Anatomic imaging study of luminal diameter of the circle of Willis in patients with ischemic stroke

Objectives: Stroke or cerebrovascular accident is associated with defects in the circle of Willis; the vascular network that supplies the brain. There is currently lack of literature on the involvement of the circle of Willis in patients with stroke or its association with impending stroke. The objective of the study was to evaluate luminal diameter of arteries that constitute the circle of Willis in patients with stroke using computed tomography angiography (CTA) and magnetic resonance imaging (MRI) scans. Material and Methods: Angiograms of 340 male and female patients aged 15–>75 (40.18 ± 1.1 and 43.68 ± 1.18) years with suspected stroke, referred for either brain CTA or MRI in selected hospitals/diagnostic centers in Nigeria were evaluated using RadiAnt and the MicroDicom viewer software applications. A retrospective descriptive research design was adopted with approval from the federal health research ethics committee. Direct measurement of luminal diameter of major arteries of the circle of Willis was done using SPSS version 25 at P < 0.05. Results: From the 340 images assessed, 256 (75.29%) patients had ischemic stroke with luminal diameter of arteries of the circle of Willis ranged from 1 mm to >3 mm while 84 (24.71%) patients were without stroke with luminal diameter ranged from 1 mm to 2.11 mm (P < 0.05). Conclusion: Patients with stroke have larger luminal diameter of arteries that form the circle of Willis when compared to patients without stroke. The study has established for the 1st time, luminal diameter of circle of Willis that may be an index in the sampled Nigerian population.

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Thalamic Stroke: Precursors and Outcomes for Ten Patients

Brain Impairment ◽

10.1017/brimp.2014.4 ◽

2014 ◽

Vol 15 (1) ◽

pp. 51-57 ◽

Cited By ~ 1

Author(s):

Johanna Freeland ◽

Christopher Levi ◽

Mick Hunter

Keyword(s):

Risk Factors ◽

Basilar Artery ◽

Circle Of Willis ◽

Mood Changes ◽

Thalamic Stroke ◽

Susceptibility Factors ◽

Mri Scans ◽

Magnetic Resonance Imaging Mri ◽

Cognitive Screen ◽

Rehabilitation Needs

Objective: The purpose of this study was to examine susceptibility factors in thalamic stroke, as well as outcomes in order to identify rehabilitation needs.Methods: Ten patients with thalamic stroke were interviewed and administered the Audio Recorded Cognitive Screen. Magnetic resonance imaging (MRI) scans were examined to determine location and size of the lesion, as well as basilar artery size and anatomical variances in the circle of Willis.Results: Risk factors such as high cholesterol, high blood pressure and pre-existing heart conditions were identified. Circle of Willis variations were found in 6 of the 10 participants, with MR angiography indicating that the posterior communication artery was absent or failed to join the posterior cerebral artery. Basilar artery diameter measurements were no larger than normal. All participants reported post-stroke changes, including decreased coordination and mobility, poor balance, reduced energy, memory deficits and mood changes. Participants’ overall scores on cognitive tests were significantly lower than age-matched norms. Performance on the test domains of memory, fluency, language and attention were all significantly below age norms.Conclusions: The variability of outcome measures demonstrates the difficulty of defining patterns of relationship between risk factors and severity of functional sequelae in thalamic stroke.

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MRI versus CT for Detecting Acute Intracerebral Hemorrhage in Stroke Patients

10.1093/med/9780190223700.003.0004 ◽

2016 ◽

Author(s):

Christoph I. Lee

Keyword(s):

Intracerebral Hemorrhage ◽

Resonance Imaging ◽

Stroke Patients ◽

Acute Hemorrhage ◽

Additional Information ◽

Mri Scans ◽

Study Methodology ◽

Acute Intracerebral Hemorrhage ◽

Magnetic Resonance Imaging Mri ◽

Suspected Stroke

This chapter, found in the headache section of the book, provides a succinct synopsis of a key study comparing the use of computed tomography (CT) and magnetic resonance imaging (MRI) scans for detecting acute intracerebral hemorrhage in stroke patients. This summary outlines the study methodology and design, major results, limitations and criticisms, related studies and additional information, and clinical implications. The researchers found that MRI is as accurate as CT for detecting acute hemorrhage in suspected stroke and is more accurate than CT for detecting chronic intracerebral hemorrhage. In addition to outlining the most salient features of the study, a clinical vignette and imaging example are included in order to provide relevant clinical context.

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Occupational Kneeling and Meniscal Tears: A Magnetic Resonance Imaging Study in Floor Layers

The Journal of Rheumatology ◽

10.3899/jrheum.081150 ◽

2009 ◽

Vol 36 (7) ◽

pp. 1512-1519 ◽

Cited By ~ 34

Author(s):

SØREN RYTTER ◽

LILLI KIRKESKOV JENSEN ◽

JENS PETER BONDE ◽

ANNE GRETHE JURIK ◽

NIELS EGUND

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Medial Meniscus ◽

Imaging Study ◽

Study Groups ◽

Meniscal Tears ◽

Resonance Imaging ◽

Logistic Regression Models ◽

Mri Scans ◽

Magnetic Resonance Imaging Mri

Objective.To evaluate the association between occupational kneeling and degenerative meniscal tears.Methods.Magnetic resonance imaging (MRI) of both knees was conducted in 92 male floor layers and 49 male graphic designers (referents), with a mean age of 55.6 years (range 42–70 yrs). The presence of grade 3 MRI signal intensities indicating degenerative tears of the anterior, middle, and posterior one-third of the lateral and medial menisci was assessed on 1.5-Tesla MRI scans. The odds ratio (OR) of meniscal tears was determined among floor layers compared to graphic designers. Using logistic regression, models were adjusted for age, body mass index, and knee-straining sports.Results.Degenerative tears were significantly more prevalent in the medial meniscus among floor layers than among graphic designers [OR 2.28, 95% confidence interval (CI) 1.10–4.98] and significantly more floor layers had medial tears in both knees (OR 3.46, 95% CI 1.41–8.48). Tears extending to the tibial aspect and localized in the middle and posterior one-third of the medial meniscus were most prevalent. Lateral meniscal tears were predominantly unilateral and the prevalence of lateral tears did not differ between the 2 study groups. Knee complaints occurred in about 50% of all floor layers, irrespective of the presence of meniscal tears.Conclusion.Occupational kneeling increases the risk of degenerative tears in the medial but not the lateral menisci in both knees.

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Prevalence of Cerebral Microbleeds in Thai Patients with Ischemic Stroke

Journal of Neurosciences in Rural Practice ◽

10.4103/0976-3147.203836 ◽

2017 ◽

Vol 08 (02) ◽

pp. 216-220 ◽

Cited By ~ 4

Author(s):

Artit Potigumjon ◽

Arvemas Watcharakorn ◽

Pornpatr A. Dharmasaroja

Keyword(s):

Ischemic Stroke ◽

White Matter ◽

Magnetic Resonance ◽

White Matter Lesions ◽

Cerebral Microbleeds ◽

National Institutes Of Health ◽

Asian Origin ◽

Chinese Study ◽

Japanese Studies ◽

Magnetic Resonance Imaging Mri

ABSTRACT Background: With the widespread use of magnetic resonance imaging (MRI), cerebral microbleeds (CMBs) are commonly detected. Ethnicity seems to play a role in the prevalence of CMB, with higher prevalence in participants from Asian origin. The purpose of the study is to look for the prevalence of CMBs and associated factors in Thai patients with ischemic stroke. Methods: Patients with acute ischemic stroke who had MRI and magnetic resonance angiography during January–August 2014 were included in the study. T2*-weighted gradient-recalled echo was used to define CMBs. Baseline characteristics, stroke subtypes, and severity of white matter lesions were compared between patients with and without CMBs. Results: Two hundred patients were included in the study. Mean age of the patients was 61-year-old. Mean National Institutes of Health Stroke Scale was 8. The prevalence of CMBs was 20% (39/200 patients). Hypertension (odds ratio [OR] 3.05, 95% confidence interval [CI] 1.07–8.68, P = 0.037), and moderate-to-severe white matter lesions (Fazekas 2–3, OR 7.61, 95% CI 3.06–18.95, P < 0.001) were related to the presence of CMBs. Conclusions: CMBs were found in 20% of patients with ischemic stroke, which was lower than those reported from Japanese studies but comparable to a Chinese study. CMBs were associated with hypertension and severity of the white matter lesions.

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Expert opinion paper on cardiac imaging after ischemic stroke

Clinical Research in Cardiology ◽

10.1007/s00392-021-01834-x ◽

2021 ◽

Author(s):

Renate B. Schnabel ◽

Stephan Camen ◽

Fabian Knebel ◽

Andreas Hagendorff ◽

Udo Bavendiek ◽

...

Keyword(s):

Ischemic Stroke ◽

Expert Opinion ◽

Cardiac Imaging ◽

Controlled Trial ◽

Case Series ◽

Stroke Care ◽

Imaging Method ◽

Cardiac Evaluation ◽

Magnetic Resonance Imaging Mri ◽

Ischemic Attack

AbstractThis expert opinion paper on cardiac imaging after acute ischemic stroke or transient ischemic attack (TIA) includes a statement of the “Heart and Brain” consortium of the German Cardiac Society and the German Stroke Society. The Stroke Unit-Commission of the German Stroke Society and the German Atrial Fibrillation NETwork (AFNET) endorsed this paper. Cardiac imaging is a key component of etiological work-up after stroke. Enhanced echocardiographic tools, constantly improving cardiac computer tomography (CT) as well as cardiac magnetic resonance imaging (MRI) offer comprehensive non- or less-invasive cardiac evaluation at the expense of increased costs and/or radiation exposure. Certain imaging findings usually lead to a change in medical secondary stroke prevention or may influence medical treatment. However, there is no proof from a randomized controlled trial (RCT) that the choice of the imaging method influences the prognosis of stroke patients. Summarizing present knowledge, the German Heart and Brain consortium proposes an interdisciplinary, staged standard diagnostic scheme for the detection of risk factors of cardio-embolic stroke. This expert opinion paper aims to give practical advice to physicians who are involved in stroke care. In line with the nature of an expert opinion paper, labeling of classes of recommendations is not provided, since many statements are based on expert opinion, reported case series, and clinical experience.

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Regional medical practice variation in high-cost healthcare services

The European Journal of Health Economics ◽

10.1007/s10198-021-01298-w ◽

2021 ◽

Author(s):

Michael Berger ◽

Thomas Czypionka

Keyword(s):

Medical Practice ◽

Regional Variation ◽

Multivariate Regression ◽

Healthcare Services ◽

Practice Variation ◽

District Level ◽

Healthcare Data ◽

Regional Medical ◽

Mri Scans ◽

Magnetic Resonance Imaging Mri

AbstractMagnetic resonance imaging (MRI) is a popular yet cost-intensive diagnostic measure whose strengths compared to other medical imaging technologies have led to increased application. But the benefits of aggressive testing are doubtful. The comparatively high MRI usage in Austria in combination with substantial regional variation has hence become a concern for its policy makers. We use a set of routine healthcare data on outpatient MRI service consumption of Austrian patients between Q3-2015 and Q2-2016 on the district level to investigate the extent of medical practice variation in a two-step statistical analysis combining multivariate regression models and Blinder–Oaxaca decomposition. District-level MRI exam rates per 1.000 inhabitants range from 52.38 to 128.69. Controlling for a set of regional characteristics in a multivariate regression model, we identify payer autonomy in regulating access to MRI scans as the biggest contributor to regional variation. Nevertheless, the statistical decomposition highlights that more than 70% of the regional variation remains unexplained by differences between the observable district characteristics. In the absence of epidemiological explanations, the substantial regional medical practice variation calls the efficiency of resource deployment into question.

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A detailed analysis of anatomical plausibility of crossed and uncrossed streamline rendition of the dentato-rubro-thalamic tract (DRT(T)) in a commercial stereotactic planning system

Acta Neurochirurgica ◽

10.1007/s00701-021-04890-4 ◽

2021 ◽

Author(s):

Volker A. Coenen ◽

Bastian E. Sajonz ◽

Peter C. Reinacher ◽

Christoph P. Kaller ◽

Horst Urbach ◽

...

Keyword(s):

Surgical Planning ◽

Ground Truth ◽

Planning System ◽

Single Subject ◽

Fiber Structure ◽

Native Space ◽

Volume Of Interest ◽

Mri Scans ◽

Magnetic Resonance Imaging Mri ◽

The Individual

Abstract Background An increasing number of neurosurgeons use display of the dentato-rubro-thalamic tract (DRT) based on diffusion weighted imaging (dMRI) as basis for their routine planning of stimulation or lesioning approaches in stereotactic tremor surgery. An evaluation of the anatomical validity of the display of the DRT with respect to modern stereotactic planning systems and across different tracking environments has not been performed. Methods Distinct dMRI and anatomical magnetic resonance imaging (MRI) data of high and low quality from 9 subjects were used. Six subjects had repeated MRI scans and therefore entered the analysis twice. Standardized DICOM structure templates for volume of interest definition were applied in native space for all investigations. For tracking BrainLab Elements (BrainLab, Munich, Germany), two tensor deterministic tracking (FT2), MRtrix IFOD2 (https://www.mrtrix.org), and a global tracking (GT) approach were used to compare the display of the uncrossed (DRTu) and crossed (DRTx) fiber structure after transformation into MNI space. The resulting streamlines were investigated for congruence, reproducibility, anatomical validity, and penetration of anatomical way point structures. Results In general, the DRTu can be depicted with good quality (as judged by waypoints). FT2 (surgical) and GT (neuroscientific) show high congruence. While GT shows partly reproducible results for DRTx, the crossed pathway cannot be reliably reconstructed with the other (iFOD2 and FT2) algorithms. Conclusion Since a direct anatomical comparison is difficult in the individual subjects, we chose a comparison with two research tracking environments as the best possible “ground truth.” FT2 is useful especially because of its manual editing possibilities of cutting erroneous fibers on the single subject level. An uncertainty of 2 mm as mean displacement of DRTu is expectable and should be respected when using this approach for surgical planning. Tractographic renditions of the DRTx on the single subject level seem to be still illusive.

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Brain atrophy and clinical characteristics predicting SDMT performance in multiple sclerosis: A 10-year follow-up study

Multiple Sclerosis Journal - Experimental Translational and Clinical ◽

10.1177/2055217321992394 ◽

2021 ◽

Vol 7 (1) ◽

pp. 205521732199239

Author(s):

Cecilie Jacobsen ◽

Robert Zivadinov ◽

Kjell-Morten Myhr ◽

Turi O Dalaker ◽

Ingvild Dalen ◽

...

Keyword(s):

Clinical Data ◽

Grey Matter Volume ◽

Lesion Volume ◽

Information Processing Speed ◽

Disability Status ◽

Mri Scans ◽

Patients At Risk ◽

Magnetic Resonance Imaging Mri ◽

Specific Volumes

Objectives To identify Magnetic Resonance Imaging (MRI), clinical and demographic biomarkers predictive of worsening information processing speed (IPS) as measured by Symbol Digit Modalities Test (SDMT). Methods Demographic, clinical data and 1.5 T MRI scans were collected in 76 patients at time of inclusion, and after 5 and 10 years. Global and tissue-specific volumes were calculated at each time point. For the primary outcome of analysis, SDMT was used. Results Worsening SDMT at 5-year follow-up was predicted by baseline age, Expanded Disability Status Scale (EDSS), SDMT, whole brain volume (WBV) and T2 lesion volume (LV), explaining 30.2% of the variance of SDMT. At 10-year follow-up, age, EDSS, grey matter volume (GMV) and T1 LV explained 39.4% of the variance of SDMT change. Conclusion This longitudinal study shows that baseline MRI-markers, demographic and clinical data can help predict worsening IPS. Identification of patients at risk of IPS decline is of importance as follow-up, treatment and rehabilitation can be optimized.

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Cross-sectional analysis of follow-up chest MRI and chest CT scans in patients previously affected by COVID-19

La radiologia medica ◽

10.1007/s11547-021-01390-4 ◽

2021 ◽

Author(s):

Martina Pecoraro ◽

Stefano Cipollari ◽

Livia Marchitelli ◽

Emanuele Messina ◽

Maurizio Del Monte ◽

...

Keyword(s):

Chest Ct ◽

Ct Scans ◽

Imaging Biomarker ◽

Cross Sectional ◽

Mri Scans ◽

Magnetic Resonance Imaging Mri ◽

Sectional Analysis ◽

Ct And Mri ◽

Interlobular Septal Thickening

Abstract Purpose The aim of the study was to prospectively evaluate the agreement between chest magnetic resonance imaging (MRI) and computed tomography (CT) and to assess the diagnostic performance of chest MRI relative to that of CT during the follow-up of patients recovered from coronavirus disease 2019. Materials and methods Fifty-two patients underwent both follow-up chest CT and MRI scans, evaluated for ground-glass opacities (GGOs), consolidation, interlobular septal thickening, fibrosis, pleural indentation, vessel enlargement, bronchiolar ectasia, and changes compared to prior CT scans. DWI/ADC was evaluated for signal abnormalities suspicious for inflammation. Agreement between CT and MRI was assessed with Cohen’s k and weighted k. Measures of diagnostic accuracy of MRI were calculated. Results The agreement between CT and MRI was almost perfect for consolidation (k = 1.00) and change from prior CT (k = 0.857); substantial for predominant pattern (k = 0.764) and interlobular septal thickening (k = 0.734); and poor for GGOs (k = 0.339), fibrosis (k = 0.224), pleural indentation (k = 0.231), and vessel enlargement (k = 0.339). Meanwhile, the sensitivity of MRI was high for GGOs (1.00), interlobular septal thickening (1.00), and consolidation (1.00) but poor for fibrotic changes (0.18), pleural indentation (0.23), and vessel enlargement (0.50) and the specificity was overall high. DWI was positive in 46.0% of cases. Conclusions The agreement between MRI and CT was overall good. MRI was very sensitive for GGOs, consolidation and interlobular septal thickening and overall specific for most findings. DWI could be a reputable imaging biomarker of inflammatory activity.

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