scholarly journals Accelerated 3D whole-brain T1, T2, and proton density mapping: feasibility for clinical glioma MR imaging

2021 ◽  
Author(s):  
Carolin M. Pirkl ◽  
Laura Nunez-Gonzalez ◽  
Florian Kofler ◽  
Sebastian Endt ◽  
Lioba Grundl ◽  
...  
Keyword(s):  
Tissue Characterization ◽  
Image Synthesis ◽  
Quantitative Information ◽  
Initial Assessment ◽  
Proton Density ◽  
Whole Brain ◽  
Density Mapping ◽  
Quantitative Mr ◽  
Scan Time ◽  
T1 And T2

Abstract Purpose Advanced MRI-based biomarkers offer comprehensive and quantitative information for the evaluation and characterization of brain tumors. In this study, we report initial clinical experience in routine glioma imaging with a novel, fully 3D multiparametric quantitative transient-state imaging (QTI) method for tissue characterization based on T1 and T2 values. Methods To demonstrate the viability of the proposed 3D QTI technique, nine glioma patients (grade II–IV), with a variety of disease states and treatment histories, were included in this study. First, we investigated the feasibility of 3D QTI (6:25 min scan time) for its use in clinical routine imaging, focusing on image reconstruction, parameter estimation, and contrast-weighted image synthesis. Second, for an initial assessment of 3D QTI-based quantitative MR biomarkers, we performed a ROI-based analysis to characterize T1 and T2 components in tumor and peritumoral tissue. Results The 3D acquisition combined with a compressed sensing reconstruction and neural network-based parameter inference produced parametric maps with high isotropic resolution (1.125 × 1.125 × 1.125 mm3 voxel size) and whole-brain coverage (22.5 × 22.5 × 22.5 cm3 FOV), enabling the synthesis of clinically relevant T1-weighted, T2-weighted, and FLAIR contrasts without any extra scan time. Our study revealed increased T1 and T2 values in tumor and peritumoral regions compared to contralateral white matter, good agreement with healthy volunteer data, and high inter-subject consistency. Conclusion 3D QTI demonstrated comprehensive tissue assessment of tumor substructures captured in T1 and T2 parameters. Aiming for fast acquisition of quantitative MR biomarkers, 3D QTI has potential to improve disease characterization in brain tumor patients under tight clinical time-constraints.

Fast whole brain quantitative proton density mapping to quantify metabolites in tumors

2013 ◽  
Vol 29 ◽  
pp. e11-e12
Author(s):  
A. Lecocq ◽  
Y. Le Fur ◽  
A. Amadon ◽  
A. Vignaud ◽  
M. Bernard ◽  
...  
Keyword(s):  
Proton Density ◽  
Whole Brain ◽  
Density Mapping

Abstract TP219: Eight-minute Whole-brain Intracranial Vessel Wall MRI at 3 Tesla: Toward a Practical Imaging Protocol for Diagnosis of Stroke Etiology

Stroke ◽  
2016 ◽  
Vol 47 (suppl_1) ◽  
Author(s):  
Zhaoyang Fan ◽  
Qi Yang ◽  
Shlee Song ◽  
Xiuhai Guo ◽  
Zixin Deng ◽  
...  
Keyword(s):  
Pilot Study ◽  
Healthy Subjects ◽  
Vessel Wall ◽  
3 Tesla ◽  
Whole Brain ◽  
Imaging Protocol ◽  
Stroke Etiology ◽  
Intracranial Vessel ◽  
Scan Time ◽  
T1 And T2

Introduction: T1-weighted variable-flip-angle 3D turbo spin-echo (TSE), has emerged as a vessel wall MRI technique promising for elucidating underlying intracranial vessel wall pathologies associated with stroke. Whole-brain 0.5-mm isotropic-resolution 3D TSE has recently been proposed at 3 Tesla. However, its scan time of 12 min renders it impractical for a clinical setting. This work aimed to design an expedited protocol and conduct a pilot study to demonstrate its potential for diagnosis of wall abnormalities. Methods: To expedite the acquisition, one may exploit an elliptical data sampling strategy and prolonged echo train length (ETL). However, this would reduce image SNR and compromise vessel wall delineation. On the other hand, SNR is intimately related to refocusing flip angles that are calculated for a prescribed tissue with specific T1 and T2 values (denoted as simulation T1 and T2). In this work, the effects of simulation T2 and ETL on the SNR/CNR performance were first explored on 9 healthy subjects. An optimized imaging protocol was then determined from a narrowed range of choices on 7 healthy subjects and finally applied to a pilot study of 10 patients with known wall disease. Results: Wall SNR, wall-CSF CNR, and white-gray matter CNR generally increased with simulation T2 and decreased with ETL. Optimization was focused on a narrowed range of protocol choices (ETL = 52; T2 = 140, 170, 200 ms) which enable a scan time of 8 min. ETL=52/T2=170ms was shown (Figure a.) to provide significantly higher (t-test) SNR/CNR performance than the original 12-min protocol (ETL=36/T2=100ms). With the 8-min protocol pre/post contrast, wall abnormalities (Figure b.) were correctly detected in all patients. Conclusion: An 8-min whole-brain intracranial vessel wall imaging protocol is developed which has demonstrated the potential of accurately identifying various wall abnormalities. A large-scale trial on using the technique for diagnosis of stroke etiology is underway.

Cardiac tissue characterization with t1 and t2 mapping in anderson fabry patients: new pathophysiological concepts and early cardiac involvement

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
R Zanoni ◽  
V Ferrara ◽  
G Lanati ◽  
G Vitale ◽  
F Di Nicola ◽  
...  
Keyword(s):  
Cardiac Disease ◽  
Tissue Characterization ◽  
Cardiac Involvement ◽  
Late Onset ◽  
T2 Mapping ◽  
Serum Levels ◽  
Left Ventricular ◽  
Control Group ◽  
Funding Source ◽  
T1 And T2

Abstract Background Anderson Fabry (AF) disease is a X-linked lysosomal storage disorder with multiorgan involvement. Cardiac disease, mainly represented by left ventricular hypertrophy (LVH) and arrhythmias, is the most frequent cause of premature death. It is well know that specific therapy is less effective after the development of LVH and myocardial fibrosis, therefore early cardiac detection (before LVH) is important. New cardiac magnetic resonance (CMR) parametric imaging techniques (T1 and T2 maps) enable myocardial tissue changes associated with AF disease. Purpose To evaluate the relationship between CMR tissue characterization and clinical and instrumental manifestations of AF disease to find early markers of cardiac involvement. Methods 31 AF patients (9 males, mean age 49±16 years) underwent ECG, echocardiogram and contrast CMR. TnI, BNP, pro-BNP and serum lyso-Gb3 were dosed. T1 mapping was performed in a pre-contrast acquisition with the modified Look-Locker inversion recovery (MOLLI) sequences. CMR results were compared with those of 43 healthy age and gender-matched controls. Results In AF patients native septal T1 values were significantly lower compared to healthy controls (median 949 vs 991 msec, p=0.0137) and were inversely related to Lyso-Gb3 serum levels (p=0.003). Patients with LVH had lower T1 septal values in comparison with patients without LVH (892 vs 981 msec; p=0.0012). Patients with classic form had abnormal low T1 values more frequently than pts with late onset variant (78 vs 23%; p=0.038). In AF patients native septal T2 values were significantly higher compared to the control group (53 vs 49 msec; p=0.0004) and correlated with troponin I (p=0.008) and NT-pro BNP (p=0.006) serum levels. No difference was found between pts with and without LVH (53.5 vs 52.5 ms; p=0.797) and the prevalence of abnormal high T2 values was similar between patients with late onset AF and pts with classical form (53% vs 50%; p=1.000). All patients with late onset AF and high T2 values were females. Conclusions CMR T1 (low values) and T2 (high values) mapping are useful tools to detect early cardiac involvement before LVH and to better understand the pathophysiology of cardiac disease in AF patients. Subclinical tissue inflammation, detectable through T2 maps, seems to be an additional pathogenetic mechanism related to the Gb3 storage that contributes to organ damage and precedes LVH, particularly in females patients with late onset phenotype. Funding Acknowledgement Type of funding source: Public hospital(s). Main funding source(s): Sant'Orsola-Malpighi Hospital

scholarly journals Cardiac magnetic resonance imaging in differential diagnosis of cardiac masses

2021 ◽  
Vol 22 (Supplement_1) ◽  
Author(s):  
EC D"angelo ◽  
P Paolisso ◽  
L Bergamaschi ◽  
A Foa ◽  
I Magnani ◽  
...  
Keyword(s):  
Differential Diagnosis ◽  
Cardiac Magnetic Resonance ◽  
Magnetic Resonance ◽  
Pericardial Effusion ◽  
Tissue Characterization ◽  
Descriptive Analysis ◽  
Gadolinium Enhancement ◽  
Malignant Lesions ◽  
T1 And T2 ◽  
Cardiac Masses

Abstract Funding Acknowledgements Type of funding sources: Public hospital(s). Main funding source(s): S. Orsola Hospital Background  Differential diagnosis of cardiac masses represents a challenging issue with important implications for therapeutic management and patient’s prognosis. Cardiac Magnetic Resonance (CMR) is a non-invasive imaging technique used to characterize morphologic and functional features of masses. Integration of these information can lead an accurate diagnosis. Purpose  To evaluate the diagnostic role of CMR in defining the nature of cardiac masses. Methods : Ninety-three patients with cardiac masses evaluated with CMR were enrolled. All masses had histological certainty. CMR sequences allowed a qualitative morphologic description as well as tissue characterization. Evaluation of masses morphology included localization, size and borders assessment, detection of potential multiple lesions and pericardial effusion. Tissue characterization resulted from an estimation of contrast enhancement - early gadolinium enhancement (EGE) and late gadolinium enhancement (LGE) sequences - and tissue homogeneity in T1 and T2 weighted acquisitions. The descriptive analysis was carried out by comparing benign vs malignant lesions as well as dividing patients into 4 subgroups: primitive benign tumours, primitive malignant tumours, metastatic tumours and pseudotumours.  Results  The descriptive analysis of the morphologic features showed that diameter > 50mm, invasion of surrounding planes, irregular margins and presence of pericardial effusion were able to predict malignancy (p < 0.001). As for tissue characteristics, heterogeneous signal intensity - independently from T1 and T2 weighted acquisitions - and EGE were more common in malignant lesions (p <0.001). When analysing the four subgroups, CMR features did not discriminate between primitive malignant masses and metastasis. Conversely, hyperintensity signal and EGE were able to distinguish benign primitive lesions from pseudotumors (p = 0.002).  Furthermore, using classification and regression tree (CART) analysis, we developed an algorithm to differentiate masses: invasion of surrounding planes was a common characteristic of malignancy and identifies itself malignant tumors. In the absence of invasive features, gadolinium enhancement was evaluated: the lack of contrast uptake was able to exclude a pseudotumor diagnosis and reduced the probability of a primary benign tumor.  Conclusions Cardiac magnetic resonance is a very powerful diagnostic tool for differential diagnosis of cardiac masses as it correctly addresses malignancy. Furthermore, an accurate evaluation of the several CMR features, may discriminate primary benign masses and pseudotumours. Abstract Figure. Benign and malignant cardiac masses

Quantitative T 1 and proton density mapping with direct calculation of radiofrequency coil transmit and receive profiles from two-point variable flip angle data

2016 ◽  
Vol 29 (3) ◽  
pp. 349-360 ◽  
Author(s):  
Simon Baudrexel ◽  
Sarah C. Reitz ◽  
Stephanie Hof ◽  
René-Maxime Gracien ◽  
Vinzenz Fleischer ◽  
...  
Keyword(s):  
Direct Calculation ◽  
Flip Angle ◽  
Proton Density ◽  
Variable Flip Angle ◽  
Density Mapping ◽  
Radiofrequency Coil ◽  
Angle Data

scholarly journals Myocardial Mapping in Systemic Sarcoidosis: A Comparison of Two Measurement Approaches

2020 ◽  
Vol 193 (01) ◽  
pp. 68-76
Author(s):  
Darius Dabir ◽  
Julian Luetkens ◽  
Daniel Kuetting ◽  
Jennifer Nadal ◽  
Hans Heinz Schild ◽  
...  
Keyword(s):  
T1 Mapping ◽  
Tissue Characterization ◽  
Cardiac Involvement ◽  
T2 Mapping ◽  
Relaxation Times ◽  
Short Axis Slice ◽  
T2 Relaxation ◽  
Standard Mapping ◽  
Systemic Sarcoidosis ◽  
T1 And T2

Purpose To investigate if T1 and T2 mapping is able to differentiate between diseased and healthy myocardium in patients with systemic sarcoidosis, and to compare the standard mapping measurement (measurement within the whole myocardium of the midventricular short axis slice, SAX) to a more standardized method measuring relaxation times within the midventricular septum (ConSept). Materials and Methods 24 patients with biopsy-proven extracardiac sarcoidosis and 17 healthy control subjects were prospectively enrolled in this study and underwent CMR imaging at 1.5 T including native T1 and T2 mapping. Patients were divided into patients with (LGE+) and without (LGE–) cardiac sarcoidosis. T1 and T2 relaxation times were compared between patients and controls. Furthermore, the SAX and the ConSept approach were compared regarding differentiation between healthy and diseased myocardium. Results T1 and T2 relaxation times were significantly longer in all patients compared with controls using both the SAX and the ConSept approach (p < 0.05). However, LGE+ and LGE– patients showed no significant differences in T1 and T2 relaxation times regardless of the measurement approach used (ConSept/SAX) (p > 0.05). Direct comparison of ConSept and SAX T1 mapping showed high conformity in the discrimination between healthy and diseased myocardium (Kappa = 0.844). Conclusion T1 and T2 mapping may not only enable noninvasive recognition of cardiac involvement in patients with systemic sarcoidosis but may also serve as a marker for early cardiac involvement of the disease allowing for timely treatment. ConSept T1 mapping represents an equivalent method for tissue characterization in this population compared to the SAX approach. Further studies including follow-up examinations are necessary to confirm these preliminary results. Key Points:  Citation Format

scholarly journals Whole brain myelin mapping using T1- and T2-weighted MR imaging data

2014 ◽  
Vol 8 ◽  
Author(s):  
Marco Ganzetti ◽  
Nicole Wenderoth ◽  
Dante Mantini
Keyword(s):  
Mr Imaging ◽  
Imaging Data ◽  
Whole Brain ◽  
T1 And T2

scholarly journals A new algebraic method for quantitative proton density mapping using multi-channel coil data

2017 ◽  
Vol 40 ◽  
pp. 154-171 ◽  
Author(s):  
Dietmar Cordes ◽  
Zhengshi Yang ◽  
Xiaowei Zhuang ◽  
Karthik Sreenivasan ◽  
Virendra Mishra ◽  
...  
Keyword(s):  
Algebraic Method ◽  
Proton Density ◽  
Density Mapping ◽  
Channel Coil

scholarly journals ADvanced IMage Algebra (ADIMA): a novel method for depicting multiple sclerosis lesion heterogeneity, as demonstrated by quantitative MRI

2012 ◽  
Vol 19 (6) ◽  
pp. 732-741 ◽  
Author(s):  
Marios C Yiannakas ◽  
Daniel J Tozer ◽  
Klaus Schmierer ◽  
Declan T Chard ◽  
Valerie M Anderson ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Magnetic Resonance ◽  
Quantitative Mri ◽  
Multiple Sclerosis Lesion ◽  
Proton Density ◽  
Image Algebra ◽  
Quantitative Magnetic Resonance ◽  
Magnetic Resonance Parameters ◽  
Mri Scans ◽  
T1 And T2

Background: There are modest correlations between multiple sclerosis (MS) disability and white matter lesion (WML) volumes, as measured by T2-weighted (T2w) magnetic resonance imaging (MRI) scans (T2-WML). This may partly reflect pathological heterogeneity in WMLs, which is not apparent on T2w scans. Objective: To determine if ADvanced IMage Algebra (ADIMA), a novel MRI post-processing method, can reveal WML heterogeneity from proton-density weighted (PDw) and T2w images. Methods: We obtained conventional PDw and T2w images from 10 patients with relapsing–remitting MS (RRMS) and ADIMA images were calculated from these. We classified all WML into bright (ADIMA-b) and dark (ADIMA-d) sub-regions, which were segmented. We obtained conventional T2-WML and T1-WML volumes for comparison, as well as the following quantitative magnetic resonance parameters: magnetisation transfer ratio (MTR), T1 and T2. Also, we assessed the reproducibility of the segmentation for ADIMA-b, ADIMA-d and T2-WML. Results: Our study’s ADIMA-derived volumes correlated with conventional lesion volumes ( p < 0.05). ADIMA-b exhibited higher T1 and T2, and lower MTR than the T2-WML ( p < 0.001). Despite the similarity in T1 values between ADIMA-b and T1-WML, these regions were only partly overlapping with each other. ADIMA-d exhibited quantitative characteristics similar to T2-WML; however, they were only partly overlapping. Mean intra- and inter-observer coefficients of variation for ADIMA-b, ADIMA-d and T2-WML volumes were all < 6 % and < 10 %, respectively. Conclusion: ADIMA enabled the simple classification of WML into two groups having different quantitative magnetic resonance properties, which can be reproducibly distinguished.

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