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Serrallach BL, Mujanovic A, Ntoulias N, Manhart M, Branca M, Brehm A, Psychogios MN, Kurmann CC, Piechowiak EI, Pilgram-Pastor S, Meinel T, Seiffge D, Mordasini P, Gralla J, Dobrocky T, Kaesmacher J. Flat-panel Detector Perfusion Imaging and Conventional Multidetector Perfusion Imaging in Patients with Acute Ischemic Stroke : A Comparative Study. Clin Neuroradiol 2024; 34:625-635. [PMID: 38526586 PMCID: PMC11339100 DOI: 10.1007/s00062-024-01401-7] [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: 11/03/2023] [Accepted: 02/15/2024] [Indexed: 03/26/2024]
Abstract
PURPOSE Flat-panel detector computed tomography (FDCT) is increasingly used in (neuro)interventional angiography suites. This study aimed to compare FDCT perfusion (FDCTP) with conventional multidetector computed tomography perfusion (MDCTP) in patients with acute ischemic stroke. METHODS In this study, 19 patients with large vessel occlusion in the anterior circulation who had undergone mechanical thrombectomy, baseline MDCTP and pre-interventional FDCTP were included. Hypoperfused tissue volumes were manually segmented on time to maximum (Tmax) and time to peak (TTP) maps based on the maximum visible extent. Absolute and relative thresholds were applied to the maximum visible extent on Tmax and relative cerebral blood flow (rCBF) maps to delineate penumbra volumes and volumes with a high likelihood of irreversible infarcted tissue ("core"). Standard comparative metrics were used to evaluate the performance of FDCTP. RESULTS Strong correlations and robust agreement were found between manually segmented volumes on MDCTP and FDCTP Tmax maps (r = 0.85, 95% CI 0.65-0.94, p < 0.001; ICC = 0.85, 95% CI 0.69-0.94) and TTP maps (r = 0.91, 95% CI 0.78-0.97, p < 0.001; ICC = 0.90, 95% CI 0.78-0.96); however, direct quantitative comparisons using thresholding showed lower correlations and weaker agreement (MDCTP versus FDCTP Tmax 6 s: r = 0.35, 95% CI -0.13-0.69, p = 0.15; ICC = 0.32, 95% CI 0.07-0.75). Normalization techniques improved results for Tmax maps (r = 0.78, 95% CI 0.50-0.91, p < 0.001; ICC = 0.77, 95% CI 0.55-0.91). Bland-Altman analyses indicated a slight systematic underestimation of FDCTP Tmax maximum visible extent volumes and slight overestimation of FDCTP TTP maximum visible extent volumes compared to MDCTP. CONCLUSION FDCTP and MDCTP provide qualitatively comparable volumetric results on Tmax and TTP maps; however, direct quantitative measurements of infarct core and hypoperfused tissue volumes showed lower correlations and agreement.
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Affiliation(s)
- Bettina L Serrallach
- Department of Diagnostic and Interventional Neuroradiology, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010, Bern, Switzerland.
| | - Adnan Mujanovic
- Department of Diagnostic and Interventional Neuroradiology, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010, Bern, Switzerland
| | - Nikolaos Ntoulias
- Department of Neuroradiology, Clinic for Radiology and Nuclear Medicine, University Hospital Basel, Petersgraben 4/Spitalstrasse 21, 4031, Basel, Switzerland
| | - Michael Manhart
- Advanced Therapies, Siemens Healthcare GmbH, Siemensstrasse 1, 91301, Forchheim, Germany
| | - Mattia Branca
- CTU Bern, University of Bern, Mittelstrasse 43, 3012, Bern, Switzerland
| | - Alex Brehm
- Department of Neuroradiology, Clinic for Radiology and Nuclear Medicine, University Hospital Basel, Petersgraben 4/Spitalstrasse 21, 4031, Basel, Switzerland
| | - Marios-Nikos Psychogios
- Department of Neuroradiology, Clinic for Radiology and Nuclear Medicine, University Hospital Basel, Petersgraben 4/Spitalstrasse 21, 4031, Basel, Switzerland
| | - Christoph C Kurmann
- Department of Diagnostic and Interventional Neuroradiology, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010, Bern, Switzerland
- Graduate School for Health Sciences, University of Bern, Bern, Switzerland
- Department of Diagnostic, Interventional and Pediatric Radiology, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010, Bern, Switzerland
| | - Eike I Piechowiak
- Department of Diagnostic and Interventional Neuroradiology, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010, Bern, Switzerland
| | - Sara Pilgram-Pastor
- Department of Diagnostic and Interventional Neuroradiology, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010, Bern, Switzerland
| | - Thomas Meinel
- Department of Neurology, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010, Bern, Switzerland
| | - David Seiffge
- Department of Neurology, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010, Bern, Switzerland
| | - Pasquale Mordasini
- Department of Radiology, Netzwerk Radiologie, Kantonsspital St. Gallen, Rorschacher Strasse 95, 9007, St. Gallen, Switzerland
| | - Jan Gralla
- Department of Diagnostic and Interventional Neuroradiology, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010, Bern, Switzerland
| | - Tomas Dobrocky
- Department of Diagnostic and Interventional Neuroradiology, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010, Bern, Switzerland
| | - Johannes Kaesmacher
- Department of Diagnostic and Interventional Neuroradiology, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse, 3010, Bern, Switzerland
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2
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Alwood BT, Meyer DM, Ionita C, Snyder KV, Santos R, Perrotta L, Crooks R, Van Orden K, Torres D, Poynor B, Pham N, Kelly S, Meyer BC, Bolar DS. Multicenter comparison using two AI stroke CT perfusion software packages for determining thrombectomy eligibility. J Stroke Cerebrovasc Dis 2024; 33:107750. [PMID: 38703875 DOI: 10.1016/j.jstrokecerebrovasdis.2024.107750] [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: 10/14/2023] [Revised: 04/25/2024] [Accepted: 04/29/2024] [Indexed: 05/06/2024] Open
Abstract
BACKGROUND Stroke AI platforms assess infarcted core and potentially salvageable tissue (penumbra) to identify patients suitable for mechanical thrombectomy. Few studies have compared outputs of these platforms, and none have been multicenter or considered NIHSS or scanner/protocol differences. Our objective was to compare volume estimates and thrombectomy eligibility from two widely used CT perfusion (CTP) packages, Viz.ai and RAPID.AI, in a large multicenter cohort. METHODS We analyzed CTP data of acute stroke patients with large vessel occlusion (LVO) from four institutions. Core and penumbra volumes were estimated by each software and DEFUSE-3 thrombectomy eligibility assessed. Results between software packages were compared and categorized by NIHSS score, scanner manufacturer/model, and institution. RESULTS Primary analysis of 362 cases found statistically significant differences in both software's volume estimations, with subgroup analysis showing these differences were driven by results from a single scanner model, the Canon Aquilion One. Viz.ai provided larger estimates with mean differences of 8cc and 18cc for core and penumbra, respectively (p<0.001). NIHSS subgroup analysis also showed systematically larger Viz.ai volumes (p<0.001). Despite volume differences, a significant difference in thrombectomy eligibility was not found. Additional subgroup analysis showed significant differences in penumbra volume for the Phillips Ingenuity scanner, and thrombectomy eligibility for the Canon Aquilion One scanner at one center (7 % increased eligibility with Viz.ai, p=0.03). CONCLUSIONS Despite systematic differences in core and penumbra volume estimates between Viz.ai and RAPID.AI, DEFUSE-3 eligibility was not statistically different in primary or NIHSS subgroup analysis. A DEFUSE-3 eligibility difference, however, was seen on one scanner at one institution, suggesting scanner model and local CTP protocols can influence performance and cause discrepancies in thrombectomy eligibility. We thus recommend centers discuss optimal scanning protocols with software vendors and scanner manufacturers to maximize CTP accuracy.
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Affiliation(s)
- Benjamin T Alwood
- Department of Vascular Neurology, University of Florida, Jacksonville, FL, United States; University of California San Diego Stroke Center, University of California San Diego, San Diego, CA, United States.
| | - Dawn M Meyer
- University of California San Diego Stroke Center, University of California San Diego, San Diego, CA, United States
| | - Chip Ionita
- Department of Biomedical Engineering and Neurosurgery, University at Buffalo, Buffalo NY, United States
| | - Kenneth V Snyder
- Department of Biomedical Engineering and Neurosurgery, University at Buffalo, Buffalo NY, United States
| | - Roberta Santos
- Department of Vascular Neurology, University of Florida, Jacksonville, FL, United States
| | - Lindsey Perrotta
- Department of Vascular Neurology, University of Florida, Jacksonville, FL, United States
| | - Ryan Crooks
- Department of Vascular Neurology, University of Florida, Jacksonville, FL, United States
| | - Kimberlee Van Orden
- University of California San Diego Stroke Center, University of California San Diego, San Diego, CA, United States
| | - Dolores Torres
- University of California San Diego Stroke Center, University of California San Diego, San Diego, CA, United States
| | - Briana Poynor
- University of California San Diego Stroke Center, University of California San Diego, San Diego, CA, United States
| | - Nhan Pham
- Department of Radiology, University of California San Diego, San Diego, CA, United States
| | - Sophie Kelly
- Department of Radiology, University of California San Diego, San Diego, CA, United States
| | - Brett C Meyer
- University of California San Diego Stroke Center, University of California San Diego, San Diego, CA, United States
| | - Divya S Bolar
- Department of Radiology, University of California San Diego, San Diego, CA, United States; Center for Functional MRI, University of California San Diego, San Diego, CA, United States
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3
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Zhang H, Bao W, Yu M, Li X, Gui Y, Cui H, Zhang P. Neuroimaging Marker-CT Perfusion of Early Neurological Deterioration in Patients with Minor Stroke and Large Vessel Occlusion after Intravenous Thrombolysis. Curr Neurovasc Res 2024; 21:198-204. [PMID: 38571342 DOI: 10.2174/0115672026306424240319101049] [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: 01/22/2023] [Revised: 02/24/2024] [Accepted: 02/26/2024] [Indexed: 04/05/2024]
Abstract
OBJECTIVE Early Neurological Deterioration (END) is one of the complications in Acute ischemic stroke (AIS) and relates to prognosis. However, the reason why it occurs is still unclear. Our study is to investigate if CT perfusion (CTP) can predict END in patients with Minor Stroke and Large Vessel Occlusion after Intravenous Thrombolysis (IVT). METHODS Patients who underwent IVT with Large Vessel Occlusion were enrolled continuously from January 2021 to August 2023. After evaluating the National Institutes of Health Stroke Scale (NIHSS) score, they were divided into the END group (n=21) and the Non-END group (n=20). Multivariate logistic regression analysis was performed to explore the factors of END. Receiver-operating characteristic (ROC) curve analysis was also used to assess the discriminative ability of CTP in predicting END. RESULTS A total of 41 patients (mean age, 62.34 ± 10.82 years, 27 male) were finally included in the analysis; 21 patients had END, and 9 patients underwent Endovascular thrombectomy (EVT). Multivariate logistic regression analysis indicated that rCBV (OR=0.081, 95%CI=0.009- 0.721, p = 0.024) and admission-NIHSS (OR=1.990, 95%CI=1.049-3.772, p = 0.035) were significantly associated with END. The area under the curve (AUC) of rCBV and NIHSS to discriminate END were 0.708 and 0.758. We found patients with END had a higher modified Rankin Scale (mRS) in 3 months. CONCLUSIONS The rCBV and NIHSS were associated with post-thrombolysis END and may become reliable markers to predicate END. END might predict a poor 3-month functional outcome.
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Affiliation(s)
- Hongli Zhang
- Department of Neurology, The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, China
| | - Wanli Bao
- Department of Neurology, The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, China
| | - Meiyan Yu
- Department of Neurology, The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, China
| | - Xiang Li
- Department of Neurology, The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, China
| | - Yongkun Gui
- Department of Neurology, The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, China
| | - Hongkai Cui
- Department of Neurology, The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, China
| | - Ping Zhang
- Department of Neurology, The First Affiliated Hospital of Xinxiang Medical University, Xinxiang, China
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Lu W, Yao F, Yin C, Wan S, Liu X, He C, Leng X, Fiehler J, Siddiqui AH, Peng Y, Xiang J. Computed tomography perfusion software pipelines to assess parameter maps and ischemic volumes: A comparative study. J Neuroimaging 2023; 33:983-990. [PMID: 37737687 DOI: 10.1111/jon.13154] [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: 06/28/2023] [Revised: 08/09/2023] [Accepted: 09/06/2023] [Indexed: 09/23/2023] Open
Abstract
BACKGROUND AND PURPOSE This study was dedicated to investigating the agreement of the calculated results of two CT perfusion (CTP) postprocessing software packages, including parameter maps and ischemic volume, focusing on the infarct core volume (ICV) and penumbra volume (PV). METHODS A retrospective collection of 235 patients with acute ischemic stroke who underwent CTP examination were enrolled. All images had been analyzed with two software pipelines, RAPID CTP and AccuCTP, and the comparative analysis was based on ICV and PV results calculated by both software packages. The agreement of parameter maps was evaluated by root mean square error and Bland-Altman analysis. The ICV and PV agreement was evaluated by intraclass correlation coefficient (ICC) and Bland-Altman analysis. The accuracy of ICV and PV based on multiple thresholds was also analyzed. RESULTS The ICV and PV of AccuCTP and RAPID CTP show excellent agreement. The relative differences of the parameter maps were all within 10% and the Bland-Altman analysis also showed a strong agreement. From ordinary least squares fitting results, both ICV and PV had a remarkably high goodness of fit (ICV, R2 = 0.975 [p<.001]; PV, R2 = 0.964 [p<.001]). For the ICC analysis, both had high ICC scores (ICV ICC 0.984, 95% CI [confidence interval] 0.973-0.989; PV ICC 0.955, 95% CI 0.947-0.964). Furthermore, multi-threshold analysis on the basis of ICV and PV also achieved reliable analytical accuracy. CONCLUSIONS The image analysis results of AccuCTP are in excellent agreement with RAPID CTP and can be used as an alternative analysis tool to RAPID CTP software in stroke clinical practice.
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Affiliation(s)
- Wei Lu
- ArteryFlow Technology Co., Ltd., Hangzhou, China
| | - Feirong Yao
- Department of Radiology, The First Affiliated Hospital of Soochow University, Suzhou, China
| | - Congguo Yin
- Department of Neurology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Shu Wan
- Brain Center, Affiliated Zhejiang Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xin Liu
- ArteryFlow Technology Co., Ltd., Hangzhou, China
| | - Chongxin He
- Department of Neurosurgery, The Third People's Hospital of Hefei, Hefei, China
| | | | - Jens Fiehler
- Department of Diagnostic and Interventional Neuroradiology, University Medical Center, Hamburg-Eppendorf, Germany
| | - Adnan H Siddiqui
- Departments of Neurosurgery and Radiology, University at Buffalo, Buffalo, New York, USA
| | - Ya Peng
- Department of Neurosurgery, The First People's Hospital of Changzhou/The Third Affiliated Hospital of Soochow University, Changzhou, China
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5
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Zhang Y, Song S, Li Z, Huang B, Geng Y, Zhang L. The Application of Software "Rapid Processing of Perfusion and Diffusion" in Acute Ischemic Stroke. Brain Sci 2022; 12:1451. [PMID: 36358379 PMCID: PMC9688896 DOI: 10.3390/brainsci12111451] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 10/20/2022] [Accepted: 10/20/2022] [Indexed: 08/30/2023] Open
Abstract
In the event of an acute ischemic stroke, saving the penumbra is the most important aspect of early treatment. The rapid and accurate identification of ischemic penumbra plays a key role in its comprehensive treatment. At present, the identification method and evaluation standard of ischemic penumbra have not been unified. Numerous pieces of software identifying ischemic penumbra have been developed, such as rapid processing of perfusion and diffusion (RAPID), Sphere, Vitrea, and computed tomography perfusion+ (CTP+). The RAPID software, analyzing and integrating multi-mode image data (mainly based on perfusion weighted imaging (PWI) or computed tomography perfusion (CTP) images, shows good performance in identifying ischemic penumbra and has been utilized for the assessment of ischemic penumbra in many ischemic stroke clinical studies, achieving good outcomes and promoting the transition from "time window" to "tissue window" in the treatment of early stage AIS. To obtain a comprehensive understanding of the RAPID software and its accuracy in evaluating ischemic penumbra, this paper reviews the background and development of the RAPID software, summarizes the published acute cerebral infarction trials using the RAPID software, generalizes the threshold parameters in different time windows, and further discusses its application and limitations.
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Affiliation(s)
- Yudi Zhang
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Shuang Song
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Zhenzhong Li
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Boyuan Huang
- Department of Radiology, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
| | - Yanlu Geng
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
- Department of Neurology, Central Hospital of Qinghe County, Xingtai 054800, China
| | - Lihong Zhang
- Department of Neurology, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, China
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Kremenova K, Lukavsky J, Holesta M, Peisker T, Lauer D, Weichet J, Malikova H. CT Brain Perfusion in the Prediction of Final Infarct Volume: A Prospective Study of Different Software Settings for Acute Ischemic Core Calculation. Diagnostics (Basel) 2022; 12:diagnostics12102290. [PMID: 36291979 PMCID: PMC9601142 DOI: 10.3390/diagnostics12102290] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 09/14/2022] [Accepted: 09/19/2022] [Indexed: 11/16/2022] Open
Abstract
CT perfusion (CTP) is used for the evaluation of brain tissue viability in patients with acute ischemic stroke (AIS). We studied the accuracy of three different syngo.via software (SW) settings for acute ischemic core estimation in predicting the final infarct volume (FIV). The ischemic core was defined as follows: Setting A: an area with cerebral blood flow (CBF) < 30% compared to the contralateral healthy hemisphere. Setting B: CBF < 20% compared to contralateral hemisphere. Setting C: area of cerebral blood volume (CBV) < 1.2 mL/100 mL. We studied 47 AIS patients (aged 68 ± 11.2 years) with large vessel occlusion in the anterior circulation, treated in the early time window (up to 6 h), who underwent technically successful endovascular thrombectomy (EVT). FIV was measured on MRI performed 24 ± 2 h after EVT. In general, all three settings correlated with each other; however, the absolute agreement between acute ischemic core volume on CTP and FIV on MRI was poor; intraclass correlation for all three settings was between 0.64 and 0.69, root mean square error of the individual observations was between 58.9 and 66.0. Our results suggest that using CTP syngo.via SW for prediction of FIV in AIS patients in the early time window is not appropriate.
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Affiliation(s)
- Karin Kremenova
- Radiology Department, Third Faculty of Medicine, Charles University, Faculty Hospital Kralovske Vinohrady, 100 34 Prague, Czech Republic
- Correspondence:
| | - Jiri Lukavsky
- Institute of Psychology, Czech Academy of Sciences, 110 00 Prague, Czech Republic
| | - Michal Holesta
- Radiology Department, Third Faculty of Medicine, Charles University, Faculty Hospital Kralovske Vinohrady, 100 34 Prague, Czech Republic
| | - Tomas Peisker
- Neurology Department, Third Faculty of Medicine, Charles University, Faculty Hospital Kralovske Vinohrady, 100 34 Prague, Czech Republic
| | - David Lauer
- Neurology Department, Third Faculty of Medicine, Charles University, Faculty Hospital Kralovske Vinohrady, 100 34 Prague, Czech Republic
| | - Jiri Weichet
- Radiology Department, Third Faculty of Medicine, Charles University, Faculty Hospital Kralovske Vinohrady, 100 34 Prague, Czech Republic
| | - Hana Malikova
- Radiology Department, Third Faculty of Medicine, Charles University, Faculty Hospital Kralovske Vinohrady, 100 34 Prague, Czech Republic
- Institute of Anatomy, Second Faculty of Medicine, Charles University, 150 00 Prague, Czech Republic
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Chalet L, Boutelier T, Christen T, Raguenes D, Debatisse J, Eker OF, Becker G, Nighoghossian N, Cho TH, Canet-Soulas E, Mechtouff L. Clinical Imaging of the Penumbra in Ischemic Stroke: From the Concept to the Era of Mechanical Thrombectomy. Front Cardiovasc Med 2022; 9:861913. [PMID: 35355966 PMCID: PMC8959629 DOI: 10.3389/fcvm.2022.861913] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2022] [Accepted: 02/11/2022] [Indexed: 01/01/2023] Open
Abstract
The ischemic penumbra is defined as the severely hypoperfused, functionally impaired, at-risk but not yet infarcted tissue that will be progressively recruited into the infarct core. Early reperfusion aims to save the ischemic penumbra by preventing infarct core expansion and is the mainstay of acute ischemic stroke therapy. Intravenous thrombolysis and mechanical thrombectomy for selected patients with large vessel occlusion has been shown to improve functional outcome. Given the varying speed of infarct core progression among individuals, a therapeutic window tailored to each patient has recently been proposed. Recent studies have demonstrated that reperfusion therapies are beneficial in patients with a persistent ischemic penumbra, beyond conventional time windows. As a result, mapping the penumbra has become crucial in emergency settings for guiding personalized therapy. The penumbra was first characterized as an area with a reduced cerebral blood flow, increased oxygen extraction fraction and preserved cerebral metabolic rate of oxygen using positron emission tomography (PET) with radiolabeled O2. Because this imaging method is not feasible in an acute clinical setting, the magnetic resonance imaging (MRI) mismatch between perfusion-weighted imaging and diffusion-weighted imaging, as well as computed tomography perfusion have been proposed as surrogate markers to identify the penumbra in acute ischemic stroke patients. Transversal studies comparing PET and MRI or using longitudinal assessment of a limited sample of patients have been used to define perfusion thresholds. However, in the era of mechanical thrombectomy, these thresholds are debatable. Using various MRI methods, the original penumbra definition has recently gained a significant interest. The aim of this review is to provide an overview of the evolution of the ischemic penumbra imaging methods, including their respective strengths and limitations, as well as to map the current intellectual structure of the field using bibliometric analysis and explore future directions.
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Affiliation(s)
- Lucie Chalet
- Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, Lyon, France
- Olea Medical, La Ciotat, France
| | | | - Thomas Christen
- Grenoble Institut Neurosciences, INSERM, U1216, Univ. Grenoble Alpes, Grenoble, France
| | | | - Justine Debatisse
- Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, Lyon, France
| | - Omer Faruk Eker
- CREATIS, CNRS UMR-5220, INSERM U1206, Université Lyon 1, Villeurbanne, France
- Neuroradiology Department, Hospices Civils of Lyon, Lyon, France
| | - Guillaume Becker
- Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, Lyon, France
| | - Norbert Nighoghossian
- Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, Lyon, France
- Stroke Department, Hospices Civils of Lyon, Lyon, France
| | - Tae-Hee Cho
- Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, Lyon, France
- Stroke Department, Hospices Civils of Lyon, Lyon, France
| | - Emmanuelle Canet-Soulas
- Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, Lyon, France
| | - Laura Mechtouff
- Univ Lyon, CarMeN Laboratory, INSERM, INRA, INSA Lyon, Université Claude Bernard Lyon 1, Lyon, France
- Stroke Department, Hospices Civils of Lyon, Lyon, France
- *Correspondence: Laura Mechtouff
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