimally invasive surgery. Risk stratification models exist, which derive from findings on clinical exam and neuroimaging, but care should be taken to avoid a self-fulfilling prophecy of poor outcome from limiting treatment due to a presumed poor prognosis. Cerebral venous thrombosis is an additional subtype of hemorrhagic stroke that has a unique set of causes, natural history, and treatment and is discussed as well.

Hematoma Expansion in Intracerebral Hemorrhage: An Update on Prediction and Treatment

Intracerebral hemorrhage (ICH) is the most lethal type of stroke, but there is no specific treatment. After years of effort, neurologists have found that hematoma expansion (HE) is a vital predictor of poor prognosis in ICH patients, with a not uncommon incidence ranging widely from 13 to 38%. Herein, the progress of studies on HE after ICH in recent years is updated, and the topics of definition, prevalence, risk factors, prediction score models, mechanisms, treatment, and prospects of HE are covered in this review. The risk factors and prediction score models, including clinical, imaging, and laboratory characteristics, are elaborated in detail, but limited by sensitivity, specificity, and inconvenience to clinical practice. The management of HE is also discussed from bench work to bed practice. However, the upmost problem at present is that there is no treatment for HE proven to definitely improve clinical outcomes. Further studies are needed to identify more accurate predictors and effective treatment to reduce HE.

Correlation between Spot Sign and Intracranial Hemorrhage Expansion on Dual-Phase CT Angiography

Purpose: Expansion of intracranial hemorrhage (ICH) is an important predictor of poor clinical outcome. ICH expansion can be predicted with a spot sign on computed tomographic angiography (CTA). We aimed to evaluate the correlation between spot signs on CTA and ICH expansion on dual-phase CTA. Methods: Patients with spontaneous ICH between January 2017 and April 2019 who underwent an initial CT, dual-phase CTA, and a subsequent CT were retrospectively identified. ICH expansion was defined as volume growth of >33% or >6 mL. We analyzed the presence and change in size of the spot sign in the first phase and second phase CTA. Also, we divided the morphological status of the spot sign, such as a dot-like lesion or linear contrast extravasation, in the first and second phase CTA. Results: A total of 206 patients, including 38 (18.5%) with ICH expansion and 45 (21.8%) with a spot sign, qualified for analysis. Of patients with a spot sign, 26 (57.8%) had ICH expansion on subsequent CT. Increased size of a spot sign in second-phase CTA was more frequent in the ICH expansion group than in the no-expansion group (96.2% vs. 52.6%, p < 0.001). First visualization of a spot sign in the second phase was more common in the no-expansion group than in the ICH expansion group (47.4% vs. 3.8%, p < 0.001). The morphological patterns of a spot sign between the two groups were not significantly different. Conclusion: Spot signs on dual-phase CTA have different sizes and morphological patterns. Increased size of a spot sign in the second phase of CTA can help identify patients at risk for ICH expansion.

Dual-Phase Computed Tomography Angiography Enhances Detection of Contrast Extravasation in Subarachnoid Hemorrhage

BACKGROUND

Contrast-enhanced computed tomography angiography (CTA) can be used to detect contrast extravasation in intracerebral hemorrhage. However, investigation for contrast extravasation in subarachnoid hemorrhage (SAH) is insufficient. We evaluated the efficacy of dual-phase CTA to improve evaluation of contrast extravasation in SAH.

METHODS

We retrospectively evaluated 35 patients with SAH who underwent contrast-enhanced dual-phase CTA within 24 hours from onset. The second-phase scan was performed 8 or 15 seconds following the usual CTA. The frequency of contrast extravasation was compared between phases. We also recorded the time from onset, coma level, interventional treatment, and early mortality.

RESULTS

Of 35 patients (22.9%) with SAH, 8 showed contrast extravasation in the second phase compared with 3 in the first phase. Contrast extravasation was correlated with clinical coma level (P < 0.05), and all contrast extravasation was found within 6 hours from onset. Early mortality, treatment decision, and hematoma distribution type did not correlate with existence of contrast extravasation. We also observed 4 cases of secondary subpial hematoma due to SAH, with 3 showing extravasation in both phases.

CONCLUSIONS

Dual-phase CTA with a short interval enhances detection frequency of contrast extravasation in SAH and might be a better evaluation tool for SAH.

Iodine Sign as a Novel Predictor of Hematoma Expansion and Poor Outcomes in Primary Intracerebral Hemorrhage Patients

Background and Purpose- The aim of the study was to investigate the utility of iodine contrast agent leakage (the iodine sign) analyzed by Gemstone spectral imaging in early hematoma formation compared with that of the spot sign for predicting early hematoma expansion (HE) and poor functional outcomes. Methods- From 2014 to 2017, 91 patients with spontaneous intracerebral hemorrhage who underwent spectral computed tomography angiography within 6 hours of spontaneous intracerebral hemorrhage onset were prospectively included in our study. We defined a positive iodine sign as tiny enhancing foci within the hematoma on Gemstone spectral imaging and an iodine concentration inside the foci of >7.82 (100 µg/mL). Univariate and multivariate logistical regression analyses were performed to assess risk factors for HE, and the predictive value of HE was analyzed. Results- Positive spot and iodine signs were present in 38.5% (35/91) and 57.1% (52/91) of the patients, respectively. Using multivariate analysis, the iodine sign independently predicted HE (odds ratio, 53.67; 95% CI, 11.88-242.42; P<0.001) and had a higher sensitivity (91.5% versus 63.8%), negative predictive value (89.7% versus 69.9%), and accuracy (85.7% versus 75.8%) for detecting HE than the spot sign. The iodine sign, but not the spot sign, was significantly related to poor functional outcomes (severely disabled and vegetative state) in all patients (χ²=29.97; P<0.001). Conclusions- The iodine sign is a reliable and sensitive marker for predicting HE and poor functional outcomes. Clinical Trial Registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT02625948.

Intracerebral haemorrhage: current approaches to acute management

Acute spontaneous intracerebral haemorrhage is a life-threatening illness of global importance, with a poor prognosis and few proven treatments. As a heterogeneous disease, certain clinical and imaging features help identify the cause, prognosis, and how to manage the disease. Survival and recovery from intracerebral haemorrhage are related to the site, mass effect, and intracranial pressure from the underlying haematoma, and by subsequent cerebral oedema from perihaematomal neurotoxicity or inflammation and complications from prolonged neurological dysfunction. A moderate level of evidence supports there being beneficial effects of active management goals with avoidance of early palliative care orders, well-coordinated specialist stroke unit care, targeted neurointensive and surgical interventions, early control of elevated blood pressure, and rapid reversal of abnormal coagulation.

Added value of delayed computed tomography angiography in primary intracranial hemorrhage and hematoma size for predicting spot sign

Background The computed tomography angiography (CTA) spot sign represents active contrast extravasation within acute primary intracerebral hemorrhage (ICH) and is an independent predictor of hematoma expansion (HE) and poor clinical outcomes. The spot sign could be detected on first-pass CTA (fpCTA) or delayed CTA (dCTA). Purpose To investigate the additional benefits of dCTA spot sign in primary ICH and hematoma size for predicting spot sign. Material and Methods This is a retrospective study of 100 patients who underwent non-contrast CT (NCCT) and CTA within 24 h of onset of primary ICH. The presence of spot sign on fpCTA or dCTA, and hematoma size on NCCT were recorded. The spot sign on fpCTA or dCTA for predicting significant HE, in-hospital mortality, and poor clinical outcomes (mRS ≥ 4) are calculated. The hematoma size for prediction of CTA spot sign was also analyzed. Results Only the spot sign on dCTA could predict high risk of significant HE and poor clinical outcomes as on fpCTA ( P < 0.05). With dCTA, there is increased sensitivity and negative predictive value (NPV) for predicting significant HE, in-hospital mortality, and poor clinical outcomes. The XY value (product of the two maximum perpendicular axial dimensions) is the best predictor (area under the curve [AUC] = 0.82) for predicting spot sign on fpCTA or dCTA in the absence of intraventricular and subarachnoid hemorrhage. Conclusion This study clarifies that dCTA imaging could improve predictive performance of CTA in primary ICH. Furthermore, the XY value is the best predictor for CTA spot sign.

The "Blush" Sign on Computed Tomography Angiography is an Independent Predictor of Hematoma Progression in Primary Hypertensive Hemorrhage

BACKGROUND AND PURPOSE

Hypertension is an important etiology of intracerebral hemorrhage (ICH) in neurosurgical practice. Contrast extravasation on computed tomography angiography, known as the "spot sign", has been described as an independent predictor of hematoma progression and clinical deterioration. However, its role in hypertensive ICH alone has not been determined and is the primary aim of this study.

MATERIALS AND METHODS

A retrospective review was carried out of patients with hypertensive ICH admitted to our institution between May 2014 and December 2016. Evaluation of the neuroimaging studies of these patients revealed two distinct morphologies, "spot" and "blush" sign. These distinct signs and covariates were tested for association with hematoma expansion and mortality using multivariate logistic regression. The accuracy of the "spot" and "blush" signs as predictors of hematoma expansion and mortality was determined using receiver-operator characteristic (ROC) analysis.

RESULTS

A total of 54 patients were identified as hypertensive ICH during the study period. "spot" sign was observed in 11 (20.4%) of the study population. Contrast extravasation (blush-sign) was seen in 7 (14.8%) patients. The "blush" was an independent predictor of hematoma expansion (odds ratio [OR] 6.052; confidence interval [CI] 1.036-15.945 [P = .012]) and mortality (OR 3.305; CI 1.240-25.414 [P = .032]). With ROC analysis, the "blush" sign was found to have a better predictive value for significant hematoma expansion (area under the curve [AUC]: .795) than the spot sign (AUC: .432).

CONCLUSION

The "blush" sign has better accuracy for predicting hematoma expansion in hypertensive ICH and could be used to risk stratify these patients for early therapeutic interventions.

Predictive Value of CTA Spot Sign on Hematoma Expansion in Intracerebral Hemorrhage Patients

Hematoma expansion (HE) occurs in approximately one-third of patients with intracerebral hemorrhage and leads to high rates of mortality and morbidity. Currently, contrast extravasation within hematoma, termed the spot sign on computed tomography angiography (CTA), has been identified as a strong independent predictor of early hematoma expansion. Past studies indicate that the spot sign is a dynamic entity and is indicative of active hemorrhage. Furthermore, to enhance the spot sign's accuracy of predicting HE, spot parameters observed on CTA or dynamic CTA were used for its quantification. In addition, spot signs detected on multiphase CTA and dynamic CTA are shown to have higher sensitivity and specificity when compared with simple standardized spot sign detection in recent studies. Based on the spot sign, novel methods such as leakage sign and rate of contrast extravasation were explored to redefine HE prediction in combination with clinical characteristics and spot sign on CTA to assist clinical judgment. The spot sign is an accepted independent predictor of active hemorrhage and is used in both secondary intracerebral hemorrhage and the process of surgical assessment for hemorrhagic risk in patients with ischemic stroke. Spot sign predicts patients at high risk for hematoma expansion.

Predictors of hematoma expansion predictors after intracerebral hemorrhage

Despite years of effort, intracerebral hemorrhage (ICH) remains the most devastating form of stroke with more than 40% 30-day mortality worldwide. Hematoma expansion (HE), which occurs in one third of ICH patients, is strongly predictive of worse prognosis and potentially preventable if high-risk patients were identified in the early phase of ICH. In this review, we summarize data from recent studies on HE prediction and classify those potential indicators into four categories: clinical (severity of consciousness disturbance; blood pressure; blood glucose at and after admission); laboratory (hematologic parameters of coagulation, inflammation and microvascular integrity status), radiographic (interval time from ICH onset; baseline volume, shape and density of hematoma; intraventricular hemorrhage; especially the spot sign and modified spot sign) and integrated predictors (9-point or 24-point clinical prediction algorithm and PREDICT A/B). We discuss those predictors’ underlying pathophysiology in HE and present opportunities to develop future therapeutic strategies.

Negative spot sign in primary intracerebral hemorrhage: potential impact in reducing imaging

Intracerebral hemorrhage (ICH) is one of the most devastating and costly diagnoses in the USA. ICH is a common diagnosis, accounting for 10-15 % of all strokes and affecting 20 out of 100,000 people. The CT angiography (CTA) spot sign, or contrast extravasation into the hematoma, is a reliable predictor of hematoma expansion, clinical deterioration, and increased mortality. Multiple studies have demonstrated a high negative predictive value (NPV) for ICH expansion in patients without spot sign. Our aim is to determine the absolute NPV of the spot sign and clinical characteristics of patients who had ICH expansion despite the absence of a spot sign. This information may be helpful in the development of a cost effective imaging protocol of patients with ICH. During a 3-year period, 204 patients with a CTA with primary intracerebral hemorrhage were evaluated for subsequent hematoma expansion during their hospitalization. Patients with intraventricular hemorrhage were excluded. Clinical characteristics and antithrombotic treatment on admission were noted. The number of follow-up NCCT was recorded. Of the resulting 123 patients, 108 had a negative spot sign and 7 of those patients subsequently had significant hematoma expansion, 6 of which were on antithrombotic therapy. The NPV of the CTA spot sign was calculated at 0.93. In patients without antithrombotic therapy, the NPV was 0.98. In summary, the negative predictive value of the CTA spot sign for expansion of ICH, in the absence of antithrombotic therapy and intraventricular hemorrhage (IVH) on admission, is very high. These results have the potential to redirect follow-up imaging protocols and reduce cost.

Timing of Occurrence Is the Most Important Characteristic of Spot Sign

BACKGROUND AND PURPOSE

Most previous studies have used single-phase computed tomographic angiography to detect the spot sign, a marker for hematoma expansion (HE) in spontaneous intracerebral hemorrhage. We investigated whether defining the spot sign based on timing on perfusion computed tomography (CTP) would improve its specificity for predicting HE.

METHODS

We prospectively enrolled supratentorial spontaneous intracerebral hemorrhage patients who underwent CTP within 6 hours of onset. Logistic regression was performed to assess the risk factors for HE and poor outcome. Predictive performance of individual CTP spot sign characteristics were examined with receiver operating characteristic analysis.

RESULTS

Sixty-two men and 21 women with spontaneous intracerebral hemorrhage were included in this analysis. Spot sign was detected in 46% (38/83) of patients. Receiver operating characteristic analysis indicated that the timing of spot sign occurrence on CTP had the greatest area under receiver operating characteristic curve for HE (0.794; 95% confidence interval, 0.630-0.958; P=0.007); the cutoff time was 23.13 seconds. On multivariable analysis, the presence of early-occurring spot sign (ie, spot sign before 23.13 seconds) was an independent predictor not only of HE (odds ratio=28.835; 95% confidence interval, 6.960-119.458; P<0.001), but also of mortality at 3 months (odds ratio =22.377; 95% confidence interval, 1.773-282.334; P=0.016). Moreover, the predictive performance showed that the redefined early-occurring spot sign maintained a higher specificity for HE compared with spot sign (91% versus 74%).

CONCLUSIONS

Redefining the spot sign based on timing of contrast leakage on CTP to determine early-occurring spot sign improves the specificity for predicting HE and 3-month mortality. The use of early-occurring spot sign could improve the selection of ICH patients for potential hemostatic therapy.

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 (χ 2 statistic, 11.5; P =0.175), whereas the 9-point score demonstrated poor calibration (χ 2 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.

The accuracy of spot sign in predicting hematoma expansion after intracerebral hemorrhage: a systematic review and meta-analysis

Purpose

The role of spot sign on computed tomography angiography (CTA) for predicting hematoma expansion (HE) after primary intracerebral hemorrhage (ICH) has been the focus of many studies. Our study sought to evaluate the predictive accuracy of spot signs for HE in a meta-analytic approach.

Materials and Methods

The database of Pubmed, Embase, and the Cochrane Library were searched for eligible studies. Researches were included if they reported data on HE in primary ICH patients, assessed by spot sign on first-pass CTA. Studies with additional data of second-pass CTA, post-contrast CT (PCCT) and CT perfusion (CTP) were also included.

Results

18 studies were pooled into the meta-analysis, including 14 studies of first-pass CTA, and 7 studies of combined CT modalities. In evaluating the accuracy of spot sign for predicting HE, studies of first-pass CTA showed that the sensitivity was 53% (95% CI, 49%–57%) with a specificity of 88% (95% CI, 86%–89%). The pooled positive likelihood ratio (PLR) was 4.70 (95% CI, 3.28–6.74) and the negative likelihood ratio (NLR) was 0.44 (95% CI, 0.34–0.58). For studies of combined CT modalities, the sensitivity was 73% (95% CI, 67%–79%) with a specificity of 88% (95% CI, 86%–90%). The aggregated PLR was 6.76 (95% CI, 3.70–12.34) and the overall NLR was 0.17 (95% CI 0.06–0.48).

Conclusions

Spot signs appeared to be a reliable imaging biomarker for HE. The additional detection of delayed spot sign was helpful in improving the predictive accuracy of early spot signs. Awareness of our results may impact the primary ICH care by providing supportive evidence for the use of combined CT modalities in detecting spot signs.

Spot sign on 90-second delayed computed tomography angiography improves sensitivity for hematoma expansion and mortality: prospective study

BACKGROUND AND PURPOSE

The computed tomography angiography (CTA) spot sign is a validated biomarker for poor outcome and hematoma expansion in intracerebral hemorrhage. The spot sign has proven to be a dynamic entity, with multimodal imaging proving to be of additional value. We investigated whether the addition of a 90-second delayed CTA acquisition would capture additional intracerebral hemorrhage patients with the spot sign and increase the sensitivity of the spot sign.

METHODS

We prospectively enrolled consecutive intracerebral hemorrhage patients undergoing first pass and 90-second delayed CTA for 18 months at a single academic center. Univariate and multivariate logistic regression were performed to assess clinical and neuroimaging covariates for relationship with hematoma expansion and mortality.

RESULTS

Sensitivity of the spot sign for hematoma expansion on first pass CTA was 55%, which increased to 64% if the spot sign was present on either CTA acquisition. In multivariate analysis the spot sign presence was associated with significant hematoma expansion: odds ratio, 17.7 (95% confidence interval, 3.7-84.2; P=0.0004), 8.3 (95% confidence interval, 2.0-33.4; P=0.004), and 12.0 (95% confidence interval, 2.9-50.5; P=0.0008) if present on first pass, delayed, or either CTA acquisition, respectively. Spot sign presence on either acquisitions was also significant for mortality.

CONCLUSIONS

We demonstrate improved sensitivity for predicting hematoma expansion and poor outcome by adding a 90-second delayed CTA, which may enhance selection of patients who may benefit from hemostatic therapy.

Prevalence and diagnostic performance of computed tomography angiography spot sign for intracerebral hematoma expansion depend on scan timing

INTRODUCTION

The computed tomography angiography (CTA) spot sign correlates with intracerebral hemorrhage (ICH) expansion; however, various diagnostic performances for hematoma expansion, especially in sensitivity, have been reported. We aimed to assess the impact of scan timing of CTA on the diagnostic performance of the CTA spot sign for ICH expansion in two different arterial phases within patients.

METHODS

Eighty-three consecutive patients with primary ICH who received two sequential CTAs were recruited. Two neuroradiologists reviewed CTAs for CTA spot signs, while one reviewed initial and follow-up non-contrast CT for measuring ICH volume. The time interval between two phases was then calculated, and the diagnostic performance of CTA spot sign in each phase was evaluated.

RESULTS

CTA spot signs were observed in 20/83 (24.1 %) patients in the early phase and 44/83 (53.0%) patients in the late phase. The mean time interval between the two phases was 12.7 s. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy for hematoma progression of CTA spot sign were 48.1, 87.5, 65.0, 77.8, and 74.7%, respectively, in early phase and 92.6, 66.1, 56.8, 94.9, and 74.7%, respectively, in late phase. The CTA spot sign was significantly associated with ICH expansion in early (P < 0.001) and late (P < 0.00001) phases (Pearson's chi-square test).

CONCLUSION

A mere 10-s difference in scan timing could make a difference on prevalence and diagnostic performance of the CTA spot sign, suggesting a need for the standardization of the CTA protocol to generalize the approach for effective clinical application.

Accuracy of the spot sign on computed tomography angiography as a predictor of haematoma enlargement after acute spontaneous intracerebral haemorrhage: a systematic review

BACKGROUND

A common early complication of intracerebral haemorrhage (ICH) is haematoma enlargement (HE), a strong independent predictor of a poor outcome. Therapeutic options to limit haematoma progression are currently scarce. Haemostatic therapy may be effective in patients with ICH, but it carries the risk of thromboembolic events in unselected patients. Accurate patient selection would, therefore, be of key importance for delivering potentially successful therapeutic strategies. Currently, there is no gold standard to accurately predict HE. The presence of contrast extravasation within the haematoma on computed tomography angiography (CTA), the 'spot sign', has been reported in several studies and seems a particularly promising marker but lacks a standardised evaluation so far.

SUMMARY

We conducted a systematic review of published data to address the research question: In adults with acute spontaneous ICH, how accurately does the spot sign predict HE on follow-up imaging and thus poor functional outcome or mortality? We searched PubMed and Embase databases (from 1980 to May 2012), using a highly sensitive search strategy and including all studies involving adult patients with spontaneous ICH evaluated with CTA and follow-up CT scans, reporting any measure of clinical outcome, and reporting or allowing calculation of accuracy measures of the spot sign in predicting HE and clinical outcome. Baseline characteristics, accuracy measures and effect measures, as well as bias assessment, were reported according to PRISMA recommendations. The quality of the studies was appraised using an adapted version of the REMARK reporting recommendations. From 259 potentially relevant studies, we finally selected 6 studies (1 of them was a multicentre cohort study) covering a total of 709 patients. Studies varied substantially in terms of size, methodological quality, definitions of terms, outcomes selected and results. In particular, definition of the spot sign was not consistent in all studies. Furthermore, the only outcome measure consistently available was HE, while definitions and analyses of clinical outcomes seemed not adequate. Lastly, the choice of candidate variables for univariate and multivariate analyses did not include all determinants of HE and poor functional outcome. High heterogeneity was demonstrated (I(2): 94% for HE) with substantial potential of bias.

KEY MESSAGES

Studies of the spot sign are diverse and therefore complex to interpret. Our research question could not be answered due to heterogeneity and potential of bias in the selected studies. Further appropriately powered studies using standardised definitions and taking all predictors of HE and poor clinical outcome into account are required for a proper clinical implementation.

Dynamic characterization of the CT angiographic 'spot sign'

Background and purpose

Standard (static) CT angiography is used to identify the intracerebral hemorrhage (ICH) spot sign. We used dynamic CT-angiography to describe spot sign characteristics and measurement parameters over 60-seconds of image acquisition.

Methods

We prospectively identified consecutive patients presenting with acute ICH within 4.5 hours of symptom onset, and collected whole brain dynamic CT-angiography (dCTA). Spot parameters (earliest appearance, duration, maximum Hounsfield unit (HU), time to maximum HU, time to spot diagnostic definition, spot volume and hematoma volumes) were measured using volumetric analysis software.

Result

We enrolled 34 patients: three were excluded due to secondary causes of ICH. Of the remaining 31 patients there were 18 females (58%) with median age 70 (range 47–86) and baseline hematoma volume 33 ml (range 0.7–103 ml). Positive dCTA spot sign was present in 13 patients (42%) visualized as an expanding 3-dimensional structure temporally evolving its morphology over the scan period. Median time to spot appearance was 21 s (range 15–35 seconds). This method allowed tracking of spots evolution until the end of venous phase (active extravasation) with median duration of 39 s (range 25–45 seconds). The average density and time to maximum density was 204HU and 30.8 s (range 23–31 s) respectively. Median time to spot diagnosis was 20.8 s using either 100 or 120HU definitions.

Conclusion

Dynamic CTA allows a 3-dimensional assessment of spot sign formation during acute ICH, and captured higher spot sign prevalence than previously reported. This is the first study to describe and quantify spot sign characteristics using dCTA; these can be used in ongoing and upcoming ICH studies.

Evolution of Computed Tomography Angiography Spot Sign Is Consistent With a Site of Active Hemorrhage in Acute Intracerebral Hemorrhage

Background and Purpose—

CT angiography spot sign predicts hematoma expansion in patients with acute intracerebral hemorrhage (ICH). The spot sign may represent a site of active extravasation, a locus of arrested hemorrhage forming fibrin globes, or represent associated epiphenomena such as hypertensive microaneurysms. We sought to describe the evolution of spot signs over 60 seconds in acute ICH using dynamic CT angiography and determine whether they grow and diffuse into the hematoma as would be expected with active extravasation.

Methods—

We prospectively identified consecutive patients presenting with spontaneous ICH <6 hours from symptom onset that completed dynamic CT angiography imaging over a 60-second acquisition protocol. We determined spot positivity, quantified spot volumes, and then used repeated-measures ANOVA to assess changes in spot volume over time.

Results—

We collected data on 35 patients; 13 of 35 (37%) patients were spot-positive. Spot-positive patients had larger median ICH volume compared with spot-negative patients (median 10.7 versus 49.2 mL; P =0.007). Maximal spot sign volumes ranged from 0.02 to 2.8 mL (median 0.17 mL). Spot sign volumes increased significantly with time ( P <0.001) and seemed to disperse into the hematoma in all cases. Three of 13 (23%) spot-positive patients presented with 2 distinct spot signs, but the remaining patients either had only 1 spot sign or different contiguous components of an irregularly shaped spot sign.

Conclusions—

In this dynamic CT angiography study of ICH, spot signs evolve consistent with sites of active extravasation.

Multicenter Accuracy and Interobserver Agreement of Spot Sign Identification in Acute Intracerebral Hemorrhage

Background and Purpose—

Rapid, accurate, and reliable identification of the computed tomography angiography spot sign is required to identify patients with intracerebral hemorrhage for trials of acute hemostatic therapy. We sought to assess the accuracy and interobserver agreement for spot sign identification.

Methods—

A total of 131 neurology, emergency medicine, and neuroradiology staff and fellows underwent imaging certification for spot sign identification before enrolling patients in 3 trials targeting spot-positive intracerebral hemorrhage for hemostatic intervention (STOP-IT, SPOTLIGHT, STOP-AUST). Ten intracerebral hemorrhage cases (spot-positive/negative ratio, 1:1) were presented for evaluation of spot sign presence, number, and mimics. True spot positivity was determined by consensus of 2 experienced neuroradiologists. Diagnostic performance, agreement, and differences by training level were analyzed.

Results—

Mean accuracy, sensitivity, and specificity for spot sign identification were 87%, 78%, and 96%, respectively. Overall sensitivity was lower than specificity ( P <0.001) because of true spot signs incorrectly perceived as spot mimics. Interobserver agreement for spot sign presence was moderate ( k =0.60). When true spots were correctly identified, 81% correctly identified the presence of single or multiple spots. Median time needed to evaluate the presence of a spot sign was 1.9 minutes (interquartile range, 1.2–3.1 minutes). Diagnostic performance, interobserver agreement, and time needed for spot sign evaluation were similar among staff physicians and fellows.

Conclusions—

Accuracy for spot identification is high with opportunity for improvement in spot interpretation sensitivity and interobserver agreement particularly through greater reliance on computed tomography angiography source data and awareness of limitations of multiplanar images. Further prospective study is needed.

Imaging recommendations for acute stroke and transient ischemic attack patients: A joint statement by the American Society of Neuroradiology, the American College of Radiology, and the Society of NeuroInterventional Surgery

SUMMARY

Stroke is a leading cause of death and disability worldwide. Imaging plays a critical role in evaluating patients suspected of acute stroke and transient ischemic attack, especially before initiating treatment. Over the past few decades, major advances have occurred in stroke imaging and treatment, including Food and Drug Administration approval of recanalization therapies for the treatment of acute ischemic stroke. A wide variety of imaging techniques has become available to assess vascular lesions and brain tissue status in acute stroke patients. However, the practical challenge for physicians is to understand the multiple facets of these imaging techniques, including which imaging techniques to implement and how to optimally use them, given available resources at their local institution. Important considerations include constraints of time, cost, access to imaging modalities, preferences of treating physicians, availability of expertise, and availability of endovascular therapy. The choice of which imaging techniques to employ is impacted by both the time urgency for evaluation of patients and the complexity of the literature on acute stroke imaging. Ideally, imaging algorithms should incorporate techniques that provide optimal benefit for improved patient outcomes without delaying treatment.