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

External validation study on the value of deep learning algorithm for the prediction of hematoma expansion from noncontrast CT scans

Background

Hematoma expansion is an independent predictor of patient outcome and mortality. The early diagnosis of hematoma expansion is crucial for selecting clinical treatment options. This study aims to explore the value of a deep learning algorithm for the prediction of hematoma expansion from non-contrast computed tomography (NCCT) scan through external validation.

Methods

102 NCCT images of hypertensive intracerebral hemorrhage (HICH) patients diagnosed in our hospital were retrospectively reviewed. The initial computed tomography (CT) scan images were evaluated by a commercial Artificial Intelligence (AI) software using deep learning algorithm and radiologists respectively to predict hematoma expansion and the corresponding sensitivity, specificity and accuracy of the two groups were calculated and compared. Comparisons were also conducted among gold standard hematoma expansion diagnosis time, AI software diagnosis time and doctors’ reading time.

Results

Among 102 HICH patients, the sensitivity, specificity, and accuracy of hematoma expansion prediction in the AI group were higher than those in the doctor group(80.0% vs 66.7%, 73.6% vs 58.3%, 75.5% vs 60.8%), with statistically significant difference (p < 0.05). The AI diagnosis time (2.8 ± 0.3 s) and the doctors’ diagnosis time (11.7 ± 0.3 s) were both significantly shorter than the gold standard diagnosis time (14.5 ± 8.8 h) (p < 0.05), AI diagnosis time was significantly shorter than that of doctors (p < 0.05).

Conclusions

Deep learning algorithm could effectively predict hematoma expansion at an early stage from the initial CT scan images of HICH patients after onset with high sensitivity and specificity and greatly shortened diagnosis time, which provides a new, accurate, easy-to-use and fast method for the early prediction of hematoma expansion.

Variation in medical management and neurosurgical treatment of patients with supratentorial spontaneous intracerebral haemorrhage

Introduction

The role of surgery in spontaneous intracerebral haemorrhage (sICH) remains controversial. This leads to variation in the percentage of patients who are treated with surgery between countries.

Patients and methods

We sent an online survey to all neurosurgeons (n = 140) and to a sample of neurologists (n = 378) in Dutch hospitals, with questions on management in supratentorial sICH in general, and on treatment in six patients, to explore current variation in medical and neurosurgical management. We assessed patient and haemorrhage characteristics influencing treatment decisions.

Results

Twenty-nine (21%) neurosurgeons and 92 (24%) neurologists responded. Prior to surgery, neurosurgeons would more frequently administer platelet-transfusion in patients on clopidogrel (64% versus 13%; p = 0.000) or acetylsalicylic acid (61% versus 11%; p = 0.000) than neurologists. In the cases, neurosurgeons and neurologists were similar in their choice for surgery as initial treatment (24% and 31%; p = 0.12), however variation existed amongst physicians in specific cases. Neurosurgeons preferred craniotomy with haematoma evacuation (74%) above minimally-invasive techniques (5%). Age, Glasgow Coma Scale score and ICH location were important factors influencing decisions on treatment for neurosurgeons and neurologists. 69% of neurosurgeons and 80% of neurologists would randomise patients in a trial evaluating the effect of minimally-invasive surgery on functional outcome.

Discussion

Our results reflect the lack of evidence about the right treatment strategy in patients with sICH.

Conclusion

New high quality evidence is needed to guide treatment decisions for patients with ICH. The willingness to randomise patients into a clinical trial on minimally-invasive surgery, contributes to the feasibility of such studies in the future.

Different criteria for defining "spot sign" in intracerebral hemorrhage show different abilities to predict hematoma expansion and clinical outcomes: a systematic review and meta-analysis

The "spot sign" is a well-known radiological marker used for predicting hematoma expansion and clinical outcomes in patients with intracerebral hemorrhage (ICH). We performed a meta-analysis to assess the predictive accuracy of spot sign, depending on the criteria used to identify them.We conducted a systematic review of clinical studies that clearly stated their definition of spot sign and that were indexed in the Cochrane Library, MEDLINE, EMBASE, and the China National Knowledge Infrastructure databases. We collected data on computed tomography (CT) parameters, spot sign diagnostic criteria, hematoma expansion, and clinical outcomes.Based on the eligibility criteria, we included 17 studies in this systematic review. CT imaging modality, type, time from symptom onset to CT, time from contrast infusion to scan, slice thickness, tube current, and tube electric discharge showed variation across studies. Three different definitions of the spot sign were applied: (1) a hyperdense spot within the hematoma; (2) one or more focal areas/regions of contrast pooling of any size and morphology that occurred within a hemorrhage, were discontinuous from the normal or abnormal vasculature adjacent to the hemorrhage, and showed an attenuation rate ≥ 120 UH; or (3) serpiginous or spot-like contrast density on CTA images that occurred within the hematoma margin, showed twice the density of the hematoma background, and did not contact vessels outside the hematoma. Three definitions for the spot sign were identified, all of which were associated with hematoma expansion, mortality, and unfavorable functional outcome. Subgroup analyses based on these definitions showed that spot sign identified using the second definition were more likely to be associated with hematoma expansion (OR 18.31, 95% CI 9.11-36.8) and unfavorable functional outcomes (OR 8.78, 95% CI 3.24-23.79), while those identified using the third definition were associated with increased risk of mortality (OR 6.88, 95% CI 1.43-33.13).Clinical studies identify spot sign using different CT protocols and criteria. These differences affect the ability of spot sign to predict hematoma expansion and clinical outcomes in ICH patients.

An East Coast Perspective on Artificial Intelligence and Machine Learning: Part 1: Hemorrhagic Stroke Imaging and Triage

Hemorrhagic stroke is a medical emergency. Artificial intelligence techniques and algorithms may be used to automatically detect and quantitate intracranial hemorrhage in a semiautomated fashion. This article reviews the use of deep learning convolutional neural networks for managing hemorrhagic stroke. Such a capability may be used to alert appropriate care teams, make decisions about patient transport from a primary care center to a comprehensive stroke center, and assist in treatment selection. This article reviews artificial intelligence algorithms for intracranial hemorrhage detection, quantification, and prognostication. Multiple algorithms currently being explored are described and illustrated with the help of examples.

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.

Noncontrast computer tomography-based radiomics model for predicting intracerebral hemorrhage expansion: preliminary findings and comparison with conventional radiological model

OBJECTIVES

To develop a radiomics model for predicting hematoma expansion in patients with intracerebral hemorrhage (ICH) and to compare its predictive performance with a conventional radiological feature-based model.

METHODS

We retrospectively analyzed 251 consecutive patients with acute ICH. Two radiologists independently assessed baseline noncontrast computed tomography (NCCT) images. For each radiologist, a radiological model was constructed from radiological variables; a radiomics score model was constructed from high-dimensional quantitative features extracted from NCCT images; and a combined model was constructed using both radiological variables and radiomics score. Development of models was constructed in a primary cohort (n = 177). We then validated the results in an independent validation cohort (n = 74). The primary outcome was hematoma expansion. We compared the three models for predicting hematoma expansion. Predictive performance was assessed with the receiver operating characteristic (ROC) curve analysis.

RESULTS

In the primary cohort, combined model and radiomics model showed greater AUCs than radiological model for both readers (all p < .05). In the validation cohort, combined model and radiomics model showed greater AUCs, sensitivities, and accuracies than radiological model for reader 2 (all p < .05). Combined model showed greater AUC than radiomics model for reader 1 only in the primary cohort (p = .03). Performance of three models was comparable between reader 1 and reader 2 in both cohorts (all p > .05).

CONCLUSIONS

NCCT-based radiomics model showed high predictive performance and outperformed radiological model in the prediction of early hematoma expansion in ICH patients.

KEY POINTS

• Radiomics model showed better performance for prediction of hematoma expansion in patients with intracerebral hemorrhage than radiological feature-based model. • Hematomas which expanded in follow-up NCCT tended to be larger in baseline volume, more irregular in shape, more heterogeneous in composition, and coarser in texture. • A radiomics model provides a convenient and objective tool for prediction of hematoma expansion that helps to define subsets of patients who would benefit from anti-expansion therapy.

Meta-Analysis of Accuracy of the Spot Sign for Predicting Hematoma Growth and Clinical Outcomes

Background and Purpose- The computed tomography angiographic spot sign refers to contrast leakage within intracerebral hemorrhage (ICH). It has been proposed as a surrogate radiological marker for ICH growth. We conducted a meta-analysis to study the accuracy of the spot sign for predicting ICH growth and mortality. Methods- PubMed, Medline, conference proceedings, and article references in English up to June 2017 were searched for studies reporting "computed tomography angiography" and "spot sign" or "intracerebral hemorrhage" and "spot sign." Each study was ranked on 27 criteria resulting in a quality rating score. Bivariate random effect meta-analysis was used to calculate positive and negative likelihood ratios and area under summary receiver operating characteristics curve for ICH growth and mortality. Hematoma growth was defined using the change in ≥6 mL or ≥33% increase in volume. Results- There were 26 studies describing 5085 patients, including 15 studies not used in previous meta-analyses. Positive likelihood ratio and negative likelihood ratio for ICH growth were 4.85 (95% CI, 3.85-6.02; I²=76.1%) and 0.49 (95% CI, 0.40-0.58) and mortality were 4.65 (95% CI, 3.67-5.90) and 0.55 (95% CI, 0.40-0.69), respectively. For ICH growth, the pooled sensitivity was 0.57 (95% CI, 0.49-0.64) and pooled false positive rate was 0.12 (95% CI, 0.09-0.14). The post-test probability of ICH growth was 0.57. The area under the curve for ICH growth and mortality was 0.86 and 0.87 (CIs are not provided in bivariate method). Meta-regression showed sensitivity of the test to decline significantly with subsequent year of publication (β=-0.148; 95% CI, -0.295 to -0.001; P=0.05). Higher quality assessment is associated with lower false positive rate (β=-0.074; 95% CI, -0.126 to -0.022; P=0.006). Conclusions- The high area under the curve potentially suggests that the spot sign can predict hematoma growth and mortality. Caution is recommended in its application given the heterogeneity across studies, which is appropriate given the data.

Fluid-Blood Level and Hematoma Expansion in a Cerebral Amyloid Angiopathy-Associated Intracerebral Hematoma

Patient: Male, 77

Final Diagnosis: Cerebral amyloid angiopathy

Symptoms: Aphasia • hemiparesis

Medication: —

Clinical Procedure: Hematoma evacuation

Specialty: Neurosurgery

External ventricular drainage combined with continuous lumbar drainage in the treatment of ventricular hemorrhage

Objective: Intraventricular hemorrhage (IVH) is characterized by acute onset, rapid progression, and high disability and mortality rates. In this study, we investigated the clinical effect of external ventricular drainage combined with continuous lumbar drainage in IVH treatments.

Methods: 114 patients with IVH treated at the Department of Neurosurgery, First Affiliated Hospital of Wannan Medical College from January 2015 to December 2017, were included in the study. Based on the different surgical methods, patients were divided into control (n=79) and study groups (n=35). The control group was treated with external ventricular drainage, whereas the study group was treated with external ventricular drainage combined with continuous lumbar drainage. The incidence of intracranial infection and hydrocephalus was compared between the two groups. The Glasgow coma scale (GCS) and the Glasgow outcome scale (GOS) were compared between the two groups 7 days postoperatively and at follow-up visits, respectively.

Results: The incidence of intracranial infection and hydrocephalus in the study group was significantly lower compared with those in the control group (P<0.05). Seven days postoperatively, the GCS score of the study group was significantly higher than that of the control group (P<0.05). At the 3-month follow-up visit, the GOS score of the study group was higher than that of the control group (P<0.05).

Conclusions: Using external ventricular drainage combined with continuous lumbar drainage can reduce the incidence of intracranial infection and hydrocephalus and improve the prognoses and quality of life in patients with IVH.

Spot and Diffuse Signs: Quantitative Markers of Intracranial Hematoma Expansion at Dual-Energy CT

Purpose To compare dual-energy CT with iodine quantification to single-energy CT for evaluation of the spot sign for intracranial hematoma expansion. Materials and Methods In this retrospective study, 42 patients (mean age, 66 years ± 15 [standard deviation]; 19 women) were referred for dual-energy CT assessment of intracranial hemorrhage from October 2014 to January 2017. A machine learning approach (naive Bayes classifier) was used to identify iodine markers of extravasation for risk of hematoma expansion. Specificity and sensitivity of these markers were then independently validated in 65 new patients from February 2017 to February 2018. Results Analysis of dual-energy CT images identified two features of iodine extravasation: total iodine concentration within the hematoma (I_h) and focal iodine concentration in the brightest spot in the hematoma (I_bs) as predictors of expansion. The I2 score derived from these features provided a measure of expansion probability. Optimal classification threshold was an I2 score of 20 (95% confidence interval [CI]: 18, 23), leading to correct identification of 39 of 46 (85%; 95% CI: 71%, 94%) of the hematomas on the training set (sensitivity of 79% [11 of 14; 95% CI: 57%, 100%] and specificity of 88% [28 of 32; 95% CI: 76%, 99%]), and 62 of 70 (89%; 95% CI: 79%, 95%) of the hematomas on the validation set (sensitivity of 71% [10 of 14; 95% CI: 48%, 95%] and specificity of 93% [52 of 56; 95% CI: 86%, 100%]). Sensitivity, specificity, and accuracy of conventional spot sign were, respectively, 57% (eight of 14), 90% (29 of 32), and 80% (37 of 46) on the training set and 57% (eight of 14), 83% (47 of 56), and 75% (53 of 70) on the validation set. Conclusion This study identified two quantitative markers of intracranial hemorrhage expansion at dual-energy CT of the brain. The I2 score derived from these markers highlights the utility of dual-energy CT measurements of iodine content for high sensitivity risk assessment. © RSNA, 2018 Online supplemental material is available for this article.

Accuracy of spot sign in predicting hematoma expansion and clinical outcome: A meta-analysis

BACKGROUND

Spot sign on computed tomography angiography (CTA) has been reported as a risk factor for hematoma expansion (HE) and poor outcome after intracerebral hemorrhage (ICH). We performed a meta-analysis to investigate the predictive accuracy of spot sign for HE, mortality risk, and poor outcome.

METHODS

We searched PubMed, Embase, and the Cochrane Library for relevant studies. Studies were incorporated if they reported data on relationship between CTA spot sign and HE, mortality or poor outcome.

RESULTS

Twenty-nine studies were pooled in this meta-analysis. The spot sign occurred in 23.4% patients with spontaneous ICH undergoing CTA scans. It showed a sensitivity of 62% (95% confidence interval [CI] 54-69), with a specificity of 88% (95% CI 85-91). Spot sign was related with increased risk of HE (odds ratios [OR] 8.49, 95% CI 7.28-9.90). In the analysis of association between spot sign and outcome, patients with spot sign had a significant higher risk of in-hospital death (OR 5.08, 95% CI 3.16-8.18) and 3-month death (OR 3.80, 95% CI 2.62-5.52). The spot sign was also a predictor of poor outcome at discharge (OR 6.40, 95% CI 3.41-12.03) and at 3 months (OR 4.44, 95% CI 2.33-8.46).

CONCLUSIONS

The overall incidence of CTA spot sign in spontaneous ICH patients is substantial. Spot sign demonstrated a good diagnostic performance in predicting HE and was closely associated with increased risk of death and poor outcome.

Prevention of haematoma progression by tranexamic acid in intracerebral haemorrhage patients with and without spot sign on admission scan: a statistical analysis plan of a pre-specified sub-study of the TICH-2 trial

OBJECTIVE

We present the statistical analysis plan of a prespecified Tranexamic Acid for Hyperacute Primary Intracerebral Haemorrhage (TICH)-2 sub-study aiming to investigate, if tranexamic acid has a different effect in intracerebral haemorrhage patients with the spot sign on admission compared to spot sign negative patients. The TICH-2 trial recruited above 2000 participants with intracerebral haemorrhage arriving in hospital within 8 h after symptom onset. They were included irrespective of radiological signs of on-going haematoma expansion. Participants were randomised to tranexamic acid versus matching placebo. In this subgroup analysis, we will include all participants in TICH-2 with a computed tomography angiography on admission allowing adjudication of the participants' spot sign status.

RESULTS

Primary outcome will be the ability of tranexamic acid to limit absolute haematoma volume on computed tomography at 24 h (± 12 h) after randomisation among spot sign positive and spot sign negative participants, respectively. Within all outcome measures, the effect of tranexamic acid in spot sign positive/negative participants will be compared using tests of interaction. This sub-study will investigate the important clinical hypothesis that spot sign positive patients might benefit more from administration of tranexamic acid compared to spot sign negative patients. Trial registration ISRCTN93732214 ( http://www.isrctn.com ).

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.

Heterogeneity Signs on Noncontrast Computed Tomography Predict Hematoma Expansion after Intracerebral Hemorrhage: A Meta-Analysis

Background and Purpose

Hematoma expansion (HE) is related to clinical deterioration after intracerebral hemorrhage (ICH) and noncontrast computed tomography (NCCT) signs are indicated as predictors for HE but with inconsistent conclusions. We aim to clarify the correlations of NCCT heterogeneity signs with HE by meta-analysis of related studies.

Methods

PubMed, Embase, and Cochrane library were searched for eligible studies exploring the relationships between NCCT heterogeneity signs (hypodensity, mixed density, swirl sign, blend sign, and black hole sign) and HE. Poor outcome and mortality were considered as secondary outcomes. Odds ratio (OR) and its 95% confidence intervals (CIs) were selected as the effect size and combined using random effects model.

Results

Fourteen studies were included, involving 3240 participants and 435 HEs. The summary results suggested statistically significant correlations of heterogeneity signs with HE (OR, 5.17; 95% CI, 3.72–7.19, P < 0.001), poor outcome (OR, 3.60; 95% CI, 1.98–6.54, P < 0.001), and mortality (OR, 4.64; 95%, 2.96–7.27, P < 0.001).

Conclusions

Our findings suggested that hematoma heterogeneity signs on NCCT were positively associated with the increased risk of HE, poor outcome, and mortality rate in ICH.

Comparison of Spot Sign, Blend Sign and Black Hole Sign for Outcome Prediction in Patients with Intracerebral Hemorrhage

Background and Purpose

Blend sign (BS) and black hole sign (BHS) on non-contrast computed tomography (NCCT) and spot sign (SS) on CT-angiography (CTA) are indicators of early hematoma expansion in spontaneous intracerebral hemorrhage (ICH). However, their independent contributions to outcome have not been well explored.

Methods

In this retrospective study, inclusion criteria were: 1) spontaneous ICH and 2) NCCT and CTA performed on admission within 6 hours after onset of symptoms. Discharge outcome was dichotomized as good (modified Rankin Scale [mRS] 0-3) and poor (mRS 4-6) outcomes. The impacts of BHS, BS and SS on outcome were assessed in univariate and multivariable logistic regression models.

Results

Of 182 patients with spontaneous ICH, 26 (14.3%) presented with BHS, 37 (20.3%) with BS and 39 (21.4%) with SS. There was a substantial correlation between SS and BS (κ=0.701) and a moderate correlation between SS and BHS (κ=0.424). In univariable logistic regression, higher baseline hematoma volume (P<0.001), intraventricular hemorrhage (P=0.002) and the presence of BHS/BS/SS (all P<0.001) on admission CT scan were associated with poor outcome. Multivariable analysis identified intraventricular haemorrhage (odds ratio [OR] 2.22 per mL, P=0.022), baseline hematoma volume (OR 1.03 per mL, P<0.001) and SS on CTA (OR 11.43, P<0.001) as independent predictors of poor outcome, showing that SS compared to BS and BHS was more powerful to predict poor outcome.

Conclusions

The NCCT BHS and BS are correlated with the CTA SS and are reliable predictors of poor outcome in patients with ICH. Of the CT variables indicating early hematoma expansion, SS on CTA was the most reliable outcome predictor. However, given their correlation with SS on CTA, BS and BHS on NCCT can be useful for predicting outcome if CTA is not obtainable.

Intensive Blood Pressure Reduction and Spot Sign in Intracerebral Hemorrhage: A Secondary Analysis of a Randomized Clinical Trial

Importance

The computed tomographic angiography (CTA) spot sign is associated with intracerebral hemorrhage (ICH) expansion and may mark those patients most likely to benefit from intensive blood pressure (BP) reduction.

Objective

To investigate whether the spot sign is associated with ICH expansion across a wide range of centers and whether intensive BP reduction decreases hematoma expansion and improves outcome in patients with ICH and a spot sign.

Design, Setting, and Participants

SCORE-IT (Spot Sign Score in Restricting ICH Growth) is a preplanned prospective observational study nested in the Antihypertensive Treatment of Acute Cerebral Hemorrhage II (ATACH-II) randomized clinical trial. Participants included consecutive patients with primary ICH who underwent a CTA within 8 hours from onset at 59 sites from May 15, 2011, through December 19, 2015. Data were analyzed for the present study from July 1 to August 31, 2016.

Main Outcomes and Measures

Patients in ATACH-II were randomized to intensive (systolic BP target, <140 mm Hg) vs standard (systolic BP target, <180 mm Hg) BP reduction within 4.5 hours from onset. Expansion of ICH was defined as hematoma growth of greater than 33%, and an unfavorable outcome was defined as a 90-day modified Rankin Scale score of 4 or greater (range, 0-6). The association among BP reduction, ICH expansion, and outcome was investigated with multivariable logistic regression.

Results

A total of 133 patients (83 men [62.4%] and 50 women [37.6%]; mean [SD] age, 61.9 [13.1] years) were included. Of these, 53 (39.8%) had a spot sign, and 24 of 123 without missing data (19.5%) experienced ICH expansion. The spot sign was associated with expansion with sensitivity of 0.54 (95% CI, 0.34-0.74) and specificity of 0.63 (95% CI, 0.53-0.72). After adjustment for potential confounders, intensive BP treatment was not associated with a significant reduction of ICH expansion (relative risk, 0.83; 95% CI, 0.27-2.51; P = .74) or improved outcome (relative risk of 90-day modified Rankin Scale score ≥4, 1.24; 95% CI, 0.53-2.91; P = .62) in spot sign-positive patients.

Conclusions and Relevance

The predictive performance of the spot sign for ICH expansion was lower than in prior reports from single-center studies. No evidence suggested that patients with ICH and a spot sign specifically benefit from intensive BP reduction.

Trial Registration

clinicaltrials.gov Identifier: NCT01176565.

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.

Phantom-based standardization of CT angiography images for spot sign detection

PURPOSE

The CT angiography (CTA) spot sign is a strong predictor of hematoma expansion in intracerebral hemorrhage (ICH). However, CTA parameters vary widely across centers and may negatively impact spot sign accuracy in predicting ICH expansion. We developed a CT iodine calibration phantom that was scanned at different institutions in a large multicenter ICH clinical trial to determine the effect of image standardization on spot sign detection and performance.

METHODS

A custom phantom containing known concentrations of iodine was designed and scanned using the stroke CT protocol at each institution. Custom software was developed to read the CT volume datasets and calculate the Hounsfield unit as a function of iodine concentration for each phantom scan. CTA images obtained within 8 h from symptom onset were analyzed by two trained readers comparing the calibrated vs. uncalibrated density cutoffs for spot sign identification. ICH expansion was defined as hematoma volume growth >33%.

RESULTS

A total of 90 subjects qualified for the study, of whom 17/83 (20.5%) experienced ICH expansion. The number of spot sign positive scans was higher in the calibrated analysis (67.8 vs 38.9% p < 0.001). All spot signs identified in the non-calibrated analysis remained positive after calibration. Calibrated CTA images had higher sensitivity for ICH expansion (76 vs 52%) but inferior specificity (35 vs 63%) compared with uncalibrated images.

CONCLUSION

Normalization of CTA images using phantom data is a feasible strategy to obtain consistent image quantification for spot sign analysis across different sites and may improve sensitivity for identification of ICH expansion.

Computed tomography angiography spot sign predicts intraprocedural aneurysm rupture in subarachnoid hemorrhage

INTRODUCTION

To analyze whether the computed tomography angiography (CTA) spot sign predicts the intraprocedural rupture rate and outcome in patients with aneurysmal subarachnoid hemorrhage (aSAH).

METHODS

From a prospective nationwide multicenter registry database, 1023 patients with aneurysmal subarachnoid hemorrhage (aSAH) were analyzed retrospectively. Descriptive statistics and logistic regression analysis were used to compare spot sign-positive and -negative patients with aneurysmal intracerebral hemorrhage (aICH) for baseline characteristics, aneurysmal and ICH imaging characteristics, treatment and admission status as well as outcome at discharge and 1-year follow-up (1YFU) using the modified Rankin Scale (mRS).

RESULTS

A total of 218 out of 1023 aSAH patients (21%) presented with aICH including 23/218 (11%) patients with spot sign. Baseline characteristics were comparable between spot sign-positive and -negative patients. There was a higher clip-to-coil ratio in patients with than without aICH (both spot sign positive and negative). Median aICH volume was significantly higher in the spot sign-positive group (50 ml, 13-223 ml) than in the spot sign-negative group (18 ml, 1-416; p < 0.0001). Patients with a spot sign-positive aICH thus were three times as likely as those with spot sign-negative aICH to show an intraoperative aneurysm rupture [odds ratio (OR) 3.04, 95% confidence interval (CI) 1.04-8.92, p = 0.046]. Spot sign-positive aICH patients showed a significantly worse mRS at discharge (p = 0.039) than patients with spot sign-negative aICH (median mRS 5 vs. 4). Logistic regression analysis showed that the spot sign was an aICH volume-dependent predictor for outcome. Both spot sign-positive and -negative aICH patients showed comparable rates of hospital death, death at 1YFU and mRS at 1YFU.

CONCLUSION

In this multicenter data analysis, patients with spot sign-positive aICH showed higher aICH volumes and a higher rate of intraprocedural aneurysm rupture, but comparable long-term outcome to spot sign-negative aICH patients.

Computed Tomographic Blend Sign Is Associated With Computed Tomographic Angiography Spot Sign and Predicts Secondary Neurological Deterioration After Intracerebral Hemorrhage

BACKGROUND AND PURPOSE

Significant early hematoma growth in patients with intracerebral hemorrhage is an independent predictor of poor functional outcome. Recently, the novel blend sign (BS) has been introduced as a new imaging sign for predicting hematoma growth in noncontrast computed tomography. Another parameter predicting increasing hematoma size is the well-established spot sign (SS) visible in computed tomographic angiography. We, therefore, aimed to clarify the association between established SS and novel BS and their values predicting a secondary neurological deterioration.

METHODS

Retrospective study inclusion criteria were (1) spontaneous intracerebral hemorrhage confirmed on noncontrast computed tomography and (2) noncontrast computed tomography and computed tomographic angiography performed on admission within 6 hours after onset of symptoms. We defined a binary outcome (secondary neurological deterioration versus no secondary deterioration). As secondary neurological deterioration, we defined (1) early hemicraniectomy under standardized criteria or (2) secondary decrease of Glasgow Coma Scale of >3 points, both within the first 48 hours after symptom onset.

RESULTS

Of 182 patients with spontaneous intracerebral hemorrhage, 37 (20.3%) presented with BS and 39 (21.4%) with SS. Of the 81 patients with secondary deterioration, 31 (38.3%) had BS and SS on admission. Multivariable logistic regression analysis identified hematoma volume (odds ratio, 1.07 per mL; P≤0.001), intraventricular hemorrhage (odds ratio, 3.08; P=0.008), and the presence of BS (odds ratio, 11.47; P≤0.001) as independent predictors of neurological deterioration.

CONCLUSIONS

The BS, which is obtainable in noncontrast computed tomography, shows a high correlation with the computed tomographic angiography SS and is a reliable predictor of secondary neurological deterioration after spontaneous intracerebral hemorrhage.

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.

Hemorrhage or Ischemia? The Importance of 'Spotting' it Right

BACKGROUND

A 78-year-old woman was transferred directly to an ICU because of intracerebral hemorrhage. However, on careful review of the initial imaging, the likely diagnosis was ischemic stroke and reperfusion hemorrhage.

METHODS

Case report was explained.

RESULTS

The patient suffered significant reperfusion hemorrhage. A CT angiogram revealed contrast extravasation "spot sign" in the bed of the expanding hemorrhage and an occlusive thromboembolism distal to the initial ischemic insult.

CONCLUSION

In this case of embolic ischemic stroke with reperfusion hemorrhage, contrast extravasation "spot sign" was associated with hematoma expansion.

Prediction of Intracerebral Haemorrhage Expansion with Clinical, Laboratory, Pharmacologic, and Noncontrast Radiographic Variables

Background

Hematoma expansion confers excess mortality in intracerebral haemorrhage, and is potentially preventable if at-risk patients can be identified. Contrast extravasation on initial computed tomographic angiography strongly predicts hematoma expansion but is not very sensitive, and most centers have not yet integrated computed tomographic angiography into acute intracerebral haemorrhage management. We therefore asked whether other presentation variables can predict hematoma expansion.

Methods

We searched the electronic medical records of a large integrated healthcare delivery system to identify patients with a hospitalization discharge diagnosis of intracerebral haemorrhage between the years 2008 and 2010. Hematoma expansion was defined as radiographic increase by 1/3 or by 12·5 ml within 48 h of presentation. Pre-specified patient demographic and clinical presentation variables were extracted. Stepwise multivariable logistic regression was performed to model hematoma expansion. Because some patients may have died from hematoma expansion without a second head computed tomography, we constructed a separate model including patients that died without a second head computed tomography in 48 h, hematoma expansion or death.

Results

Ninety-one of 257 patients (35%) had hematoma expansion. Antithrombotic use (odds ratio = 1·9, P = 0·04) and initial mNIHSS (modified National Institutes of Health Stroke Scale; odds ratio = 1·06, P = 0·001) were significant predictors in the hematoma expansion model (area under the Receiver–Operator Characteristics curve, AUROC = 0·6712, pseudo- r2 = 0·0641). 163 of 343 patients (48%) had hematoma expansion or death. Age (odds ratio = 1·02, P = 0·02), initial mNIHSS (odds ratio = 1·07, P < 0·001), and initial hematoma volume (odds ratio = 1·01, P = 0·03) were significant predictors of hematoma expansion or death (AUROC = 0·7579, pseudo- r2 = 0·1722).

Conclusion

Clinical and noncontrast radiographic variables only weakly predict hematoma expansion. Examination of other indicators, such as computed tomographic angiography contrast extravasation (the ‘spot sign’), may prove more valuable in acute intracerebral haemorrhage care.

Dual-Energy CT: What the Neuroradiologist Should Know

Because of the different attenuations of tissues at different energy levels, dual-energy CT offers tissue differentiation and characterization, reduction of artifacts, and remodeling of contrast-to-noise ratio (CNR) and signal-to-noise ratio (SNR), hereby creating new opportunities and insights in CT imaging. The applications for dual-energy imaging in neuroradiology are various and still expanding. Automated bone removal is used in CT angiography and CT venography of the intracranial vessels. Monoenergetic reconstructions can be used in patients with or without metal implants in the brain and spine to reduce artifacts, improve CNR and SNR, or to improve iodine conspicuity. Differentiation of iodine and hemorrhage is used in high-density lesions, after intra-arterial recanalization in stroke patients or after administration of contrast media. Detection of underlying (vascular and non-vascular) pathology and spot sign can be used in patients presenting with (acute) intracranial hemorrhage.

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.

Imaging of acute stroke prior to treatment: current practice and evolving techniques

Standard imaging in acute stroke is undertaken with the aim of diagnosing the underlying cause and excluding stroke mimics. In the presence of ischaemic stroke, imaging is also needed to assess patient suitability for treatment with intravenous thrombolysis. Non-contrast CT is predominantly used, but MRI can also exclude any contraindications to thrombolysis treatment. Advanced stroke imaging such as CT and MR angiography and perfusion imaging are increasingly used in an acute setting. In this review, we discuss the evidence for the application of these advanced techniques in the imaging of acute stroke.