Penumbral Imaging by Using Perfusion Computed Tomography and Perfusion-Weighted Magnetic Resonance Imaging: Current Concepts

doi:10.1016/j.jstrokecerebrovasdis.2012.10.002

Journal of Stroke and Cerebrovascular Diseases

Volume 22, Issue 8, November 2013, Pages 1212-1215

https://doi.org/10.1016/j.jstrokecerebrovasdis.2012.10.002 Get rights and content

Perfusion computed tomography and perfusion-weighted magnetic resonance imaging are used to evaluate the extent of the area with ischemic penumbra; however, different parameters, algorithms, and software packages show significant discrepancies in the size of perfusion abnormalities, which should be minimized. Recently, cross-validation studies were performed using digital phantoms and have elucidated the precision and reliability of various penumbral imaging techniques. These research initiatives can promote further multicenter trials on recanalization therapies by providing accurate inclusion/exclusion criteria for appropriate patient selection.

Section snippets

Basic Concepts and Technical Issues of Penumbral Imaging

In both PCT and PWI, temporal changes in density or signal of brain tissue on dynamic imaging is measured during bolus intravenous administration of contrast agents, and many perfusion parameters are generated from the serial dataset using an intravascular tracer model with various algorithms.² According to the mismatch concept, ischemic penumbra is shown as a zone between the outer border of the infarct core and that of the penumbral area; that is, a discrepancy between predicted final

References (14)

W. Hacke et al.
Intravenous desmoteplase in patients with acute ischaemic stroke selected by MRI perfusion-diffusion weighted imaging or perfusion CT (DIAS-2): a prospective, randomised, double-blind, placebo-controlled study
Lancet Neurol
(2009)
S.M. Davis et al.
Effects of alteplase beyond 3h after stroke in the Echoplanar Imaging Thrombolytic Evaluation Trial (Epithet): a placebo-controlled randomised trial
Lancet Neurol
(2008)
P.D. Schellinger et al.
Evidence-based guideline: the role of diffusion and perfusion MRI for the diagnosis of acute ischemic stroke
Neurology
(2010)
C. Leiva-Salinas et al.
The alphabet soup of perfusion CT and MR imaging: terminology revisited and clarified in five questions
Neuroradiology
(2012)
I. Kane et al.
Comparison of 10 different magnetic resonance perfusion imaging processing methods in acute ischemic stroke: Effect on lesion size, proportion of patients with diffusion/perfusion mismatch, clinical scores, and radiologic outcomes
Stroke
(2007)
M. Sasaki et al.
Tracer delay-insensitive algorithm can improve reliability of CT perfusion imaging for cerebrovascular steno-occlusive disease: comparison with quantitative single-photon emission CT
Am J Neuroradiol
(2009)
K. Kudo et al.
Differences in CT perfusion maps generated by different commercial software: quantitative analysis by using identical source data of acute stroke patients
Radiology
(2010)

There are more references available in the full text version of this article.

Cited by (7)

Large Vessel Occlusion Sites Affect Agreement Between Outputs of Three Computed Tomography Perfusion Software Packages
2022, Journal of Stroke and Cerebrovascular Diseases
Citation Excerpt :
Different vendors have developed proprietary CTP processing software packages over the last 20 years.7 Significant variability in penumbra and infarct core predictions exists among these software packages and standardization remains elusive.8–17 Recent studies comparing CTP outputs have focused on specific subgroups of AIS patients with large vessel occlusion (LVO) and showed software non-inferiority to RAPID using final infarct volume as determined by follow up magnetic resonance imaging (MRI).11–14
Computed tomography perfusion (CTP) data are important for hyperacute stroke decision making. Available comparisons between outputs of different CTP software packages show variable outcomes. Evaluation for factors associated with agreement between the volume estimates is limited. We assessed for differences in core and penumbra volume estimates of three CTP software packages – AutoMIStar, RAPID, and Vitrea – and analyzed factors associated with agreement between the volume estimates.
Differences between software estimates of penumbra and core volumes were calculated for each patient with suspected acute ischemic stroke who underwent CTP. Exploratory hierarchical clustering and principal component analysis were performed to identify factors of decreased volume estimate agreement. Two-sample t-tests were performed, stratified by large vessel occlusion (LVO) location.
579 CTP studies were performed; 267 were normal, 139 artifacts, with 172 included in the final analysis. 79/172 had LVO of internal carotid artery (ICA, n = 20), M1 (n = 38) and proximal M2 (n = 21). LVO was the only factor associated with decreased software package agreement, and proximal LVO location was associated with general trend of increasing mean differences and standard deviations between software packages (range of mean differences [SD]: non-LVO, -17–6 [4–33] ml; M2, -40–13 [5–39] ml; M1, -43–26 [16–58] ml; ICA, -76–39 [22–97] ml).
Core and penumbra volume estimates can be affected by LVO location significantly between CTP software packages.
NADPH oxidase-related pathophysiology in experimental models of stroke
2017, International Journal of Molecular Sciences
A 4D CT digital phantom of an individual human brain for perfusion analysis
2016, PeerJ
Evaluation of cerebral perfusion in patients undergoing intravenous recombinant tissue plasminogen activator thrombolysis
2015, Neurologia Medico-Chirurgica
Predicting cerebral hyperperfusion syndrome following superficial temporal artery to middle cerebral artery bypass based on intraoperative perfusion-weighted magnetic resonance imaging
2015, Scientific Reports
ASFNR recommendations for clinical performance of MR dynamic susceptibility contrast perfusion imaging of the brain
2015, American Journal of Neuroradiology

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: This work was supported in part by a Grant-in-Aid for Strategic Medical Science Research Center from the Ministry of Education, Culture, Sports, Science and Technology of Japan.

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Review ArticlePenumbral Imaging by Using Perfusion Computed Tomography and Perfusion-Weighted Magnetic Resonance Imaging: Current Concepts

Section snippets

Basic Concepts and Technical Issues of Penumbral Imaging

Lancet Neurol

Lancet Neurol

Evidence-based guideline: the role of diffusion and perfusion MRI for the diagnosis of acute ischemic stroke

Neurology

The alphabet soup of perfusion CT and MR imaging: terminology revisited and clarified in five questions

Neuroradiology

Comparison of 10 different magnetic resonance perfusion imaging processing methods in acute ischemic stroke: Effect on lesion size, proportion of patients with diffusion/perfusion mismatch, clinical scores, and radiologic outcomes

Stroke

Tracer delay-insensitive algorithm can improve reliability of CT perfusion imaging for cerebrovascular steno-occlusive disease: comparison with quantitative single-photon emission CT

Am J Neuroradiol

Differences in CT perfusion maps generated by different commercial software: quantitative analysis by using identical source data of acute stroke patients

Radiology

Review Article
Penumbral Imaging by Using Perfusion Computed Tomography and Perfusion-Weighted Magnetic Resonance Imaging: Current Concepts