Search

Your search keyword '"Wermer, M. J."' showing total 117 results
Start Over Author "Wermer, M. J."
117 results on '"Wermer, M. J."'

2. Minocycline for sporadic and hereditary cerebral amyloid angiopathy (BATMAN): study protocol for a placebo-controlled randomized double-blind trial

Author

Voigt, S., primary, Koemans, E. A., additional, Rasing, I., additional, van Etten, E. S., additional, Terwindt, G. M., additional, Baas, F., additional, Kaushik, K., additional, van Es, A. C. G. M., additional, van Buchem, M. A., additional, van Osch, M. J. P., additional, van Walderveen, M. A. A., additional, Klijn, C. J. M., additional, Verbeek, M. M., additional, van der Weerd, L., additional, and Wermer, M. J. H., additional

Published
2023
Full Text
View/download PDF

4. Additional file 1 of Minocycline for sporadic and hereditary cerebral amyloid angiopathy (BATMAN): study protocol for a placebo-controlled randomized double-blind trial

Author

Voigt, S., Koemans, E. A., Rasing, I., van Etten, E. S., Terwindt, G. M., Baas, F., Kaushik, K., van Es, A. C. G. M., van Buchem, M. A., van Osch, M. J. P., van Walderveen, M. A. A., Klijn, C. J. M., Verbeek, M. M., van der Weerd, L., and Wermer, M. J. H.

Abstract

Additional file 1: Supplementary Table 1. BATMANR1.

Published
2023
Full Text
View/download PDF

5. Systematic Review - Combining Neuroprotection With Reperfusion in Acute Ischemic Stroke

Author

Vos, E. M., Geraedts, V. J., van der Lugt, A., Dippel, D. W. J., Wermer, M. J. H., Hofmeijer, J., van Es, A. C. G. M., Roos, Y. B. W. E. M., Peeters-Scholte, C. M. P. C. D., van den Wijngaard, I. R., Vos, E. M., Geraedts, V. J., van der Lugt, A., Dippel, D. W. J., Wermer, M. J. H., Hofmeijer, J., van Es, A. C. G. M., Roos, Y. B. W. E. M., Peeters-Scholte, C. M. P. C. D., and van den Wijngaard, I. R.

Abstract

Background: Clinical trials of neuroprotection in acute ischemic stroke (AIS) have provided disappointing results. Reperfusion may be a necessary condition for positive effects of neuroprotective treatments. This systematic review provides an overview of efficacy of neuroprotective agents in combination with reperfusion therapy in AIS. Methods: A literature search was performed on the following databases, namely PubMed, Embase, Web of Science, Cochrane Library, Emcare. All databases were searched up to September 23rd 2021. All randomized controlled trials in which patients were treated with neuroprotective strategies within 12 h of stroke onset in combination with intravenous thrombolysis (IVT), endovascular therapy (EVT), or both were included. Results: We screened 1,764 titles/abstracts and included 30 full reports of unique studies with a total of 16,160 patients. In 15 studies neuroprotectants were tested for clinical efficacy, where all patients had to receive reperfusion therapies, either IVT and/or EVT. Heterogeneity in reported outcome measures was observed. Treatment was associated with improved clinical outcome for: 1) uric acid in patients treated with EVT and IVT, 2) nerinetide in patients who underwent EVT without IVT, 3) imatinib in stroke patients treated with IVT with or without EVT, 4) remote ischemic perconditioning and IVT, and 5) high-flow normobaric oxygen treatment after EVT, with or without IVT. Conclusion: Studies specifically testing effects of neuroprotective agents in addition to IVT and/or EVT are scarce. Future neuroprotection studies should report standardized functional outcome measures and combine neuroprotective agents with reperfusion therapies in AIS or aim to include prespecified subgroup analyses for treatment with IVT and/or EVT.

Published
2022

6. The prognostic value of extracranial vascular characteristics on procedural duration and revascularization success in endovascularly treated acute ischemic stroke patients

Author

Holswilder, G., Stuart, M. P. M. E., Dompeling, T., Kruyt, N. D., Goeman, J. J., van der Lugt, A., Schonewille, W. J., Lycklama à Nijeholt, G. J., Majoie, C. B. L. M., Yo, L. S. F., Meijer, F. J. A., Marquering, H. A., Wermer, M. J. H., van Walderveen, M. A. A., Holswilder, G., Stuart, M. P. M. E., Dompeling, T., Kruyt, N. D., Goeman, J. J., van der Lugt, A., Schonewille, W. J., Lycklama à Nijeholt, G. J., Majoie, C. B. L. M., Yo, L. S. F., Meijer, F. J. A., Marquering, H. A., Wermer, M. J. H., and van Walderveen, M. A. A.

Abstract

Introduction: Vascular anatomy might affect endovascular treatment success in acute ischemic stroke patients with large vessel occlusion. We investigated the prognostic value of extracranial vascular characteristics on procedural time and revascularization success in patients with large vessel occlusion in the anterior cerebral circulation. Patients and methods: We included 828 patients endovascularly treated within 6.5 hours of symptom onset from the Dutch MR CLEAN-Registry. We evaluated aortic arch configuration, stenosis and tortuosity of supra-aortic arteries, and internal carotid arteries (ICAs) on pre-intervention CTA. We constructed logistic prediction models for outcome variables procedural duration (≥60 minutes) and non-successful revascularization (extended thrombolysis in cerebral infarction (eTICI) of 0–2A) using baseline characteristics and assessed the effect of extracranial vascular characteristics on model performance. Results: Cervical ICA tortuosity and stenosis ≥99% improved prediction of long procedural duration compared with baseline characteristics from area under the curve of 0.61 (95% CI: 0.57–0.65) to 0.66 (95% CI: 0.62–0.70) (P < 0.001). Cervical ICA tortuosity was significantly associated with non-successful recanalization. Prediction of non-successful revascularization did not improve after including aortic arch elongation, acute take-off angle, aortic variant, origin stenosis of supra-aortic arteries, and cervical ICA tortuosity, with an area under the curve of 0.63 (95% CI: 0.59–0.67) compared with 0.59 (95% CI: 0.55–0.63) (P = 0.11). Conclusion: Extracranial vascular characteristics have additional prognostic value for procedural duration, but not for revascularization success, compared with baseline characteristics. Performance of both prediction models is limited in patients treated for large vessel occlusion.

Published
2022

14. Intracranial Cerebrospinal Fluid Volume as a Predictor of Malignant Middle Cerebral Artery Infarction

Author

Kauw, Frans, Bennink, Edwin, de Jong, Hugo W. A. M., Kappelle, L. Jaap, Horsch, Alexander D., Velthuis, Birgitta K., Dankbaar, Jan W., Majoie, C. B., Roos, Y. B., Duijm, L. E., Keizer, K., van der Lugt, A., Dippel, D. W., Droogh-de Greve, K. E., Bienfait, H. P., van Walderveen, M. A., Wermer, M. J., Nijeholt, Lycklama A. G. J., Boiten, J., Duyndam, D., Kwa, V., I, Meijer, F. J., van Dijk, E. J., Kesselring, F. O., Hofmeijer, J., Vos, J. A., Schonewille, W. J., van Rooij, W. J., de Kort, P. L., Pleiter, C. C., Bakker, S. L., Bot, J., Visser, M. C., Velthuis, B. K., van der Schaaf, I. C., Dankbaar, J. W., Mali, W. P., van Seeters, T., Horsch, A. D., Niesten, J. M., Biessels, G. J., Kappelle, L. J., Luitse, M. J., van der Graaf, Y., Radiology & Nuclear Medicine, Neurology, Physics and medical technology, Radiology and nuclear medicine, VU University medical center, Dermatology, Surgery, Public and occupational health, Human genetics, Radiation Oncology, Amsterdam Neuroscience - Neurovascular Disorders, and ACS - Atherosclerosis & ischemic syndromes

Subjects
medicine.medical_specialty, Original Contributions, infarction, Clinical Sciences, Clinical Neurology, Infarction, Perfusion scanning, All institutes and research themes of the Radboud University Medical Center, Midline shift, Internal medicine, medicine.artery, Journal Article, Medicine, odds ratio, cardiovascular diseases, Advanced and Specialised Nursing, humans, Stroke, Advanced and Specialized Nursing, brain edema, middle cerebral artery, infarction, middle cerebral artery, Receiver operating characteristic, medicine.diagnostic_test, business.industry, Odds ratio, medicine.disease, Disorders of movement Donders Center for Medical Neuroscience [Radboudumc 3], Angiography, Middle cerebral artery, Cardiology, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, Neurology (clinical), prognosis, business, Cardiology and Cardiovascular Medicine, Rare cancers Radboud Institute for Health Sciences [Radboudumc 9]
Abstract

Supplemental Digital Content is available in the text., Background and Purpose— Predicting malignant middle cerebral artery (MCA) infarction can help to identify patients who may benefit from preventive decompressive surgery. We aimed to investigate the association between the ratio of intracranial cerebrospinal fluid (CSF) volume to intracranial volume (ICV) and malignant MCA infarction. Methods— Patients with an occlusion proximal to the M3 segment of the MCA were selected from the DUST (Dutch Acute Stroke Study). Admission imaging included noncontrast computed tomography (CT), CT perfusion, and CT angiography. Patient characteristics and CT findings were collected. The ratio of intracranial CSF volume to ICV (CSF/ICV) was quantified on admission thin-slice noncontrast CT. Malignant MCA infarction was defined as a midline shift of >5 mm on follow-up noncontrast CT, which was performed 3 days after the stroke or in case of clinical deterioration. To test the association between CSF/ICV and malignant MCA infarction, odds ratios and 95% CIs were calculated for 3 multivariable models by using binary logistic regression. Model performances were compared by using the likelihood ratio test. Results— Of the 286 included patients, 35 (12%) developed malignant MCA infarction. CSF/ICV was independently associated with malignant MCA infarction in 3 multivariable models: (1) with age and admission National Institutes of Health Stroke Scale (odds ratio, 3.3; 95% CI, 1.1–11.1), (2) with admission National Institutes of Health Stroke Scale and poor collateral score (odds ratio, 7.0; 95% CI, 2.6–21.3), and (3) with terminal internal carotid artery or proximal M1 occlusion and poor collateral score (odds ratio, 7.7; 95% CI, 2.8–23.9). The performance of model 1 (areas under the receiver operating characteristic curves, 0.795 versus 0.824; P=0.033), model 2 (areas under the receiver operating characteristic curves, 0.813 versus 0.850; P

Published
2019

17. Data-efficient deep learning of radiological image data for outcome prediction after endovascular treatment of patients with acute ischemic stroke

Author

Hilbert, A., Ramos, L. A., van Os, H. J. A., Olabarriaga, S. D., Tolhuisen, M. L., Wermer, M. J. H., Barros, R. S., van der Schaaf, I., Dippel, D., Roos, Y. B. W. E. M., van Zwam, W. H., Yoo, A. J., Emmer, B. J., Nijeholt, G. J. Lycklama a, Zwinderman, A. H., Strijkers, G. J., Majoie, C. B. L. M., Marquering, H. A., Hilbert, A., Ramos, L. A., van Os, H. J. A., Olabarriaga, S. D., Tolhuisen, M. L., Wermer, M. J. H., Barros, R. S., van der Schaaf, I., Dippel, D., Roos, Y. B. W. E. M., van Zwam, W. H., Yoo, A. J., Emmer, B. J., Nijeholt, G. J. Lycklama a, Zwinderman, A. H., Strijkers, G. J., Majoie, C. B. L. M., and Marquering, H. A.

Abstract

Treatment selection is becoming increasingly more important in acute ischemic stroke patient care. Clinical variables and radiological image biomarkers (old age, pre-stroke mRS, NIHSS, occlusion location, ASPECTS, among others) have an important role in treatment selection and prognosis. Radiological biomarkers require expert annotation and are subject to inter-observer variability. Recently, Deep Learning has been introduced to reproduce these radiological image biomarkers. Instead of reproducing these biomarkers, in this work, we investigated Deep Learning techniques for building models to directly predict good reperfusion after endovascular treatment (EVT) and good functional outcome using CT angiography images. These models do not require image annotation and are fast to compute. We compare the Deep Learning models to Machine Learning models using traditional radiological image biomarkers. We explored Residual Neural Network (ResNet) architectures, adapted them with Structured Receptive Fields (RFNN) and auto-encoders (AE) for network weight initialization. We further included model visualization techniques to provide insight into the network's decision-making process. We applied the methods on the MR CLEAN Registry dataset with 1301 patients. The Deep Learning models outperformed the models using traditional radiological image biomarkers in three out of four cross-validation folds for functional outcome (average AUC of 0.71) and for all folds for reperfusion (average AUC of 0.65). Model visualization showed that the arteries were relevant features for functional outcome prediction. The best results were obtained for the ResNet models with RFNN. Auto-encoder initialization often improved the results. We concluded that, in our dataset, automated image analysis with Deep Learning methods outperforms radiological image biomarkers for stroke outcome prediction and has the potential to improve treatment selection.

Published
2019

18. Variation in arterial input function in a large multicenter computed tomography perfusion study.

Author

Peerlings, Daan, Bennink, Edwin, Dankbaar, Jan W., Velthuis, Birgitta K., de Jong, Hugo W. A. M., On behalf of the DUtch acute STroke (DUST) study investigators, Majoie, C. B., Roos, Y. B., Duijm, L. E., Keizer, K., van der Lugt, A., Dippel, D. W., Droogh - de Greeve, K. E., Bienfait, H. P., van Walderveen, M. A., Wermer, M. J., Lycklama à Nijeholt, G. J., Boiten, J., Duyndam, D., and Kwa, V. I.

Subjects
COMPUTED tomography, PERFUSION imaging, CONTRAST media, STROKE, SINGULAR value decomposition, PERFUSION
Abstract

Objectives: To report the variation in computed tomography perfusion (CTP) arterial input function (AIF) in a multicenter stroke study and to assess the impact this has on CTP results. Methods: CTP datasets from 14 different centers were included from the DUtch acute STroke (DUST) study. The AIF was taken as a direct measure to characterize contrast bolus injection. Statistical analysis was applied to evaluate differences in amplitude, area under the curve (AUC), bolus arrival time (BAT), and time to peak (TTP). To assess the clinical relevance of differences in AIF, CTP acquisitions were simulated with a realistic anthropomorphic digital phantom. Perfusion parameters were extracted by CTP analysis using commercial software (IntelliSpace Portal (ISP), version 10.1) as well as an in-house method based on block-circulant singular value decomposition (bSVD). Results: A total of 1422 CTP datasets were included, ranging from 6 to 322 included patients per center. The measured values of the parameters used to characterize the AIF differed significantly with approximate interquartile ranges of 200–750 HU for the amplitude, 2500–10,000 HU·s for the AUC, 0–17 s for the BAT, and 10–26 s for the TTP. Mean infarct volumes of the phantom were significantly different between centers for both methods of perfusion analysis. Conclusions: Although guidelines for the acquisition protocol are often provided for centers participating in a multicenter study, contrast medium injection protocols still vary. The resulting volumetric differences in infarct core and penumbra may impact clinical decision making in stroke diagnosis. Key Points: • The contrast medium injection protocol may be different between stroke centers participating in a harmonized multicenter study. • The contrast medium injection protocol influences the results of X-ray computed tomography perfusion imaging. • The contrast medium injection protocol can impact stroke diagnosis and patient selection for treatment. [ABSTRACT FROM AUTHOR]

Published
2021
Full Text
View/download PDF

19. Predicting the presence of macrovascular causes in non-traumatic intracerebral haemorrhage: the DIAGRAM prediction score

Author

Hilkens, Nina A., van Asch, Charlotte J. J., Werring, David J., Wilson, Duncan, Rinkel, Gabriël J. E., Algra, Ale, Velthuis, Birgitta K., de Kort, G. rard A. P., Witkamp, Theo D., van Nieuwenhuizen, Koen M., de Leeuw, Frank-Erik, Schonewille, Wouter J., de Kort, Paul L. M., Dippel, Diederik W. J., Raaymakers, Theodora W. M., Hofmeijer, Jeannette, Wermer, Marieke J. H., Kerkhoff, Henk, Jellema, Korné, Bronner, Irene M., Remmers, Michel J. M., Bienfait, Henri Paul, Witjes, Ron J. G. M., Jäger, H. Rolf, Greving, Jacoba P., Klijn, Catharina J. M., Boogaarts, H. B., van Dijk, E. J., Schonewille, W. J., Pellikaan, W. M. J., Puppels-de Waard, C., de Kort, P. L. M., Peluso, J. P., van Tuijl, J. H., Hofmeijer, J., Joosten, F. B. M., Dippel, D. W., Khajeh, L., Raaijmakers, T. W. M., Wermer, M. J., van Walderveen, M. A., Kerkhoff, H., Zock, E., Jellema, K., Lycklama, G. J., Bronner, I. M., Remmers, M. J. M., Witjes, R. J. G. M., Bienfait, H. P., Droogh-Greve, K. E., Donders, R. C. J. M., Kwa, V. I. H., Schreuder, T. H., Franke, C. L., Straver, J. S., Jansen, C., Bakker, S. L. M., Pleiter, C. C., Visser, M. C., van Asch, C. J. J., Velthuis, B. K., Rinkel, G. J. E., van Nieuwenhuizen, K. M., Klijn, C. J. M., Neurology, and Amsterdam Neuroscience - Neurovascular Disorders

Subjects
Adult, Male, medicine.medical_specialty, Adolescent, Computed Tomography Angiography, Clinical Neurology, Logistic regression, Magnetic resonance angiography, 03 medical and health sciences, Young Adult, 0302 clinical medicine, All institutes and research themes of the Radboud University Medical Center, Predictive Value of Tests, Risk Factors, Internal medicine, Non traumatic, medicine, Humans, 030212 general & internal medicine, cardiovascular diseases, Prospective Studies, Aged, Cerebral Hemorrhage, Netherlands, Central Nervous System Vascular Malformations, Prediction score, medicine.diagnostic_test, business.industry, Arteriovenous malformation, Digital subtraction angiography, Middle Aged, medicine.disease, Disorders of movement Donders Center for Medical Neuroscience [Radboudumc 3], nervous system diseases, Cerebral Angiography, Psychiatry and Mental health, Logistic Models, Cohort, Angiography, Cardiology, Surgery, Female, Neurology (clinical), business, 030217 neurology & neurosurgery, Magnetic Resonance Angiography
Abstract

ObjectiveA substantial part of non-traumatic intracerebral haemorrhages (ICH) arises from a macrovascular cause, but there is little guidance on selection of patients for additional diagnostic work-up. We aimed to develop and externally validate a model for predicting the probability of a macrovascular cause in patients with non-traumatic ICH.MethodsThe DIagnostic AngioGRAphy to find vascular Malformations (DIAGRAM) study (n=298; 69 macrovascular cause; 23%) is a prospective, multicentre study assessing yield and accuracy of CT angiography (CTA), MRI/ magnetic resonance angiography (MRA) and intra-arterial catheter angiography in diagnosing macrovascular causes in patients with non-traumatic ICH. We considered prespecified patient and ICH characteristics in multivariable logistic regression analyses as predictors for a macrovascular cause. We combined independent predictors in a model, which we validated in an external cohort of 173 patients with ICH (78 macrovascular cause, 45%).ResultsIndependent predictors were younger age, lobar or posterior fossa (vs deep) location of ICH, and absence of small vessel disease (SVD). A model that combined these predictors showed good performance in the development data (c-statistic 0.83; 95% CI 0.78 to 0.88) and moderate performance in external validation (c-statistic 0.66; 95% CI 0.58 to 0.74). When CTA results were added, the c-statistic was excellent (0.91; 95% CI 0.88 to 0.94) and good after external validation (0.88; 95% CI 0.83 to 0.94). Predicted probabilities varied from 1% in patients aged 51–70 years with deep ICH and SVD, to more than 50% in patients aged 18–50 years with lobar or posterior fossa ICH without SVD.ConclusionThe DIAGRAM scores help to predict the probability of a macrovascular cause in patients with non-traumatic ICH based on age, ICH location, SVD and CTA.

Published
2017

21. Dutch Parelsnoer Institute-Cerebrovascular Accident (CVA) Study: A Large Multicenter Clinical Biobank with Standardized Collection and Storage

Author

Van Os, H. J. A., primary, Ruigrok, Y. M., additional, Manniën, J., additional, Van Dijk, E. J., additional, Koudstaal, P. J., additional, Luijckx, G. J., additional, Nederkoorn, P. J., additional, Van Oostenbrugge, R. J., additional, Visser, M. C., additional, Kappelle, L. J., additional, Verspaget, H. W., additional, Algra, A., additional, and Wermer, M. J. H., additional

Published
2018
Full Text
View/download PDF

24. Temporal profile of body temperature in acute ischemic stroke : Relation to infarct size and outcome

Author

Geurts, Marjolein, Scheijmans, Féline E V, van Seeters, Tom, Biessels, Geert J., Kappelle, L. Jaap, Velthuis, Birgitta K., van der Worp, H. Bart, Majoie, C. B., Roos, Y. B., Duijm, L. E., Keizer, K., van der Lugt, A., Dippel, D. W., Greve, Droogh de, Bienfait, H. P., van Walderveen, M. A., Wermer, M. J., Lycklama à Nijeholt, G. J., Boiten, J., Duyndam, D., Kwa, V. I., Meijer, F. J., van Dijk, E. J., Kesselring, F. O., Hofmeijer, J., Vos, J. A., Schonewille, W. J., van Rooij, W. J., de Kort, P. L., Pleiter, C. C., Bakker, S. L., Bot, J., Visser, M. C., Velthuis, B. K., van der Schaaf, I. C., Dankbaar, J. W., Mali, W. P., van Seeters, T., Horsch, A. D., Niesten, J. M., Biessels, G. J., Kappelle, L. J., Luitse, M. J., van der Graaf, Y., Geurts, Marjolein, Scheijmans, Féline E V, van Seeters, Tom, Biessels, Geert J., Kappelle, L. Jaap, Velthuis, Birgitta K., van der Worp, H. Bart, Majoie, C. B., Roos, Y. B., Duijm, L. E., Keizer, K., van der Lugt, A., Dippel, D. W., Greve, Droogh de, Bienfait, H. P., van Walderveen, M. A., Wermer, M. J., Lycklama à Nijeholt, G. J., Boiten, J., Duyndam, D., Kwa, V. I., Meijer, F. J., van Dijk, E. J., Kesselring, F. O., Hofmeijer, J., Vos, J. A., Schonewille, W. J., van Rooij, W. J., de Kort, P. L., Pleiter, C. C., Bakker, S. L., Bot, J., Visser, M. C., Velthuis, B. K., van der Schaaf, I. C., Dankbaar, J. W., Mali, W. P., van Seeters, T., Horsch, A. D., Niesten, J. M., Biessels, G. J., Kappelle, L. J., Luitse, M. J., and van der Graaf, Y.

Published
2016

25. Assessment of collateral status by dynamic ct angiography in acute mca stroke : Timing of acquisition and relationship with final infarct volume

Author

Van Den Wijngaard, I. R., Holswilder, G., Wermer, M. J H, Boiten, J., Algra, A., Dippel, D. W J, Dankbaar, J. W., Velthuis, B. K., Boers, A. M M, Majoie, C. B L M, Van Walderveen, M. A A, Van Den Wijngaard, I. R., Holswilder, G., Wermer, M. J H, Boiten, J., Algra, A., Dippel, D. W J, Dankbaar, J. W., Velthuis, B. K., Boers, A. M M, Majoie, C. B L M, and Van Walderveen, M. A A

Published
2016

26. Safety of intra-arterial treatment in acute ischaemic stroke patients on oral anticoagulants. A cohort study and systematic review

Author

Circulatory Health, JC onderzoeksprogramma Cardiovasculaire Epidemiologie, Brain, Cardiovasculaire Epi Team 6, Rozeman, A. D., Wermer, M. J H, Lycklama à Nijeholt, G. J., Dippel, D. W J, Schonewille, W. J., Boiten, J., Algra, A., Circulatory Health, JC onderzoeksprogramma Cardiovasculaire Epidemiologie, Brain, Cardiovasculaire Epi Team 6, Rozeman, A. D., Wermer, M. J H, Lycklama à Nijeholt, G. J., Dippel, D. W J, Schonewille, W. J., Boiten, J., and Algra, A.

Published
2016

27. Temporal profile of body temperature in acute ischemic stroke: Relation to infarct size and outcome

Author

Opleiding Neurologie, Brain, Arts-assistenten Radiologie, ZL Algemene Neurologie Medisch, Circulatory Health, ZL Cerebrovasculaire Ziekten Medisch, MS Radiologie, Cancer, Onderzoek Beeld, Cardiovasculaire Epi Team 7, JC onderzoeksprogramma Cardiovasculaire Epidemiologie, Geurts, Marjolein, Scheijmans, Féline E V, van Seeters, Tom, Biessels, Geert J., Kappelle, L. Jaap, Velthuis, Birgitta K., van der Worp, H. Bart, Majoie, C. B., Roos, Y. B., Duijm, L. E., Keizer, K., van der Lugt, A., Dippel, D. W., Greve, Droogh de, Bienfait, H. P., van Walderveen, M. A., Wermer, M. J., Lycklama à Nijeholt, G. J., Boiten, J., Duyndam, D., Kwa, V. I., Meijer, F. J., van Dijk, E. J., Kesselring, F. O., Hofmeijer, J., Vos, J. A., Schonewille, W. J., van Rooij, W. J., de Kort, P. L., Pleiter, C. C., Bakker, S. L., Bot, J., Visser, M. C., Velthuis, B. K., van der Schaaf, I. C., Dankbaar, J. W., Mali, W. P., van Seeters, T., Horsch, A. D., Niesten, J. M., Biessels, G. J., Kappelle, L. J., Luitse, M. J., van der Graaf, Y., Opleiding Neurologie, Brain, Arts-assistenten Radiologie, ZL Algemene Neurologie Medisch, Circulatory Health, ZL Cerebrovasculaire Ziekten Medisch, MS Radiologie, Cancer, Onderzoek Beeld, Cardiovasculaire Epi Team 7, JC onderzoeksprogramma Cardiovasculaire Epidemiologie, Geurts, Marjolein, Scheijmans, Féline E V, van Seeters, Tom, Biessels, Geert J., Kappelle, L. Jaap, Velthuis, Birgitta K., van der Worp, H. Bart, Majoie, C. B., Roos, Y. B., Duijm, L. E., Keizer, K., van der Lugt, A., Dippel, D. W., Greve, Droogh de, Bienfait, H. P., van Walderveen, M. A., Wermer, M. J., Lycklama à Nijeholt, G. J., Boiten, J., Duyndam, D., Kwa, V. I., Meijer, F. J., van Dijk, E. J., Kesselring, F. O., Hofmeijer, J., Vos, J. A., Schonewille, W. J., van Rooij, W. J., de Kort, P. L., Pleiter, C. C., Bakker, S. L., Bot, J., Visser, M. C., Velthuis, B. K., van der Schaaf, I. C., Dankbaar, J. W., Mali, W. P., van Seeters, T., Horsch, A. D., Niesten, J. M., Biessels, G. J., Kappelle, L. J., Luitse, M. J., and van der Graaf, Y.

Published
2016

28. Assessment of collateral status by dynamic ct angiography in acute mca stroke: Timing of acquisition and relationship with final infarct volume

Author

ZL Cerebrovasculaire Ziekten Medisch, Cardiovasculaire Epi Team 6, Circulatory Health, Brain, JC onderzoeksprogramma Cardiovasculaire Epidemiologie, MS Radiologie, Van Den Wijngaard, I. R., Holswilder, G., Wermer, M. J H, Boiten, J., Algra, A., Dippel, D. W J, Dankbaar, J. W., Velthuis, B. K., Boers, A. M M, Majoie, C. B L M, Van Walderveen, M. A A, ZL Cerebrovasculaire Ziekten Medisch, Cardiovasculaire Epi Team 6, Circulatory Health, Brain, JC onderzoeksprogramma Cardiovasculaire Epidemiologie, MS Radiologie, Van Den Wijngaard, I. R., Holswilder, G., Wermer, M. J H, Boiten, J., Algra, A., Dippel, D. W J, Dankbaar, J. W., Velthuis, B. K., Boers, A. M M, Majoie, C. B L M, and Van Walderveen, M. A A

Published
2016

29. Prediction of outcome in patients with suspected acute ischaemic stroke with CT perfusion and CT angiography: the Dutch acute stroke trial (DUST) study protocol

Author

Van Seeters, Tom, Biessels, Geert J., van der Schaaf, Irene C., Dankbaar, Jan W., Horsch, Alexander D., Luitse, Merel J.A., Niesten, Joris M., Mali, Willem P.T.M., Kappelle, L. J., van der Graaf, Yolanda, Velthuis, Birgitta K., Majoie, C. B., Roos, Y. B., Duijm, L. E., Keizer, K., van der Lugt, A., Dippel, D. W., Droogh-de Greeve, K. E., Bienfait, H. P., van Walderveen, M. A., Wermer, M. J., Lycklamaà Nijeholt, G. J., Boiten, J., Duyndam, D., Kwa, V. I., Meijer, F. J., van Dijk, E. J., Kesselring, F. O., Hofmeijer, J., Vos, J. A., Schonewille, W. J., van Rooij, W. J., de Kort, P. L., Pleiter, C. C., Bakker, S. L., Bot, J., Visser, M. C., ACS - Amsterdam Cardiovascular Sciences, ANS - Amsterdam Neuroscience, Radiology and Nuclear Medicine, Neurology, Public Health, Radiology and nuclear medicine, and Public and occupational health

Subjects
medicine.medical_specialty, Infarct, Clinical Neurology, Perfusion scanning, Ischaemia, Brain Ischemia, Cohort Studies, Study Protocol, Modified Rankin Scale, Predictive Value of Tests, medicine, Humans, Prospective Studies, Stage (cooking), Prospective cohort study, Stroke, Netherlands, Receiver operating characteristic, medicine.diagnostic_test, business.industry, General Medicine, Disorders of movement Donders Center for Medical Neuroscience [Radboudumc 3], medicine.disease, Cerebral Angiography, Perfusion, Treatment Outcome, CT angiography, Predictive value of tests, Angiography, CT perfusion, Neurology (clinical), Radiology, business, Prediction, Tomography, X-Ray Computed, Follow-Up Studies
Abstract

Contains fulltext : 136571.pdf (Publisher’s version ) (Open Access) BACKGROUND: Prediction of clinical outcome in the acute stage of ischaemic stroke can be difficult when based on patient characteristics, clinical findings and on non-contrast CT. CT perfusion and CT angiography may provide additional prognostic information and guide treatment in the early stage. We present the study protocol of the Dutch acute Stroke Trial (DUST). The DUST aims to assess the prognostic value of CT perfusion and CT angiography in predicting stroke outcome, in addition to patient characteristics and non-contrast CT. For this purpose, individualised prediction models for clinical outcome after stroke based on the best predictors from patient characteristics and CT imaging will be developed and validated. METHODS/DESIGN: The DUST is a prospective multi-centre cohort study in 1500 patients with suspected acute ischaemic stroke. All patients undergo non-contrast CT, CT perfusion and CT angiography within 9 hours after onset of the neurological deficits, and, if possible, follow-up imaging after 3 days. The primary outcome is a dichotomised score on the modified Rankin Scale, assessed at 90 days. A score of 0-2 represents good outcome, and a score of 3-6 represents poor outcome. Three logistic regression models will be developed, including patient characteristics and non-contrast CT (model A), with addition of CT angiography (model B), and CT perfusion parameters (model C). Model derivation will be performed in 60% of the study population, and model validation in the remaining 40% of the patients. Additional prognostic value of the models will be determined with the area under the curve (AUC) from the receiver operating characteristic (ROC) curve, calibration plots, assessment of goodness-of-fit, and likelihood ratio tests. DISCUSSION: This study will provide insight in the added prognostic value of CTP and CTA parameters in outcome prediction of acute stroke patients. The prediction models that will be developed in this study may help guide future treatment decisions in the acute stage of ischaemic stroke.

Published
2014

30. Assessment of Collateral Status by Dynamic CT Angiography in Acute MCA Stroke: Timing of Acquisition and Relationship with Final Infarct Volume

Author

van den Wijngaard, I. R., primary, Holswilder, G., additional, Wermer, M. J. H., additional, Boiten, J., additional, Algra, A., additional, Dippel, D. W. J., additional, Dankbaar, J. W., additional, Velthuis, B. K., additional, Boers, A. M. M., additional, Majoie, C. B. L. M., additional, and van Walderveen, M. A. A., additional

Published
2016
Full Text
View/download PDF

31. The ThRombolysis in UnconTrolled Hypertension (TRUTH) protocol : an observational study on treatment strategy of elevated blood pressure in stroke patients eligible for IVT

Author

Zonneveld, T P, Algra, A, Dippel, D W J, Kappelle, L J, van Oostenbrugge, R J, Roos, Y B W E M, Wermer, M J, van der Worp, H B, Nederkoorn, P J, Kruyt, N D, TRUTH investigators, Zonneveld, T P, Algra, A, Dippel, D W J, Kappelle, L J, van Oostenbrugge, R J, Roos, Y B W E M, Wermer, M J, van der Worp, H B, Nederkoorn, P J, Kruyt, N D, and TRUTH investigators

Published
2015

32. The value of CT angiography in patients with acute severe headache

Author

Alons, I. M E, van den Wijngaard, I. R., Verheul, R. J., Lycklama à Nijeholt, G., Wermer, M. J H, Algra, A., Jellema, K., Alons, I. M E, van den Wijngaard, I. R., Verheul, R. J., Lycklama à Nijeholt, G., Wermer, M. J H, Algra, A., and Jellema, K.

Published
2015

33. The ThRombolysis in UnconTrolled Hypertension (TRUTH) protocol: an observational study on treatment strategy of elevated blood pressure in stroke patients eligible for IVT

Author

ZL Cerebrovasculaire Ziekten Medisch, Circulatory Health, JC onderzoeksprogramma Cardiovasculaire Epidemiologie, Cardiovasculaire Epi Team 6, ZL Algemene Neurologie Medisch, Zonneveld, T P, Algra, A, Dippel, D W J, Kappelle, L J, van Oostenbrugge, R J, Roos, Y B W E M, Wermer, M J, van der Worp, H B, Nederkoorn, P J, Kruyt, N D, TRUTH investigators, ZL Cerebrovasculaire Ziekten Medisch, Circulatory Health, JC onderzoeksprogramma Cardiovasculaire Epidemiologie, Cardiovasculaire Epi Team 6, ZL Algemene Neurologie Medisch, Zonneveld, T P, Algra, A, Dippel, D W J, Kappelle, L J, van Oostenbrugge, R J, Roos, Y B W E M, Wermer, M J, van der Worp, H B, Nederkoorn, P J, Kruyt, N D, and TRUTH investigators

Published
2015

34. The value of CT angiography in patients with acute severe headache

Author

Circulatory Health, JC onderzoeksprogramma Cardiovasculaire Epidemiologie, Brain, Cardiovasculaire Epi Team 6, Alons, I. M E, van den Wijngaard, I. R., Verheul, R. J., Lycklama à Nijeholt, G., Wermer, M. J H, Algra, A., Jellema, K., Circulatory Health, JC onderzoeksprogramma Cardiovasculaire Epidemiologie, Brain, Cardiovasculaire Epi Team 6, Alons, I. M E, van den Wijngaard, I. R., Verheul, R. J., Lycklama à Nijeholt, G., Wermer, M. J H, Algra, A., and Jellema, K.

Published
2015

35. [Ischemic stroke in young women]

Author

Ekker, M. S., Wermer, M. J. H., Riksen, N. P., C.J.M. Klijn, and Leeuw, F. E.

Subjects
Vascular damage Radboud Institute for Molecular Life Sciences [Radboudumc 16], cardiovascular diseases, Disorders of movement Donders Center for Medical Neuroscience [Radboudumc 3]
Abstract

Item does not contain fulltext - In virtually all age groups, the incidence of ischemic stroke is higher in men. However, in women aged between 25-49 years the prevalence is higher than in men. Female-specific risk factors and disorders may explain this peak.- Pregnancy and the post-partum period are associated with physiological changes which can increase blood coagulation. Complications during pregnancy may also increase the risk of ischaemic stroke.- Migraine with aura and antiphospholipid syndrome are disorders which are also associated with an increased risk of ischaemic stroke. These disorders are more common in women compared to men. Furthermore, hormonal contraceptives containing oestrogen are also identified to increase the incidence of ischaemic stroke.- The acute treatment and secondary prevention of ischaemic stroke in young women is identical to that in elderly stroke patients, be it men or women, although thrombolysis and platelet aggregation inhibition in pregnant women should be approached with care.- Clinical outcomes after stroke for women under the age of 50 are worse compared to age-matched men.

Published
2016

39. The ThRombolysis in UnconTrolled Hypertension (TRUTH) protocol: an observational study on treatment strategy of elevated blood pressure in stroke patients eligible for IVT.

Author

Zonneveld, T. P., Algra, A., Dippel, D. W. J., Kappelle, L. J., van Oostenbrugge, R. J., Roos, Y. B. W. E. M., Wermer, M. J., van der Worp, H. B., Nederkoorn, P. J., Kruyt, N. D., and TRUTH investigators

Subjects
HYPERTENSION, THROMBOLYTIC therapy, BLOOD pressure, HEMORRHAGE, STROKE, ANTIHYPERTENSIVE agents, FIBRINOLYTIC agents, CEREBRAL hemorrhage, CEREBRAL ischemia, INTRAVENOUS therapy, LONGITUDINAL method, DISEASE complications, TISSUE plasminogen activator, THERAPEUTICS
Abstract

Background: Intravenous thrombolysis (IVT) with (recombinant) tissue plasminogen activator is an effective treatment in acute ischemic stroke. However, IVT is contraindicated when blood pressure is above 185/110 mmHg, because of an increased risk on symptomatic intracranial hemorrhage. In current Dutch clinical practice, two distinct strategies are used in this situation. The active strategy comprises lowering blood pressure with antihypertensive agents below these thresholds to allow start of IVT. In the conservative strategy, IVT is administered only when blood pressure drops spontaneously below protocolled thresholds. A retrospective analysis in two recent stroke trials showed a non-significant signal towards better functional outcome in the active group; robust evidence for either strategy, however, is lacking. We hypothesize that (I) the active strategy leads to a better functional outcome three months after acute ischemic stroke. Secondary hypotheses are that this effect occurs despite (II) increasing the number of symptomatic intracranial hemorrhages, and could be attributable to (III) a higher rate of IVT treatments and (IV) a shorter door-to-needle time.Methods and Design: The TRUTH is a prospective, observational, cluster-based, parallel group follow-up study; in which participating centers continue their current local treatment guidelines. Outcomes of patients admitted to centers with an active will be compared to those admitted to centers with a conservative strategy. The primary outcome is functional outcome on the modified Rankin Scale at three months. Secondary outcomes are symptomatic intracranial hemorrhage, IVT treatment and door-to-needle time. We based our sample size estimate on an ordinal analysis of the mRS with the "proportional odds" model. With the aforementioned signal observed in a recent retrospective study in these patients as an estimate of the effect size and with alpha 0 · 05, this analysis would have an 80 % power with a total number of 600 patients. Corrections for expected imbalance in group size and clustering effects resulted in a sample size of 1235 patients.Discussion: The TRUTH is the first large prospective study specifically studying IVT-candidates with elevated blood pressure, and has the potential to change clinical practice and optimize acute stroke care in these patients. [ABSTRACT FROM AUTHOR]

Published
2015
Full Text
View/download PDF

40. The value of CT angiography in patients with acute severe headache.

Author

Alons, I. M. E., Wijngaard, I. R., Verheul, R. J., Lycklama à Nijeholt, G., Wermer, M. J. H., Algra, A., and Jellema, K.

Abstract

Patients with acute severe headache may have a secondary form of headache. Standard head computer tomography (CT) and cerebrospinal fluid (CSF) examination are often performed in the absence of neurological deficits to exclude subarachnoid hemorrhage (SAH). Increasingly, patients undergo subsequent CT angiography (CTA) to exclude cerebral venous thrombosis (CVT), dissection or reversible cerebral vasoconstriction syndrome (RCVS). It is unknown whether this additional imaging increases diagnostic yield. We aimed to evaluate the yield of CTA in patients with acute severe headache with normal neurological examination and no abnormalities at standard CT and CSF analysis. We included consecutive patients presenting to the emergency room between January 2008 and May 2011 with acute severe headache and without abnormalities at neurological examination, CT and CSF research, who received a CTA in the diagnostic process in our teaching hospital. All scans were rereviewed by an experienced neuroradiologist. We included 70 patients, 71% were women and average age was 45 years. We found a vascular abnormality in 13 (19%) of our patients. Four had either a prior aneurysm or CVT. Eight patients had an unruptured intracranial aneurysm (UIA) on CTA (11%), two had CVT (3%), two had RCVS (3%) and one had cerebral ischemia (1%). We found a high percentage of vascular abnormalities. A third of these patients had a prior episode of either an aneurysm or CVT. In patients with a history of UIA or CVT performing CTA despite normal CT and LP therefore seems warranted. A prospective study to delineate indications for CTA is needed. [ABSTRACT FROM AUTHOR]

Published
2015
Full Text
View/download PDF

41. CT after subarachnoid hemorrhage

Author

van der Schaaf, I., primary, Wermer, M. J., additional, van der Graaf, Y., additional, Hoff, R. G., additional, Rinkel, G.J.E., additional, and Velthuis, B. K., additional

Published
2006
Full Text
View/download PDF

46. A Randomized Trial of Intraarterial Treatment for Acute Ischemic Stroke.

Author

Berkhemer, O. A., Fransen, P. S. S., Beumer, D., van den Berg, L. A., Lingsma, H. F., Yoo, A. J., Schonewille, W. J., Vos, J. A., Nederkoorn, P. J., Wermer, M. J. H., van Walderveen, M. A. A., Staals, J., Hofmeijer, J., van Oostayen, J. A., Lycklama à Nijeholt, G. J., Boiten, J., Brouwer, P. A., Emmer, B. J., de Bruijn, S. F., and van Dijk, L. C.

Subjects
*STROKE treatment, *ARTERIAL occlusions, *ARTERIAL diseases, *CEREBRAL hemorrhage, *TREATMENT effectiveness
Abstract

The article presents a study on the intraarterial treatment for acute ischemic stroke caused by a proximal intracranial occlusion of the anterior circulation in the Netherlands. A randomized trial was conducted for 500 patients at 16 medical centers who were treated with intravenous alteplase before randomization. The study found no difference in mortality or the occurrence of symptomatic intracerebral haemorrhage, and the treatment was effective if given within six hours after stroke.

Published
2015
Full Text
View/download PDF

47. Quantitative electroencephalography in cerebral amyloid angiopathy.

Author

van der Plas MC, Rasing I, Geraedts VJ, Tromp SC, Terwindt GM, van Dort R, Kaushik K, van Zwet EW, Tannemaat MR, and Wermer MJH

Subjects
Humans, Male, Female, Aged, Middle Aged, Magnetic Resonance Imaging, Cognition physiology, Siderosis physiopathology, Siderosis diagnosis, Aged, 80 and over, Electroencephalography methods, Cerebral Amyloid Angiopathy physiopathology, Cerebral Amyloid Angiopathy diagnostic imaging
Abstract

Objective: We investigated whether quantitative electroencephalography (qEEG) correlates with cognition and cortical superficial siderosis (cSS) in cerebral amyloid angiopathy., Methods: We included patients with sporadic (sCAA) and hereditary Dutch-type CAA (D-CAA). Spectral measures and the phase lag index (PLI) were analyzed on qEEG. Cognition was assessed with the MoCA and cSS presence was scored on 3T-MRI. Linear regression analyses were performed to investigate these qEEG measures and cognition. Independent samples T-tests were used to analyze the qEEG measure differences between participants with and without cSS., Results: We included 92 participants (44 D-CAA; 48 sCAA). A lower average peak frequency (β[95 %CI] = 0.986[0.252-1.721]; P = 0.009) and a higher spectral ratio (β[95 %CI] = -0.918[-1.761--0.075]; P = 0.033) on qEEG correlated with a lower MoCA score, irrespective of a history of symptomatic intracerebral hemorrhage (sICH). The PLI showed no correlation to the MoCA. qEEG slowing was not different in those with or without cSS., Conclusions: Spectral qEEG (but not PLI) reflects cognitive performance in patients with CAA with and without a history of sICH. We found no association between qEEG slowing and cSS., Significance: qEEG could be a valuable biomarker, especially in challenging cognitive testing situations in CAA, and a potential predictive tool in future studies., (Copyright © 2024 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.)

Published
2024
Full Text
View/download PDF

48. Quantitative measurement of cortical superficial siderosis in cerebral amyloid angiopathy.

Author

van Harten TW, Koemans EA, Voigt S, Rasing I, van Osch MJP, van Walderveen MAA, and Wermer MJH

Subjects
Humans, Reproducibility of Results, Brain, Cerebral Hemorrhage diagnostic imaging, Cerebral Hemorrhage etiology, Magnetic Resonance Imaging, Siderosis complications, Siderosis diagnostic imaging, Cerebral Amyloid Angiopathy complications, Cerebral Amyloid Angiopathy diagnostic imaging
Abstract

Cerebral amyloid angiopathy (CAA) is a cerebrovascular disease affecting the small arteries in the brain with hallmark depositions of amyloid-β in the vessel wall, leading to cognitive decline and intracerebral hemorrhage (ICH). An emerging MRI marker for CAA is cortical superficial siderosis (cSS) as it is strongly related to the risk of (recurrent) ICH. Current assessment of cSS is mainly done on T2*- weighted MRI using a qualitative score consisting of 5 categories of severity which is hampered by ceiling effects. Therefore, the need for a more quantitative measurement is warranted to better map disease progression for prognosis and future therapeutic trials. We propose a semi-automated method to quantify cSS burden on MRI and investigated it in 20 patients with CAA and cSS. The method showed excellent inter-observer (Pearson's 0.991, P < 0.001) and intra-observer reproducibility (ICC 0.995, P < 0.001). Furthermore, in the highest category of the multifocality scale a large spread in the quantitative score is observed, demonstrating the ceiling effect in the traditional score. We observed a quantitative increase in cSS volume in two of the 5 patients who had a 1 year follow up, while the traditional qualitative method failed to identify an increase because these patients were already in the highest category. The proposed method could therefore potentially be a better way of tracking progression. In conclusion, semi-automated segmenting and quantifying cSS is feasible and repeatable and may be used for further studies in CAA cohorts., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Published
2023
Full Text
View/download PDF

49. Evolutionary algorithms and decision trees for predicting poor outcome after endovascular treatment for acute ischemic stroke.

Author

Kappelhof N, Ramos LA, Kappelhof M, van Os HJA, Chalos V, van Kranendonk KR, Kruyt ND, Roos YBWEM, van Zwam WH, van der Schaaf IC, van Walderveen MAA, Wermer MJH, van Oostenbrugge RJ, Lingsma H, Dippel D, Majoie CBLM, and Marquering HA

Subjects
Algorithms, Decision Trees, Humans, Brain Ischemia therapy, Ischemic Stroke, Stroke therapy
Abstract

Despite the large overall beneficial effects of endovascular treatment in patients with acute ischemic stroke, severe disability or death still occurs in almost one-third of patients. These patients, who might not benefit from treatment, have been previously identified with traditional logistic regression models, which may oversimplify relations between characteristics and outcome, or machine learning techniques, which may be difficult to interpret. We developed and evaluated a novel evolutionary algorithm for fuzzy decision trees to accurately identify patients with poor outcome after endovascular treatment, which was defined as having a modified Rankin Scale score (mRS) higher or equal to 5. The created decision trees have the benefit of being comprehensible, easily interpretable models, making its predictions easy to explain to patients and practitioners. Insights in the reason for the predicted outcome can encourage acceptance and adaptation in practice and help manage expectations after treatment. We compared our proposed method to CART, the benchmark decision tree algorithm, on classification accuracy and interpretability. The fuzzy decision tree significantly outperformed CART: using 5-fold cross-validation with on average 1090 patients in the training set and 273 patients in the test set, the fuzzy decision tree misclassified on average 77 (standard deviation of 7) patients compared to 83 (±7) using CART. The mean number of nodes (decision and leaf nodes) in the fuzzy decision tree was 11 (±2) compared to 26 (±1) for CART decision trees. With an average accuracy of 72% and much fewer nodes than CART, the developed evolutionary algorithm for fuzzy decision trees might be used to gain insights into the predictive value of patient characteristics and can contribute to the development of more accurate medical outcome prediction methods with improved clarity for practitioners and patients., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Published
2021
Full Text
View/download PDF

50. On the ability to exploit signal fluctuations in pseudocontinuous arterial spin labeling for inferring the major flow territories from a traditional perfusion scan.

Author

van Harten TW, Dzyubachyk O, Bokkers RPH, Wermer MJH, and van Osch MJP

Subjects
Adult, Aged, Aged, 80 and over, Blood Flow Velocity physiology, Brain diagnostic imaging, Carotid Artery, Internal diagnostic imaging, Female, Humans, Magnetic Resonance Imaging methods, Male, Middle Aged, Brain blood supply, Brain physiology, Carotid Artery, Internal physiology, Cerebrovascular Circulation physiology, Perfusion Imaging methods, Spin Labels
Abstract

In arterial spin labeling (ASL) a magnetic label is applied to the flowing blood in feeding arteries allowing depiction of cerebral perfusion maps. The labeling efficiency depends, however, on blood velocity and local field inhomogeneities and is, therefore, not constant over time. In this work, we investigate the ability of statistical methods used in functional connectivity research to infer flow territory information from traditional pseudo-continuous ASL (pCASL) scans by exploiting artery-specific signal fluctuations. By applying an additional gradient during labeling the minimum amount of signal fluctuation that allows discrimination of the main flow territories is determined. The following three approaches were tested for their performance on inferring the large vessel flow territories of the brain: a general linear model (GLM), an independent component analysis (ICA) and t-stochastic neighbor embedding. Furthermore, to investigate the effect of large vessel pathology, standard ASL scans of three patients with a unilateral stenosis (>70%) of one of the internal carotid arteries were retrospectively analyzed using ICA and t-SNE. Our results suggest that the amount of natural-occurring variation in labeling efficiency is insufficient to determine large vessel flow territories. When applying additional vessel-encoded gradients these methods are able to distinguish flow territories from one another, but this would result in approximately 8.5% lower perfusion signal and thus also a reduction in SNR of the same magnitude., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Published
2021
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results