13,731 results match your criteria American Journal Of Neuroradiology[Journal]


MTT Heterogeneity in Perfusion CT Imaging as a Predictor of Outcome after Aneurysmal SAH.

AJNR Am J Neuroradiol 2021 Jun 3. Epub 2021 Jun 3.

Diagnostic and Interventional Radiology (K.J., B.T., C.R.), Medical Faculty, University Düsseldorf, Düsseldorf, Germany.

Background And Purpose: Impairment of tissue oxygenation caused by inhomogeneous microscopic blood flow distribution, the so-called capillary transit time heterogeneity, is thought to contribute to delayed cerebral ischemia after aneurysmal SAH but has so far not been systematically evaluated in patients. We hypothesized that heterogeneity of the MTT, derived from CTP parameters, would give insight into the clinical course of patients with aneurysmal SAH and may identify patients at risk of poor outcome.

Materials And Methods: We retrospectively analyzed the heterogeneity of the MTT using the coefficient of variation in CTP scans from 132 patients. Read More

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MTT and Blood-Brain Barrier Disruption within Asymptomatic Vascular WM Lesions.

AJNR Am J Neuroradiol 2021 Jun 3. Epub 2021 Jun 3.

Department of Neurology (R.L., P.N.), Johns Hopkins University, Baltimore, Maryland

Background And Purpose: White matter lesions of presumed ischemic origin are associated with progressive cognitive impairment and impaired BBB function. Studying the longitudinal effects of white matter lesion biomarkers that measure changes in perfusion and BBB patency within white matter lesions is required for long-term studies of lesion progression. We studied perfusion and BBB disruption within white matter lesions in asymptomatic subjects. Read More

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CT-Guided Caudal Epidural Infiltrations: A Technical Note.

Authors:
J Gossner

AJNR Am J Neuroradiol 2021 Jun 3. Epub 2021 Jun 3.

Department of Diagnostic and Interventional RadiologyEvangelisches Krankenhaus Göttingen-WeendeGöttingen, Germany.

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Infarct Growth despite Successful Endovascular Reperfusion in Acute Ischemic Stroke: A Meta-analysis.

AJNR Am J Neuroradiol 2021 Jun 3. Epub 2021 Jun 3.

From the Calgary Stroke Program (F.B., J.O., B.K.M., M.G., M.A.A.)

Background: Infarct volume inversely correlates with good recovery in stroke. The magnitude and predictors of infarct growth despite successful reperfusion via endovascular treatment are not known.

Purpose: We aimed to summarize the extent of infarct growth in patients with acute stroke who achieved successful reperfusion (TICI 2b-3) after endovascular treatment. Read More

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Linking Stage-Specific Plasma Biomarkers to Gray Matter Atrophy in Parkinson Disease.

AJNR Am J Neuroradiol 2021 May 27. Epub 2021 May 27.

Institute of Neuroscience (P.-L.L., C.-P.L., K.-H.C.)

Background And Purpose: The shortcomings of synucleinopathy-based Parkinson disease staging highlight the need for systematic clinicopathologic elucidation and biomarkers. In this study, we investigated associations of proteinopathy and inflammation markers with changes in gray matter volume that accompany Parkinson disease progression.

Materials And Methods: We prospectively enrolled 42 patients with idiopathic Parkinson disease, subdivided into early-/late-stage groups and 27 healthy controls. Read More

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Prognostic Utility of Disproportionately Enlarged Subarachnoid Space Hydrocephalus in Idiopathic Normal Pressure Hydrocephalus Treated with Ventriculoperitoneal Shunt Surgery: A Systematic Review and Meta-analysis.

AJNR Am J Neuroradiol 2021 May 27. Epub 2021 May 27.

From the Departments of Radiology and Research Institute of Radiology (H.Y.P., C.H.S., M.J.K., W.H.S., S.J.K.), Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.

Background: Disproportionately enlarged subarachnoid space hydrocephalus is a specific radiologic marker for idiopathic normal pressure hydrocephalus. However, controversy exists regarding the prognostic utility of disproportionately enlarged subarachnoid space hydrocephalus.

Purpose: Our aim was to evaluate the prevalence of disproportionately enlarged subarachnoid space hydrocephalus in idiopathic normal pressure hydrocephalus and its predictive utility regarding prognosis in patients treated with ventriculoperitoneal shunt surgery. Read More

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Clinical and Procedural Outcomes with or without Balloon Guide Catheters during Endovascular Thrombectomy in Acute Ischemic Stroke: A Systematic Review and Meta-analysis with First-line Technique Subgroup Analysis.

AJNR Am J Neuroradiol 2021 May 27. Epub 2021 May 27.

Department of Clinical Neurosciences (G.J., A.S., M.G., M.A.), University of Calgary, Calgary, Alberta, Canada.

Background: Balloon guide catheters are increasingly used to improve clot retrieval by temporarily stopping proximal blood flow during endovascular thrombectomy.

Purpose: Our aim was to provide a summary of the literature comparing the procedural and clinical outcomes of endovascular thrombectomy with or without balloon guide catheters, depending on the first-line technique used.

Data Sources: We used PubMed/MEDLINE, EMBASE, and the Cochrane Database of Systematic Reviews. Read More

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Robert A. Zimmerman, MD.

AJNR Am J Neuroradiol 2021 May 20. Epub 2021 May 20.

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Diagnostic Accuracy of Screening Arterial Spin-Labeling MRI Using Hadamard Encoding for the Detection of Reduced CBF in Adult Patients with Ischemic Moyamoya Disease.

AJNR Am J Neuroradiol 2021 May 20. Epub 2021 May 20.

From the Department of Neurosurgery (K.S., T.C., S.F., M.K., K. Yoshida, Y. Kubo, K.O.), Institute for Biomedical Sciences, Iwate Medical University School of Medicine, Yahaba-cho, Japan

Background And Purpose: Adult patients with ischemic Moyamoya disease are advised to undergo selective revascularization surgery based on cerebral hemodynamics. The purpose of this study was to determine the diagnostic accuracy of arterial spin-labeling MR imaging using Hadamard-encoded multiple postlabeling delays for the detection of reduced CBF in such patients.

Materials And Methods: Thirty-seven patients underwent brain perfusion SPECT and pseudocontinuous arterial spin-labeling MR imaging using standard postlabeling delay (1525 ms) and Hadamard-encoded multiple postlabeling delays. Read More

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Reply.

AJNR Am J Neuroradiol 2021 May 20. Epub 2021 May 20.

Department of NeuroradiologyKing's College Hospital, National Health Service Foundation TrustLondon, United KingdomSchool of Biomedical Engineering and Imaging SciencesKing's College LondonLondon, United Kingdom.

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COVID-19 Stroke Apical Lung Exam Study: Is it Really an Accurate Diagnostic Method?

AJNR Am J Neuroradiol 2021 May 20. Epub 2021 May 20.

Diagnostic Imaging DepartmentFundacion Santa Fe De Bogota University HospitalBogotá, Colombia.

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Collicular Hyperactivation in Patients with COVID-19: A New Finding on Brain MRI and PET/CT.

AJNR Am J Neuroradiol 2021 May 20. Epub 2021 May 20.

Service de Médecine Nucléaire (C.B., I.J.N.), Institut de Cancérologie Strasbourg Europe, Strasbourg, France.

Hyperactivation of the colliculi has been observed in some patients with coronavirus disease 2019. Read More

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AJNR Am J Neuroradiol 2021 May 20. Epub 2021 May 20.

Neuroendovascular Service, Marcus Stroke & Neuroscience CenterGrady Memorial HospitalAtlanta, GeorgiaNeurology, Neurosurgery, and RadiologyEmory University School of MedicineAtlanta, Georgia.

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The True Potential of Artificial Intelligence for Detection of Large-Vessel Occlusion: The Role of M2 Occlusions.

AJNR Am J Neuroradiol 2021 May 20. Epub 2021 May 20.

Department of Radiology and Nuclear MedicineErasmus MC University Medical CenterRotterdam, The Netherlands.

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Reply.

AJNR Am J Neuroradiol 2021 May 13. Epub 2021 May 13.

NeurosurgeryUniversity of California, San FranciscoSan Francisco, California.

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Assessment of MR Imaging and CT in Differentiating Hereditary and Nonhereditary Paragangliomas.

AJNR Am J Neuroradiol 2021 May 13. Epub 2021 May 13.

From the Division of Neuroradiology (Y.O., S.N., J.R.B., A.C., J.K., T.M., A.S.), Department of Radiology, University of Michigan, Ann Arbor, Michigan.

Background And Purpose: Head and neck paragangliomas have been reported to be associated with mutations of the succinate dehydrogenase enzyme family. The aim of this study was to assess whether radiologic features could differentiate between paragangliomas in the head and neck positive and negative for the succinate dehydrogenase mutation.

Materials And Methods: This single-center retrospective review from January 2015 to January 2020 included 40 patients with 48 paragangliomas (30 tumors positive for succinate dehydrogenase mutation in 23 patients and 18 tumors negative for the succinate dehydrogenase mutation in 17 patients). Read More

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AJNR Am J Neuroradiol 2021 May 13. Epub 2021 May 13.

Department of Radiology, Division of Cardiothoracic ImagingWestchester Medical CenterValhalla, New York.

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T1 Mapping for Microstructural Assessment of the Cervical Spinal Cord in the Evaluation of Patients with Degenerative Cervical Myelopathy.

AJNR Am J Neuroradiol 2021 May 13. Epub 2021 May 13.

Center for Magnetic Resonance in Biology and Medicine (G.B., H.R., L.P., S.L., V.C.), Assistance Publique-Hôpitaux de Marseille, Hôpital Universitaire Timone, Marseille, France

Background And Purpose: Although current radiologic evaluation of degenerative cervical myelopathy by conventional MR imaging accurately demonstrates spondylosis or degenerative disc disease causing spinal cord dysfunction, conventional MR imaging still fails to provide satisfactory anatomic and clinical correlations. In this context, we assessed the potential value of quantitative cervical spinal cord T1 mapping regarding the evaluation of patients with degenerative cervical myelopathy.

Materials And Methods: Twenty patients diagnosed with mild and moderate-to-severe degenerative cervical myelopathy and 10 healthy subjects were enrolled in a multiparametric MR imaging protocol. Read More

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Leptomeningeal Enhancement Due to COVID-19 on 3D-FLAIR and T1 Black-Blood MR Imaging Sequences.

AJNR Am J Neuroradiol 2021 May 13. Epub 2021 May 13.

Department of Clinical TherapeuticsMedical School, National and Kapodistrian University of AthensAthens, Greece.

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MRI-Visible Perivascular Spaces in the Centrum Semiovale Are Associated with Brain Amyloid Deposition in Patients with Alzheimer Disease-Related Cognitive Impairment.

AJNR Am J Neuroradiol 2021 May 13. Epub 2021 May 13.

From the Department of Nuclear Medicine (H.J.K., Y.H.R.), Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, South Korea.

Background And Purpose: The association of perivascular spaces in the centrum semiovale with amyloid accumulation among patients with Alzheimer disease-related cognitive impairment is unknown. We evaluated this association in patients with Alzheimer disease-related cognitive impairment and β-amyloid deposition, assessed with [F] florbetaben PET/CT.

Materials And Methods: MR imaging and [F] florbetaben PET/CT images of 144 patients with Alzheimer disease-related cognitive impairment were retrospectively evaluated. Read More

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Prevalence of Cervical Artery Abnormalities on CTA in Patients with Spontaneous Coronary Artery Dissection: Fibromuscular Dysplasia, Dissection, Aneurysm, and Tortuosity.

AJNR Am J Neuroradiol 2021 May 13. Epub 2021 May 13.

Department of Cardiovascular Medicine (S.N.H., M.S.T.), Mayo Clinic, Rochester, Minnesota.

Background And Purpose: Little is known about associations between spontaneous coronary artery dissection and cervical artery abnormalities. This study sought to assess the prevalence of cervical artery abnormalities among patients with spontaneous coronary artery dissection.

Materials And Methods: A retrospective analysis was completed of patients who underwent CTA neck imaging as part of arterial assessment following the diagnosis of spontaneous coronary artery dissection. Read More

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Asynchrony in Peritumoral Resting-State Blood Oxygen Level-Dependent fMRI Predicts Meningioma Grade and Invasion.

AJNR Am J Neuroradiol 2021 May 13. Epub 2021 May 13.

Department of Radiology (J.G.), Columbia University, New York, New York

Background And Purpose: Meningioma grade is determined by histologic analysis, with detectable brain invasion resulting in a diagnosis of grade II or III tumor. However, tissue undersampling is a common problem, and invasive parts of the tumor can be missed, resulting in the incorrect assignment of a lower grade. Radiographic biomarkers may be able to improve the diagnosis of grade and identify targets for biopsy. Read More

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MRI Shrimp Sign in Cerebellar Progressive Multifocal Leukoencephalopathy: Description and Validation of a Novel Observation.

AJNR Am J Neuroradiol 2021 May 13. Epub 2021 May 13.

From the Department of Neurology (N.A., A.E.G., S.S.M., N.V., J.D.S.), Ataxia Center, Cognitive Behavioral Neurology Unit, Laboratory for Neuroanatomy and Cerebellar Neurobiology, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts

Background And Purpose: There are no validated imaging criteria for the diagnosis of progressive multifocal leukoencephalopathy in the cerebellum. Here we introduce the MR imaging shrimp sign, a cerebellar white matter lesion identifiable in patients with cerebellar progressive multifocal leukoencephalopathy, and we evaluate its sensitivity and specificity.

Materials And Methods: We first identified patients with progressive multifocal leukoencephalopathy seen at Massachusetts General Hospital between 1998 and 2019 whose radiology reports included the term "cerebellum. Read More

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Convolutional Neural Network to Stratify the Malignancy Risk of Thyroid Nodules: Diagnostic Performance Compared with the American College of Radiology Thyroid Imaging Reporting and Data System Implemented by Experienced Radiologists.

AJNR Am J Neuroradiol 2021 May 13. Epub 2021 May 13.

From the Department of Radiology (G.R.K., J.H.Y., V.Y.P., J.Y.K.), Severance Hospital, Research Institute of Radiological Science, Center for Clinical Imaging Data Science, Yonsei University College of Medicine, Seoul, Korea

Background And Purpose: Comparison of the diagnostic performance for thyroid cancer on ultrasound between a convolutional neural network and visual assessment by radiologists has been inconsistent. Thus, we aimed to evaluate the diagnostic performance of the convolutional neural network compared with the American College of Radiology Thyroid Imaging Reporting and Data System (TI-RADS) for the diagnosis of thyroid cancer using ultrasound images.

Materials And Methods: From March 2019 to September 2019, seven hundred sixty thyroid nodules (≥10 mm) in 757 patients were diagnosed as benign or malignant through fine-needle aspiration, core needle biopsy, or an operation. Read More

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Simultaneous Multislice for Accelerating Diffusion MRI in Clinical Neuroradiology Protocols.

AJNR Am J Neuroradiol 2021 May 13. Epub 2021 May 13.

Department of Radiology (M.B., Y.W.L., E.F., T.M.S.), New York University Langone School of Medicine, New York, New York

Background And Purpose: Diffusion MR imaging sequences essential for clinical neuroradiology imaging protocols may be accelerated with simultaneous multislice acquisitions. We tested whether simultaneous multislice-accelerated diffusion data were clinically equivalent to standard acquisitions.

Materials And Methods: In this retrospective study, clinical diffusion sequences obtained before and after implementation of 2-slice simultaneous multislice acceleration and an altered diffusion gradient sampling scheme using the same 3T MRI scanner and 20-channel coil ( = 25 per group) were independently and blindly evaluated by 2 neuroradiologists for perceived quality, artifacts, and overall diagnostic utility. Read More

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Functional MRI Shows Altered Deactivation and a Corresponding Decrease in Functional Connectivity of the Default Mode Network in Patients with Gliomas.

AJNR Am J Neuroradiol 2021 May 13. Epub 2021 May 13.

From the Department of Radiology (Y.M.M., K.K.P., M.J., M.G., A.I.H.), Memorial Sloan Kettering Cancer Center, New York, New York.

Background And Purpose: The default mode network normally decreases in activity during externally directed tasks. Although default mode network connectivity is disrupted in numerous brain pathologies, default mode network deactivation has not been studied in patients with brain tumors. We investigated default mode network deactivation with language task-based fMRI by measuring the anticorrelation of a critical default mode network node, the posterior cingulate cortex, in patients with gliomas and controls; furthermore, we examined default mode network functional connectivity in these patients with task-based and resting-state fMRI. Read More

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Relationship between Shear Stiffness Measured by MR Elastography and Perfusion Metrics Measured by Perfusion CT of Meningiomas.

AJNR Am J Neuroradiol 2021 May 13. Epub 2021 May 13.

Department of Radiology (Y.S., H.O.), University of Yamanashi, Yamanashi, Japan.

Background And Purpose: When managing meningiomas, intraoperative tumor consistency and histologic subtype are indispensable factors influencing operative strategy. The purposes of this study were the following: 1) to investigate the correlation between stiffness assessed with MR elastography and perfusion metrics from perfusion CT, 2) to evaluate whether MR elastography and perfusion CT could predict intraoperative tumor consistency, and 3) to explore the predictive value of stiffness and perfusion metrics in distinguishing among histologic subtypes of meningioma.

Materials And Methods: Mean tumor stiffness and relative perfusion metrics (blood flow, blood volume, and MTT) were calculated (relative to normal brain tissue) for 14 patients with meningiomas who underwent MR elastography and perfusion CT before surgery (cohort 1). Read More

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