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Hosoo H, Ito Y, Marushima A, Hayakawa M, Masumoto T, Ishikawa E, Matsumaru Y. Image quality improvements for brain soft tissue in neuro-endovascular treatments: A novel dual-axis "butterfly" trajectory for optimized Cone-Beam CT. Eur J Radiol 2023; 160:110713. [PMID: 36716548 DOI: 10.1016/j.ejrad.2023.110713] [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] [Received: 11/08/2022] [Revised: 01/06/2023] [Accepted: 01/20/2023] [Indexed: 01/26/2023]
Abstract
PURPOSE Cone-beam computed tomography (CBCT) is useful in the diagnosis of complications after neuro-endovascular treatment. However, the image quality of conventional CBCT is inferior to that of conventional CT. To solve this problem, a dual-axis butterfly CBCT available with an angiography suite has been developed. This study aimed to evaluate the image quality of this dual-axis butterfly CBCT compared to the conventional CBCT in the same patient. METHOD We prospectively included patients who underwent scheduled neuro-endovascular treatment and performed conventional CBCT and novel dual-axis butterfly CBCT as a postoperative examination. We evaluated artifacts, brain contrast, and cortico-medullary junctions on a scoring system using a 5-point scale in which lower scores indicate better image quality. In addition, the white matter/gray matter ratio was calculated in selected brain lobe regions. RESULTS Forty-seven cases (94 paired images) were enrolled. The novel dual-axis butterfly CBCT had significantly fewer supratentorial and infratentorial artifacts in the artifact evaluation. Similarly, contrast and cortico-medullary junction discrimination in the cerebral hemispheres scored significantly better in the butterfly scan in all regions. The white matter/gray matter ROI ratio was significantly higher in the novel dual-axis butterfly CBCT in the frontal and occipital lobes but not in the temporal lobe. CONCLUSIONS Compared to conventional CBCT, the novel dual-axis butterfly CBCT showed supratentorial and infratentorial artifact reduction as well as improved contrast with the brain parenchyma and cerebrospinal fluid space and white matter/gray matter discrimination ability.
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Affiliation(s)
- Hisayuki Hosoo
- Division of Stroke Prevention and Treatment, Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Ibaraki, Japan; Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Ibaraki, Japan
| | - Yoshiro Ito
- Division of Stroke Prevention and Treatment, Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Ibaraki, Japan; Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Ibaraki, Japan
| | - Aiki Marushima
- Division of Stroke Prevention and Treatment, Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Ibaraki, Japan; Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Ibaraki, Japan
| | - Mikito Hayakawa
- Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Ibaraki, Japan
| | | | - Eiichi Ishikawa
- Division of Stroke Prevention and Treatment, Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Ibaraki, Japan
| | - Yuji Matsumaru
- Division of Stroke Prevention and Treatment, Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Ibaraki, Japan; Department of Neurosurgery, Faculty of Medicine, University of Tsukuba, Ibaraki, Japan.
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LaGrange DD, Wanke I, Machi P, Bernava G, Vargas M, Botta D, Berberat J, Muster M, Platon A, Poletti PA, Lövblad KO. Multimodality Characterization of the Clot in Acute Stroke. Front Neurol 2022; 12:760148. [PMID: 34970209 PMCID: PMC8712945 DOI: 10.3389/fneur.2021.760148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 11/17/2021] [Indexed: 11/26/2022] Open
Abstract
Aim: Current treatment of occluded cerebral vessels can be done by a variety of endovascular techniques. Sometimes, the clot responds in varying degrees to the treatment chosen. The Ex vivo characterization of the clot occluding the arteries in acute ischemic stroke can help in understanding the underlying imaging features obtained from pre-treatment brain scans. For this reason, we explored the potential of microCT when combined with electron microscopy for clot characterization. Results were compared to the clinical CT findings. Methods: 16 patients (9 males, 8 females, age range 54–93 years) who were referred to our institution for acute stroke underwent dual-source CT. Results: Clinical CT clots were seen as either iso or hyperdense. This was corroborated with micro-CT, and electron microscopy can show the detailed composition. Conclusion: MicroCT values can be used as an indicator for red blood cells-rich composition of clots. Meaningful information regarding the clot composition and modalities of embedding along the stent retrievers can be obtained through a combination of microCT and electron microscopy.
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Affiliation(s)
- Daniela Dumitriu LaGrange
- Division of Diagnostic and Interventional Neuroradiology, Diagnostic Department, HUG Geneva University Hospitals, Genève, Switzerland
| | - Isabel Wanke
- Division of Neuroradiology, Zentrum für Neuroradiologie, Klinik Hirslanden, Zurich, Switzerland.,Swiss Neuroradiology Institute, Zurich, Switzerland.,Division of Neuroradiology, Institute of Diagnostic and Interventional Radiology and Neuroradiology, University of Essen, Essen, Germany
| | - Paolo Machi
- Division of Diagnostic and Interventional Neuroradiology, Diagnostic Department, HUG Geneva University Hospitals, Genève, Switzerland
| | - Gianmarco Bernava
- Division of Diagnostic and Interventional Neuroradiology, Diagnostic Department, HUG Geneva University Hospitals, Genève, Switzerland
| | - Maria Vargas
- Division of Diagnostic and Interventional Neuroradiology, Diagnostic Department, HUG Geneva University Hospitals, Genève, Switzerland
| | - Daniele Botta
- Division of Radiology, Diagnostic Department, Geneva University Hospitals, Genève, Switzerland
| | - Jatta Berberat
- Division of Neuroradiology, Zentrale Medizinische Dienste, Kantonsspital Aarau, Aarau, Switzerland
| | - Michel Muster
- Division of Diagnostic and Interventional Neuroradiology, Diagnostic Department, HUG Geneva University Hospitals, Genève, Switzerland
| | - Alexandra Platon
- Division of Radiology, Diagnostic Department, Geneva University Hospitals, Genève, Switzerland
| | | | - Karl-Olof Lövblad
- Division of Diagnostic and Interventional Neuroradiology, Diagnostic Department, HUG Geneva University Hospitals, Genève, Switzerland
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Imaging Clot Characteristics in Stroke and its Possible Implication on Treatment. Clin Neuroradiol 2019; 30:27-35. [DOI: 10.1007/s00062-019-00841-w] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Accepted: 09/17/2019] [Indexed: 12/11/2022]
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Hsu CCT, Kwan GNC, Hapugoda S, Craigie M, Watkins TW, Haacke EM. Susceptibility weighted imaging in acute cerebral ischemia: review of emerging technical concepts and clinical applications. Neuroradiol J 2017; 30:109-119. [PMID: 28424015 DOI: 10.1177/1971400917690166] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Susceptibility weighted imaging (SWI) is an essential magnetic resonance imaging sequence in the assessment of acute ischemic stroke. In this article, we discuss the physics principals and clinical application of conventional SWI and multi-echo SWI sequences. We review the research evidence and practical approach of SWI in acute ischemic stroke by focusing on the detection and characterization of thromboembolism in the cerebral circulation. In addition, we discuss the role of SWI in the assessment of neuroparenchyma by depiction of asymmetric hypointense cortical veins in the ischemic territory (surrogate tissue perfusion), detection of existing microbleeds before stroke treatment and monitoring for hemorrhagic transformation post-treatment. In conclusion, the SWI sequence complements other parameters in the stroke magnetic resonance imaging protocol and understanding of the research evidence is vital for practising stroke neurologists and neuroradiologists.
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Affiliation(s)
- Charlie Chia-Tsong Hsu
- 1 Department of Medical Imaging, Princess Alexandra Hospital, Australia.,2 Department of Medical Imaging, University of Toronto, Toronto, Ontario, Canada
| | - Gigi Nga Chi Kwan
- 1 Department of Medical Imaging, Princess Alexandra Hospital, Australia
| | | | - Michelle Craigie
- 1 Department of Medical Imaging, Princess Alexandra Hospital, Australia
| | | | - E Mark Haacke
- 3 Departments of Radiology and Biomedical Engineering, Wayne State University, USA
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Ernst M, Romero JM, Buhk JH, Kemmling A, Fiehler J, Groth M. Sensitivity of visual and quantitative detection of middle cerebral artery occlusion on non-contrast-enhanced computed tomography. Neuroradiology 2014; 56:1063-8. [PMID: 25274137 DOI: 10.1007/s00234-014-1443-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Accepted: 09/23/2014] [Indexed: 10/24/2022]
Abstract
INTRODUCTION This study aims to investigate diagnostic sensitivity and reliability for the detection of middle cerebral artery occlusion (MCAO) on non-contrast-enhanced computed tomography (NECT) by visual assessment (VA), Hounsfield unit (HU) measurement, calculation of the Hounsfield unit/hematocrit (HU/Hct) ratio, and combination of visual assessment and attenuation measurement (VA + HU). METHODS NECT of 18 patients with angiographically proven MCAO and 18 patients without MCAO were reviewed by two blinded observers. Visual assessment of presence or absence of a hyperdense sign was followed by HU measurement of both middle cerebral arteries (MCA). Sensitivity, specificity, positive predictive value, and negative predictive value were calculated for VA, HU measurement, HU/Hct ratio, and VA + HU measurement. Receiver operating characteristic curve analysis (ROC) was performed to determine the optimal cut-off values for MCAO using attenuation measurements or HU/Hct ratio. RESULTS Diagnostic sensitivity/specificity was 63%/91% for VA, 56%/88% for attenuation measurement, 68 %/81 % for HU/Hct ratio, and 75%/78% for VA + HU. ROC curve analysis revealed cut-off values of >42.5 HU for attenuation measurements and >1.12 HU/Hct for HU/Hct ratio. CONCLUSION Combination of visual assessment with additional attenuation measurement with a cut-off value of 42.5 HU is recommended for most sensitive and reliable detection of MCAO on NECT.
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Affiliation(s)
- M Ernst
- Center for Radiology and Endoscopy Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Haus Ost 22 (O 22) Martinistr 52, 20246, Hamburg, Germany,
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Ledezma CJ, Fiebach JB, Wintermark M. Modern imaging of the infarct core and the ischemic penumbra in acute stroke patients: CT versus MRI. Expert Rev Cardiovasc Ther 2014; 7:395-403. [DOI: 10.1586/erc.09.7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Bal S, Goyal M, Smith E, Demchuk AM. Central nervous system imaging in diabetic cerebrovascular diseases and white matter hyperintensities. HANDBOOK OF CLINICAL NEUROLOGY 2014; 126:291-315. [PMID: 25410230 DOI: 10.1016/b978-0-444-53480-4.00021-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Diabetes mellitus is an important vascular risk factor for cerebrovascular disease. This occurs through pathophysiologic changes to the microcirculation as arteriolosclerosis and to the macrocirculation as large artery atherosclerosis. Imaging techniques can provide detailed visualization of the cerebrovasculature using CT (computed tomography) angiography and MR (magnetic resonance) angiography. Newer techniques focused on advanced parenchymal imaging include CT perfusion, quantitative MRI, and diffusion tensor imaging; each identifies brain lesion burden due to diabetes mellitus. These imaging approaches have provided insights into the diabetes mellitus brain and cerebral circulation pathophysiology. Imaging has taught us that diabetics develop cerebral atrophy, silent infarcts, and white matter disease more rapidly than other patient populations. Longitudinal studies are needed to quantify the rate and extent of such structural brain and blood vessel changes and how they relate to cognitive decline. Diabetes prevention and treatment strategies will then be possible to slow the development of such changes.
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Affiliation(s)
- Simerpreet Bal
- Department of Clinical Neurosciences and Radiology, Foothills Medical Centre, Calgary, Alberta, Canada
| | - Mayank Goyal
- Department of Clinical Neurosciences and Radiology, Foothills Medical Centre, Calgary, Alberta, Canada
| | - Eric Smith
- Department of Clinical Neurosciences and Radiology, Foothills Medical Centre, Calgary, Alberta, Canada
| | - Andrew M Demchuk
- Department of Clinical Neurosciences and Radiology, Foothills Medical Centre, Calgary, Alberta, Canada.
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Gokhale S, Graffagnino C. Hyperdense posterior cerebral artery sign in a setting of spontaneous vertebral artery dissection: a blessing in disguise? Med Princ Pract 2014; 23:86-8. [PMID: 23900019 PMCID: PMC5586820 DOI: 10.1159/000351694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2012] [Accepted: 04/29/2013] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE To report a case of a hyperdense posterior cerebral artery (PCA) sign in the setting of spontaneous vertebral artery dissection. CLINICAL PRESENTATION AND INTERVENTION A 28-year-old, previously healthy female presented with rapidly progressive coma. A noncontrast computerized tomographic (CT) scan showed a hyperdense PCA sign, which prompted an urgent arteriogram. She was found to have spontaneous vertebral artery dissection with an occluding thrombus. She underwent intra-arterial thrombolysis with tissue plasminogen activator. Follow-up magnetic resonance imaging showed an area of acute infarction in the medial temporal and occipital regions corresponding to the area supplied by the left PCA. The patient was started on systemic anticoagulation therapy with intravenous heparin. She showed slow and continued recovery but was left with significant neurological deficits that required posthospital discharge to a long-term rehabilitation facility. CONCLUSION This case showed that the hyperdense PCA sign on a noncontrast CT scan necessitated an emergent CT angiogram that showed vertebral artery dissection and a devastating vascular occlusion. Hence, we suggest an early intervention that may allow for potential revascularization therapy.
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Affiliation(s)
- Sankalp Gokhale
- *Sankalp Gokhale, MD, Department of Neurology, Duke University Hospital, Durham, NC 27710 (USA), E-Mail
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Takhtani D, Dundamadappa S, Almast J. Role of noncontrast head CT in the assessment of vascular abnormalities in the emergency room. Emerg Radiol 2013; 20:529-41. [PMID: 23739799 DOI: 10.1007/s10140-013-1136-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2013] [Accepted: 05/27/2013] [Indexed: 11/28/2022]
Abstract
Noncontrast CT of the head is a widely used noninvasive investigation for a variety of acute and chronic neurological conditions. Since CT head without contrast is usually the first and often the only investigation in the emergency room for many neurological symptoms, it is imperative to detect subtle vascular changes, which in many patients can be life-saving. The vascular abnormalities may present with increased density and/or size of the vessels, filling defects, and be associated with parenchymal and bony changes. In this article, we present examples of several vascular pathologies which can be identified on the noncontrast CT of the head, and learn imaging and interpretation techniques to help recognize what often are nebulous changes. While some of the findings are diagnostic by themselves and others subtle, any suspicious abnormality should be followed with dedicated vascular imaging such as CT/MR angiogram, venogram, or catheter angiogram for confirmation and better characterization.
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Affiliation(s)
- Deepak Takhtani
- University of Massachusetts Medical School, UMass Memorial Hospital, Worcester, MA, 01655, USA,
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Connell L, Koerte IK, Laubender RP, Morhard D, Linn J, Becker HC, Reiser M, Brueckmann H, Ertl-Wagner B. Hyperdense basilar artery sign—a reliable sign of basilar artery occlusion. Neuroradiology 2011; 54:321-7. [DOI: 10.1007/s00234-011-0887-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2011] [Accepted: 04/29/2011] [Indexed: 10/18/2022]
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Lopes L. Perfusion CT: Additional Diagnostic and Clinical Information in MCA Stroke. Neuroradiol J 2010; 23:651-8. [DOI: 10.1177/197140091002300602] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Accepted: 09/04/2010] [Indexed: 11/16/2022] Open
Affiliation(s)
- L. Lopes
- Neuroradiology Unit, Radiology Department, Prof. Dr. Fernando Fonseca Hospital; Lisbon, Portugal
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Jensen-Kondering U, Riedel C, Jansen O. Hyperdense artery sign on computed tomography in acute ischemic stroke. World J Radiol 2010; 2:354-7. [PMID: 21160697 PMCID: PMC2999334 DOI: 10.4329/wjr.v2.i9.354] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/29/2010] [Revised: 08/24/2010] [Accepted: 08/31/2010] [Indexed: 02/06/2023] Open
Abstract
Despite the advent and growing availability of magnetic resonance imaging, the imaging modality of choice in the acute care of stroke patients in many institutions remains computed tomography. The hyperdense artery sign is the earliest marker of acute ischemic stroke. In this short review, we discuss the pathology, incidence, clinical aspects, imaging findings, significance and future questions that need to be addressed concerning this important sign.
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Tan X, Guo Y. Hyperdense basilar artery sign diagnoses acute posterior circulation stroke and predicts short-term outcome. Neuroradiology 2010; 52:1071-8. [PMID: 20358365 DOI: 10.1007/s00234-010-0682-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2009] [Accepted: 03/09/2010] [Indexed: 10/19/2022]
Abstract
INTRODUCTION It is well established that the hyperdense middle cerebral artery sign is a specific marker for early ischemia in anterior circulation. However, little is known about the hyperdense basilar artery sign (HDBA) in posterior circulation. Our aim was to determine whether the HDBA sign has utility in early diagnosis of acute posterior circulation stroke and prediction of short-term outcome. METHODS Three-blinded readers examined unenhanced computed tomography scans for the HDBA sign, and materials were classified into two groups according to this sign. Vascular risk factors, admission and discharge National Institute of Health Stroke Scale (NIHSS) scores, short-term outcome, and radiological findings between the two groups were compared. RESULTS One hundred and twenty-six cases of acute posterior circulation stroke (PCS) were included in the study. No statistically significant differences were found in risk factors of ischemic stroke, except atrial fibrillation (P=0.025). Admission and discharge NIHSS scores for the positive HDBA group were significantly higher than scores for the negative HDBA group (P=0.001, 0.002, respectively). The infarction territory for the positive HDBA group was mainly multi-region in nature (51.6%, P<0.001), while the negative HDBA group showed mainly middle territory infarction. Significant independent predictors of short-term outcome included the HDBA sign (P<0.001) and admission NIHSS scores (P<0.001). CONCLUSION Approximately half of the HDBA patients showed multi-region infarction and a serious neurological symptom. Based on our results, this sign might not only be helpful in early diagnosis of acute PCS but also be able to correlate with a poor short-term outcome.
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Affiliation(s)
- Xiaoping Tan
- Department of Neurology, Shengjing Hospital, Affiliated Hospital of China Medical University at Shenyang, 39 Hua Xiang Road, Tie Xi District, Shenyang, China
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Computed tomography in acute ischemic stroke. Neuroradiology 2009; 52:175-87. [PMID: 19953234 DOI: 10.1007/s00234-009-0633-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2009] [Accepted: 11/16/2009] [Indexed: 10/20/2022]
Abstract
Stroke remains the third most important cause of mortality in industrialized countries; this has prompted research for improvements in both diagnostic and therapeutic strategies for patients with signs of acute cerebral ischemia. Over the last decade, there has been a parallel in progress in techniques in both diagnostic and therapeutic options. While previously only used for excluding hemorrhage, imaging now has the possibility to detect ischemia, vascular occlusion, as well as detect tissue at risk in one setting. It should also allow to monitor treatment and predict/exclude therapeutic complications. Parallel to advances in magnetic resonance imaging of stroke, computed tomography has improved immensely over the last decade due to the development of CT scanners that are faster and that allow to acquire studies such as CT perfusion or CT angiography in a reliable way. CT can detect many signs that might help us detect impending signs of massive infarction, but we still lack the experience to use these alone to prevent a patient from benefitting from possible therapy.
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Abstract
A multimodal CT protocol provides a comprehensive noninvasive survey of acute stroke patients with accurate demonstration of the site of arterial occlusion and its hemodynamic tissue status. It combines widespread availability with the ability to provide functional characterization of cerebral ischemia, and could potentially allow more accurate selection of candidates for acute stroke reperfusion therapy. This article discusses the individual components of multimodal CT and addresses the potential role of a combined multimodal CT stroke protocol in acute stroke therapy.
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Affiliation(s)
- Carlos J Ledezma
- Morristown Memorial Hospital, Department of Radiology, 100 Madison Avenue, Morristown, NJ 07962, USA
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Abstract
OBJECTIVES The current management of acute ischemic stroke is intravenous (IV) recombinant tissue plasminogen activator (rtPA). The presence of a hyperdense middle cerebral artery sign (HMCAS) on pre-treatment head computed tomogram (CT) is considered a poor prognostic sign. We compared the clinical outcome in IV rtPA-treated patients with and without a HMCAS. DESIGN Retrospective analysis of prospectively collected cases treated with IV rtPA within three hours. Inclusion criteria were the presence of: i) an anterior circulation stroke; ii) a pre-treatment CT available; iii) a pre-treatment National Institutes of Health (NIH) stroke scale (NIHSS) score; and iv) a modified Rankin Score (mRS) at three months. RESULTS One hundred and thirty patients were eligible for the analysis, 64 (49%) had a HMCAS. The HMCAS group had a trend toward a higher mean (+/-SD) pre-treatment NIHSS score compared to the non-HMCAS group (13.9+/-6 vs. 12.2+/-6; p=0.12). Accordingly, there were more patients with severe strokes (NIHSS>10) in the HMCAS group compared to the non-HMCAS one (48/64=75% vs. 35/66=53%; p=0.009). The mean (+/-SD) NIHSS score 24 hours after treatment was 10.6 (+/-8) in the HMCAS group and 8.3 (+/-7) in the non-HMCAS group (p=0.08). In a multiple logistic regression analysis, the only independent predictor of poor outcome (mRS 3-6) was pre-treatment NIHSS score (p<0.001). CONCLUSION Patients with a HMCAS receiving IV rtPA did not fare worse at three months despite a greater proportion of patients with more severe strokes. Based on the current knowledge, IV rtPA remains a good treatment for patients with a HMCAS within three hours of symptom onset.
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Bugnicourt JM, Bonnaire B, Lepage L, Garcia PY, Lefranc M, Godefroy O. Infarctus cérébral par embolie calcaire spontanée révélant un rétrécissement aortique calcifié. ACTA ACUST UNITED AC 2008; 33:106-9. [DOI: 10.1016/j.jmv.2008.02.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2008] [Accepted: 02/21/2008] [Indexed: 11/27/2022]
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Tambasco N, Scaroni R, Corea F, Silvestrelli G, Rossi A, Bocola V, Parnetti L. Multimodal use of computed tomography in early acute stroke, part 1. Clin Exp Hypertens 2006; 28:421-6. [PMID: 16833055 DOI: 10.1080/10641960600549918] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Brain Computed tomography (CT) scan has been used in the past to exclude a hemorrhagic stroke, to determine a possible cause of the stroke patient symptoms, and to demonstrate a stabilized area of hypoperfusional flow. Several results from CT scan studies suggested that we could have new information on prognosis and outcome, localization, and risk of infarction. In this view, CT scan in acute stroke may contribute, using objective measures, to evaluate the inclusion in clinical and therapeutical trials, such as thrombolytic therapy. The lack of consensus among clinicians does not allow a secure and definitive system of CT scan evaluation. Besides its common uses, more recently brain CT scan provides new techniques utilizing advanced algorithms of reconstruction, with promising properties not yet completely verified, to highlight more aspects of acute stroke in the early phase. Despite this limitation, progress on neuroradiological techniques reinforces the concept that brain CT scan remains the key of studies, as well as of validation and routine treatment in terms of feasibility, low cost, and widely availability.
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Affiliation(s)
- Nicola Tambasco
- Dipartimento di Neurologia e Neuroriabilitazione, Villa Pini d'Abruzzo, Chieti, Italy.
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Lövblad KO, Baird AE. Actual diagnostic approach to the acute stroke patient. Eur Radiol 2005; 16:1253-69. [PMID: 16372164 DOI: 10.1007/s00330-005-0103-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2005] [Revised: 11/18/2005] [Accepted: 11/25/2005] [Indexed: 10/25/2022]
Abstract
Since acute stroke is now considered a potentially treatable medical emergency, a rapid and correct diagnosis must be made. The first step is to exclude hemorrhage, then to visualize any early ischemic changes, demonstrate the presence of hypoperfusion and locate the presence of a vascular underlying pathology as well as elucidate the presence of a potential penumbra (tissue at risk). Thanks to improvements and advances in both MR and CT technology, this can now be done in a number of ways. At the moment, CT is the most widely available and fast method for obtaining imaging of the brain and neck vessels of patients presenting with acute stroke. MRI can provide more precise information, although it remains slightly more time-consuming, but is, however, the method of choice for follow-up imaging. The main point is to take the one-stop-shopping approach where imaging of the vessels and brain is done from the aortic arch to the circle of Willis in one single session in order to have all the necessary information in the acute phase.
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Affiliation(s)
- Karl-Olof Lövblad
- Neuroradiology Unit, Radiology Department, SRRI, HUG Geneva University Hospital, 24 rue Micheli-du-Crest, 1211 Geneva 14, Switzerland.
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Abstract
The hyperdense artery sign on noncontrast head CT is thought to be one of the earliest and most useful signs of intra-arterial clot and probable (clinical) stroke. It should be evaluated in the context of the clinical scenario. Rigorous criteria should be applied in order to reduce potential false positives. The hyperdense middle cerebral artery sign is the most studied version and correlates with patient outcome. Our data suggest that the density on noncontrast head CT is not likely to universally represent in situ clot.
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Affiliation(s)
- Mark E Mullins
- Division of Neuroradiology, Massachusetts General Hospital, Boston 02114, USA.
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Demchuk AM, Coutts SB. Alberta Stroke Program Early CT Score in Acute Stroke Triage. Neuroimaging Clin N Am 2005; 15:409-19, xii. [PMID: 16198949 DOI: 10.1016/j.nic.2005.06.008] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
In the setting of acute stroke evaluation, CT is accessible, versatile, available, inexpensive, and, most importantly, fast. Its use extends beyond that of identifying intracranial hemorrhage. We have emphasized the importance of clinical assessment, supported by a systematic approach to unenhanced CT interpretation using the Alberta Stroke Program Early CT Score for determining the extent of early ischemic change. The use of CT bolus techniques (providing vascular CT angiography, CT angiography source images, and quantitative CT perfusion maps) can augment the clinical information obtained from unenhanced CT. CT is likely to remain the workhorse of acute stroke imaging for some time to come.
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Affiliation(s)
- Andrew M Demchuk
- Department of Clinical Neurosciences, Foothills Medical Centre, University of Calgary, Calgary, AB, Canada
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24
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Debruxelles S, Sibon I, Rouanet F, Orgogozo JM. Infarctus cérébral par embolie calcaire : complication spontanée révélatrice d’un rétrécissement aortique calcifié. Rev Neurol (Paris) 2004; 160:582-4. [PMID: 15269680 DOI: 10.1016/s0035-3787(04)70992-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Calcified aortic stenosis (CAS) is an unusual cause of cerebral infarct. The presence of cerebral intra-vascular or intra-parenchymatous calcifications, symptomatic or not, is suggestive of the diagnosis of CAS. We report two patients who experienced stroke induced by spontaneous calcic emboli from a calcified aortic valve and underline the importance of brain CT scan.
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Affiliation(s)
- S Debruxelles
- Fédération de Neurosciences Cliniques, CHU, Bordeaux
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25
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Donnan GA, Ma H, Mohr J. Overview of Laboratory Studies. Stroke 2004. [DOI: 10.1016/b0-44-306600-0/50022-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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26
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Gadda D. A case of bilateral dense middle cerebral arteries with CT angiographic confirmation of vascular occlusion. Emerg Radiol 2003; 10:142-3. [PMID: 15290502 DOI: 10.1007/s10140-003-0299-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2003] [Accepted: 07/03/2003] [Indexed: 11/30/2022]
Abstract
Hyperattenuating middle cerebral arteries on CT in acute stroke should generally not be associated with presence of intraluminal clot when bilaterally seen. We report a case of a woman who underwent emergency CT 60 min after sudden onset of coma. Bilateral dense middle cerebral arteries without parenchymal hypoattenuating areas or indirect signs of cerebral edema were present. CT angiography confirmed occlusion of the right middle cerebral artery and left internal carotid artery and middle cerebral artery.
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Affiliation(s)
- Davide Gadda
- Department of Radiology, Pistoia General Hospital, Pistoia, Italy.
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Tambasco N, Corea F, Luccioli R, Ciorba E, Parnetti L, Gallai V. Brain CT scan in acute ischemic stroke: early signs and functional outcome. Clin Exp Hypertens 2002; 24:687-96. [PMID: 12450244 DOI: 10.1081/ceh-120015345] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
There is evidence that an improvement of the diagnostic abilities could have a value for prognosis and therapy of the ischemic stroke. New neuroradiological strategies could be used with an amelioration of the evaluation and standardization of the ischemic damage. The value of early vascular sign remains controversial as a predictor of patient outcome. Early parenchymal changes are related to a poor outcome. The risk of hemorrhagic transformation increases with trombolytic therapy and especially with the onset of therapy. Between hemorrhagic transformation, only the large hematomas seems to be related to early deterioration and death. Brain Computed Tomography (CT) examination can give information about prognosis and therapeutic choice.
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Affiliation(s)
- Nicola Tambasco
- Dipartimento di Neuroscienze, Università di Perugia, Perugia, Italy.
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28
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Abstract
The rapid neuroimaging of a patient that has suffered a stroke is a critical preamble to the emergent initiation of thrombolytic therapy. Emergency physicians must be familiar with normal brain structures as they appear on CT, as well as common stroke patterns. The more facile emergency physicians are at interpreting the head CT, the better they can communicate with consulting specialists and deliver prompt care to patients that present with neurologic emergencies.
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Affiliation(s)
- David Sarkarati
- Michigan State University, Emergency Medicine Residency-Lansing, P.O. Box 30480, Lansing, MI 48909, USA
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29
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Somford DM, Nederkoorn PJ, Rutgers DR, Kappelle LJ, Mali WPTM, van der Grond J. Proximal and distal hyperattenuating middle cerebral artery signs at CT: different prognostic implications. Radiology 2002; 223:667-71. [PMID: 12034933 DOI: 10.1148/radiol.2233011017] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To determine whether a proximal (M1-segment) or distal (M2- and/or M3-segment) hyperattenuating middle cerebral artery (MCA) sign in patients with ischemic infarction in the territory of the MCA indicates a worse short-term prognosis than that in patients without a hyperattenuating MCA sign. MATERIALS AND METHODS We retrospectively reviewed the records of 352 patients who were diagnosed with ischemic brain infarction in the territory of the MCA. Of these patients, 186 patients met our final criteria and were included in this study. Nonenhanced computed tomography (CT) was performed for the entire brain, with a 5-mm section thickness in all patients, within 24 hours after symptom onset. The presence and location of a hyperattenuating MCA sign was correlated with neurologic deficit at discharge from the hospital (ie, short-term prognosis) by using the chi(2) test to detect differences between patient groups. RESULTS Patients with a hyperattenuating MCA sign at CT have a worse short-term prognosis than do patients without a hyperattenuating MCA sign (P <.05). Patients with a proximal hyperattenuating MCA sign have a significantly (P <.01) worse short-term prognosis than do patients with a distal hyperattenuating MCA sign. CONCLUSION A proximal hyperattenuating MCA sign is a reliable predictor of poor short-term prognosis in patients who experience acute stroke.
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Affiliation(s)
- Diederik M Somford
- Department of Radiology, University Medical Center Utrecht, E01.132, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands
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30
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Rutgers DR, van der Grond J, Jansen GH, Somford DM, Mali WPTM. Radiologic-pathologic correlation of the hyperdense middle cerebral artery sign. . A case report. Acta Radiol 2001. [DOI: 10.1034/j.1600-0455.2001.420506.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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31
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Kadimi S, Terry JB, Gomez CR. Hyperechoic middle cerebral artery: acute occlusion detected by transcranial duplex ultrasonography. J Neuroimaging 2000; 10:228-30. [PMID: 11147404 DOI: 10.1111/jon2000104228] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
The authors describe the appearance of acute thromboembolic occlusion of the middle cerebral artery (MCA) using transcranial duplex ultrasonography. Acute occlusion of the MCA commonly leads to severe cerebral infarction. In patients with acute MCA occlusion, secondary edema and elevated intracranial pressure are major causes of increased morbidity and mortality. Thus, the prompt detection of occlusion influences early therapy, including thrombolysis and increased control of intracranial pressure. The hyperdense appearance of the acutely occluded MCA as seen using computed tomography (CT) has been extensively reported in the literature. However, its appearance using transcranial duplex ultrasonography has not been reported. The authors report four patients who had clinical features of ischemia throughout the MCA territory. All patients were studied with CT and transcranial duplex ultrasonography within 6 hours of the onset of symptoms. Head CT of all four patients showed a hyperdense MCA sign with infarction of the MCA territory. Transcranial duplex studies using either pulsed Doppler or color Doppler sonography displayed a hyperechoic MCA with no evidence of flow. Subsequent duplex ultrasonography and magnetic resonance angiography showed all four patients had ipsilateral occlusion of the internal carotid artery. Transcranial duplex ultrasonography assists in the early diagnosis of acute MCA occlusion. The affected vessel is displayed as a hyperechoic structure associated with no flow using Doppler examination.
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MESH Headings
- Adult
- Aged
- Arterial Occlusive Diseases/diagnostic imaging
- Carotid Artery Diseases/diagnostic imaging
- Carotid Artery, Internal/diagnostic imaging
- Cerebrovascular Circulation/physiology
- Female
- Humans
- Image Enhancement
- Infarction, Middle Cerebral Artery/diagnostic imaging
- Magnetic Resonance Angiography
- Male
- Middle Aged
- Middle Cerebral Artery/diagnostic imaging
- Tomography, X-Ray Computed
- Ultrasonography, Doppler, Color
- Ultrasonography, Doppler, Duplex
- Ultrasonography, Doppler, Pulsed
- Ultrasonography, Doppler, Transcranial
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Affiliation(s)
- S Kadimi
- Comprehensive Stroke Center, University of Alabama, Birmingham, Alabama, USA
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32
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Abstract
Recent literature has identified many of the important factors helpful in predicting outcome even at the very acute stage of stroke. Demographic factors, risk factors, clinical exam findings, clinical scales laboratory tests, and neuroimaging all provide important information that can assist the clinician in predicting outcome. Specific factors seem to influence the effect of stroke treatments such as thrombolysis. Consideration of these factors is important when treatment decisions such as thrombolysis are being contemplated. New techniques such as eco-planar MR Imaging are now being developed that seem extremely accurate in predicting outcome. These techniques represent the "crystal ball" of predicting stroke outcome.
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Affiliation(s)
- A M Demchuk
- Department of Clinical Neurosciences, University of Calgary, Alberta, Canada
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33
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Abstract
Acute basilar artery occlusion is usually associated with a poor prognosis despite therapy with antiplatelet and anticoagulant agents. The natural history of this disorder should be fully understood before clinicians make decisions on therapy. Recent advances in angiography technique and the use of newer mobile microcatheters have made intra-arterial thrombolysis therapy feasible. There have been several small, uncontrolled series of intra-arterial thrombolysis in basilar artery occlusion with promising results.
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Affiliation(s)
- T G Phan
- Department of Neurology, Mayo Clinic, Rochester, Minnesota, USA
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34
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Marsman JW, Feenstra-Holtkamp M. Dense middle cerebral artery computed tomography sign: confirmation by magnetic resonance (MR) imaging and MR angiography. AUSTRALASIAN RADIOLOGY 1996; 40:257-60. [PMID: 8826730 DOI: 10.1111/j.1440-1673.1996.tb00398.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
In acute ischaemic stroke, the dense middle cerebral artery sign on computed tomography indicates occlusion of the middle cerebral artery. A case is described in which the sign was confirmed by magnetic resonance (MR) imaging and MR angiography.
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Affiliation(s)
- J W Marsman
- Department of Radiology, Gooi-Noord Hospital, Blaricum, The Netherlands
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35
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Shuaib IL, Crotch-Harvey MA. Dense artery sign of the middle cerebral artery: traumatic cause. AUSTRALASIAN RADIOLOGY 1995; 39:93-4. [PMID: 7695541 DOI: 10.1111/j.1440-1673.1995.tb00244.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Dense artery sign of the middle cerebral artery on non-enhanced computed tomography is recognized as an early sign of ensuing major cerebral infarction and is usually a consequence of thrombosis or embolism of an ischaemic stroke. A case is described resulting from trauma that correlated with angiographic and Doppler ultrasound findings and the significance of this sign in this case is discussed.
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Affiliation(s)
- I L Shuaib
- Department of Radiology, Arrowe Park Hospital, Liverpool, United Kingdom
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36
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Becker G, Lindner A, Hofmann E, Bogdahn U. Contribution of transcranial color-coded real-time sonography to the etiopathogenetic classification of middle cerebral artery stenosis. JOURNAL OF CLINICAL ULTRASOUND : JCU 1994; 22:471-477. [PMID: 7814651 DOI: 10.1002/jcu.1870220803] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Transcranial color-coded real-time sonography (TCCS) and cranial computed tomography were applied to patients with middle cerebral artery (MCA) stenosis to evaluate whether these techniques may disclose additional aspects of the pathophysiology of the stenotic lesion. In 15 patients with MCA stenosis identified by transcranial Doppler sonography, the echogenicity of the stenotic segment was estimated subjectively by TCCS. The density of the stenotic segment, prior to being detected by TCCS, was quantified by computed tomography. In 5 of the 15 patients, transcranial image-directed Doppler sonography identified a hyperechogenic lesion in association with the stenotic vascular segment; computed tomography demonstrated a "dense" artery (Hounsfield units [HU] > 120) in the corresponding vascular segment. In 10 patients the echogenicity of the stenotic segment was found to be normal, with a computed tomography density of < 100 HU in the corresponding segment. Hyperechogenic and hyperdense stenotic vascular segments in TCCS and computed tomography, respectively, may indicate an arteriosclerotic vascular lesion with calcium deposits. Normal echogenicity and normal to slightly elevated computed tomography-density of a stenotic vascular segment may suggest the presence of a thrombotic/embolic lesion.
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Affiliation(s)
- G Becker
- Department of Neurology, Neurologische Universitätsklinik Würzburg, Germany
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37
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Castillo M, Falcone S, Naidich TP, Bowen B, Quencer RM. Imaging in acute basilar artery thrombosis. Neuroradiology 1994; 36:426-9. [PMID: 7991083 DOI: 10.1007/bf00593675] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The aim of this study was to review the imaging features in acute (< 24 h) basilar artery thrombosis. CT and MR studies in 11 patients with clinical diagnosis of acute basilar artery thrombosis were retrospectively reviewed. MR angiography was obtained in 4 patients. Correlation with clinical symptoms was performed. Multiple cranial nerve palsies and hemiparesis were the most common clinical symptoms at presentation. CT revealed hyperdense basilar arteries (n = 7) and hypodensities in the posterior circulation territory (n = 8). In one instance, the infarction was hemorrhagic. MR imaging showed absence of flow void within the basilar in 6 patients and MRA (using both PC and TOF techniques) confirmed absence of blood flow in 4 basilar arteries. One week after presentation, 5 patients died. Autopsy was obtained in 1 case and confirmed the diagnosis of basilar artery thrombosis. Basilar artery thrombosis has fairly typical imaging features by both CT and MR. MRA may be used to confirm the diagnosis. Prompt recognition may lead to early thrombolytic treatment and may improve survival.
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Affiliation(s)
- M Castillo
- Department of Radiology, University of North Carolina School of Medicine, Chapel Hill
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38
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Harrington T, Roche J. The dense basilar artery as a sign of basilar territory infarction. AUSTRALASIAN RADIOLOGY 1993; 37:375-8. [PMID: 8257340 DOI: 10.1111/j.1440-1673.1993.tb00100.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Three cases of basilar artery territory infarction, in which a dense basilar artery was noted, are described. The dense basilar artery was recognized on computed tomography (CT) by comparing its density with that of other unaffected intracranial vessels. This sign is thought to represent basilar thrombosis or embolism and has similarities to the dense middle cerebral artery sign. The dense basilar artery is an early sign suggesting basilar territory infarction and its use improves the CT detection of basilar territory infarction.
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Affiliation(s)
- T Harrington
- Department of Diagnostic Radiology, Royal North Shore Hospital, St Leonards, NSW, Australia
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39
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Bradley WG, Yuh WT, Bydder GM. Use of MR imaging contrast agents in the brain. J Magn Reson Imaging 1993; 3:199-218. [PMID: 8428088 DOI: 10.1002/jmri.1880030133] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Affiliation(s)
- W G Bradley
- Memorial MR Center, Long Beach Memorial Medical Center, CA 90806
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