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de Vries L, van Herten RLM, Hoving JW, Išgum I, Emmer BJ, Majoie CBLM, Marquering HA, Gavves E. Spatio-temporal physics-informed learning: A novel approach to CT perfusion analysis in acute ischemic stroke. Med Image Anal 2023; 90:102971. [PMID: 37778103 DOI: 10.1016/j.media.2023.102971] [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: 03/16/2023] [Revised: 07/20/2023] [Accepted: 09/11/2023] [Indexed: 10/03/2023]
Abstract
CT perfusion imaging is important in the imaging workup of acute ischemic stroke for evaluating affected cerebral tissue. CT perfusion analysis software produces cerebral perfusion maps from commonly noisy spatio-temporal CT perfusion data. High levels of noise can influence the results of CT perfusion analysis, necessitating software tuning. This work proposes a novel approach for CT perfusion analysis that uses physics-informed learning, an optimization framework that is robust to noise. In particular, we propose SPPINN: Spatio-temporal Perfusion Physics-Informed Neural Network and research spatio-temporal physics-informed learning. SPPINN learns implicit neural representations of contrast attenuation in CT perfusion scans using the spatio-temporal coordinates of the data and employs these representations to estimate a continuous representation of the cerebral perfusion parameters. We validate the approach on simulated data to quantify perfusion parameter estimation performance. Furthermore, we apply the method to in-house patient data and the public Ischemic Stroke Lesion Segmentation 2018 benchmark data to assess the correspondence between the perfusion maps and reference standard infarct core segmentations. Our method achieves accurate perfusion parameter estimates even with high noise levels and differentiates healthy tissue from infarcted tissue. Moreover, SPPINN perfusion maps accurately correspond with reference standard infarct core segmentations. Hence, we show that using spatio-temporal physics-informed learning for cerebral perfusion estimation is accurate, even in noisy CT perfusion data. The code for this work is available at https://github.com/lucasdevries/SPPINN.
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Affiliation(s)
- Lucas de Vries
- Amsterdam UMC location University of Amsterdam, Biomedical Engineering and Physics, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands; Amsterdam UMC location University of Amsterdam, Radiology and Nuclear Medicine, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands; Informatics Institute, University of Amsterdam, Amsterdam, The Netherlands; Amsterdam Cardiovascular Sciences, Amsterdam, The Netherlands; Amsterdam Neuroscience, Amsterdam, The Netherlands.
| | - Rudolf L M van Herten
- Amsterdam UMC location University of Amsterdam, Biomedical Engineering and Physics, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands; Informatics Institute, University of Amsterdam, Amsterdam, The Netherlands; Amsterdam Cardiovascular Sciences, Amsterdam, The Netherlands
| | - Jan W Hoving
- Amsterdam UMC location University of Amsterdam, Radiology and Nuclear Medicine, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands; Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Ivana Išgum
- Amsterdam UMC location University of Amsterdam, Biomedical Engineering and Physics, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands; Amsterdam UMC location University of Amsterdam, Radiology and Nuclear Medicine, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands; Informatics Institute, University of Amsterdam, Amsterdam, The Netherlands; Amsterdam Cardiovascular Sciences, Amsterdam, The Netherlands; Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Bart J Emmer
- Amsterdam UMC location University of Amsterdam, Radiology and Nuclear Medicine, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands; Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Charles B L M Majoie
- Amsterdam UMC location University of Amsterdam, Radiology and Nuclear Medicine, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands; Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Henk A Marquering
- Amsterdam UMC location University of Amsterdam, Biomedical Engineering and Physics, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands; Amsterdam UMC location University of Amsterdam, Radiology and Nuclear Medicine, Meibergdreef 9, Amsterdam, 1105 AZ, The Netherlands; Amsterdam Cardiovascular Sciences, Amsterdam, The Netherlands; Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Efstratios Gavves
- Informatics Institute, University of Amsterdam, Amsterdam, The Netherlands
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2
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Gaulton TG, Martin K, Xin Y, Victor M, Ribeiro De Santis Santiago R, Britto Passos Amato M, Berra L, Cereda M. Regional lung perfusion using different indicators in electrical impedance tomography. J Appl Physiol (1985) 2023; 135:500-507. [PMID: 37439236 PMCID: PMC10538981 DOI: 10.1152/japplphysiol.00130.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 06/19/2023] [Accepted: 07/06/2023] [Indexed: 07/14/2023] Open
Abstract
Management of acute respiratory distress syndrome (ARDS) is classically guided by protecting the injured lung and mitigating damage from mechanical ventilation. Yet the natural history of ARDS is also dictated by disruption in lung perfusion. Unfortunately, diagnosis and treatment are hampered by the lack of bedside perfusion monitoring. Electrical impedance tomography is a portable imaging technique that can estimate regional lung perfusion in experimental settings from the kinetic analysis of a bolus of an indicator with high conductivity. Hypertonic sodium chloride has been the standard indicator. However, hypertonic sodium chloride is often inaccessible in the hospital, limiting practical adoption. We investigated whether regional lung perfusion measured using electrical impedance tomography is comparable between indicators. Using a swine lung injury model, we determined regional lung perfusion (% of total perfusion) in five pigs, comparing 12% sodium chloride to 8.4% sodium bicarbonate across stages of lung injury and experimental conditions (body position, positive end-expiratory pressure). Regional lung perfusion for four lung regions was determined from maximum slope analysis of the indicator-based impedance signal. Estimates of regional lung perfusion between indicators were compared in the lung overall and within four lung regions. Regional lung perfusion estimated with a sodium bicarbonate indicator agreed with a hypertonic sodium chloride indicator overall (mean bias 0%, limits of agreement -8.43%, 8.43%) and within lung quadrants. The difference in regional lung perfusion between indicators did not change across experimental conditions. Sodium bicarbonate may be a comparable indicator to estimate regional lung perfusion using electrical impedance tomography.NEW & NOTEWORTHY Electrical impedance tomography is an emerging tool to measure regional lung perfusion using kinetic analysis of a conductive indicator. Hypertonic sodium chloride is the standard agent used. We measured regional lung perfusion using another indicator, comparing hypertonic sodium chloride to sodium bicarbonate in an experimental swine lung injury model. We found strong agreement between the two indicators. Sodium bicarbonate may be a comparable indicator to measure regional lung perfusion with electrical impedance tomography.
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Affiliation(s)
- Timothy G Gaulton
- Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Kevin Martin
- Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Yi Xin
- Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Marcus Victor
- Pulmonary Division, Heart Institute (InCor), University of São Paulo, São Paulo, Brazil
- Medical Electrical Devices Laboratory (LabMed), Electronics Engineering, Aeronautics Institute of Technology, Sao Jose dos Campos, Brazil
| | - Roberta Ribeiro De Santis Santiago
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States
| | | | - Lorenzo Berra
- Department of Anesthesia, Critical Care, and Pain Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, United States
| | - Maurizio Cereda
- Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, Pennsylvania, United States
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3
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Mubarak F, Fatima H, Mustafa MS, Shafique MA, Abbas SR, Rangwala HS. Assessment Precision of CT Perfusion Imaging in the Detection of Acute Ischemic Stroke: A Systematic Review and Meta-Analysis. Cureus 2023; 15:e44396. [PMID: 37791142 PMCID: PMC10542215 DOI: 10.7759/cureus.44396] [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] [Accepted: 08/30/2023] [Indexed: 10/05/2023] Open
Abstract
Stroke, a prevalent medical emergency, comprises ischemic and hemorrhagic subtypes, with acute ischemic stroke (AIS) being a predominant type. The application of computed tomography perfusion (CTP) imaging has gained prominence due to its rapidity and accessibility in stroke evaluation. This study systematically reviews and conducts a meta-analysis of existing literature to assess the diagnostic accuracy of CTP in detecting AIS and predicting hemorrhagic transformation (HT). Employing Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, an extensive search was conducted across electronic databases and relevant radiology journals. Studies conducted between 2007 and 2023 that fulfilled predetermined inclusion criteria underwent quality assessment using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS 2) tool. Cochrane diagnostic accuracy tools were used for data extraction. Thirteen studies involving a total of 1014 patients were included in the analysis. The diagnostic performance of CTP in predicting HT demonstrated high sensitivity (86.7%) and moderate specificity (77.8%), resulting in an overall accuracy of 79.1%. The negative predictive value (NPV) was notably high (92.9%), signifying its efficacy in excluding patients at risk of HT. The positive predictive value (PPV) was comparatively lower (60.3%), highlighting the need for clinical context when making thrombolysis decisions. The false positive rate was 16.2%, while the false negative rate was minimal (9.8%). Subgroup analysis underscored consistent sensitivity and specificity across diverse imaging metrics. The findings of this study emphasize the promising diagnostic accuracy of CTP imaging in predicting HT subsequent to AIS. This non-invasive technique can aid treatment decisions and patient management strategies. By effectively assessing perfusion status and offering predictive insights, CTP imaging improves stroke intervention choices, especially in identifying patients with a lower risk of HT.
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Affiliation(s)
- Fatima Mubarak
- Department of Radiology, Aga Khan University Hospital, Karachi, PAK
| | - Hareer Fatima
- Department of Medicine, Jinnah Sindh Medical University, Karachi, PAK
| | | | | | - Syed Raza Abbas
- Department of Medicine, Dow University of Health Sciences, Karachi, PAK
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Xin Y, Kim T, Winkler T, Brix G, Gaulton T, Gerard SE, Herrmann J, Martin KT, Victor M, Reutlinger K, Amato M, Berra L, Kalra MK, Cereda M. Improving pulmonary perfusion assessment by dynamic contrast-enhanced computed tomography in an experimental lung injury model. J Appl Physiol (1985) 2023; 134:1496-1507. [PMID: 37167261 PMCID: PMC10228674 DOI: 10.1152/japplphysiol.00159.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 04/24/2023] [Accepted: 05/11/2023] [Indexed: 05/13/2023] Open
Abstract
Pulmonary perfusion has been poorly characterized in acute respiratory distress syndrome (ARDS). Optimizing protocols to measure pulmonary blood flow (PBF) via dynamic contrast-enhanced (DCE) computed tomography (CT) could improve understanding of how ARDS alters pulmonary perfusion. In this study, comparative evaluations of injection protocols and tracer-kinetic analysis models were performed based on DCE-CT data measured in ventilated pigs with and without lung injury. Ten Yorkshire pigs (five with lung injury, five healthy) were anesthetized, intubated, and mechanically ventilated; lung injury was induced by bronchial hydrochloric acid instillation. Each DCE-CT scan was obtained during a 30-s end-expiratory breath-hold. Reproducibility of PBF measurements was evaluated in three pigs. In eight pigs, undiluted and diluted Isovue-370 were separately injected to evaluate the effect of contrast viscosity on estimated PBF values. PBF was estimated with the peak-enhancement and the steepest-slope approach. Total-lung PBF was estimated in two healthy pigs to compare with cardiac output measured invasively by thermodilution in the pulmonary artery. Repeated measurements in the same animals yielded a good reproducibility of computed PBF maps. Injecting diluted isovue-370 resulted in smaller contrast-time curves in the pulmonary artery (P < 0.01) and vein (P < 0.01) without substantially diminishing peak signal intensity (P = 0.46 in the pulmonary artery) compared with the pure contrast agent since its viscosity is closer to that of blood. As compared with the peak-enhancement model, PBF values estimated by the steepest-slope model with diluted contrast were much closer to the cardiac output (R2 = 0.82) as compared with the peak-enhancement model. DCE-CT using the steepest-slope model and diluted contrast agent provided reliable quantitative estimates of PBF.NEW & NOTEWORTHY Dynamic contrast-enhanced CT using a lower-viscosity contrast agent in combination with tracer-kinetic analysis by the steepest-slope model improves pulmonary blood flow measurements and assessment of regional distributions of lung perfusion.
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Affiliation(s)
- Yi Xin
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts, United States
- Department of Anesthesia, Critical Care and Pain Medicine, Harvard Medical School, Boston, Massachusetts, United States
| | - Taehwan Kim
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts, United States
| | - Tilo Winkler
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts, United States
- Department of Anesthesia, Critical Care and Pain Medicine, Harvard Medical School, Boston, Massachusetts, United States
| | - Gunnar Brix
- Department of Medical and Occupational Radiation Protection, Federal Office for Radiation Protection, Salzgitter, Germany
| | - Timothy Gaulton
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts, United States
- Department of Anesthesia, Critical Care and Pain Medicine, Harvard Medical School, Boston, Massachusetts, United States
| | - Sarah E Gerard
- Roy J. Carver Department of Biomedical Engineering, University of Iowa, Iowa City, Iowa, United States
| | - Jacob Herrmann
- Roy J. Carver Department of Biomedical Engineering, University of Iowa, Iowa City, Iowa, United States
| | - Kevin T Martin
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts, United States
| | - Marcus Victor
- Disciplina de Pneumologia, Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
- Electronics Engineering Division, Aeronautics Institute of Technology, Sao Paulo, Brazil
| | - Kristan Reutlinger
- Department of Anesthesiology and Critical Care, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Marcelo Amato
- Disciplina de Pneumologia, Instituto do Coração, Hospital das Clínicas, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
| | - Lorenzo Berra
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts, United States
- Department of Anesthesia, Critical Care and Pain Medicine, Harvard Medical School, Boston, Massachusetts, United States
| | - Mannudeep K Kalra
- Department of Radiology, Massachusetts General Hospital, Boston, Massachusetts, United States
- Department of Radiology, Harvard Medical School, Boston, Massachusetts, United States
| | - Maurizio Cereda
- Department of Anesthesia, Critical Care and Pain Medicine, Massachusetts General Hospital, Boston, Massachusetts, United States
- Department of Anesthesia, Critical Care and Pain Medicine, Harvard Medical School, Boston, Massachusetts, United States
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One-stop patient-specific myocardial blood flow quantification technique based on allometric scaling law. J Biomech 2023; 151:111513. [PMID: 36868983 DOI: 10.1016/j.jbiomech.2023.111513] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 01/23/2023] [Accepted: 02/17/2023] [Indexed: 02/21/2023]
Abstract
Establishing a patient-specific and non-invasive technique to derive blood flow as well as coronary structural information from one single cardiac CT imaging modality. 336 patients with chest pain or ST segment depression on electrocardiogram were retrospectively enrolled. All patients underwent adenosine-stressed dynamic CT myocardial perfusion imaging (CT-MPI) and coronary computed tomography angiography (CCTA) in sequence. Relationship between myocardial mass (M) and blood flow (Q), defined as log(Q) = b · log(M) + log(Q0), was explored based on the general allometric scaling law. We used 267 patients to obtain the regression results and found strong linear relationship between M (gram) and Q (mL/min) (b = 0.786, log(Q0) = 0.546, r = 0.704; p < 0.001). We Also found this correlation was applicable for patients with either normal or abnormal myocardial perfusion (p < 0.001). Datasets from the other 69 patients were used to validate this M-Q correlation and found the patient-specific blood flow could be accurately estimated from CCTA compared to that measured from CT-MPI (146.480 ± 39.607 vs 137.967 ± 36.227, r = 0.816, and 146.480 ± 39.607 vs 137.967 ± 36.227, r = 0.817, for the left ventricle region and LAD-subtended region, respectively, all unit in mL/min). In conclusion, we established a technique to provide general and patient-specific myocardial mass-blood flow correlation obeyed to allometric scaling law. Blood flow information could be directly derived from structural information acquired from CCTA.
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Luijten SPR, Bos D, van Doormaal PJ, Goyal M, Dijkhuizen RM, Dippel DWJ, Roozenbeek B, van der Lugt A, Warnert EAH. Cerebral blood flow quantification with multi-delay arterial spin labeling in ischemic stroke and the association with early neurological outcome. Neuroimage Clin 2023; 37:103340. [PMID: 36739791 PMCID: PMC9932490 DOI: 10.1016/j.nicl.2023.103340] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 01/13/2023] [Accepted: 01/26/2023] [Indexed: 02/01/2023]
Abstract
Restoring blood flow to brain tissue at risk of infarction is essential for tissue survival and clinical outcome. We used cerebral blood flow (CBF) quantified with multiple post-labeling delay (PLD) pseudocontinuous arterial spin labeling (ASL) MRI after ischemic stroke and assessed the association between CBF and early neurological outcome. We acquired ASL with 7 PLDs at 3.0 T in large vessel occlusion stroke patients at 24 h. We quantified CBF relative to the contralateral hemisphere (rCBF) and defined hyperperfusion as a ≥30% increase and hypoperfusion as a ≥40% decrease in rCBF. We included 44 patients (median age: 70 years, median NIHSS: 13, 40 treated with endovascular thrombectomy) of whom 37 were recanalized. Hyperperfusion in ischemic core occurred in recanalized but not in non-recanalized patients (65.8% vs 0%, p = 0.006). Hypoperfusion occurred only in the latter group (0% vs 85.7%, p < 0.001). In recanalized patients, hyperperfusion was also seen in salvaged penumbra (38.9%). Higher rCBF in ischemic core (aβ, -2.75 [95% CI: -4.11 to -1.40]) and salvaged penumbra (aβ, -5.62 [95% CI: -9.57 to -1.68]) was associated with lower NIHSS scores at 24 h. In conclusion, hyperperfusion frequently occurs in infarcted and salvaged brain tissue following successful recanalization and early neurological outcome is positively associated with the level of reperfusion.
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Affiliation(s)
- Sven P R Luijten
- Department of Radiology & Nuclear Medicine, Erasmus MC University Medical Center, the Netherlands.
| | - Daniel Bos
- Department of Radiology & Nuclear Medicine, Erasmus MC University Medical Center, the Netherlands
| | - Pieter-Jan van Doormaal
- Department of Radiology & Nuclear Medicine, Erasmus MC University Medical Center, the Netherlands
| | - Mayank Goyal
- Department of Radiology, Foothills Medical Center, University of Calgary, Canada
| | - Rick M Dijkhuizen
- Biomedical MR Imaging and Spectroscopy Group, Center for Image Sciences, University Medical Center Utrecht & Utrecht University, the Netherlands
| | - Diederik W J Dippel
- Department of Neurology, Erasmus MC University Medical Center, the Netherlands
| | - Bob Roozenbeek
- Department of Neurology, Erasmus MC University Medical Center, the Netherlands
| | - Aad van der Lugt
- Department of Radiology & Nuclear Medicine, Erasmus MC University Medical Center, the Netherlands
| | - Esther A H Warnert
- Department of Radiology & Nuclear Medicine, Erasmus MC University Medical Center, the Netherlands
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7
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Value of CT Perfusion for Collateral Status Assessment in Patients with Acute Ischemic Stroke. Diagnostics (Basel) 2022; 12:diagnostics12123014. [PMID: 36553021 PMCID: PMC9777468 DOI: 10.3390/diagnostics12123014] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2022] [Revised: 11/24/2022] [Accepted: 11/27/2022] [Indexed: 12/04/2022] Open
Abstract
Good collateral status in acute ischemic stroke patients is an important indicator for good outcomes. Perfusion imaging potentially allows for the simultaneous assessment of local perfusion and collateral status. We combined multiple CTP parameters to evaluate a CTP-based collateral score. We included 85 patients with a baseline CTP and single-phase CTA images from the MR CLEAN Registry. We evaluated patients' CTP parameters, including relative CBVs and tissue volumes with several time-to-maximum ranges, to be candidates for a CTP-based collateral score. The score candidate with the strongest association with CTA-based collateral score and a 90-day mRS was included for further analyses. We assessed the association of the CTP-based collateral score with the functional outcome (mRS 0-2) by analyzing three regression models: baseline prognostic factors (model 1), model 1 including the CTA-based collateral score (model 2), and model 1 including the CTP-based collateral score (model 3). The model performance was evaluated using C-statistic. Among the CTP-based collateral score candidates, relative CBVs with a time-to-maximum of 6-10 s showed a significant association with CTA-based collateral scores (p = 0.02) and mRS (p = 0.05) and was therefore selected for further analysis. Model 3 most accurately predicted favorable outcomes (C-statistic = 0.86, 95% CI: 0.77-0.94) although differences between regression models were not statistically significant. We introduced a CTP-based collateral score, which is significantly associated with functional outcome and may serve as an alternative collateral measure in settings where MR imaging is not feasible.
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Deak Z, Schuettoff L, Lohse AK, Fabritius M, Reidler P, Forbrig R, Kunz W, Dimitriadis K, Ricke J, Sabel B. Reduction in Radiation Exposure of CT Perfusion by Optimized Imaging Timing Using Temporal Information of the Preceding CT Angiography of the Carotid Artery in the Stroke Protocol. Diagnostics (Basel) 2022; 12:diagnostics12112853. [PMID: 36428913 PMCID: PMC9689781 DOI: 10.3390/diagnostics12112853] [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: 09/25/2022] [Revised: 11/05/2022] [Accepted: 11/16/2022] [Indexed: 11/19/2022] Open
Abstract
(1) Background: CT perfusion (CTP) is a fast, robust and widely available but dose-exposing imaging technique for infarct core and penumbra detection. Carotid CT angiography (CTA) can precede CTP in the stroke protocol. Temporal information of the bolus tracking series of CTA could allow for better timing and a decreased number of scans in CTP, resulting in less radiation exposure, if the shortening of CTP does not alter the calculated infarct core and penumbra or the resulting perfusion maps, which are essential for further treatment decisions. (2) Methods: 66 consecutive patients with ischemic stroke proven by follow-up imaging or endovascular intervention were included in this retrospective study approved by the local ethics committee. In each case, six simulated, stepwise shortened CTP examinations were compared with the original data regarding the perfusion maps, infarct core, penumbra and endovascular treatment decision. (3) Results: In simulated CTPs with 26, 28 and 30 scans, the infarct core, penumbra and PRR values were equivalent, and the resulting clinical decision was identical to the original CTP. (4) Conclusions: The temporal information of the bolus tracking series of the carotid CTA can allow for better timing and a lower radiation exposure by eliminating unnecessary scans in CTP.
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Affiliation(s)
- Zsuzsanna Deak
- Imaging Urania, Laurenzerberg 2, 1010 Vienna, Austria
- Correspondence:
| | - Lara Schuettoff
- Department of Radiology, University Hospital of Munich (LMU), Marchioninistr. 15, 81377 Munich, Germany
| | - Ann-Kathrin Lohse
- Department of Radiology, University Hospital of Munich (LMU), Marchioninistr. 15, 81377 Munich, Germany
| | - Matthias Fabritius
- Department of Radiology, University Hospital of Munich (LMU), Marchioninistr. 15, 81377 Munich, Germany
| | - Paul Reidler
- Department of Radiology, University Hospital of Munich (LMU), Marchioninistr. 15, 81377 Munich, Germany
| | - Robert Forbrig
- Department of Neuroradiology, University Hospital of Munich (LMU), Marchioninistr. 15, 81377 Munich, Germany
| | - Wolfgang Kunz
- Department of Radiology, University Hospital of Munich (LMU), Marchioninistr. 15, 81377 Munich, Germany
| | - Konstantin Dimitriadis
- Department of Neurology, University Hospital of Munich (LMU), Marchioninistr. 15, 81377 Munich, Germany
| | - Jens Ricke
- Department of Radiology, University Hospital of Munich (LMU), Marchioninistr. 15, 81377 Munich, Germany
| | - Bastian Sabel
- Department of Radiology, University Hospital of Munich (LMU), Marchioninistr. 15, 81377 Munich, Germany
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9
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Lee D, Kim ES, Lee Y, Lee SM, Yoon DY, Ju YS, Chang IB. Changes in computed tomography perfusion parameters and maximum contrast enhancement in patients having hydrocephalus with a ventriculoperitoneal shunt: a pilot study. Acta Radiol 2022; 63:1398-1405. [PMID: 34781783 DOI: 10.1177/02841851211038807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
BACKGROUND Acute hydrocephalus may decrease cerebral perfusion by increasing intracranial pressure. Computed tomography perfusion (CTP) has become a significant adjunct in evaluating regional and global cerebral blood flow (CBF). PURPOSE To investigate the changes in cerebral perfusion parameters and maximum contrast enhancement (MCE) in patients with hydrocephalus with ventriculoperitoneal shunt (VPS). MATERIAL AND METHODS We performed brain CTP in 45 patients, including those with subarachnoid hemorrhage (SAH)-induced hydrocephalus with VPS (n = 14, G1), hydrocephalus (not related to SAH) with VPS (n = 11, G2), SAH-induced hydrocephalus without VPS (n = 10, G3), and hydrocephalus (not related to SAH) without VPS (n = 10, G4). We measured the cerebral perfusion in the frontal white matter (FWM), centrum semiovale, basal ganglia (BG), and eight cortical lesions of interest and compared the differences in CTP parameters among the groups. RESULTS Between the four groups, cerebral blood volume and MCE in the left FWM and CBF in the right FWM increased significantly in G1 and G2 who underwent VP shunt compared to G3 and G4, whereas perfusion significantly reduced in G3 and G4 who did not undergo VP shunt compared to G1 and G2. MCE in the left BG significantly increased in G2 and decreased in G3 and G4. SAH-induced hydrocephalus showed a lower perfusion than hydrocephalus (not related to SAH) in FWM. CONCLUSIONS Perfusion changes in patients with hydrocephalus after VP shunt were seen in the FWM and BG, which appears to be the result of the hydrocephalus reducing brain perfusion in the deep part of the brain. We concluded that SAH slows brain perfusion recovery.
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Affiliation(s)
- Dongjun Lee
- Department of Radiology, 158781Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Republic of Korea
| | - Eun Soo Kim
- Department of Radiology, 158781Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Republic of Korea
| | - Yul Lee
- Department of Radiology, 158781Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Republic of Korea
| | - Sang Min Lee
- Department of Radiology, 158781Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Republic of Korea
| | - Dae Young Yoon
- Department of Radiology, Kangdong Sacred Heart Hospital, 568730Hallym University College of Medicine, Gangdong-gu, Republic of Korea
| | - Young-Su Ju
- Department of Occupational & Environmental Medicine, National Medical Center, Seoul, Republic of Korea
| | - In-Bok Chang
- Department of Neurosurgery, 158781Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Republic of Korea
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Rigler I, Gspan T, Avsenik J, Milošević Z, Pretnar Oblak J. Independent Significance of Visual Assessment of Perfusion CT Maps in Anterior Circulation Stroke Patients Treated with Mechanical Thrombectomy. Clin Neuroradiol 2022; 32:829-837. [PMID: 35175361 DOI: 10.1007/s00062-022-01140-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Accepted: 01/17/2022] [Indexed: 12/30/2022]
Abstract
BACKGROUND In the absence of an automated software analysis, the role of computed tomography perfusion (CTP) in a real time clinical practice is not well established. We evaluated the clinical significance of a widely accessible and simple visual grading scale of CTP in the anterior circulation of acute ischemic stroke (AIS) patients treated with mechanical thrombectomy (MT). METHODS The single center consecutive CT investigations of AIS patients treated with MT in the anterior circulation have been evaluated retrospectively. ASPECT score and collateral circulation evaluation based on the Maas score were determined. Time to peak parametric maps, derived from CTP, were graded into four categories, from least to most favorable. The primary endpoint was functional outcome evaluated as modified Rankin Scale (mRS) ≤ 2 at 90 days after MT. RESULTS We included 318 patients in the analysis; 142 (45%) patients had mRS ≤ 2 after 90 days, mortality rate was 24%. Higher CTP and Maas score were significantly correlated with better clinical outcome (Pearson χ2 25.0 and 37.7, respectively; p < 0.01). Collateral circulation and CTP grades were strongly interrelated (Pearson χ2 78.6; p < 0.01). The CTP grade demonstrated statistically significant independent correlation with the clinical outcome irrespective of the collateral circulation grade, ASPECT score and age (OR 2.5; p = 0.011). The correlation was more pronounced in patients with normal collateral circulation (OR 3.27; p = 0.029). CONCLUSION We demonstrated that both visually graded CTP and collateral circulation grade strongly correlated with the clinical outcome of MT in the anterior circulation of AIS patients. Importantly, CTP correlated with the clinical outcome independent of the collateral circulation.
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Affiliation(s)
- Igor Rigler
- Department of Vascular Neurology, University Medical Centre Ljubljana, Zaloska 2, 1000, Ljubljana, Slovenia.
| | - Tina Gspan
- Neurology Department, University Medical Centre Ljubljana, Zaloska 2, 1000, Ljubljana, Slovenia
| | - Jernej Avsenik
- Clinical Institute of Radiology, University Medical Centre Ljubljana, Zaloska 2, 1000, Ljubljana, Slovenia
| | - Zoran Milošević
- Clinical Institute of Radiology, University Medical Centre Ljubljana, Zaloska 2, 1000, Ljubljana, Slovenia
| | - Janja Pretnar Oblak
- Department of Vascular Neurology, University Medical Centre Ljubljana, Zaloska 2, 1000, Ljubljana, Slovenia.,Neurology Department, Faculty of Medicine, University of Ljubljana, Vrazov trg 2, Ljubljana, Slovenia
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11
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Li J, Zhang Y, Yin D, Shang H, Li K, Jiao T, Fang C, Cui Y, Liu M, Pan J, Zeng Q. CT perfusion-based delta-radiomics models to identify collateral vessel formation after revascularization in patients with moyamoya disease. Front Neurosci 2022; 16:974096. [PMID: 36033623 PMCID: PMC9403315 DOI: 10.3389/fnins.2022.974096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2022] [Accepted: 07/20/2022] [Indexed: 11/15/2022] Open
Abstract
Purpose To build CT perfusion (CTP)-based delta-radiomics models to identify collateral vessel formation after revascularization in patients with moyamoya disease (MMD). Methods Fifty-three MMD patients who underwent CTP and digital subtraction angiography (DSA) examination were retrospectively enrolled. Patients were divided into good and poor groups based on postoperative DSA. CTP parameters, such as mean transit time (MTT), time to drain (TTD), time to maximal plasma concentration (Tmax), and flow extraction product (FE), were obtained. CTP efficacy in evaluating surgical treatment were compared between the good and poor groups. The changes in the relative CTP parameters (ΔrMTT, ΔrTTD, ΔrTmax, and ΔrFE) were calculated to evaluate the differences between pre- and postoperative CTP values. CTP parameters were selected to build delta-radiomics models for identifying collateral vessel formation. The identification performance of machine learning classifiers was assessed using area under the receiver operating characteristic curve (AUC). Results Of the 53 patients, 36 (67.9%) and 17 (32.1%) were divided into the good and poor groups, respectively. The postoperative changes of ΔrMTT, ΔrTTD, ΔrTmax, and ΔrFE in the good group were significantly better than the poor group (p < 0.05). Among all CTP parameters in the perfusion improvement evaluation, the ΔrTTD had the largest AUC (0.873). Eleven features were selected from the TTD parameter to build the delta-radiomics model. The classifiers of the support vector machine and k-nearest neighbors showed good diagnostic performance with AUC values of 0.933 and 0.867, respectively. Conclusion The TTD-based delta-radiomics model has the potential to identify collateral vessel formation after the operation.
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Affiliation(s)
- Jizhen Li
- Department of Radiology, Shandong Provincial Qianfoshan Hospital, Shandong University, Jinan, China
- Department of Radiology, Shandong Mental Health Center Affiliated to Shandong University, Jinan, China
| | - Yan Zhang
- Department of Radiology, Shandong Mental Health Center Affiliated to Shandong University, Jinan, China
| | - Di Yin
- Department of Radiology, Shandong Provincial Qianfoshan Hospital, Shandong University, Jinan, China
| | - Hui Shang
- Department of Radiology, The First Affiliated Hospital of Shandong First Medical University, Shandong Provincial Qianfoshan Hospital, Jinan, China
| | - Kejian Li
- Department of Radiology, The First Affiliated Hospital of Shandong First Medical University, Shandong Provincial Qianfoshan Hospital, Jinan, China
| | - Tianyu Jiao
- Department of Radiology, The First Affiliated Hospital of Shandong First Medical University, Shandong Provincial Qianfoshan Hospital, Jinan, China
| | - Caiyun Fang
- Department of Radiology, The First Affiliated Hospital of Shandong First Medical University, Shandong Provincial Qianfoshan Hospital, Jinan, China
| | - Yi Cui
- Department of Radiology, Qilu Hospital of Shandong University, Jinan, China
| | - Ming Liu
- Department of Neurosurgery, Qilu Hospital of Shandong University, Jinan, China
| | - Jun Pan
- Department of Radiology, Shandong Mental Health Center Affiliated to Shandong University, Jinan, China
| | - Qingshi Zeng
- Department of Radiology, Shandong Provincial Qianfoshan Hospital, Shandong University, Jinan, China
- Department of Radiology, The First Affiliated Hospital of Shandong First Medical University, Shandong Provincial Qianfoshan Hospital, Jinan, China
- *Correspondence: Qingshi Zeng,
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12
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Nicolas-Jilwan M, Wintermark M. Automated Brain Perfusion Imaging in Acute Ischemic Stroke: Interpretation Pearls and Pitfalls. Stroke 2021; 52:3728-3738. [PMID: 34565174 DOI: 10.1161/strokeaha.121.035049] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Recent advancements in computed tomography technology, including improved brain coverage and automated processing of the perfusion data, have reinforced the use of perfusion computed tomography imaging in the routine evaluation of patients with acute ischemic stroke. The DAWN (Diffusion Weighted Imaging or Computerized Tomography Perfusion Assessment With Clinical Mismatch in the Triage of Wake Up and Late Presenting Strokes Undergoing Neurointervention) and DEFUSE 3 (Endovascular Therapy Following Imaging Evaluation for Ischemic Stroke 3) trials have established the benefit of endovascular thrombectomy in patients with acute ischemic stroke with anterior circulation large vessel occlusion up to 24 hours of last seen normal, using perfusion imaging-based patient selection. The compelling data has prompted stroke centers to increasingly introduce automated perfusion computed tomography imaging in the routine evaluation of patients with acute ischemic stroke. We present a comprehensive overview of the acquisition and interpretation of automated perfusion imaging in patients with acute ischemic stroke with a special emphasis on the interpretation pearls, pitfalls, and stroke mimicking conditions.
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Affiliation(s)
- Manal Nicolas-Jilwan
- Division of Neuroradiology, Department of Radiology, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia (M.N.-J.)
| | - Max Wintermark
- Division of Neuroimaging and Neurointervention, Department of Radiology, Stanford Healthcare, CA (M.W.)
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13
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Potreck A, Seker F, Mutke MA, Weyland CS, Herweh C, Heiland S, Bendszus M, Möhlenbruch M. What is the impact of head movement on automated CT perfusion mismatch evaluation in acute ischemic stroke? J Neurointerv Surg 2021; 14:628-633. [PMID: 34301804 DOI: 10.1136/neurintsurg-2021-017510] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2021] [Accepted: 07/04/2021] [Indexed: 11/04/2022]
Abstract
OBJECTIVES Automated CT perfusion mismatch assessment is an established treatment decision tool in acute ischemic stroke. However, the reliability of this method in patients with head motion is unclear. We therefore sought to evaluate the influence of head movement on automated CT perfusion mismatch evaluation. METHODS Using a realistic CT brain-perfusion-phantom, 7 perfusion mismatch scenarios were simulated within the left middle cerebral artery territory. Real CT noise and artificial head movement were added. Thereafter, ischemic core, penumbra volumes and mismatch ratios were evaluated using an automated mismatch analysis software (RAPID, iSchemaView) and compared with ground truth simulated values. RESULTS While CT scanner noise alone had only a minor impact on mismatch evaluation, a tendency towards smaller infarct core estimates (mean difference of -5.3 (-14 to 3.5) mL for subtle head movement and -7.0 (-14.7 to 0.7) mL for strong head movement), larger penumbral estimates (+9.9 (-25 to 44) mL and +35 (-14 to 85) mL, respectively) and consequently larger mismatch ratios (+0.8 (-1.5 to 3.0) for subtle head movement and +1.9 (-1.3 to 5.1) for strong head movement) were noted in dependence of patient head movement. CONCLUSIONS Motion during CT perfusion acquisition influences automated mismatch evaluation. Potentially treatment-relevant changes in mismatch classifications in dependence of head movement were observed and occurred in favor of mechanical thrombectomy.
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Affiliation(s)
- Arne Potreck
- Department of Neuroradiology, University Hospital Heidelberg, Heidelberg, Germany
| | - Fatih Seker
- Department of Neuroradiology, University Hospital Heidelberg, Heidelberg, Germany
| | | | | | - Christian Herweh
- Department of Neuroradiology, University Hospital Heidelberg, Heidelberg, Germany
| | - Sabine Heiland
- Department of Neuroradiology, University Hospital Heidelberg, Heidelberg, Germany
| | - Martin Bendszus
- Department of Neuroradiology, University Hospital Heidelberg, Heidelberg, Germany
| | - Markus Möhlenbruch
- Department of Neuroradiology, University Hospital Heidelberg, Heidelberg, Germany
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14
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Karhi S, Tähtinen O, Aherto J, Matikka H, Manninen H, Nerg O, Taina M, Jäkälä P, Vanninen R. Effect of different thresholds for CT perfusion volumetric analysis on estimated ischemic core and penumbral volumes. PLoS One 2021; 16:e0249772. [PMID: 33882098 PMCID: PMC8059822 DOI: 10.1371/journal.pone.0249772] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 03/24/2021] [Indexed: 01/08/2023] Open
Abstract
Purpose This single-center study compared three threshold settings for automated analysis of the ischemic core (IC) and penumbral volumes using computed tomographic perfusion, and their accuracy for predicting final infarct volume (FIV) in patients with anterior circulation acute ischemic stroke (AIS). Methods Fifty-two consecutive AIS patients undergoing mechanical thrombectomy (November 2015–March 2018) were included. Perfusion images were retrospectively analyzed using a single CT Neuro perfusion application (syngo.via 4.1, Siemens Healthcare GmbH). Three threshold values (S1–S3) were derived from another commercial package (RAPID; iSchema View) (S1), up-to-date syngo.via default values (S2), and adapted values for syngo.via from a reference study (S3). The results were compared with FIV determined by non-contrast CT. Results The median IC volume (mL) was 24.6 (interquartile range: 13.7–58.1) with S1 and 30.1 (20.1–53.1) with S2/S3. After removing the contralateral hemisphere from the analysis, the median IC volume decreased by 1.33(0–3.14) with S1 versus 9.13 (6.24–14.82) with S2/S3. The median penumbral volume (mL) was 74.52 (49.64–131.91), 77.86 (46.56–99.23), and 173.23 (125.86–200.64) for S1, S2, and S3, respectively. Limiting analysis to the affected hemisphere, the penumbral volume decreased by 1.6 (0.13–9.02), 19.29 (12.59–26.52), and 58.33 mL (45.53–74.84) for S1, S2, and S3, respectively. The correlation between IC and FIV was highest in patients with successful recanalization (n = 34, r = 0.784 for S1; r = 0.797 for S2/S3). Conclusion Optimizing thresholds significantly improves the accuracy of estimated IC and penumbral volumes. Current recommended values produce diversified results. International guidelines based on larger multicenter studies should be established to support the standardization of volumetric analysis in clinical decision-making.
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Affiliation(s)
- Simo Karhi
- Department of Clinical Radiology, Kuopio University Hospital, Kuopio, Finland
- Unit of Radiology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland
- * E-mail:
| | - Olli Tähtinen
- Department of Clinical Radiology, Kuopio University Hospital, Kuopio, Finland
- Unit of Radiology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland
| | - Joona Aherto
- Department of Clinical Radiology, Kuopio University Hospital, Kuopio, Finland
- Unit of Radiology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland
| | - Hanna Matikka
- Department of Clinical Radiology, Kuopio University Hospital, Kuopio, Finland
| | - Hannu Manninen
- Department of Clinical Radiology, Kuopio University Hospital, Kuopio, Finland
- Unit of Radiology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland
| | - Ossi Nerg
- Unit of Neurology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland
- Neuro Center, Kuopio University Hospital, Kuopio, Finland
| | - Mikko Taina
- Department of Clinical Radiology, Kuopio University Hospital, Kuopio, Finland
- Unit of Radiology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland
| | - Pekka Jäkälä
- Unit of Neurology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland
- Neuro Center, Kuopio University Hospital, Kuopio, Finland
| | - Ritva Vanninen
- Department of Clinical Radiology, Kuopio University Hospital, Kuopio, Finland
- Unit of Radiology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland
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15
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van Ommen F, Bennink E, Dankbaar JW, Kauw F, de Jong HWAM. Improving the Quality of Cerebral Perfusion Maps With Monoenergetic Dual-Energy Computed Tomography Reconstructions. J Comput Assist Tomogr 2021; 45:103-109. [PMID: 32176156 DOI: 10.1097/rct.0000000000000981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE We compared 40- to 70-keV virtual monoenergetic to conventional computed tomography (CT) perfusion reconstructions with respect to quality of perfusion maps. METHODS Conventional CT perfusion (CTP) images were acquired at 80 kVp in 25 patients, and 40- to 70-keV images were acquired with a dual-layer CT at 120 kVp in 25 patients. First, time-attenuation-curve contrast-to-noise ratio was assessed. Second, the perfusion maps of both groups were qualitatively analyzed by observers. Last, the monoenergetic reconstruction with the highest quality was compared with the clinical standard 80-kVp CTP acquisitions. RESULTS Contrast-to-noise ratio was significantly better for 40 to 60 keV as compared with 70 keV and conventional images (P < 0.001). Visually, the difference between the blood volume maps among reconstructions was minimal. The 50-keV perfusion maps had the highest quality compared with the other monoenergetic and conventional maps (P < 0.002). CONCLUSIONS The quality of 50-keV CTP images is superior to the quality of conventional 80- and 120-kVp images.
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Affiliation(s)
| | | | | | - Frans Kauw
- From the Departments of Radiology and Nuclear Medicine
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16
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Krähling H, Masthoff M, Schwindt W, Stracke CP, Schindler P. Intraosseous contrast administration for emergency stroke CT. Neuroradiology 2021; 63:967-970. [PMID: 33462626 PMCID: PMC8128809 DOI: 10.1007/s00234-021-02642-w] [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: 11/30/2020] [Accepted: 01/07/2021] [Indexed: 05/30/2023]
Abstract
Computed tomography (CT) imaging in acute stroke is an established and fairly widespread approach, but there is no data on applicability of intraosseous (IO) contrast administration in the case of failed intravenous (IV) cannula placement. Here, we present the first case of IO contrast administration for CT imaging in suspected acute stroke providing a dedicated CT examination protocol and analysis of achieved image quality as well as a review of available literature.
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Affiliation(s)
- Hermann Krähling
- Clinic for Radiology, University Hospital Muenster, Muenster, Germany
| | - Max Masthoff
- Clinic for Radiology, University Hospital Muenster, Muenster, Germany
| | - Wolfram Schwindt
- Clinic for Radiology, University Hospital Muenster, Muenster, Germany.,Division of Interventional Neuroradiology, University Hospital Muenster, Muenster, Germany
| | - Christian Paul Stracke
- Clinic for Radiology, University Hospital Muenster, Muenster, Germany.,Division of Interventional Neuroradiology, University Hospital Muenster, Muenster, Germany
| | - Philipp Schindler
- Clinic for Radiology, University Hospital Muenster, Muenster, Germany.
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17
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Reidler P, Mueller F, Stueckelschweiger L, Feil K, Kellert L, Fabritius MP, Liebig T, Tiedt S, Puhr-Westerheide D, Kunz WG. Diaschisis revisited: quantitative evaluation of thalamic hypoperfusion in anterior circulation stroke. NEUROIMAGE-CLINICAL 2020; 27:102329. [PMID: 32629166 PMCID: PMC7334597 DOI: 10.1016/j.nicl.2020.102329] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Revised: 06/02/2020] [Accepted: 06/21/2020] [Indexed: 11/21/2022]
Abstract
CT perfusion reveals thalamic hypoperfusion in acute anterior circulation stroke. This indirect phenomenon is referred to as ipsilateral thalamic diaschisis (ITD). Quantitative analysis indicates that ITD is a non-binary phenomenon. ITD is associated with lesion extent and involvement of the lentiform nucleus. Stroke outcome was not associated with ITD parameters.
Purpose Ipsilateral thalamic diaschisis (ITD) refers to the phenomenon of thalamic hypoperfusion or hypometabolism due to a distant cerebral injury. To further investigate the characteristics and spectrum of ITD, we analyzed quantitative measurements of thalamic hypoperfusion in acute anterior circulation stroke. Methods We selected consecutive patients with large-vessel occlusion (LVO) anterior circulation stroke and available CT perfusion (CTP) examination on admission who underwent endovascular thrombectomy. Thalamic perfusion parameters on CTP were tested between ipsi- and contralesional thalamus and ischemic territory. Values were compared with thresholds from CTP analysis software. Associations of thalamic perfusion parameters with acute imaging and clinical data were determined in uni- and multivariate logistic regression analyses. Results Ninety-nine patients were included. All perfusion parameters indicated significant non-ischemic hypoperfusion of the thalamus, not reaching the levels of ischemia in the middle cerebral artery territory due to LVO (all p < 0.002). Multiple perfusion parameters exhibited significant association with ischemic lesion extent (relative cerebral blood flow [CBF]: β = − 0.23, p = 0.022; Δtime to drain: β = 0.33, p < 0.001; ΔTmax: β = − 0.36, p < 0.001) and involvement of the Lentiform Nucleus (Δmean transit time: β = 0.64, p = 0.04; Δtime to drain: β = 0.81, p = 0.01; ΔTmax: β = − 0.82, p = 0.01). Symptom severity on admission exhibited minor significant association with reduction of thalamic CBF in uncorrected analysis (Odds ratio: 0.05, p = 0.049), but short- and long-term outcomes were unaffected by perfusion status. ITD reached guideline-based software-threshold levels in only one patient. Conclusions ITD in acute stroke is a non-binary phenomenon affected by lesion extent and involvement of the lentiform nucleus. We found uncorrected association of ITD with early clinical presentation, but no association with short- or long-term outcome was evident. Relevant misclassification of ITD by guideline-based CTP software was not indicated, which needs further dedicated testing.
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Affiliation(s)
- Paul Reidler
- Department of Radiology, University Hospital, LMU Munich, Germany
| | | | | | - Katharina Feil
- Department of Neurology, University Hospital, LMU Munich, Germany
| | - Lars Kellert
- Department of Neurology, University Hospital, LMU Munich, Germany
| | | | - Thomas Liebig
- Department of Neuroradiology, University Hospital, LMU Munich, Germany
| | - Steffen Tiedt
- Institute for Stroke and Dementia Research, LMU Munich, Germany
| | | | - Wolfgang G Kunz
- Department of Radiology, University Hospital, LMU Munich, Germany.
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18
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Capaldi DPI, Hristov DH, Kidd EA. Parametric Response Mapping of Coregistered Positron Emission Tomography and Dynamic Contrast Enhanced Computed Tomography to Identify Radioresistant Subvolumes in Locally Advanced Cervical Cancer. Int J Radiat Oncol Biol Phys 2020; 107:756-765. [PMID: 32251757 DOI: 10.1016/j.ijrobp.2020.03.023] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2019] [Revised: 03/06/2020] [Accepted: 03/19/2020] [Indexed: 01/31/2023]
Abstract
PURPOSE To identify subvolumes that may predict treatment response to definitive concurrent chemoradiation therapy using parametric response mapping (PRM) of coregistered positron emission tomography (PET) and dynamic contrast-enhanced (DCE) computed tomography (CT) in locally advanced cervical carcinoma. METHODS AND MATERIALS Pre- and midtreatment (after 23 ± 4 days of concurrent chemoradiation therapy) DCE CT and PET imaging were performed on 21 patients with cervical cancer who were enrolled in a pilot study to evaluate the prognostic value of CT perfusion for primary cervical cancer (NCT01805141). Three-dimensional coregistered maps of PET/CT standardized uptake value (SUV) and DCE CT blood flow (BF) were generated. PRM was performed using voxel-wise joint histogram analysis to classify voxels within the tumor as highly metabolic and perfused (SUVhiBFhi), highly metabolic and hypoxic (SUVhiBFlo), low metabolic activity and hypoxic (SUVloBFlo), or low metabolic activity and perfused (SUVloBFhi) tissue based on thresholds determined from population means of pretreatment PET SUV and DCE CT BF. Relationships between baseline pretreatment imaging metrics and relative changes in metabolic tumor volume (ΔMTV), calculated from before treatment and during treatment imaging, were determined using univariable and multivariable linear regression models. RESULTS The relative volume of three PRM subvolumes significantly changed during treatment (SUVhiBFhi: P = .04; SUVhiBFlo: P = .0008; SUVloBFhi: P = .02), whereas SUVloBFlo did not (P = .9). Pretreatment PET SUVmax (r = -.58, P = .006), PET SUVmean (ρ = -.59, P = .005), DCE CT BFmean (r = -.50, P = .02), tumor volume (ρ = -.65, P = .001) and PRM SUVhiBFhi (ρ = -.59, P = .004) were negatively correlated with ΔMTV, whereas PRM SUVloBFlo was positively related to ΔMTV (r = .77, P < .0001). In a multivariable model that predicted ΔMTV, PRM SUVloBFlo, which combines both PET/CT and DCE CT, was the only significant variable (β = 1.825, P = .03), dominating both imaging modalities independently. CONCLUSIONS PRM was applied in locally advanced cervical carcinoma treated definitively with chemoradiation, and radioresistant subvolumes were identified that correlated with changes in MTV and predicted treatment response. Identification of these subvolumes may assist in clinical decision making to tailor therapies, such as brachytherapy, in an effort to improve patient outcomes.
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Affiliation(s)
- Dante P I Capaldi
- Department of Radiation Oncology, School of Medicine, Stanford University, Stanford, California
| | - Dimitre H Hristov
- Department of Radiation Oncology, School of Medicine, Stanford University, Stanford, California
| | - Elizabeth A Kidd
- Department of Radiation Oncology, School of Medicine, Stanford University, Stanford, California.
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19
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Efficiency of Iterative Metal Artifact Reduction Algorithm (iMAR) Applied to Brain Volume Perfusion CT in the Follow-up of Patients after Coiling or Clipping of Ruptured Brain Aneurysms. Sci Rep 2019; 9:19423. [PMID: 31857627 PMCID: PMC6923436 DOI: 10.1038/s41598-019-55792-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Accepted: 12/02/2019] [Indexed: 01/10/2023] Open
Abstract
Metal artifacts resulting from coiling or clipping of a brain aneurysm degrade image quality and reduce diagnostic usefulness of computed tomography perfusion CTP. Our aim was to assess the diagnostic value of the iterative metal artifact reduction algorithm (iMAR) in CTP studies after coiling or clipping of ruptured intracranial aneurysms. Fifty-eight CTP exams performed in 32 patients were analysed. iMAR was applied to the source images from the CT scanner. Perfusion maps were generated from datasets both with and without iMAR, and both datasets were compared qualitatively and quantitatively. Qualitative analysis included evaluation of intensity of artifacts, image quality, presence of new artifacts, and the reader’s confidence in their diagnosis as well as diagnostic impression. Quantitative analysis included evaluation of tissue attenuation curves, evaluation of region of interest (ROI)-based measurement of perfusion values at levels that do and do not contain metal, compared to previously published reference ranges of perfusion values. Our results showed that application of iMAR reduced artifacts and significantly improved image quality. New artifacts were observed adjacent to metallic implants, but did not limit the evaluation of other regions. After correction for artifact readers’ confidence in their diagnosis increased from 41.3% to 87.9%, and the diagnostic impression changed in 31% of the exams. No difference between tissue attenuation curves was found. For slices without metal, no difference was noted between values measured before and after iMAR, and the total number of ROIs in the reference range of perfusion values was unchanged. At the level of the metal implant, 89.85% of ROIs obtained before using iMAR showed calculation errors. After using iMAR, only 1.7% showed errors. Before iMAR 3.1% of values were in the reference range, whereas after iMAR this increased to 33.1%. In conclusion, our results show that iMAR is an excellent tool for reducing artifacts in CTP. It is therefore recommended for use in clinical practice, particularly when severe artifacts are present, or when hypoperfusion is suspected at the level of the coil or clip. After the application of iMAR, the perfusion values at the level of the metal can be better calculated, but may not lie within the reference range; therefore, quantitative analysis at the level of artifacts is not advisable.
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20
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Adebayo OD, Culpan G. Diagnostic accuracy of computed tomography perfusion in the prediction of haemorrhagic transformation and patient outcome in acute ischaemic stroke: A systematic review and meta-analysis. Eur Stroke J 2019; 5:4-16. [PMID: 32232165 DOI: 10.1177/2396987319883461] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 09/23/2019] [Indexed: 01/23/2023] Open
Abstract
Purpose The aim of this systematic review and meta-analysis is to determine the diagnostic accuracy of computed tomography brain perfusion in the prediction of haemorrhagic transformation and patient outcome in acute ischaemic stroke. Method Electronic databases and grey literature published over the last 10 years related to healthcare and radiology were searched using the key terms: 'computed tomography perfusion', 'haemorrhagic transformation', 'acute ischaemic stroke', 'functional outcome' and their synonyms using both UK and American spellings. Inclusion criteria were: sample size at least 30 patients, original research, evaluate ability of computed tomography perfusion to predict haemorrhagic transformation, reports diagnostic accuracy or provide relevant data for a 2 × 2 contingency table, use follow-up non-contrast computed tomography (NCCT) or magnetic resonance imaging as reference standard. Findings Twelve studies were included in the review; studies cover a total of 808 patients. Haemorrhagic transformation occurred in 30.2% of patients. Pooled sensitivity and specificity were 85.9% (95% CI; 65-97%), 73.9% (95% CI; 45-92%) and accuracy of 79.1% (95% CI; 57-98%). Pooled NPV was 92.9% with a high false positive rate (19.8%), which could be explained in terms of outcome classification, acquisition artefact and computed tomography perfusion processing algorithms. Discussion This review evaluated the importance of using pre-defined threshold measurement for optimal prediction of HT, the relevance of patient pre-treatment clinical parameters to HT occurrence, the CTP parameters and the measurements that are independent predictors of HT, the significance of rtPA rather as an exacerbator of HT and the impact of both minor and major HT/PH on patient 20 functional outcome. Conclusion Computed tomography perfusion has a high sensitivity and moderately high specificity for prediction of haemorrhagic transformation in acute ischaemic stroke. Pre-treatment clinical decision making requires consideration of clinical factors in addition to imaging findings. This systematic review and meta-analysis highlights that pre-treatment computed tomography perfusion adds to clinical confidence by predicting potential for haemorrhage, both in thrombolysed and un-thrombolysed patients, and also influences decisions about alternative treatments for acute ischaemic stroke patients.
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Affiliation(s)
- Olushola D Adebayo
- Mercy University Hospital Cork, Cork, Republic of Ireland
- Faculty of Health Sciences, University of Bradford, Bradford, UK
| | - Gary Culpan
- Faculty of Health Sciences, University of Bradford, Bradford, UK
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Choi WJ, Li Y, Wang RK. Monitoring Acute Stroke Progression: Multi-Parametric OCT Imaging of Cortical Perfusion, Flow, and Tissue Scattering in a Mouse Model of Permanent Focal Ischemia. IEEE TRANSACTIONS ON MEDICAL IMAGING 2019; 38:1427-1437. [PMID: 30714910 PMCID: PMC6660833 DOI: 10.1109/tmi.2019.2895779] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/20/2023]
Abstract
Cerebral ischemic stroke causes injury to brain tissue characterized by a complex cascade of neuronal and vascular events. Imaging during the early stages of its development allows prediction of tissue infarction and penumbra so that optimal intervention can be determined in order to salvage brain function impairment. Therefore, there is a critical need for novel imaging techniques that can characterize brain injury in the earliest phases of the ischemic stroke. This paper examined optical coherence tomography (OCT) for imaging acute injury in experimental ischemic stroke in vivo. Based on endogenous optical scattering signals provided by OCT imaging, we have developed a single, integrated imaging platform enabling the measurement of changes in blood perfusion, blood flow, erythrocyte velocity, and light attenuation within a cortical tissue, during focal cerebral ischemia in a mouse model. During the acute phase (from 5 min to the first few hours following the blood occlusion), the multi-parametric OCT imaging revealed multiple hemodynamic and tissue scattering responses in vivo, including cerebral blood flow deficits, capillary non-perfusion, displacement of penetrating vessels, and increased light attenuation in the cortical tissue at risk that are spatially correlated with the infarct core, as determined by postmortem staining with triphenyltetrazolium chloride. The use of multi-parametric OCT imaging may aid in the comprehensive evaluation of ischemic lesions during the early stages of stroke, thereby providing essential knowledge for guiding treatment decisions.
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Affiliation(s)
- Woo June Choi
- School of Electrical and Electronics Engineering, College of ICT Engineering, Chung-Ang University, Seoul, 06974, Korea
| | - Yuandong Li
- Department of Bioengineering, University of Washington, Seattle WA 98195, USA
| | - Ruikang K. Wang
- Corresponding author, phone: 206-616-5025; fax: 206-616-5025;
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22
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Vulcu S, Wagner F, Santos AF, Reitmeir R, Söll N, Schöni D, Fung C, Wiest R, Raabe A, Beck J, Z’Graggen WJ. Repetitive Computed Tomography Perfusion for Detection of Cerebral Vasospasm–Related Hypoperfusion in Aneurysmal Subarachnoid Hemorrhage. World Neurosurg 2019; 121:e739-e746. [DOI: 10.1016/j.wneu.2018.09.208] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2018] [Revised: 09/25/2018] [Accepted: 09/26/2018] [Indexed: 11/27/2022]
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Skornitzke S, Hirsch J, Kauczor HU, Stiller W. Evaluation of the effect of image noise on CT perfusion measurements using digital perfusion phantoms. Eur Radiol 2018; 29:2089-2097. [PMID: 30311031 DOI: 10.1007/s00330-018-5709-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2018] [Revised: 07/05/2018] [Accepted: 08/06/2018] [Indexed: 12/14/2022]
Abstract
OBJECTIVES To assess the influence of image noise on computed tomography (CT) perfusion studies, CT perfusion software algorithms were evaluated for susceptibility to image noise and results applied to clinical perfusion studies. METHODS Digital perfusion phantoms were generated using a published deconvolution model to create time-attenuation curves (TACs) for 16 different combinations of blood flow (BF; 30/60/90/120 ml/100 ml/min) and flow extraction product (FEP; 10/20/30/40 ml/100 ml/min) corresponding to values encountered in clinical studies. TACs were distorted with Gaussian noise at 50 different strengths to approximate image noise, performing 200 repetitions for each noise level. A total of 160,000 TACs were evaluated by measuring BF and FEP with CT perfusion software, comparing results for the maximum slope and Patlak models with those obtained with a deconvolution model. To translate results to clinical practice, data of 23 patients from a CT perfusion study were assessed for image noise, and the accuracy of reported CT perfusion measurements was estimated. RESULTS Perfusion measurements depend on image noise as means and standard deviations of BF and FEP over repetitions increase with increasing image noise, especially for low BF and FEP values. BF measurements derived by deconvolution show larger standard deviations than those performed with the maximum slope model. Image noise in the evaluated CT perfusion study was 26.46 ± 3.52 HU, indicating possible overestimation of BF by up to 85% in a clinical setting. CONCLUSIONS Measurements of perfusion parameters depend heavily upon the magnitude of image noise, which has to be taken into account during selection of acquisition parameters and interpretation of results, e.g., as a quantitative imaging biomarker. KEY POINTS • CT perfusion results depend heavily upon the magnitude of image noise. • Different CT perfusion models react differently to the presence of image noise. • Blood flow may be overestimated by 85% in clinical CT perfusion studies.
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Affiliation(s)
- Stephan Skornitzke
- Diagnostic & Interventional Radiology (DIR), Heidelberg University Hospital, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany
| | - Jessica Hirsch
- CHRESTOS Institut, Emil-Figge-Straße 43, 44227, Dortmund, Germany
| | - Hans-Ulrich Kauczor
- Diagnostic & Interventional Radiology (DIR), Heidelberg University Hospital, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany
| | - Wolfram Stiller
- Diagnostic & Interventional Radiology (DIR), Heidelberg University Hospital, Im Neuenheimer Feld 110, 69120, Heidelberg, Germany.
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25
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Egger K, Strecker C, Kellner E, Urbach H. [Imaging in acute ischemic stroke using automated postprocessing algorithms]. DER NERVENARZT 2018; 89:885-894. [PMID: 29947938 DOI: 10.1007/s00115-018-0535-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
There are several automated analytical methods to detect thromboembolic vascular occlusions, the infarct core and the potential infarct-endangered tissue (tissue at risk) by means of multimodal computed tomography (CT) and magnetic resonance imaging (MRI). The infarct core is more reliably visualized by diffusion-weighted imaging (DWI) MRI or CT perfusion than by native CT. The extent of tissue at risk and endangerment can only be estimated; however, it seems essential whether "tissue at risk" actually exists. To ensure consistent patient care, uniform imaging protocols should be acquired in the referring hospital and thrombectomy center and the collected data should be standardized and automatically evaluated and presented. Whether patients with a large infarct core and with or without tissue at risk or patients with large vessel occlusion (LVO) but low NIHSS benefit from thrombectomy has to be evaluated in controlled clinical trials using standardized imaging protocols. A promising, potentially time-saving approach is also native CT and CT angiography using a flat-panel detector angiography system for assessment of vessel occlusion and leptomeningeal collaterals.
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Affiliation(s)
- K Egger
- Neurozentrum, Klinik für Neuroradiologie, Universitätsklinikum Freiburg, Medizinische Fakultät, Albert-Ludwigs-Universität Freiburg, Breisacher Str. 64, 79106, Freiburg, Deutschland.
| | - C Strecker
- Klinik für Neurologie, Universitätsklinikum Freiburg, Medizinische Fakultät, Albert-Ludwigs-Universität Freiburg, Freiburg, Deutschland
| | - E Kellner
- Abteilung Medizinische Physik Universitätsklinikum Freiburg, Medizinische Fakultät, Albert-Ludwigs-Universität Freiburg, Freiburg, Deutschland
| | - H Urbach
- Neurozentrum, Klinik für Neuroradiologie, Universitätsklinikum Freiburg, Medizinische Fakultät, Albert-Ludwigs-Universität Freiburg, Breisacher Str. 64, 79106, Freiburg, Deutschland
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26
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Banks TI, von Eyben R, Hristov D, Kidd EA. Pilot study of combined FDG-PET and dynamic contrast-enhanced CT of locally advanced cervical carcinoma before and during concurrent chemoradiotherapy suggests association between changes in tumor blood volume and treatment response. Cancer Med 2018; 7:3642-3651. [PMID: 29963760 PMCID: PMC6089147 DOI: 10.1002/cam4.1632] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2018] [Revised: 05/30/2018] [Accepted: 06/01/2018] [Indexed: 12/26/2022] Open
Abstract
Modern PET/CT radiotherapy simulators offer FDG-PET and dynamic contrast-enhanced (DCE) CT imaging for combined volumetric assessment of tumor metabolism and perfusion. However, the clinical utility of such assessment has not been clearly defined. Thus, in a prospective longitudinal study of primary cervical tumors treated with concurrent chemoradiotherapy (CCRT) we evaluated: (1) whether PET and perfusion parameters correlate or provide complementary information; (2) what imaging changes occur during CCRT; and (3) whether any parameters are predictive of treatment response as assessed by PET/CT 3 months posttherapy. FDG-PET/CT and DCE-CT scans were performed on 21 patients prior to and during CCRT. Coregistered volumetric parametric maps of standardized uptake value (SUV) measures and perfusion parameters blood flow (BF), blood volume (BV), and permeability were generated. Summary statistics for these parameters and their changes were calculated within the metabolic tumor volume (MTV). Correlations between SUV and BF/BV/permeability on local and global bases were assessed with Pearson's coefficient r. MTV, maximum SUV, and mean SUV decreased significantly between the pre- and during-treatment time points, while mean BV and permeability increased significantly. Global correlations between mean BF/BV/permeability and mean SUV values (-.15 < r < .29) were at most moderate. An increase in mean tumor BV during treatment was significantly correlated with complete metabolic response on 3-month posttreatment PET/CT. Weak correlations of SUV and perfusion parameters suggest a complementary role of FDG-PET and DCE-CT for tumor characterization. The association between relative change in mean BV and outcome suggests a potential role for DCE-CT in early evaluation of cervical tumor response to chemoradiotherapy.
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Affiliation(s)
- Thomas I Banks
- Department of Radiation Oncology, School of Medicine, Stanford University, Stanford, CA, USA
| | - Rie von Eyben
- Department of Radiation Oncology, School of Medicine, Stanford University, Stanford, CA, USA
| | - Dimitre Hristov
- Department of Radiation Oncology, School of Medicine, Stanford University, Stanford, CA, USA
| | - Elizabeth A Kidd
- Department of Radiation Oncology, School of Medicine, Stanford University, Stanford, CA, USA
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Wannamaker R, Guinand T, Menon BK, Demchuk A, Goyal M, Frei D, Bharatha A, Jovin TG, Shankar J, Krings T, Baxter B, Holmstedt C, Swartz R, Dowlatshahi D, Chan R, Tampieri D, Choe H, Burns P, Gentile N, Rempel J, Shuaib A, Buck B, Bivard A, Hill M, Butcher K. Computed Tomographic Perfusion Predicts Poor Outcomes in a Randomized Trial of Endovascular Therapy. Stroke 2018; 49:1426-1433. [DOI: 10.1161/strokeaha.117.019806] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 03/02/2018] [Accepted: 04/03/2018] [Indexed: 12/30/2022]
Abstract
Background and Purpose—
In the ESCAPE trial (Endovascular Treatment for Small Core and Anterior Circulation Proximal Occlusion with Emphasis on Minimizing CT to Recanalization Times), patients with large vessel occlusions and small infarct cores identified with computed tomography (CT)/CT angiography were randomized to endovascular therapy or standard of care. CT perfusion (CTP) was obtained in some cases but was not used to select patients. We tested the hypothesis that patients with penumbral CTP patterns have higher rates of good clinical outcome.
Methods—
All CTP data acquired in ESCAPE patients were analyzed centrally using a semiautomated perfusion threshold-based approach. A penumbral pattern was defined as an infarct core <70 mL, penumbral volume >15 mL, and a total hypoperfused volume:core volume ratio of >1.8. The primary outcome was good functional outcome at 90 days (modified Rankin Scale score, 0–2).
Results—
CTP was acquired in 138 of 316 ESCAPE patients. Penumbral patterns were present in 116 of 128 (90.6%) of patients with interpretable CTP data. The rate of good functional outcome in penumbral pattern patients (53 of 114; 46%) was higher than that in nonpenumbral patients (2 of 12; 17%;
P
=0.041). In penumbral patients, endovascular therapy increased the likelihood of a good clinical outcome (34 of 58; 57%) compared with those in the control group (19 of 58; 33%; odds ratio, 2.68; 95% confidence interval, 1.25–5.76;
P
=0.011). Only 3 of 12 nonpenumbral patients were randomized to the endovascular group, preventing an analysis of treatment effect.
Conclusions—
The majority of patients with CTP imaging in the ESCAPE trial had penumbral patterns, which were associated with better outcomes overall. Patients with penumbra treated with endovascular therapy had the greatest odds of good functional outcome. Nonpenumbral patients were much less likely to achieve good outcomes.
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Affiliation(s)
| | - Taurian Guinand
- From the Division of Neurology (R.W., T.G., A.S., B. Buck, K.B.)
| | - Bijoy K. Menon
- Division of Neurology, University of Calgary, Alberta, Canada (B.K.M., A.D., M.G., M.H.)
| | - Andrew Demchuk
- Division of Neurology, University of Calgary, Alberta, Canada (B.K.M., A.D., M.G., M.H.)
| | - Mayank Goyal
- Division of Neurology, University of Calgary, Alberta, Canada (B.K.M., A.D., M.G., M.H.)
| | - Donald Frei
- Department of Medical Imaging, Swedish Medical Center, Denver, CO (D.F.)
| | - Aditya Bharatha
- Department of Medical Imaging, St. Michael’s Hospital (A. Bharatha)
| | | | - Jai Shankar
- Department of Diagnostic Radiology, Dalhousie University, Halifax, Nova Scotia, Canada (J.S.)
| | | | - Blaise Baxter
- Department of Radiology, University of Tennessee, Chattanooga (B. Baxter)
| | - Christine Holmstedt
- Division of Neurology, Medical University of South Carolina, Charleston (C.H.)
| | - Richard Swartz
- Division of Neurology (R.S.), University of Toronto, Ontario, Canada
| | - Dar Dowlatshahi
- Division of Neurology, Ottawa Hospital Research Institute, University of Ottawa, Ontario, Canada (D.D.)
| | - Richard Chan
- Division of Neurology, University of Western Ontario, London, Canada (R.C.)
| | - Donatella Tampieri
- Department of Radiology, McGill University Health Center, Montreal, Quebec, Canada (D.T.)
| | - Hana Choe
- Neurovascular Associates, Abington Jefferson Health, Philadelphia, PA (H.C.)
| | - Paul Burns
- Division of Neurology, Royal Victoria Hospital, Belfast, United Kingdom (P.B.)
| | - Nina Gentile
- Division of Neurology, Temple University, Philadelphia, PA (N.G.)
| | - Jeremy Rempel
- Department of Diagnostic Imaging (J.R.), University of Alberta, Edmonton, Canada
| | - Ashfaq Shuaib
- From the Division of Neurology (R.W., T.G., A.S., B. Buck, K.B.)
| | - Brian Buck
- From the Division of Neurology (R.W., T.G., A.S., B. Buck, K.B.)
| | - Andrew Bivard
- Hunter Medical Research Institute, University of Newcastle, New South Wales, Australia (A. Bivard)
| | - Michael Hill
- Division of Neurology, University of Calgary, Alberta, Canada (B.K.M., A.D., M.G., M.H.)
| | - Kenneth Butcher
- From the Division of Neurology (R.W., T.G., A.S., B. Buck, K.B.)
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Schneider T, Kemmling A, Schroeder J, Pantel K, Glatzel M, Schoen G, Mohme M, Fiehler J, Gellißen S. Inverse Perfusion Requirements of Supra- and Infratentorial Brain Metastases Formation. Front Neurol 2018; 9:391. [PMID: 29899729 PMCID: PMC5989059 DOI: 10.3389/fneur.2018.00391] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2018] [Accepted: 05/14/2018] [Indexed: 12/21/2022] Open
Abstract
Background and Aims: Vascular border zones and the gray-white matter junction are preferred sites for the development of brain metastases (BM), whereas microvascular lesions are known to be a protective factor. In this proof of concept study, we aim to study the relationship of blood perfusion and the spatial distribution of BM. Materials and Methods: An average CT perfusion atlas of 107 healthy patients was created. Voxel-wise reference perfusion values were extracted from BM-negative and BM-positive regions in a second cohort of 100 untreated patients harboring 809 BM confirmed by MRI. A comparison of regional perfusion values was performed using the independent t-test. Results: In contrast to supratentorial BM that develop preferably in areas with lower CBV/CBF and longer MTT/TTP compared to the average regional perfusion (p < 0.001), infratentorial BM showed a higher CBV/CBF and shorter MTT/TTP (p < 0.001). Conclusion: Our results imply differing pathophysiological mechanisms underlying supra- and infratentorial BM spreading. The inverse perfusion patterns may result from differences in vascular supply, hemodynamic requirements, and/or production of pro-angiogenic factors.
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Affiliation(s)
- Tanja Schneider
- Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,Department of Radiology, Schoen Klinik Hamburg Eilbek, Hamburg, Germany
| | - André Kemmling
- Department of Neuroradiology, University Medical Center Schleswig-Holstein, Luebeck, Germany
| | - Julian Schroeder
- Department of Neurology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Klaus Pantel
- Center for Experimental Medicine, Institute of Tumor Biology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Markus Glatzel
- Center for Diagnostics, Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Gerhard Schoen
- Department of Medical Biometry and Epidemiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Malte Mohme
- Department of Neurosurgery, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Jens Fiehler
- Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Susanne Gellißen
- Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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Hemodynamic Forces Tune the Arrest, Adhesion, and Extravasation of Circulating Tumor Cells. Dev Cell 2018; 45:33-52.e12. [PMID: 29634935 DOI: 10.1016/j.devcel.2018.02.015] [Citation(s) in RCA: 180] [Impact Index Per Article: 30.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Revised: 01/05/2018] [Accepted: 02/16/2018] [Indexed: 02/07/2023]
Abstract
Metastatic seeding is driven by cell-intrinsic and environmental cues, yet the contribution of biomechanics is poorly known. We aim to elucidate the impact of blood flow on the arrest and the extravasation of circulating tumor cells (CTCs) in vivo. Using the zebrafish embryo, we show that arrest of CTCs occurs in vessels with favorable flow profiles where flow forces control the adhesion efficacy of CTCs to the endothelium. We biophysically identified the threshold values of flow and adhesion forces allowing successful arrest of CTCs. In addition, flow forces fine-tune tumor cell extravasation by impairing the remodeling properties of the endothelium. Importantly, we also observe endothelial remodeling at arrest sites of CTCs in mouse brain capillaries. Finally, we observed that human supratentorial brain metastases preferably develop in areas with low perfusion. These results demonstrate that hemodynamic profiles at metastatic sites regulate key steps of extravasation preceding metastatic outgrowth.
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The feasibility of low-concentration contrast and low tube voltage in computed tomography perfusion imaging: an animal study. Biosci Rep 2018; 38:BSR20170977. [PMID: 29208767 PMCID: PMC6435459 DOI: 10.1042/bsr20170977] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2017] [Revised: 11/23/2017] [Accepted: 12/04/2017] [Indexed: 11/24/2022] Open
Abstract
Aim: To investigate the feasibility of low-concentration contrast (270 mg/ml) together with low tube voltage (80 kV) and adaptive iterative dose reduction (AIDR)-3D reconstruction in liver computed tomography (CT) perfusion imaging. Method: A total of 15 healthy New Zealand rabbits received two CT scans each. The first scan (control) was acquired at 100 kV and 100 mA with iopromide (370 mg/ml), while the second scan (experimental) was acquired at 80 kV and 100 mA with iodixanol (270 mg/ml) 24 h after the first scan. The obtained images were reconstructed with filtered back projection (FBP) and AIDR-3D in the control and experimental groups respectively. The perfusion parameters (hepatic artery perfusion [HAP], portal vein perfusion [PVP], hepatic perfusion index [HPI], and total liver perfusion [TLP]) and image quality (image quality score, average CT value of abdomen aorta, signal-to-noise ratio [SNR], contrast-to-noise ratio [CNR], and figure of merit [FOM]) were compared using a paired t-test or Mann–Whitney U test between the two groups, when appropriate. The effective radiation dose and iodine intake were also recorded and compared. Results: With the exception of the FOM criteria, the image quality and perfusion parameters were not significantly different between the two groups. The effective radiation dose and iodine intake were 38.79% and 27.03% lower respectively, in the experimental group. Conclusion: Low-concentration contrast (iodixanol, 270 mg/ml) together with low tube voltage (80 kV) and AIDR-3D reconstruction help to reduce radiation dose and iodine intake without compromising perfusion parameters and image quality in liver CT perfusion imaging.
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Afat S, Brockmann C, Nikoubashman O, Müller M, Thierfelder KM, Kunz WG, Haberland U, Brockmann MA, Nikolaou K, Wiesmann M, Othman AE. Diagnostic performance of different perfusion algorithms for the detection of angiographical spasm. J Neuroradiol 2018; 45:290-294. [PMID: 29412162 DOI: 10.1016/j.neurad.2017.12.020] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 06/16/2017] [Accepted: 12/14/2017] [Indexed: 10/18/2022]
Abstract
PURPOSE To assess the diagnostic utility of different perfusion algorithms for the detection of angiographical terial spasm. METHOD During a 2-year period, 45 datasets from 29 patients (54.2±10,75y, 20F) with suspected cerebral vasospasm after aneurysmal subarachnoid hemorrhage were included. Volume Perfusion CT (VPCT), Non-enhanced CT (NCT) and angiography were performed within 6hours post-ictus. Perfusion maps were generated using a maximum slope (MS) and a deconvolution-based approach (DC). Two blinded neuroradiologists independently evaluated MS and DC maps regarding vasospasm-related perfusion impairment on a 3-point Likert-scale (0=no impairment, 1=impairment affecting <50%, 2=impairment affecting >50% of vascular territory). A third independent neuroradiologist assessed angiography for presence and severity of arterial narrowing on a 3-point Likert scale (0=no narrowing, 1=narrowing affecting <50%, 2=narrowing affecting>50% of artery diameter). MS and DC perfusion maps were evaluated regarding diagnostic accuracy for angiographical arterial spasm with angiography as reference standard. Correlation analysis of angiography findings with both MS and DC perfusion maps was additionally performed. Furthermor, the agreement between MS and DC and inter-reader agreement was assessed. RESULTS DC maps yielded significantly higher diagnostic accuracy than MS perfusion maps (DC:AUC=.870; MS:AUC=.805; P=0.007) with higher sensitivity for DC compared to MS (DC:sensitivity=.758; MS:sensitivity=.625). DC maps revealed stronger correlation with angiography than MS (DC: R=.788; MS: R=694;=<0.001). MS and DC showed substantial agreement (Kappa=.626). Regarding inter-reader analysis, (almost) perfect inter-reader agreement was observed for both MS and DC maps (Kappa≥981). CONCLUSION DC yields significantly higher diagnostic accuracy for the detection of angiographic arterial spasm and higher correlation with angiographic findings compared to MS.
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Affiliation(s)
- Saif Afat
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, 52074 Aachen, Germany
| | - Carolin Brockmann
- Department of Neuroradiology, University Hospital Mainz, 55131 Mainz, Germany
| | - Omid Nikoubashman
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, 52074 Aachen, Germany; Department of Diagnostic and Interventional Radiology, RWTH Aachen University, 52074 Aachen, Germany
| | - Marguerite Müller
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, 52074 Aachen, Germany
| | - Kolja M Thierfelder
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Marchioninistr. 15, 81377 Munich, Germany
| | - Wolfgang G Kunz
- Institute for Clinical Radiology, Ludwig-Maximilians-University Hospital Munich, Marchioninistr. 15, 81377 Munich, Germany
| | | | - Marc A Brockmann
- Department of Neuroradiology, University Hospital Mainz, 55131 Mainz, Germany
| | - Konstantin Nikolaou
- Department for Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tübingen, Germany
| | - Martin Wiesmann
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, 52074 Aachen, Germany
| | - Ahmed E Othman
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, 52074 Aachen, Germany; Siemens Healthcare GmbH, 91052 Forchheim, Germany.
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Kate M, Wannamaker R, Kamble H, Riaz P, Gioia LC, Buck B, Jeerakathil T, Smyth P, Shuaib A, Emery D, Butcher K. Penumbral Imaging-Based Thrombolysis with Tenecteplase Is Feasible up to 24 Hours after Symptom Onset. J Stroke 2018; 20:122-130. [PMID: 29402060 PMCID: PMC5836582 DOI: 10.5853/jos.2017.00178] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 09/20/2017] [Accepted: 09/21/2017] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND AND PURPOSE Thrombolysis >4.5 hours after ischemic stroke onset is unproven. We assessed the feasibility of tenecteplase (TNK) treatment in patients with evidence of an ischemic penumbra 4.5 to 24 hours after onset. METHODS Acute ischemic stroke patients underwent perfusion computed tomography (CT)/magnetic resonance imaging. Patients with cerebral blood volume (CBV) or diffusion weighted imaging Alberta Stroke Program Early CT Scores (ASPECTS) >6 and mismatch score >2 (defined as >2 ASPECTS regions with delay on mean transit time maps and normal CBV) were eligible for treatment with TNK (0.25 mg/kg). Patients with mismatch patterns enrolled in non-endovascular/non-thrombolysis trials and those without mismatch patterns served as comparators. RESULTS The median (interquartile range) baseline National Institutes of Health Stroke Scale (NIHSS) in TNK treated patients (n=16) was 12 (range, 8 to 15). In the untreated mismatch (n=18) and nonmismatch (n=23) groups, the baseline NIHSS was 12 (range, 7 to 12) and 16 (range, 8 to 20; P=0.09) respectively. There was one symptomatic hemorrhage each in the TNK group (parenchymal hematoma [PH] 2) and non-mismatch group (PH 2). Penumbral salvage volumes were higher in TNK treated patients (48.3 mL [range, 24.9 to 80.4]) than the non-mismatch (-90.8 mL [range, -197 to -20]; P<0.0001) patients. CONCLUSIONS This prospective, non-randomized study supports the feasibility of TNK therapy in patients with evidence of ischemic penumbra 4 to 24 hours after onset.
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Affiliation(s)
- Mahesh Kate
- Division of Neurology, Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - Robert Wannamaker
- Division of Neurology, Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - Harsha Kamble
- Division of Neurology, Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - Parnian Riaz
- Division of Neurology, Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - Laura C Gioia
- Division of Neurology, Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - Brian Buck
- Division of Neurology, Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - Thomas Jeerakathil
- Division of Neurology, Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - Penelope Smyth
- Division of Neurology, Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - Ashfaq Shuaib
- Division of Neurology, Department of Medicine, University of Alberta, Edmonton, AB, Canada
| | - Derek Emery
- Department of Radiology and Diagnostic Imaging, University of Alberta, Edmonton, AB, Canada
| | - Kenneth Butcher
- Division of Neurology, Department of Medicine, University of Alberta, Edmonton, AB, Canada
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Austein F, Huhndorf M, Meyne J, Laufs H, Jansen O, Lindner T. Advanced CT for diagnosis of seizure-related stroke mimics. Eur Radiol 2017; 28:1791-1800. [DOI: 10.1007/s00330-017-5174-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2017] [Revised: 10/25/2017] [Accepted: 11/06/2017] [Indexed: 12/19/2022]
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CT-perfusion stroke imaging: a threshold free probabilistic approach to predict infarct volume compared to traditional ischemic thresholds. Sci Rep 2017; 7:6679. [PMID: 28751692 PMCID: PMC5532266 DOI: 10.1038/s41598-017-06882-w] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 06/19/2017] [Indexed: 11/25/2022] Open
Abstract
The aim was to evaluate a novel method of threshold-free prediction of brain infarct from computed tomography perfusion (CTP) imaging in comparison to conventional ischemic thresholds. In a multicenter cohort of 161 patients with acute large vessel occlusion who received endovascular therapy, brain infarction was predicted by CTP using (1) optimized parameter cut-off values determined by ROC curve analysis and (2) probabilistic logistic regression threshold-free analysis. Predicted infarct volumes and prediction errors based on four perfusion parameter maps were compared against observed infarcts. In 93 patients with successful recanalization, the mean observed infarct volume was 35.7 ± 61.9 ml (the reference for core infarct not savable by reperfusion). Optimal parameter thresholds predicted mean infarct volumes between 53.2 ± 44.4 and 125.0 ± 95.4 ml whereas threshold-free analysis predicted mean volumes between 35.9 ± 28.5 and 36.1 ± 29.0 ml. In 68 patients with persistent occlusion, the mean observed infarct volume was 113.4 ± 138.3 ml (the reference to define penumbral infarct savable by reperfusion). Predicted mean infarct volumes by parameter thresholds ranged from 91.4 ± 81.5 to 163.8 ± 135.7 ml, by threshold-free analysis from 113.2 ± 89.9 to 113.5 ± 89.0 ml. Threshold-free prediction of infarct volumes had a higher precision and lower patient-specific prediction error than conventional thresholding. Penumbra to core lesion mismatch estimate may therefore benefit from threshold-free CTP analysis.
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Shin DH, Klotz E, Kim EY. Single Subcortical Infarct: Pathomechanism Assessed by Thin-Section Computed Tomography Perfusion. J Stroke Cerebrovasc Dis 2017; 26:1440-1448. [DOI: 10.1016/j.jstrokecerebrovasdis.2017.03.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Revised: 02/16/2017] [Accepted: 03/20/2017] [Indexed: 10/19/2022] Open
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Minnerup J, Broocks G, Kalkoffen J, Langner S, Knauth M, Psychogios MN, Wersching H, Teuber A, Heindel W, Eckert B, Wiendl H, Schramm P, Fiehler J, Kemmling A. Computed tomography-based quantification of lesion water uptake identifies patients within 4.5 hours of stroke onset: A multicenter observational study. Ann Neurol 2017; 80:924-934. [PMID: 28001316 DOI: 10.1002/ana.24818] [Citation(s) in RCA: 83] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 11/02/2016] [Accepted: 11/02/2016] [Indexed: 11/07/2022]
Abstract
OBJECTIVE Many patients with stroke cannot receive intravenous thrombolysis because the time of symptom onset is unknown. We tested whether computed tomography (CT)-based quantification of water uptake in the ischemic tissue can identify patients with stroke onset within 4.5 hours, the time window of thrombolysis. METHODS Perfusion CT was used to identify ischemic brain tissue, and its density was measured in native CT and related to the density of the corresponding area of the contralateral hemisphere to quantify lesion water uptake. The optimal cutoff value of water uptake distinguishing stroke onset within and beyond 4.5 hours was calculated in patients with proximal middle cerebral artery occlusion (derivation cohort) with known time of symptom onset. The so-derived cutoff value was validated in a prospective cohort from other stroke centers. RESULTS Of 178 patients of the derivation cohort, 147 (82.6%) had CT within 4.5 hours. Percentage water uptake was significantly lower in patients with stroke onset within compared to beyond 4.5 hours. The area under the receiver operating characteristic curve for distinguishing these patient groups according to percentage water uptake was 0.999 (95% confidence interval = 0.996-1.000, p < 0.001) with an optimal cutoff value of 11.5%. Applying this cutoff to the validation cohort of 240 patients, sensitivity was 98.6%, specificity 90.5%, positive predictive value 99.1%, and negative predictive value 86.4%. INTERPRETATION Quantification of brain water uptake identifies stroke patients with symptom onset within 4.5 hours with high accuracy and may guide the decision to use thrombolysis in patients with unknown time of stroke onset. Ann Neurol 2016;80:924-934.
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Affiliation(s)
- Jens Minnerup
- Department of Neurology, University of Münster, Münster
| | - Gabriel Broocks
- Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Hamburg
| | | | - Soenke Langner
- Institute of Diagnostic Radiology and Neuroradiology, University of Medicine Greifswald, Greifswald
| | - Michael Knauth
- Institute for Diagnostic and Interventional Neuroradiology, University Medicine Göttingen, Göttingen
| | - Marios Nikos Psychogios
- Institute for Diagnostic and Interventional Neuroradiology, University Medicine Göttingen, Göttingen
| | - Heike Wersching
- Institute of Epidemiology and Social Medicine, University of Münster, Münster
| | - Anja Teuber
- Institute of Epidemiology and Social Medicine, University of Münster, Münster
| | - Walter Heindel
- Department of Clinical Radiology, University of Münster, Münster
| | - Bernd Eckert
- Department of Neuroradiology, Asklepios Hospital Altona, Hamburg
| | - Heinz Wiendl
- Department of Neurology, University of Münster, Münster
| | - Peter Schramm
- Institute of Neuroradiology, University Medical Center Schleswig-Holstein, Lübeck, Germany
| | - Jens Fiehler
- Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Hamburg
| | - André Kemmling
- Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Hamburg.,Department of Clinical Radiology, University of Münster, Münster.,Institute of Neuroradiology, University Medical Center Schleswig-Holstein, Lübeck, Germany
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Pisana F, Henzler T, Schönberg S, Klotz E, Schmidt B, Kachelrieß M. Noise reduction and functional maps image quality improvement in dynamic CT perfusion using a new k-means clustering guided bilateral filter (KMGB). Med Phys 2017; 44:3464-3482. [DOI: 10.1002/mp.12297] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 03/07/2017] [Accepted: 03/10/2017] [Indexed: 12/11/2022] Open
Affiliation(s)
- Francesco Pisana
- Medical Physics in Radiology; German Cancer Research Center (DKFZ); Heidelberg 69120 Germany
- CT Clinical Applications Predevelopment; Siemens Healthcare GmbH; Forchheim 91301 Germany
| | - Thomas Henzler
- Radiology and Nuclear Medicine Department; University Hospital of Mannheim; Mannheim 68167 Germany
| | - Stefan Schönberg
- Radiology and Nuclear Medicine Department; University Hospital of Mannheim; Mannheim 68167 Germany
| | - Ernst Klotz
- CT Clinical Applications Predevelopment; Siemens Healthcare GmbH; Forchheim 91301 Germany
| | - Bernhard Schmidt
- CT Clinical Applications Predevelopment; Siemens Healthcare GmbH; Forchheim 91301 Germany
| | - Marc Kachelrieß
- Medical Physics in Radiology; German Cancer Research Center (DKFZ); Heidelberg 69120 Germany
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Tamandl D, Waneck F, Sieghart W, Unterhumer S, Kölblinger C, Baltzer P, Ba-Ssalamah A, Loewe C. Early response evaluation using CT-perfusion one day after transarterial chemoembolization for HCC predicts treatment response and long-term disease control. Eur J Radiol 2017; 90:73-80. [PMID: 28583650 DOI: 10.1016/j.ejrad.2017.02.032] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Revised: 02/17/2017] [Accepted: 02/20/2017] [Indexed: 02/07/2023]
Abstract
PURPOSE To determine the value of CT perfusion (CTP) for early response assessment after transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC). MATERIALS AND METHODS Between April 2013 and April 2015, 41 HCC (16 patients) were included in this study. CT perfusion was performed before and one day after TACE. Blood flow (BF), blood volume (BV), time to start (TTS), arterial liver perfusion (ALP), portal liver perfusion (PVP) and hepatic perfusion index (HPI) were measured. Quantitative perfusion values before and after TACE were compared to the response assessed using mRECIST criteria six weeks after TACE and long-term outcome was assessed. RESULTS Twenty-one lesions (51%) had complete remission (CR) and five (12%) had partial response (PR) six weeks after TACE. CTP parameters were significantly reduced after TACE in responders (PR, CR, p<0.001) while no difference was observed in non-responders. ALPpost was superior in the prediction of CR compared to BFpost and BVpost (p<0.001) with a sensitivity, specificity, PPV, NPV, and accuracy of 90%, 90%, 91%, 90%, and 91%, respectively. Only 3/21 lesions with CR recurred, with a mean local-recurrence-free survival of 19.6 months. CONCLUSION CT perfusion detects lesions with complete response one day after TACE, and is a feasible tool for early response assessment.
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Affiliation(s)
- Dietmar Tamandl
- Department of Biomedical Imaging and Image-Guided Therapy, Division of General and Pediatric Radiology, Medical University of Vienna, Vienna, Austria
| | - Fredrik Waneck
- Department of Biomedical Imaging and Image-Guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University of Vienna, Vienna, Austria
| | - Wolfgang Sieghart
- Department of Internal Medicine, Division of Gastroenterology & Hepatology, Medical University of Vienna, Vienna, Austria
| | - Sylvia Unterhumer
- Department of Biomedical Imaging and Image-Guided Therapy, Division of General and Pediatric Radiology, Medical University of Vienna, Vienna, Austria; Department of Biomedical Imaging and Image-Guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University of Vienna, Vienna, Austria
| | | | - Pascal Baltzer
- Department of Biomedical Imaging and Image-Guided Therapy, Division of General and Pediatric Radiology, Medical University of Vienna, Vienna, Austria
| | - Ahmed Ba-Ssalamah
- Department of Biomedical Imaging and Image-Guided Therapy, Division of General and Pediatric Radiology, Medical University of Vienna, Vienna, Austria
| | - Christian Loewe
- Department of Biomedical Imaging and Image-Guided Therapy, Division of Cardiovascular and Interventional Radiology, Medical University of Vienna, Vienna, Austria.
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Austein F, Riedel C, Kerby T, Meyne J, Binder A, Lindner T, Huhndorf M, Wodarg F, Jansen O. Comparison of Perfusion CT Software to Predict the Final Infarct Volume After Thrombectomy. Stroke 2016; 47:2311-7. [DOI: 10.1161/strokeaha.116.013147] [Citation(s) in RCA: 142] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2016] [Accepted: 07/11/2016] [Indexed: 11/16/2022]
Abstract
Background and Purpose—
Computed tomographic perfusion represents an interesting physiological imaging modality to select patients for reperfusion therapy in acute ischemic stroke. The purpose of our study was to determine the accuracy of different commercial perfusion CT software packages (Philips (A), Siemens (B), and RAPID (C)) to predict the final infarct volume (FIV) after mechanical thrombectomy.
Methods—
Single-institutional computed tomographic perfusion data from 147 mechanically recanalized acute ischemic stroke patients were postprocessed. Ischemic core and FIV were compared about thrombolysis in cerebral infarction (TICI) score and time interval to reperfusion. FIV was measured at follow-up imaging between days 1 and 8 after stroke.
Results—
In 118 successfully recanalized patients (TICI 2b/3), a moderately to strongly positive correlation was observed between ischemic core and FIV. The highest accuracy and best correlation are shown in early and fully recanalized patients (Pearson
r
for A=0.42, B=0.64, and C=0.83;
P
<0.001). Bland–Altman plots and boxplots demonstrate smaller ranges in package C than in A and B. Significant differences were found between the packages about over- and underestimation of the ischemic core. Package A, compared with B and C, estimated more than twice as many patients with a malignant stroke profile (
P
<0.001). Package C best predicted hypoperfusion volume in nonsuccessfully recanalized patients.
Conclusions—
Our study demonstrates best accuracy and approximation between the results of a fully automated software (RAPID) and FIV, especially in early and fully recanalized patients. Furthermore, this software package overestimated the FIV to a significantly lower degree and estimated a malignant mismatch profile less often than other software.
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Affiliation(s)
- Friederike Austein
- Departments of Radiology and Neuroradiology (F.A., C.R., T.K., T.L., M.H., F.W., O.J.) and Neurology (J.M., A.B.), University Hospital, Schleswig-Holstein, Campus Kiel, Germany
| | - Christian Riedel
- Departments of Radiology and Neuroradiology (F.A., C.R., T.K., T.L., M.H., F.W., O.J.) and Neurology (J.M., A.B.), University Hospital, Schleswig-Holstein, Campus Kiel, Germany
| | - Tina Kerby
- Departments of Radiology and Neuroradiology (F.A., C.R., T.K., T.L., M.H., F.W., O.J.) and Neurology (J.M., A.B.), University Hospital, Schleswig-Holstein, Campus Kiel, Germany
| | - Johannes Meyne
- Departments of Radiology and Neuroradiology (F.A., C.R., T.K., T.L., M.H., F.W., O.J.) and Neurology (J.M., A.B.), University Hospital, Schleswig-Holstein, Campus Kiel, Germany
| | - Andreas Binder
- Departments of Radiology and Neuroradiology (F.A., C.R., T.K., T.L., M.H., F.W., O.J.) and Neurology (J.M., A.B.), University Hospital, Schleswig-Holstein, Campus Kiel, Germany
| | - Thomas Lindner
- Departments of Radiology and Neuroradiology (F.A., C.R., T.K., T.L., M.H., F.W., O.J.) and Neurology (J.M., A.B.), University Hospital, Schleswig-Holstein, Campus Kiel, Germany
| | - Monika Huhndorf
- Departments of Radiology and Neuroradiology (F.A., C.R., T.K., T.L., M.H., F.W., O.J.) and Neurology (J.M., A.B.), University Hospital, Schleswig-Holstein, Campus Kiel, Germany
| | - Fritz Wodarg
- Departments of Radiology and Neuroradiology (F.A., C.R., T.K., T.L., M.H., F.W., O.J.) and Neurology (J.M., A.B.), University Hospital, Schleswig-Holstein, Campus Kiel, Germany
| | - Olav Jansen
- Departments of Radiology and Neuroradiology (F.A., C.R., T.K., T.L., M.H., F.W., O.J.) and Neurology (J.M., A.B.), University Hospital, Schleswig-Holstein, Campus Kiel, Germany
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Sun Y, Yang M, Mao D, Lv F, Yin Y, Li M, Hua Y. Low-dose volume perfusion computed tomography (VPCT) for diagnosis of solitary pulmonary nodules. Eur J Radiol 2016; 85:1208-18. [DOI: 10.1016/j.ejrad.2016.03.026] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2015] [Revised: 03/26/2016] [Accepted: 03/29/2016] [Indexed: 01/31/2023]
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Othman AE, Afat S, Nikoubashman O, Müller M, Schubert GA, Bier G, Brockmann MA, Wiesmann M, Brockmann C. Volume perfusion CT imaging of cerebral vasospasm: diagnostic performance of different perfusion maps. Neuroradiology 2016; 58:787-92. [PMID: 27194077 DOI: 10.1007/s00234-016-1695-9] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2016] [Accepted: 05/03/2016] [Indexed: 10/21/2022]
Abstract
INTRODUCTION In this study, we aimed to evaluate the diagnostic performance of different volume perfusion CT (VPCT) maps regarding the detection of cerebral vasospasm compared to angiographic findings. METHODS Forty-one datasets of 26 patients (57.5 ± 10.8 years, 18 F) with subarachnoid hemorrhage and suspected cerebral vasospasm, who underwent VPCT and angiography within 6 h, were included. Two neuroradiologists independently evaluated the presence and severity of vasospasm on perfusion maps on a 3-point Likert scale (0-no vasospasm, 1-vasospasm affecting <50 %, 2-vasospasm affecting >50 % of vascular territory). A third neuroradiologist independently assessed angiography for the presence and severity of vasospasm on a 3-point Likert scale (0-no vasospasm, 1-vasospasm affecting < 50 %, 2-vasospasm affecting > 50 % of vessel diameter). Perfusion maps of cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT), and time to drain (TTD) were evaluated regarding diagnostic accuracy for cerebral vasospasm with angiography as reference standard. Correlation analysis of vasospasm severity on perfusion maps and angiographic images was performed. Furthermore, inter-reader agreement was assessed regarding findings on perfusion maps. RESULTS Diagnostic accuracy for TTD and MTT was significantly higher than for all other perfusion maps (TTD, AUC = 0.832; MTT, AUC = 0.791; p < 0.001). TTD revealed higher sensitivity than MTT (p = 0.007). The severity of vasospasm on TTD maps showed significantly higher correlation levels with angiography than all other perfusion maps (p ≤ 0.048). Inter-reader agreement was (almost) perfect for all perfusion maps (kappa ≥ 0.927). CONCLUSION The results of this study indicate that TTD maps have the highest sensitivity for the detection of cerebral vasospasm and highest correlation with angiography regarding the severity of vasospasm.
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Affiliation(s)
- Ahmed E Othman
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, Aachen, Germany. .,Department for Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076, Tübingen, Germany.
| | - Saif Afat
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, Aachen, Germany
| | - Omid Nikoubashman
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, Aachen, Germany
| | - Marguerite Müller
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, Aachen, Germany
| | | | - Georg Bier
- Department for Diagnostic and Interventional Neuroradiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, Tübingen, Germany
| | - Marc A Brockmann
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, Aachen, Germany.,Department of Neuroradiology, University Hospital Mainz, Mainz, Germany
| | - Martin Wiesmann
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, Aachen, Germany
| | - Carolin Brockmann
- Department of Diagnostic and Interventional Neuroradiology, RWTH Aachen University, Aachen, Germany
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Iterative Reconstruction Improves Both Objective and Subjective Image Quality in Acute Stroke CTP. PLoS One 2016; 11:e0150103. [PMID: 26930290 PMCID: PMC4773110 DOI: 10.1371/journal.pone.0150103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 02/09/2016] [Indexed: 11/19/2022] Open
Abstract
PURPOSE Computed tomography perfusion (CTP) imaging in acute ischemic stroke (AIS) suffers from measurement errors due to image noise. The purpose of this study was to investigate if iterative reconstruction (IR) algorithms can be used to improve the diagnostic value of standard-dose CTP in AIS. METHODS Twenty-three patients with AIS underwent CTP with standardized protocol and dose. Raw data were reconstructed with filtered back projection (FBP) and IR with intensity levels 3, 4, 5. Image quality was objectively (quantitative perfusion values, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR)) and subjectively (overall image quality) assessed. Ischemic core and perfusion mismatch were visually rated. Discriminative power for tissue outcome prediction was determined by the area under the receiver operating characteristic curve (AUC) resulting from the overlap between follow-up infarct lesions and stepwise thresholded CTP maps. RESULTS With increasing levels of IR, objective image quality (SNR and CNR in white matter and gray matter, elimination of error voxels) and subjective image quality improved. Using IR, mean transit time (MTT) was higher in ischemic lesions, while there was no significant change of cerebral blood volume (CBV) and cerebral blood flow (CBF). Visual assessments of perfusion mismatch changed in 4 patients, while the ischemic core remained constant in all cases. Discriminative power for infarct prediction as represented by AUC was not significantly changed in CBV, but increased in CBF and MTT (mean (95% CI)): 0.72 (0.67-0.76) vs. 0.74 (0.70-0.78) and 0.65 (0.62-0.67) vs 0.67 (0.64-0.70). CONCLUSION In acute stroke patients, IR improves objective and subjective image quality when applied to standard-dose CTP. This adds to the overall confidence of CTP in acute stroke triage.
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Added value of CT perfusion compared to CT angiography in predicting clinical outcomes of stroke patients treated with mechanical thrombectomy. Eur Radiol 2016; 26:4213-4219. [DOI: 10.1007/s00330-016-4257-y] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Revised: 01/18/2016] [Accepted: 01/28/2016] [Indexed: 11/30/2022]
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Image quality, radiation dose and diagnostic accuracy of 70 kVp whole brain volumetric CT perfusion imaging: a preliminary study. Eur Radiol 2016; 26:4184-4193. [DOI: 10.1007/s00330-016-4225-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 01/02/2016] [Accepted: 01/15/2016] [Indexed: 11/30/2022]
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Dynamic volume perfusion computed tomography parameters versus RECIST for the prediction of outcome in lung cancer patients treated with conventional chemotherapy. J Thorac Oncol 2015; 10:164-71. [PMID: 25247342 DOI: 10.1097/jto.0000000000000376] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
INTRODUCTION To compare dynamic volume perfusion computed tomography (dVPCT) parameters with Response Evaluation Criteria in Solid Tumors (RECIST 1.1) for prediction of therapy response and overall survival (OS) in non-small-cell lung cancer (NSCLC) and small-cell lung cancer (SCLC) patients treated with conventional chemotherapy. METHODS A total of 173 lung cancer patients (131 men; 61 ± 10 years) undergoing dVPCT before (T1) and after chemotherapy (T2) and follow-up were prospectively included. dVPCT-derived blood flow, blood volume, mean transit time, and permeability (PERM) were assessed, compared between NSCLC and SCLC and patients' response to therapy was determined according to RECIST 1.1. RESULTS One hundred of one hundred and seventy-three patients underwent dVPCT at T1 and T2 within a median of 44 (range, 31-108) days. dVPCT values were differing in NSCLC and SCLC, but were not significantly differing between patients with partial response, stable, or progressive disease. Eighty-five patients (NSCLC = 72 and SCLC = 13) with a follow-up for greater than or equal to 6 months were analyzed for OS. Fifty-six of eighty-five patients died during follow-up. Receiver operating characteristic analysis determined T1/T2 with highest predictive values regarding OS for blood flow, blood volume, mean transit time, and permeability (area under the curve: 0.53, 0.61, 0.54, and 0.53, respectively, all p > 0.05). Kaplan-Meier statistics revealed OS of patient groups assigned according to dVPCT T1/T2 cutoff values was not differing for neither dVPCT parameter, whereas RECIST groups significantly differed in OS (p = 0.02). Cox proportional hazards regression determined progressive disease status to independently predict OS (p = 0.004), while none of the dVPCT parameters did so. CONCLUSIONS dVPCT values, differ between NSCLC and SCLC, are not related to RECIST 1.1 classification and do not improve OS prediction in lung cancer patients treated with conventional chemotherapy.
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Kemmling A, Flottmann F, Forkert ND, Minnerup J, Heindel W, Thomalla G, Eckert B, Knauth M, Psychogios M, Langner S, Fiehler J. Multivariate dynamic prediction of ischemic infarction and tissue salvage as a function of time and degree of recanalization. J Cereb Blood Flow Metab 2015; 35:1397-405. [PMID: 26154867 PMCID: PMC4640330 DOI: 10.1038/jcbfm.2015.144] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/22/2015] [Revised: 04/01/2015] [Accepted: 04/02/2015] [Indexed: 01/19/2023]
Abstract
Benefit of endovascular recanalization beyond established treatment time windows likely exists in select stroke patients. However, there is currently no imaging model that predicts infarction adjusting for elapsed time between the pathologic snapshot of admission imaging until endovascular recanalization. We trained and cross validated a multivariate generalized linear model (GLM) that uses computer tomography perfusion and clinical data to quantify patient-specific dynamic change of tissue infarction depending on degree and time of recanalization. Multicenter data of 161 patients with proximal anterior circulation occlusion undergoing endovascular therapy were included. Multivariate voxelwise infarct probability was calculated within the GLM. The effect of increasing time to treatment and degree of recanalization on voxelwise infarction was calculated in each patient. Tissue benefit of successful relative to unsuccessful recanalization was shown up to 15 hours after onset in individual patients and decreased nonlinearly with time. On average, the relative reduction of infarct volume at the treatment interval of 5 hours was 53% and this salvage effect decreased by 5% units per hour to <5% after 10 additional hours to treatment. Treatment time-adjusted multivariate prediction of infarction by perfusion and clinical status may identify patients who benefit from extended time to recanalization therapy.
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Affiliation(s)
- André Kemmling
- Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,Department of Clinical Radiology, University of Muenster, Muenster, Germany.,Institute of Neuroradiology, University Medical Center Schleswig Holstein, Lübeck, Germany
| | - Fabian Flottmann
- Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Nils Daniel Forkert
- Department of Radiology and Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Jens Minnerup
- Department of Neurology, University of Muenster, Muenster, Germany
| | - Walter Heindel
- Department of Clinical Radiology, University of Muenster, Muenster, Germany
| | - Goetz Thomalla
- Department of Neurology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | - Bernd Eckert
- Department of Neuroradiology, Asklepios Hospital Altona, Hamburg, Germany
| | - Michael Knauth
- Department of Neuroradiology, University of Medicine Goettingen, Goettingen, Germany
| | - Marios Psychogios
- Department of Neuroradiology, University of Medicine Goettingen, Goettingen, Germany
| | - Soenke Langner
- Institute of Diagnostic Radiology and Neuroradiology, University of Medicine Greifswald, Greifswald, Germany
| | - Jens Fiehler
- Department of Diagnostic and Interventional Neuroradiology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
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Rudilosso S, Urra X, San Román L, Laredo C, López-Rueda A, Amaro S, Oleaga L, Chamorro Á. Perfusion Deficits and Mismatch in Patients with Acute Lacunar Infarcts Studied with Whole-Brain CT Perfusion. AJNR Am J Neuroradiol 2015; 36:1407-12. [PMID: 25882287 DOI: 10.3174/ajnr.a4303] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2014] [Accepted: 12/22/2014] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE The incidence and significance of perfusion abnormalities on brain imaging in patients with lacunar infarct are controversial. We studied the diagnostic yield of CTP and the type of perfusion abnormalities in patients presenting with a lacunar syndrome and in those with MR imaging-confirmed lacunar infarcts. MATERIALS AND METHODS A cohort of 33 patients with lacunar syndrome underwent whole-brain CTP on admission. Twenty-eight patients had an acute ischemic lesion at follow-up MR imaging; 16 were classified as lacunar infarcts. Two independent readers evaluated NCCT and CTP to compare their diagnostic yield. In patients with DWI-confirmed lacunar infarcts and visible deficits on CTP, the presence of mismatch tissue was measured by using different perfusion thresholds. RESULTS The symptomatic acute lesion was seen on CTP in 50% of patients presenting with a lacunar syndrome compared with only 17% on NCCT, and in 62% on CTP compared with 19% on NCCT, respectively, in patients with DWI-confirmed lacunar infarcts. CTP was more sensitive in supratentorial than in infratentorial lesions. In the nonblinded analysis, a perfusion deficit was observed in 12/16 patients with DWI-confirmed lacunar infarcts. The proportion of mismatch tissue was similar in patients with lacunar infarcts or nonlacunar strokes (32% versus 36%, P = .734). CONCLUSIONS Whole-brain CTP is superior to NCCT in identifying small ischemic lesions, including lacunar infarcts, in patients presenting with a lacunar syndrome. Perfusion deficits and mismatch are frequent in lacunar infarcts, but larger studies are warranted to elucidate the clinical significance of these CTP findings.
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Affiliation(s)
- S Rudilosso
- From the Functional Unit of Cerebrovascular Diseases (S.R., X.U., L.S.R., C.L., A.L.-R., S.A., L.O., Á.C.)
| | - X Urra
- From the Functional Unit of Cerebrovascular Diseases (S.R., X.U., L.S.R., C.L., A.L.-R., S.A., L.O., Á.C.) Institut d'Investigacions Biomèdiques August Pi i Sunyer (X.U., S.A., Á.C.), Barcelona, Spain
| | - L San Román
- From the Functional Unit of Cerebrovascular Diseases (S.R., X.U., L.S.R., C.L., A.L.-R., S.A., L.O., Á.C.) Department of Radiology (L.S.R., A.L.-R., L.O.), Hospital Clínic, Barcelona, Spain
| | - C Laredo
- From the Functional Unit of Cerebrovascular Diseases (S.R., X.U., L.S.R., C.L., A.L.-R., S.A., L.O., Á.C.)
| | - A López-Rueda
- From the Functional Unit of Cerebrovascular Diseases (S.R., X.U., L.S.R., C.L., A.L.-R., S.A., L.O., Á.C.) Department of Radiology (L.S.R., A.L.-R., L.O.), Hospital Clínic, Barcelona, Spain
| | - S Amaro
- From the Functional Unit of Cerebrovascular Diseases (S.R., X.U., L.S.R., C.L., A.L.-R., S.A., L.O., Á.C.) Institut d'Investigacions Biomèdiques August Pi i Sunyer (X.U., S.A., Á.C.), Barcelona, Spain
| | - L Oleaga
- From the Functional Unit of Cerebrovascular Diseases (S.R., X.U., L.S.R., C.L., A.L.-R., S.A., L.O., Á.C.) Department of Radiology (L.S.R., A.L.-R., L.O.), Hospital Clínic, Barcelona, Spain
| | - Á Chamorro
- From the Functional Unit of Cerebrovascular Diseases (S.R., X.U., L.S.R., C.L., A.L.-R., S.A., L.O., Á.C.) Institut d'Investigacions Biomèdiques August Pi i Sunyer (X.U., S.A., Á.C.), Barcelona, Spain Department of Medicine (Á.C.), School of Medicine, University of Barcelona, Barcelona. Spain
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48
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Morgan CD, Stephens M, Zuckerman SL, Waitara MS, Morone PJ, Dewan MC, Mocco J. Physiologic imaging in acute stroke: Patient selection. Interv Neuroradiol 2015; 21:499-510. [PMID: 26063695 DOI: 10.1177/1591019915587227] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Treatment of acute stroke is changing, as endovascular intervention becomes an important adjunct to tissue plasminogen activator. An increasing number of sophisticated physiologic imaging techniques have unique advantages and applications in the evaluation, diagnosis, and treatment-decision making of acute ischemic stroke. In this review, we first highlight the strengths, weaknesses, and possible indications for various stroke imaging techniques. How acute imaging findings in each modality have been used to predict functional outcome is discussed. Furthermore, there is an increasing emphasis on using these state-of-the-art imaging modalities to offer maximal patient benefit through IV therapy, endovascular thrombolytics, and clot retrieval. We review the burgeoning literature in the determination of stroke treatment based on acute, physiologic imaging findings.
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Affiliation(s)
- Clinton D Morgan
- Department of Neurological Surgery, Vanderbilt University School of Medicine, USA
| | | | - Scott L Zuckerman
- Department of Neurological Surgery, Vanderbilt University School of Medicine, USA
| | | | - Peter J Morone
- Department of Neurological Surgery, Vanderbilt University School of Medicine, USA
| | - Michael C Dewan
- Department of Neurological Surgery, Vanderbilt University School of Medicine, USA
| | - J Mocco
- Department of Neurosurgery, Icahn School of Medicine at Mouth Sinai, USA
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d'Esterre CD, Aviv RI, Morrison L, Fainardi E, Lee TY. Acute Multi-modal Neuroimaging in a Porcine Model of Endothelin-1-Induced Cerebral Ischemia: Defining the Acute Infarct Core. Transl Stroke Res 2015; 6:234-41. [PMID: 25876960 DOI: 10.1007/s12975-015-0394-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Revised: 03/02/2015] [Accepted: 03/08/2015] [Indexed: 12/01/2022]
Abstract
In a porcine ischemic stroke model, we sought to compare the acute predicted infarct core volume (PIV) defined by CT perfusion (CTP)-hemodynamic parameters and MR-diffusion-weighted imaging (MR-DWI)/apparent diffusion coefficient (ADC), with the true infarct core volume (TIV) as defined by histology. Ten Duroc-cross pigs had a CTP scan prior to injection of endothelin-1 (ET-1) into the left striatum. CTP scans were used to monitor ischemic progression. A second dose of ET-1 was injected 2 h from the first injection. The animal was moved to a 3-T MRI scanner where DWI was performed. CTP imaging was acquired immediately after the MR imaging. Next, the brain was removed and stained with tetrazolium chloride (TTC). Linear regression and Bland-Altman plots were used to correlate the PIV measured by each imaging modality to that of the TIV from the histological gold standard. The CTP-cerebral blood flow (CBF) parameter had the highest R (2) value and slope closest to unity, while the CTP-cerebral blood volume (CBV) had the lowest R(2) value and slope furthest away from unity. The CTP-CBF • CBV product parameter had a higher R(2) value but lower slope than both MR parameers. The best Bland-Altman agreement was observed with the CTP-CBF parameter. PIV from MR-DWI, ADC, and CTP-CBF overestimated the TIV defined with histology. We show that the PIV defined with absolute gray and white matter CT-CBF thresholds correlates best with the TIV and is similar to both MR-DWI and ADC-defined PIVs. Further, the acute CBF • CBV mismatch may not indicate penumbral tissue in the acute stroke setting.
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Affiliation(s)
- Christopher D d'Esterre
- Calgary Stroke Program, University of Calgary, 2500 University Dr NW, Calgary, AB, T2N 1N4, Canada
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50
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Delay-sensitive and delay-insensitive deconvolution perfusion-CT: similar ischemic core and penumbra volumes if appropriate threshold selected for each. Neuroradiology 2015; 57:573-81. [DOI: 10.1007/s00234-015-1507-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 02/25/2015] [Indexed: 11/30/2022]
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