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Robbe MMQ, Pinckaers FME, Olthuis SGH, Bos MJ, van Oostenbrugge RJ, van Zwam WH, Staals J, Postma AA. Procedural Blood Pressure and Intracranial Hemorrhage on Dual-Energy Computed Tomography After Endovascular Stroke Treatment. Cardiovasc Intervent Radiol 2024; 47:483-491. [PMID: 38062172 DOI: 10.1007/s00270-023-03619-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Accepted: 11/06/2023] [Indexed: 04/07/2024]
Abstract
PURPOSE Optimal systolic blood pressure (SBP) management during endovascular treatment (EVT) for acute ischemic stroke remains a topic of debate. Though BP is associated with worse functional outcome, the relationship between BP and post-procedural intracranial hemorrhage (ICH) is less well-known. We aimed to investigate the association between BP during EVT and post-procedural ICH on dual-energy CT (DECT). METHODS We included all patients who underwent EVT for an anterior circulation large vessel occlusion between 2010 and 2019, and received DECT < 3 h post-EVT. All BP measurements during the EVT procedure were used to calculate mean arterial pressure (MAPmean), mean SBP (SBPmean), and SBPmax-min (highest minus lowest). ICH was assessed using virtual post-procedural unenhanced DECT reconstructions and classified as intraparenchymal or extraparenchymal. Symptomatic ICH was scored according to the Heidelberg criteria. The association between different BP parameters and ICH was assessed using multivariable logistic regression. RESULTS We included 478 patients. Seventy-six patients (16%) demonstrated ICH on DECT, of which 26 (34%) were intraparenchymal. Symptomatic intraparenchymal and extraparenchymal ICH occurred in 10 (38%) and 4 (8%) patients. SBPmax, SBPmean, and MAPmean were associated with intraparenchymal ICH with an adjusted odds ratio of 1.19 (95%CI, 1.02-1.39), 1.22 (95%CI, 1.03-1.46), and 1.40 (95%CI, 1.09-1.81) per 10 mmHg, while BP was not significantly associated with extraparenchymal ICH. BP did not differ between asymptomatic and symptomatic ICH. CONCLUSION Procedural BP is associated with intraparenchymal ICH on post-EVT DECT but not with extraparenchymal ICH. Future studies should evaluate whether individual procedural BP management reduces post-EVT ICH and improves clinical outcome.
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Affiliation(s)
- M M Q Robbe
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, P. Debeyelaan 25, 6229HX, Maastricht, The Netherlands.
- School for Cardiovascular Diseases (CARIM), Maastricht University, Maastricht, The Netherlands.
| | - F M E Pinckaers
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, P. Debeyelaan 25, 6229HX, Maastricht, The Netherlands
- School for Cardiovascular Diseases (CARIM), Maastricht University, Maastricht, The Netherlands
| | - S G H Olthuis
- School for Cardiovascular Diseases (CARIM), Maastricht University, Maastricht, The Netherlands
- Department of Neurology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - M J Bos
- Departments of Anesthesiology and Pain Medicine, Maastricht University Medical Center, Maastricht, The Netherlands
| | - R J van Oostenbrugge
- School for Cardiovascular Diseases (CARIM), Maastricht University, Maastricht, The Netherlands
- Department of Neurology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - W H van Zwam
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, P. Debeyelaan 25, 6229HX, Maastricht, The Netherlands
- School for Cardiovascular Diseases (CARIM), Maastricht University, Maastricht, The Netherlands
| | - J Staals
- School for Cardiovascular Diseases (CARIM), Maastricht University, Maastricht, The Netherlands
- Department of Neurology, Maastricht University Medical Center, Maastricht, The Netherlands
| | - A A Postma
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Center, P. Debeyelaan 25, 6229HX, Maastricht, The Netherlands
- School for Mental Health and Sciences (MHENS), Maastricht University, Maastricht, The Netherlands
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Pham J, Ng FC. Novel advanced imaging techniques for cerebral oedema. Front Neurol 2024; 15:1321424. [PMID: 38356883 PMCID: PMC10865379 DOI: 10.3389/fneur.2024.1321424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2023] [Accepted: 01/09/2024] [Indexed: 02/16/2024] Open
Abstract
Cerebral oedema following acute ischemic infarction has been correlated with poor functional outcomes and is the driving mechanism of malignant infarction. Measurements of midline shift and qualitative assessment for herniation are currently the main CT indicators for cerebral oedema but have limited sensitivity for small cortical infarcts and are typically a delayed sign. In contrast, diffusion-weighted (DWI) or T2-weighted magnetic resonance imaging (MRI) are highly sensitive but are significantly less accessible. Due to the need for early quantification of cerebral oedema, several novel imaging biomarkers have been proposed. Based on neuroanatomical shift secondary to space-occupying oedema, measures such as relative hemispheric volume and cerebrospinal fluid displacement are correlated with poor outcomes. In contrast, other imaging biometrics, such as net water uptake, T2 relaxometry and blood brain barrier permeability, reflect intrinsic tissue changes from the influx of fluid into the ischemic region. This review aims to discuss quantification of cerebral oedema using current and developing advanced imaging techniques, and their role in predicting clinical outcomes.
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Affiliation(s)
- Jenny Pham
- Department of Radiology, Royal Melbourne Hospital, Parkville, VIC, Australia
| | - Felix C. Ng
- Department of Neurology, Royal Melbourne Hospital, Parkville, VIC, Australia
- Department of Neurology, Austin Health, Heidelberg, VIC, Australia
- Department of Medicine at Royal Melbourne Hospital, Melbourne Brain Centre, University of Melbourne, Parkville, VIC, Australia
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Ebaid NY, Mouffokes A, Yasen NS, Elrosasy AM, Philip KG, Assy MM, Alsowey AM. Diagnostic accuracy of dual-energy computed tomography in the diagnosis of neurological complications after endovascular treatment of acute ischaemic stroke: a systematic review and meta-analysis. Br J Radiol 2024; 97:73-92. [PMID: 38263833 PMCID: PMC11027317 DOI: 10.1093/bjr/tqad007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2023] [Revised: 09/28/2023] [Accepted: 10/22/2023] [Indexed: 01/25/2024] Open
Abstract
OBJECTIVES To investigate dual-energy computed tomography's (DECT) diagnostic performance in detecting neurological complications following endovascular therapy (EVT) of acute ischaemic stroke (AIS). METHODS We performed the literature search using Web of Science, Scopus, PubMed, EBSCO, and Science Direct databases for published related studies. The selected studies estimated the validity of DECT in the detection of neurological complications after EVT for AIS. Study quality assessment was performed utilizing the Quality of Diagnostic Accuracy Studies-2 Tool. Our meta-analysis calculated the pooled sensitivity, negative likelihood ratio, specificity, and positive likelihood ratio for each detected complication. The summary receiver operating characteristics (sROC) curve was utilized to estimate the area under the curve (AUC). RESULTS Of 22 studies, 21 were included in the quantitative synthesis. In the detection of intracerebral haemorrhage (ICH), DECT pooled overall sensitivity and specificity were 69.9% (95% CI, 44.5%-86.8%) and 100% (95% CI, 92.1%-100%); whereas, in the detection of ischaemia, they were 85.9% (95% CI, 80.4%-90%) and 90.7% (95% CI, 87%-93.5%), respectively. On the sROC curve, AUC values of 0.954 and 0.952 were recorded for the detection of ICH and ischaemia, respectively. CONCLUSIONS DECT demonstrated high accuracy and specificity in the detection of neurological complications post-endovascular treatment of AIS. However, further prospective studies with a standardized reference test and a larger sample size are recommended to support these findings. ADVANCES IN KNOWLEDGE DECT is a rapid and valid imaging tool for the prediction of ICH and cerebral ischaemia after the EVT of AIS.
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Affiliation(s)
- Noha Yahia Ebaid
- Radiodiagnosis Department, Faculty of Medicine, Zagazig University, Zagazig 40511, Egypt
- Medical Research Group of Egypt, Cairo 11511, Egypt
| | - Adel Mouffokes
- Medical Research Group of Egypt, Cairo 11511, Egypt
- Faculty of Medicine, University of Oran 1 Ahmed Ben Bella, Oran 31020, Algeria
| | - Noha S Yasen
- Medical Research Group of Egypt, Cairo 11511, Egypt
- Faculty of Applied Medical Sciences, Misr University for Science and Technology, Cairo 11511, Egypt
| | - Amr M Elrosasy
- Medical Research Group of Egypt, Cairo 11511, Egypt
- Faculty of Medicine, Cairo University, Cairo 11511, Egypt
| | - Kerollos George Philip
- Medical Research Group of Egypt, Cairo 11511, Egypt
- Faculty of Medicine, Sohag University, Sohag 82511, Egypt
| | - Mostafa Mohamad Assy
- Radiodiagnosis Department, Faculty of Medicine, Zagazig University, Zagazig 40511, Egypt
| | - Ahmed Mohamed Alsowey
- Radiodiagnosis Department, Faculty of Medicine, Zagazig University, Zagazig 40511, Egypt
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4
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Pham J, Gan C, Dabboucy J, Stella DL, Dowling R, Yan B, Bush S, Williams C, Mitchell PJ, Desmond P, Thijs V, Asadi H, Brooks M, Maingard J, Jhamb A, Pavlin-Premrl D, Campbell BC, Ng FC. Occult contrast retention post-thrombectomy on 24-h follow-up dual-energy CT: Associations and impact on imaging analysis. Int J Stroke 2023; 18:1228-1237. [PMID: 37260232 DOI: 10.1177/17474930231182018] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
BACKGROUND Following reperfusion treatment in ischemic stroke, computed tomography (CT) imaging at 24 h is widely used to assess radiological outcomes. Even without visible hyperattenuation, occult angiographic contrast may persist in the brain and confound Hounsfield unit-based imaging metrics, such as net water uptake (NWU). AIMS We aimed to assess the presence and factors associated with retained contrast post-thrombectomy on 24-h imaging using dual-energy CT (DECT), and its impact on the accuracy of NWU as a measure of cerebral edema. METHODS Consecutive patients with anterior circulation large vessel occlusion who had post-thrombectomy DECT performed 24-h post-treatment from two thrombectomy stroke centers were retrospectively studied. NWU was calculated by interside comparison of HUs of the infarct lesion and its mirror homolog. Retained contrast was quantified by the difference in NWU values with and without adjustment for iodine. Patients with visible hyperdensities from hemorrhagic transformation or visible contrast retention and bilateral infarcts were excluded. Cerebral edema was measured by relative hemispheric volume (rHV) and midline shift (MLS). RESULTS Of 125 patients analyzed (median age 71 (IQR = 61-80), baseline National Institutes of Health Stroke Scale (NIHSS) 16 (IQR = 9.75-21)), reperfusion (defined as extended-Thrombolysis-In-Cerebral-Infarction 2b-3) was achieved in 113 patients (90.4%). Iodine-subtracted NWU was significantly higher than unadjusted NWU (17.1% vs 10.8%, p < 0.001). In multivariable median regression analysis, increased age (p = 0.024), number of passes (p = 0.006), final infarct volume (p = 0.023), and study site (p = 0.021) were independently associated with amount of retained contrast. Iodine-subtracted NWU correlated with rHV (rho = 0.154, p = 0.043) and MLS (rho = 0.165, p = 0.033) but unadjusted NWU did not (rHV rho = -0.035, p = 0.35; MLS rho = 0.035, p = 0.347). CONCLUSIONS Angiographic iodine contrast is retained in brain parenchyma 24-h post-thrombectomy, even without visually obvious hyperdensities on CT, and significantly affects NWU measurements. Adjustment for retained iodine using DECT is required for accurate NWU measurements post-thrombectomy. Future quantitative studies analyzing CT after thrombectomy should consider occult contrast retention.
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Affiliation(s)
- Jenny Pham
- Department of Neurology, The Royal Melbourne Hospital, Parkville, VIC, Australia
| | - Calvin Gan
- Department of Radiology, The Royal Melbourne Hospital, Parkville, VIC, Australia
| | - Jasmin Dabboucy
- Department of Neurology, Austin Health, Heidelberg, VIC, Australia
| | - Damien L Stella
- Department of Radiology, The Royal Melbourne Hospital, Parkville, VIC, Australia
| | - Richard Dowling
- Department of Radiology, The Royal Melbourne Hospital, Parkville, VIC, Australia
| | - Bernard Yan
- Department of Radiology, The Royal Melbourne Hospital, Parkville, VIC, Australia
- Department of Radiology, Austin Health, Heidelberg, VIC, Australia
| | - Steven Bush
- Department of Radiology, The Royal Melbourne Hospital, Parkville, VIC, Australia
| | - Cameron Williams
- Department of Radiology, The Royal Melbourne Hospital, Parkville, VIC, Australia
| | - Peter J Mitchell
- Department of Radiology, The Royal Melbourne Hospital, Parkville, VIC, Australia
| | - Patricia Desmond
- Department of Radiology, The Royal Melbourne Hospital, Parkville, VIC, Australia
- The University of Melbourne, Parkville, VIC, Australia
| | - Vincent Thijs
- Department of Neurology, Austin Health, Heidelberg, VIC, Australia
- Division of Stroke, Florey Institute of Neuroscience and Mental Health, Heidelberg, VIC, Australia
| | - Hamed Asadi
- Department of Radiology, Austin Health, Heidelberg, VIC, Australia
| | - Mark Brooks
- Department of Radiology, Austin Health, Heidelberg, VIC, Australia
| | - Julian Maingard
- Department of Radiology, Austin Health, Heidelberg, VIC, Australia
| | - Ash Jhamb
- Department of Radiology, Austin Health, Heidelberg, VIC, Australia
| | - Davor Pavlin-Premrl
- Department of Radiology, Austin Health, Heidelberg, VIC, Australia
- Melbourne Brain Centre, Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, Parkville, VIC, Australia
| | - Bruce Cv Campbell
- Department of Neurology, The Royal Melbourne Hospital, Parkville, VIC, Australia
- Melbourne Brain Centre, Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, Parkville, VIC, Australia
| | - Felix C Ng
- Department of Neurology, The Royal Melbourne Hospital, Parkville, VIC, Australia
- Department of Neurology, Austin Health, Heidelberg, VIC, Australia
- Melbourne Brain Centre, Department of Medicine, Royal Melbourne Hospital, The University of Melbourne, Parkville, VIC, Australia
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5
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Wang T, Ding W, Chen Q, Ding Z. Hemorrhagic Transformation Assessment Based on Dual Energy CT of Immediately and Twenty-Four Hours after Endovascular Thrombectomy for Acute Ischemic Stroke. Diagnostics (Basel) 2023; 13:2493. [PMID: 37568856 PMCID: PMC10416895 DOI: 10.3390/diagnostics13152493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Revised: 07/24/2023] [Accepted: 07/25/2023] [Indexed: 08/13/2023] Open
Abstract
BACKGROUND Dual-energy CT (DECT) shows good performance in differentiating hemorrhage from contrast staining (CS). However, no guidelines have standardized the post-endovascular thrombectomy (EVT) examination time. We evaluated the value of performing DECT immediately and 24 h post-EVT in the diagnosis and prediction of hemorrhagic transformation (HT). METHODS Two readers evaluated simulated conventional CT (sCCT) images compared with a second reading with DECT, establishing the diagnosis of HT immediately and 24 h post-EVT. Another reader's diagnosis 2-7 days post-EVT using non-contrast CT was identified as the final diagnostic criteria. RESULTS DECT performed immediately and 24 h post-EVT changed 22.4% (52/232) and 12.5% (29/232) of sCCT-based HT diagnoses, respectively (χ2 = 10.7, p < 0.05). The sensitivity, negative predictive value (NPV), and accuracy of DECT performed immediately post-EVT for predicting the final diagnosis of HT were 33.6%, 58.9%, and 65.9%, respectively, whereas those for DECT performed 24 h post-EVT were 82.4%, 84.3%, and 90.9%, respectively (χ2 = 58.0, χ2 = 42.9, χ2 = 13.6; p < 0.05). The specificity and positive predictive value were both 100.0%. Delayed HT occurred in 50.0% (78/156) and 42.2% (19/45) of patients with CS diagnosed immediately and 24 h post-EVT, respectively. CONCLUSIONS DECT performed immediately post-EVT changed a greater proportion of real-time HT diagnoses, whereas that performed 24 h post-EVT had higher sensitivity, NPV, and accuracy in predicting the final diagnosis of HT. A substantial proportion of patients with CS diagnosed at these two post-EVT timepoints subsequently developed delayed HT.
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Affiliation(s)
- Tianyu Wang
- Department of Radiology, Affiliated Hangzhou First People’s Hospital, Zhejiang University School of Medicine, Hangzhou 310006, China;
| | - Weili Ding
- Graduate School of Zhejiang Chinese Medical University, Hangzhou 310053, China; (W.D.); (Q.C.)
| | - Qing Chen
- Graduate School of Zhejiang Chinese Medical University, Hangzhou 310053, China; (W.D.); (Q.C.)
| | - Zhongxiang Ding
- Department of Radiology, Affiliated Hangzhou First People’s Hospital, Zhejiang University School of Medicine, Hangzhou 310006, China;
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Pinckaers FME, Mentink MMG, Boogaarts HD, van Zwam WH, van Oostenbrugge RJ, Postma AA. Early post-endovascular treatment contrast extravasation on dual-energy CT is associated with clinical and radiological stroke outcomes: A 10-year single-centre experience. Eur Stroke J 2023; 8:508-516. [PMID: 37231689 PMCID: PMC10334176 DOI: 10.1177/23969873231157901] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 01/31/2023] [Indexed: 11/22/2023] Open
Abstract
OBJECTIVE To determine the association between early post-endovascular treatment (EVT) contrast extravasation (CE) on dual-energy CT (DECT) and stroke outcomes. METHODS EVT records in 2010-2019 were screened. Exclusion criteria included the occurrence of immediate post-procedural intracranial haemorrhage (ICH). Hyperdense areas on iodine overlay maps were scored according to the Alberta Stroke Programme Early CT Score (ASPECTS), thus forming a CE-ASPECTS. Maximum parenchymal iodine concentration and maximum iodine concentration relative to the torcula were recorded. Follow-up imaging was reviewed for ICH. The primary outcome measure was the modified Rankin Scale (mRS) at 90 days. RESULTS Out of 651 records, 402 patients were included. CE was found in 318 patients (79%). Thirty-five patients developed ICH on follow-up imaging. Fourteen ICHs were symptomatic. Stroke progression occurred in 59 patients. Multivariable regression showed a significant association between decreasing CE-ASPECTS and the mRS at 90 days (adjusted (a)cOR: 1.10, 95% CI: 1.03-1.18), NIHSS at 24-48 h (aβ: 0.57, 95% CI: 0.29-0.84), stroke progression (aOR: 1.14, 95% CI: 1.03-1.26) and ICH (aOR: 1.21, 95% CI: 1.06-1.39), but not symptomatic ICH (aOR 1.19, 95% CI: 0.95-1.38). Iodine concentration was significantly associated with the mRS (acOR: 1.18, 95% CI: 1.06-1.32), NIHSS (aβ: 0.68, 95% CI: 0.30-1.06), ICH (aOR: 1.37, 95% CI: 1.04-1.81) and symptomatic ICH (aOR: 1.19, 95% CI: 1.02-1.38), but not stroke progression (aOR: 0.99, 95% CI: 0.86-1.15). Results of the analyses with relative iodine concentration were similar and did not improve prediction. CONCLUSIONS CE-ASPECTS and iodine concentration are both associated with short- and long-term stroke outcomes. CE-ASPECTS is likely a better predictor for stroke progression.
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Affiliation(s)
- Florentina ME Pinckaers
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Centre, Maastricht, The Netherlands
- School for Cardiovascular Diseases (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Max MG Mentink
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Centre, Maastricht, The Netherlands
| | | | - Wim H van Zwam
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Centre, Maastricht, The Netherlands
- School for Cardiovascular Diseases (CARIM), Maastricht University, Maastricht, The Netherlands
| | - Robert J van Oostenbrugge
- School for Cardiovascular Diseases (CARIM), Maastricht University, Maastricht, The Netherlands
- Department of Neurology, Maastricht University Medical Centre, Maastricht, The Netherlands
| | - Alida A Postma
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Centre, Maastricht, The Netherlands
- School for Mental Health and Neuroscience (MHENS), Maastricht University, Maastricht, The Netherlands
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Grkovski R, Acu L, Ahmadli U, Terziev R, Schubert T, Wegener S, Kulcsar Z, Husain S, Alkadhi H, Winklhofer S. A Novel Dual-Energy CT Method for Detection and Differentiation of Intracerebral Hemorrhage From Contrast Extravasation in Stroke Patients After Endovascular Thrombectomy : Feasibility and First Results. Clin Neuroradiol 2023; 33:171-177. [PMID: 35960327 PMCID: PMC10014653 DOI: 10.1007/s00062-022-01198-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Accepted: 07/07/2022] [Indexed: 11/28/2022]
Abstract
PURPOSE Dual-energy computed tomography (DECT) has been shown to be able to differentiate between intracranial hemorrhage (ICH) and extravasation of iodinated contrast media (contrast staining [CS]). TwinSpiral DECT is a recently introduced technique, which allows image acquisition at two different energy levels in two consecutive spiral scans. The aim of this study was to evaluate the feasibility and accuracy of TwinSpiral DECT to distinguish between ICH and CS after endovascular thrombectomy (EVT) in patients with acute ischemic stroke. METHODS This retrospective single-center study conducted between November 2019 and July 2020 included non-contrast TwinSpiral DECT scans (tube voltages 80 and 150Sn kVp) of 39 ischemic stroke patients (18 females, 21 males, mean age 69 ± 11 years) within 48-72 h after endovascular thrombectomy. Parenchymal hyperdensity was assessed for the presence of ICH or/and CS by two board certified and fellowship-trained, blinded and independent neuroradiologists using standard mixed images and virtual non-contrast (VNC) images with corresponding iodine maps from TwinSpiral DECT. Follow-up examinations (FU; CT or MRI) were used as a standard of reference. Sensitivity, specificity, and accuracy for the detection of ICH as well as the inter-reader agreement were calculated. RESULTS Parenchymal hyperdensities were detected in 17/39 (44%) patients. Using DECT, they were classified by both readers as ICH in 9 (53%), CS in 8 (47%), and mixture of both in 6 (35%) cases with excellent agreement (κ = 0.81, P < 0.0001). The sensitivity, specificity, and accuracy for the detection of ICH in DECT was 90% (95% confidence interval [CI]: 84-96%), 100% (95% CI 94-100%) and 95% (95% CI 89-100%), and in mixed images 90% (95% CI 84-96%), 86% (95% CI 80-92%) and 88% (95% CI 82-94%), respectively. Inter-reader agreement for detecting ICH on DECT compared to the mixed images was κ = 1.00 (P < 0.0001) vs. κ = 0.51 (P = 0.034). CONCLUSION TwinSpiral DECT demonstrates high accuracy and excellent specificity for differentiating ICH from CS in patients after mechanical thrombectomy due to acute ischemic stroke, and improves inter-reader agreement for detecting ICH compared to the standard mixed images.
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Affiliation(s)
- Risto Grkovski
- Department of Neuroradiology, Clinical Neuroscience Cente, University Hospital Zurich, University of Zurich, Zurich, Switzerland.,Faculty of Medicine, University Of Ljubljana, Ljubljana, Slovenia.,Department of Radiology, University Medical Centre Maribor, Maribor, Slovenia
| | - Leyla Acu
- Department of Neuroradiology, Clinical Neuroscience Cente, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Uzeyir Ahmadli
- Department of Neuroradiology, Clinical Neuroscience Cente, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Robert Terziev
- Department of Neuroradiology, Clinical Neuroscience Cente, University Hospital Zurich, University of Zurich, Zurich, Switzerland.,Department of Neurology, Clinical Neuroscience Cente, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Tilman Schubert
- Department of Neuroradiology, Clinical Neuroscience Cente, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Susanne Wegener
- Department of Neurology, Clinical Neuroscience Cente, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Zsolt Kulcsar
- Department of Neuroradiology, Clinical Neuroscience Cente, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Shakir Husain
- Department of Neuroradiology, Clinical Neuroscience Cente, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Hatem Alkadhi
- Institute of Diagnostic and Interventional Radiology, University Hospital Zurich, University of Zurich, Zurich, Switzerland
| | - Sebastian Winklhofer
- Department of Neuroradiology, Clinical Neuroscience Cente, University Hospital Zurich, University of Zurich, Zurich, Switzerland.
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8
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Chang GC, Ma DC, Li W, Qiu J, Sun XH, Zhao YG, Liu X, Zhao ZA, Liu L, Nguyen TN, Chen HS. Contrast enhancement by location and volume is associated with long-term outcome after thrombectomy in acute ischemic stroke. Sci Rep 2022; 12:16998. [PMID: 36216846 PMCID: PMC9551090 DOI: 10.1038/s41598-022-21276-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2022] [Accepted: 09/26/2022] [Indexed: 12/29/2022] Open
Abstract
Contrast enhancement (CE) on brain non-contrast computed tomography (NCCT) is common after endovascular thrombectomy (EVT) in patients with acute ischemic stroke (AIS), but its association with clinical outcomes is not well established. The current study aimed to investigate this relationship. We retrospectively reviewed consecutive patients with acute ischemic stroke who had hyperdensity on NCCT immediately after EVT for anterior circulation large vessel occlusion (LVO) from January 2016 to December 2019. We used ASPECTS combined with volume measurement by 3D reconstruction to estimate the extent and location of CE. Multivariable regression analysis was conducted to explore the risk factors associated with clinical outcome. In this study, 113 of 158 (71.52%) anterior circulation AIS-LVO patients had hyperdensity on brain NCCT. After strict inclusion and exclusion criteria, a total of 64 patients were enrolled in the final analysis. In logistic regression analysis, CE-ASPECTS, CE volume, CE at the caudate nucleus, M4 and M6 region were associated with 3-month poor functional outcome after adjusting for confounding factors. The conventional variable model was used for reference, including age, initial NIHSS, the procedure time, stent retriever passes, recanalization status and baseline ASPECTS, with AUC of 0.73. When combined with the above-named variables (conventional variables + CE-ASPECTS + CE volume + CE at caudate nucleus + CE at M4 region + CE at M6 region), the predictive power was significantly improved, with AUC of 0.87 (95% CI 0.78-0.95). The spatial location and volume of CE on NCCT obtained immediately after EVT were independent and strong predictors for poor outcome at 3-months in patients with AIS after excluding definite hemorrhage by 24-h follow up CT.
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Affiliation(s)
- Guo-Can Chang
- Department of Neurology, General Hospital of Northern Theater Command, Shen Yang, People's Republic of China
| | - Dai-Chao Ma
- Department of Neurology, General Hospital of Northern Theater Command, Shen Yang, People's Republic of China
- Department of Encephalopathy, Affiliated Hospital of Shaanxi University of Chinese Medicine, Xianyang, People's Republic of China
| | - Wei Li
- Department of Neurology, General Hospital of Northern Theater Command, Shen Yang, People's Republic of China
| | - Jin Qiu
- Department of Neurology, General Hospital of Northern Theater Command, Shen Yang, People's Republic of China
| | - Xian-Hui Sun
- Department of Neurology, General Hospital of Northern Theater Command, Shen Yang, People's Republic of China
| | - Yong-Gang Zhao
- Department of Neurology, General Hospital of Northern Theater Command, Shen Yang, People's Republic of China
| | - Xin Liu
- Department of Neurology, General Hospital of Northern Theater Command, Shen Yang, People's Republic of China
| | - Zi-Ai Zhao
- Department of Neurology, General Hospital of Northern Theater Command, Shen Yang, People's Republic of China
| | - Liang Liu
- Department of Neurology, General Hospital of Northern Theater Command, Shen Yang, People's Republic of China
| | - Thanh N Nguyen
- Neurology, Radiology, Boston Medical Center, Boston, MA, USA
| | - Hui-Sheng Chen
- Department of Neurology, General Hospital of Northern Theater Command, Shen Yang, People's Republic of China.
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Kauw F, Ding VY, Dankbaar JW, van Ommen F, Zhu G, Boothroyd DB, Wolman DN, Molvin L, de Jong HWAM, Kappelle LJ, Velthuis BK, Heit JJ, Wintermark M. Detection of Early Ischemic Changes with Virtual Noncontrast Dual-Energy CT in Acute Ischemic Stroke: A Noninferiority Analysis. AJNR Am J Neuroradiol 2022; 43:1259-1264. [PMID: 35953275 PMCID: PMC9451625 DOI: 10.3174/ajnr.a7600] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Accepted: 06/17/2022] [Indexed: 01/26/2023]
Abstract
BACKGROUND AND PURPOSE Dual-energy virtual NCCT has the potential to replace conventional NCCT to detect early ischemic changes in acute ischemic stroke. In this study, we evaluated whether virtual NCCT is noninferior compared with standard linearly blended NCCT, a surrogate of conventional NCCT, regarding the detection of early ischemic changes with ASPECTS. MATERIALS AND METHODS Adult patients who presented with suspected acute ischemic stroke and who underwent dual-energy NCCT and CTA and brain MR imaging within 48 hours were included. Standard linearly blended images were reconstructed to match a conventional NCCT. Virtual NCCT images were reconstructed from CTA. ASPECTS was evaluated on conventional NCCT, virtual NCCT, and DWI, which served as the reference standard. Agreement between CT assessments and the reference standard was evaluated with the Lin concordance correlation coefficient. Noninferiority was assessed with bootstrapped estimates of the differences in ASPECTS between conventional and virtual NCCT with 95% CIs. RESULTS Of the 193 included patients, 100 patients (52%) had ischemia on DWI. Compared with the reference standard, the ASPECTS concordance correlation coefficient for conventional and virtual NCCT was 0.23 (95% CI, 0.15-0.32) and 0.44 (95% CI, 0.33-0.53), respectively. The difference in the concordance correlation coefficient between virtual and conventional NCCT was 0.20 (95% CI, 0.01-0.39) and did not cross the prespecified noninferiority margin of -0.10. CONCLUSIONS Dual-energy virtual NCCT is noninferior compared with conventional NCCT for the detection of early ischemic changes with ASPECTS.
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Affiliation(s)
- F Kauw
- From the Departments of Radiology (F.K., F.v.O., G.Z., D.N.W., L.M., J.J.H., M.W.)
- Departments of Radiology (F.K., J.W.D., F.v.O., H.W.A.M.d.J., B.K.V.)
- Neurology (F.K., L.J.K.), University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
| | - V Y Ding
- Medicine (V.Y.D., D.B.B.), Stanford University, Stanford, California
| | - J W Dankbaar
- Departments of Radiology (F.K., J.W.D., F.v.O., H.W.A.M.d.J., B.K.V.)
| | - F van Ommen
- From the Departments of Radiology (F.K., F.v.O., G.Z., D.N.W., L.M., J.J.H., M.W.)
- Departments of Radiology (F.K., J.W.D., F.v.O., H.W.A.M.d.J., B.K.V.)
| | - G Zhu
- From the Departments of Radiology (F.K., F.v.O., G.Z., D.N.W., L.M., J.J.H., M.W.)
| | - D B Boothroyd
- Medicine (V.Y.D., D.B.B.), Stanford University, Stanford, California
| | - D N Wolman
- From the Departments of Radiology (F.K., F.v.O., G.Z., D.N.W., L.M., J.J.H., M.W.)
| | - L Molvin
- From the Departments of Radiology (F.K., F.v.O., G.Z., D.N.W., L.M., J.J.H., M.W.)
| | - H W A M de Jong
- Departments of Radiology (F.K., J.W.D., F.v.O., H.W.A.M.d.J., B.K.V.)
| | - L J Kappelle
- Neurology (F.K., L.J.K.), University Medical Center Utrecht, Utrecht University, Utrecht, the Netherlands
| | - B K Velthuis
- Departments of Radiology (F.K., J.W.D., F.v.O., H.W.A.M.d.J., B.K.V.)
| | - J J Heit
- From the Departments of Radiology (F.K., F.v.O., G.Z., D.N.W., L.M., J.J.H., M.W.)
| | - M Wintermark
- From the Departments of Radiology (F.K., F.v.O., G.Z., D.N.W., L.M., J.J.H., M.W.)
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10
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Ng FC, Yassi N, Sharma G, Brown SB, Goyal M, Majoie CBLM, Jovin TG, Hill MD, Muir KW, Saver JL, Guillemin F, Demchuk AM, Menon BK, San Roman L, White P, van der Lugt A, Ribo M, Bracard S, Mitchell PJ, Davis SM, Sheth KN, Kimberly WT, Campbell BCV. Correlation Between Computed Tomography-Based Tissue Net Water Uptake and Volumetric Measures of Cerebral Edema After Reperfusion Therapy. Stroke 2022; 53:2628-2636. [PMID: 35450438 DOI: 10.1161/strokeaha.121.037073] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Cerebral edema after large hemispheric infarction is associated with poor functional outcome and mortality. Net water uptake (NWU) quantifies the degree of hypoattenuation on unenhanced-computed tomography (CT) and is increasingly used to measure cerebral edema in stroke research. Hemorrhagic transformation and parenchymal contrast staining after thrombectomy may confound NWU measurements. We investigated the correlation of NWU measured postthrombectomy with volumetric markers of cerebral edema and association with functional outcomes. METHODS In a pooled individual patient level analysis of patients presenting with anterior circulation large hemispheric infarction (core 80-300 mL or Alberta Stroke Program Early CT Score ≤5) in the HERMES (Highly Effective Reperfusion Evaluated in Multiple Endovascular Stroke trials) data set, cerebral edema was defined as the volumetric expansion of the ischemic hemisphere expressed as a ratio to the contralateral hemisphere(rHV). NWU and midline-shift were compared with rHV as the reference standard on 24-hour follow-up CT, adjusted for hemorrhagic transformation and the use of thrombectomy. Association between edema markers and day 90 functional outcomes (modified Rankin Scale) was assessed using ordinal logistic regression. RESULTS Overall (n=144), there was no correlation between NWU and rHV (rs=0.055, P=0.51). In sub-group analyses, a weak correlation between NWU with rHV was observed after excluding patients with any degree of hemorrhagic transformation (rs=0.211, P=0.015), which further improved after excluding thrombectomy patients (rs=0.453, P=0.001). Midline-shift correlated strongly with rHV in all sub-group analyses (rs>0.753, P=0.001). Functional outcome at 90 days was negatively associated with rHV (adjusted common odds ratio, 0.46 [95% CI, 0.32-0.65]; P<0.001) and midline-shift (adjusted common odds ratio, 0.85 [95% CI, 0.78-0.92]; P<0.001) but not NWU (adjusted common odds ratio, 1.00 [95% CI, 0.97-1.03]; P=0.84), adjusted for age, baseline National Institutes of Health Stroke Scale, and thrombectomy. Prognostic performance of NWU improved after excluding patients with hemorrhagic transformation and thrombectomy (adjusted odds ratio, 0.90 [95% CI, 0.80-1.02]; P=0.10). CONCLUSIONS NWU correlated poorly with conventional markers of cerebral edema and was not associated with clinical outcome in the presence of hemorrhagic transformation and thrombectomy. Measuring NWU postthrombectomy requires validation before implementation into clinical research. At present, the use of NWU should be limited to baseline CT, or follow-up CT only in patients without hemorrhagic transformation or treatment with thrombectomy.
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Affiliation(s)
- Felix C Ng
- Melbourne Brain Centre, Royal Melbourne Hospital, University of Melbourne, Parkville, Australia (F.C.N., N.Y., G.S., S.M.D., B.C.V.C.).,Austin Health, Heidelberg, Australia (F.C.N.)
| | - Nawaf Yassi
- Population Health and Immunity Division, The Walter and Eliza Hall Institute of Medical Research, Parkville, Australia (N.Y.)
| | - Gagan Sharma
- Melbourne Brain Centre, Royal Melbourne Hospital, University of Melbourne, Parkville, Australia (F.C.N., N.Y., G.S., S.M.D., B.C.V.C.)
| | | | - Mayank Goyal
- Department of Radiology, University of Calgary, Foothills Hospital, AB, Canada (M.G.)
| | - Charles B L M Majoie
- Department of Radiology and Nuclear Medicine, Amsterdam University Medical Centers, location AMC, the Netherlands (C.B.L.M.M.)
| | - Tudor G Jovin
- Cooper Neurological Institute, Cooper University Health Care, Camden, NJ (T.G.J.)
| | - Michael D Hill
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Foothills Hospital, AB, Canada (M.D.H., A.M.D., B.K.M.)
| | - Keith W Muir
- Institute of Neuroscience & Psychology, University of Glasgow, Queen Elizabeth University Hospital, United Kingdom (K.W.M.)
| | - Jeffrey L Saver
- Department of Neurology and Comprehensive Stroke Center, David Geffen School of Medicine at the University of California, Los Angeles, California Stanford Stroke Center, Stanford University (J.L.S.)
| | - Francis Guillemin
- Clinical Investigation Centre-Clinical Epidemiology INSERM 1433, University of Lorraine and University Hospital of Nancy, France (F.G.)
| | - Andrew M Demchuk
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Foothills Hospital, AB, Canada (M.D.H., A.M.D., B.K.M.)
| | - Bijoy K Menon
- Department of Clinical Neurosciences, Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Foothills Hospital, AB, Canada (M.D.H., A.M.D., B.K.M.)
| | - Luis San Roman
- Department of Radiology, Hospital Clínic, Barcelona, Spain (L.S.R.)
| | - Philip White
- Institute of Neuroscience, Newcastle University, Newcastle upon Tyne, United Kingdom (P.W.)
| | - Aad van der Lugt
- Department of Radiology and Nuclear Medicine, Erasmus MC University Medical Center, Rotterdam, the Netherlands (A.v.d.L.)
| | - Marc Ribo
- Department of Neurology, Hospital Vall d'Hebron, Barcelona, Spain (M.R.)
| | - Serge Bracard
- Department of Diagnostic and Interventional Neuroradiology, Université de Lorraine, Inserm, IADI, CHRU Nancy, France (S.B.)
| | - Peter J Mitchell
- Department of Radiology, Royal Melbourne Hospital, University of Melbourne, Parkville, Australia (P.J.M.)
| | - Stephen M Davis
- Melbourne Brain Centre, Royal Melbourne Hospital, University of Melbourne, Parkville, Australia (F.C.N., N.Y., G.S., S.M.D., B.C.V.C.)
| | - Kevin N Sheth
- Department of Neurology, Yale New Haven Hospital, CT (K.N.S.)
| | - W Taylor Kimberly
- Center for Genomic Medicine and Department of Neurology, Massachusetts General Hospital, Boston (W.T.K.)
| | - Bruce C V Campbell
- Melbourne Brain Centre, Royal Melbourne Hospital, University of Melbourne, Parkville, Australia (F.C.N., N.Y., G.S., S.M.D., B.C.V.C.)
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11
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Comparative Studies of Cerebral Reperfusion Injury in the Posterior and Anterior Circulations After Mechanical Thrombectomy. Transl Stroke Res 2022; 13:556-564. [PMID: 35006533 PMCID: PMC9232466 DOI: 10.1007/s12975-021-00977-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Revised: 12/10/2021] [Accepted: 12/13/2021] [Indexed: 11/17/2022]
Abstract
Cerebral reperfusion injury is the major complication of mechanical thrombectomy (MT) for acute ischemic stroke (AIS). Contrast extravasation (CE) and intracranial hemorrhage (ICH) are the key radiographical features of cerebral reperfusion injury. The aim of this study was to investigate CE and ICH after MT in the anterior and posterior circulation, and their effect on functional outcome. This is a retrospective study of all consecutive patients who were treated with MT for AIS at University of California Irvine Medical Center between January 1, 2014, and December 31, 2017. Patient characteristics, clinical features, procedural variables, contrast extravasation, ICH, and outcomes after MT were analyzed. A total of 131 patients with anterior circulation (AC) stroke and 25 patients with posterior circulation (PC) stroke underwent MT during the study period. There was no statistically significant difference in admission NIHSS score, blood pressure, rate of receiving intravenous tPA, procedural variables, contrast extravasation, and symptomatic ICH between the 2 groups. Patients with PC stroke had a similar rate of favorable outcome (mRS 0–2) but significantly higher mortality (40.0% vs. 10.7%, p < 0.01) than patients with AC stroke. Multivariate regression analysis identified initial NIHSS score (OR 1.1, CI 1.0–1.2, p = 0.01), number of passes with stent retriever (OR 2.1, CI 1.3–3.6, p < 0.01), and PC stroke (OR 9.3, CI 2.5–35.1, p < 0.01) as independent risk factors for death. There was no significant difference in functional outcomes between patients with and without evidence of cerebral reperfusion injury after MT. We demonstrated that AC and PC stroke had similar rates of cerebral reperfusion injury and favorable outcome after MT. Cerebral reperfusion injury is not a significant independent risk factor for poor functional outcome.
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12
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Wang C, Zhu Q, Cui T, Wang L, Yang T, Hao Z, Wu S, Zheng H, Hu F, Wu B. Early Prediction of Malignant Edema After Successful Recanalization in Patients with Acute Ischemic Stroke. Neurocrit Care 2021; 36:822-830. [PMID: 34751418 DOI: 10.1007/s12028-021-01380-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 10/13/2021] [Indexed: 02/05/2023]
Abstract
BACKGROUND Postinterventional cerebral hyperdensities are common on non-contrast-enhanced computed tomography (CT) after endovascular thrombectomy in patients with acute ischemic stroke, which may reflect blood-brain barrier damage. The disruption of the blood-brain barrier may lead to malignant brain edema. The relationship between the extent of postinterventional cerebral hyperdensities and malignant brain edema is unclear. METHODS Patients with middle cerebral artery territory infarction and successful recanalization were consecutively enrolled. Postinterventional non-contrast-enhanced CT was performed to evaluate postinterventional cerebral hyperdensities within 24 h after endovascular thrombectomy. On the basis of the areas of the Alberta Stroke Program Early CT Score, we devised the Hyperdensity on CT Score to evaluate the extent of postinterventional cerebral hyperdensities. The primary outcome was malignant brain edema, defined as the development of clinical signs of herniation (including a decrease in consciousness and/or anisocoria), accompanied by imaging evidence of brain swelling. The component of postinterventional cerebral hyperdensities was divided into contrast staining and hemorrhage on the basis of persistency. RESULTS Three hundred sixty patients were included (50.6% male, mean age 67.9 years), of whom 247 (68.6%) developed postinterventional cerebral hyperdensities and 66 (18.3%) developed malignant brain edema. After adjustment for confounders, including the component of postinterventional cerebral hyperdensities, the extent of postinterventional cerebral hyperdensities assessed by the Hyperdensity on CT Score was significantly associated with malignant brain edema (odds ratio 1.46, 95% confidence interval 1.20-1.77, p < 0.001). A Hyperdensity on CT Score greater than 3 had a sensitivity of 0.73 and a specificity of 0.87 for predicting malignant brain edema. CONCLUSIONS The extent of postinterventional cerebral hyperdensities on postinterventional non-contrast-enhanced CT was associated with malignant brain edema. The Hyperdensity on CT Score could be used to predict malignant brain edema regardless of the component of postinterventional cerebral hyperdensities.
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Affiliation(s)
- Changyi Wang
- Department of Neurology, Center of Cerebrovascular Diseases, West China Hospital, Sichuan University, Chengdu, Sichuan, China
- Departement of Rehabilitation Medicine Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Qiange Zhu
- The Second Department of Neurology, Shaanxi Provincial People's Hospital, Xi'an, Shaanxi, China
| | - Ting Cui
- Department of Neurology, Center of Cerebrovascular Diseases, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Lu Wang
- Departement of Rehabilitation Medicine Center, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Tang Yang
- Department of Neurology, Center of Cerebrovascular Diseases, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Zilong Hao
- Department of Neurology, Center of Cerebrovascular Diseases, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Simiao Wu
- Department of Neurology, Center of Cerebrovascular Diseases, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Hongbo Zheng
- Department of Neurology, Center of Cerebrovascular Diseases, West China Hospital, Sichuan University, Chengdu, Sichuan, China
| | - Fayun Hu
- Department of Neurology, Center of Cerebrovascular Diseases, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
| | - Bo Wu
- Department of Neurology, Center of Cerebrovascular Diseases, West China Hospital, Sichuan University, Chengdu, Sichuan, China.
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