scholarly journals Native T1 Mapping and Magnetization Transfer Imaging in Grading Bowel Fibrosis in Crohn’s Disease: A Comparative Animal Study

Biosensors ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 302
Author(s):  
Baolan Lu ◽  
Jinjiang Lin ◽  
Jinfang Du ◽  
Shaofu He ◽  
Qinghua Cao ◽  
...  
Keyword(s):  
Diagnostic Performance ◽  
T1 Mapping ◽  
Magnetization Transfer ◽  
Area Under The Curve ◽  
Imaging Biomarker ◽  
Magnetization Transfer Ratio ◽  
Magnetization Transfer Imaging ◽  
Longitudinal Relaxation Time ◽  
Native T1 ◽  
Severe Fibrosis

In this study, we investigated the utility of native T1 mapping in differentiating between various grades of fibrosis and compared its diagnostic accuracy to magnetization transfer imaging (MTI) in a rat model of CD. Bowel specimens (64) from 46 CD model rats undergoing native T1 mapping and MTI were enrolled. The longitudinal relaxation time (T1 value) and normalized magnetization transfer ratio (MTR) were compared between none-to-mild and moderate-to-severe fibrotic bowel walls confirmed by pathological assessments. The results showed that the correlation between the T1 value and fibrosis (r = 0.438, p < 0.001) was lower than that between the normalized MTR and fibrosis (r = 0.623, p < 0.001). Overall, the T1 values (t = −3.066, p = 0.004) and normalized MTRs (z = 0.081, p < 0.001) in none-to-mild fibrotic bowel walls were lower than those in moderate-to-severe fibrotic bowel walls. The area under the curve (AUC) of the T1 value (AUC = 0.716, p = 0.004) was significantly lower than that of the normalized MTR (AUC = 0.881, p < 0.001) in differentiating moderate-to-severe fibrosis from none-to-mild fibrosis (z = −2.037, p = 0.042). Our results support the view that the T1 value could be a promising imaging biomarker in grading the fibrosis severity of CD. However, the diagnostic performance of native T1 mapping was not superior to MTI.

scholarly journals Differential Progression of Magnetization Transfer Imaging Changes Depending on Severity of Cerebral Hypoxic-Ischemic Injury

2008 ◽  
Vol 28 (9) ◽  
pp. 1613-1623 ◽  
Author(s):  
Ursula I Tuor ◽  
Shuzhen Meng ◽  
Min Qiao ◽  
Nicole B Webster ◽  
Shauna M Crowley ◽  
...  
Keyword(s):  
White Matter ◽  
Magnetization Transfer ◽  
Ischemic Injury ◽  
Subcortical White Matter ◽  
Cerebral Injury ◽  
Magnetization Transfer Ratio ◽  
Magnetization Transfer Imaging ◽  
Cerebral Hypoxia ◽  
Hypoxia Ischemia ◽  
Hypoxic Ischemic Injury

We hypothesized that magnetic resonance magnetization transfer (MT) imaging would be sensitive for detecting cerebral ischemic injury in white matter of neonatal brain. We compared the progression of changes in T2 and the MT ratio (MTR) after cerebral hypoxic-ischemic insults of differing severity in neonatal rats. Magnetization transfer imaging parameters were first optimized, and then MTR and T2 maps were acquired at various times after a mild (rather selective white matter) or substantial insult produced by unilateral cerebral hypoxia—ischemia. Depending on insult severity, time after insult, and region (e.g., subcortical white matter or cortex), cerebral hypoxia—ischemia produced reductions in MTR and an increase in T2. The exception was acutely at 1 to 5 h at which time points MTR was reduced ipsilaterally in white matter, whereas T2 was not affected significantly. Progression of imaging changes differed in rats grouped according to whether gross damage was present after chronic recovery. Behavioral changes were generally associated with chronic reductions in MTR and gross brain damage. Magnetization transfer imaging was capable of early detection of hypoxic-ischemic injury and particularly sensitive for identifying the progression of cerebral injury in white matter. Magnetization transfer ratio has potential for assisting with early diagnosis and treatment assessment for infants affected by perinatal hypoxia—ischemia.

scholarly journals Reliability and reproducibility of sciatic nerve magnetization transfer imaging and T2 relaxometry

2021 ◽  
Author(s):  
Fabian Preisner ◽  
Rouven Behnisch ◽  
Olivia Foesleitner ◽  
Daniel Schwarz ◽  
Michaela Wehrstein ◽  
...  
Keyword(s):  
Sciatic Nerve ◽  
Magnetization Transfer ◽  
Proton Spin ◽  
Magnetization Transfer Ratio ◽  
Magnetization Transfer Imaging ◽  
Correct Interpretation ◽  
T2 Relaxometry ◽  
Retest Reliability ◽  
Future Studies ◽  
Test Retest Reliability

Abstract Objectives To assess the interreader and test-retest reliability of magnetization transfer imaging (MTI) and T2 relaxometry in sciatic nerve MR neurography (MRN). Materials and methods In this prospective study, 21 healthy volunteers were examined three times on separate days by a standardized MRN protocol at 3 Tesla, consisting of an MTI sequence, a multi-echo T2 relaxometry sequence, and a high-resolution T2-weighted sequence. Magnetization transfer ratio (MTR), T2 relaxation time, and proton spin density (PSD) of the sciatic nerve were assessed by two independent observers, and both interreader and test-retest reliability for all readout parameters were reported by intraclass correlation coefficients (ICCs) and standard error of measurement (SEM). Results For the sciatic nerve, overall mean ± standard deviation MTR was 26.75 ± 3.5%, T2 was 64.54 ± 8.2 ms, and PSD was 340.93 ± 78.8. ICCs ranged between 0.81 (MTR) and 0.94 (PSD) for interreader reliability and between 0.75 (MTR) and 0.94 (PSD) for test-retest reliability. SEM for interreader reliability was 1.7% for MTR, 2.67 ms for T2, and 21.3 for PSD. SEM for test-retest reliability was 1.7% for MTR, 2.66 ms for T2, and 20.1 for PSD. Conclusions MTI and T2 relaxometry of the sciatic nerve are reliable and reproducible. The values of measurement imprecision reported here may serve as a guide for correct interpretation of quantitative MRN biomarkers in future studies. Key Points • Magnetization transfer imaging (MTI) and T2 relaxometry of the sciatic nerve are reliable and reproducible. • The imprecision that is unavoidably associated with different scans or different readers can be estimated by the here presented SEM values for the biomarkers T2, PSD, and MTR. • These values may serve as a guide for correct interpretation of quantitative MRN biomarkers in future studies and possible clinical applications.

scholarly journals A Novel Classification Method using Effective Neural Network and Quantitative Magnetization Transfer Imaging of Brain White Matter in Relapsing Remitting Multiple Sclerosis

2018 ◽  
Vol 8 (4Dec) ◽  
Author(s):  
M Fooladi ◽  
H Sharini ◽  
S Masjoodi ◽  
E Khodamoradi
Keyword(s):  
Neural Network ◽  
Multiple Sclerosis ◽  
Relaxation Time ◽  
Healthy Subjects ◽  
Magnetization Transfer ◽  
Magnetization Transfer Imaging ◽  
Longitudinal Relaxation Time ◽  
Brain White Matter ◽  
Relapsing Remitting ◽  
Relapsing Remitting Multiple Sclerosis

Background: Quantitative Magnetization Transfer Imaging (QMTI) is often used to quantify the myelin content in multiple sclerosis (MS) lesions and normal appearing brain tissues. Also, automated classifiers such as artificial neural networks (ANNs) can significantly improve the identification and classification processes of MS clinical datasets.Objective: We classified patients with relapsing-remitting multiple sclerosis (RRMS) from healthy subjects using QMTI and T1 longitudinal relaxation time data of brain white matter and the performance of three ANN-based classifiers have been investigated.   Materials and Methods: Conventional magnetic resonance imaging (MRI) and quantitative magnetization transfer scans were obtained from RRMS patients (n=30) and age-matched healthy subjects (n=30). After image pre-processing and brain tissue segmentation, QMTI parameters including magnetization transfer ratio (MTR), magnetization transfer rate (Ksat), T1 relaxation time under MT saturation pulse (T1sat) and T1 longitudinal relaxation time were calculated as parametric maps. Three ANN algorithms, including multilayer perceptron (MLP), radial basis function (RBF) and ensemble neural network based on Akaike information criterion (ENN-AIC) input features were extracted in the form of QMTI and T1 mean values. The ANNs quantitative performance is measured by the standard evaluation of confusion matrix criteria.Results: The results indicate that ENN-AIC-based classification method has achieved 90% accuracy, 92% sensitivity and 86% precision compared to other ANN classification models such as RBF and MLP. NPV, FPR and FDR values of the proposed ENN-AIC model were found to be 0.933, 0.125 and 0.133, respectively. A graphical representation of how to track actual data by the predictive values derived from each of the three algorithms, was also presented. It has been demonstrated that ENN-AIC as an effective neural network improves the quality of classification results compared to MLP and RBF.Conclusion: The efficiency and robustness of ENN classifier will greatly enhance with the use of AIC-based combination weights assignment. In addition, this research  provides a new direction to classify a large amount of quantitative MRI data that can help the physician in a correct MS diagnosis.

Contribution of cervical cord MRI and brain magnetization transfer imaging to the assessment of individual patients with multiple sclerosis: a preliminary study

2002 ◽  
Vol 8 (1_suppl) ◽  
pp. 52-58 ◽  
Author(s):  
M. Rovaris ◽  
M. Holtmannspötter ◽  
MA Rocca ◽  
G. Iannucci ◽  
M. Codella ◽  
...  
Keyword(s):  
Multiple Sclerosis ◽  
Lupus Erythematosus ◽  
Magnetization Transfer ◽  
False Negative ◽  
Brain Magnetic Resonance Imaging ◽  
Cervical Cord ◽  
Magnetization Transfer Ratio ◽  
Magnetization Transfer Imaging ◽  
Mri Scans ◽  
The Brain

This study was performed to assess how established diagnostic criteria for brain magnetic resonance imaging (MRI) interpretation in cases of suspected multiple sclerosis (MS) (Barkhofs criteria) would perform in the distinction of MS from other diseases and whether other MR techniques (cervical cord imaging and brain magnetization transfer imaging [MTI]), might help in the diagnostic work-up of these patients. We retrospectively identified 64 MS and 59 non-MS patients. The latter group included patients with systemic immune-mediated disorders (SID; n=44) and migraine (n=15). All patients had undergone MRI scans of the brain (dual echo and MTI) and of the cervical cord (fast short-tau inversion recovery). The number and location of brain T2-hyperintense lesions and the number and size of cervical cord lesions were assessed. Brain images were also postprocessed to quantify the total lesion volumes (TLV) and to create histograms of magnetization transfer ratio (MTR) values from the whole of the brain tissue. Barkhofs criteria correctly classified 108/123 patients, thus showing an accuracy of 87.8%. "False negative" MS patients were 13, while 2 patients with systemic lupus erythematosus (SLE) were considered as "false positives". Using brain T2 TLV, nine of the"false negative" patients were correctly classified. Correct classification of 10 MS patients and both the SLE patients was possible based upon the presence or absence of one cervical cord lesion. Two MS patients with negative Barkhofs criteria and no cervical cord lesions were correctly classified based on their brain MTR values. Overall, only one MS patient could not be correctly classified by any of the assessed MR quantities. These preliminary data support a more extensive use of cervical cord MRI and brain MTI to differentiate between MS and other disorders in case of inconclusive findings on T2-weighted MRI scans of the brain. Multiple Sclerosis (2002) 8, 52-58

scholarly journals Assessment of Cardiac Involvement in Fabry Disease (FD) with Native T1 Mapping

2019 ◽  
Vol 191 (10) ◽  
pp. 932-939
Author(s):  
Fritz Christian Roller ◽  
Sven Fuest ◽  
Marco Meyer ◽  
Sebastian Harth ◽  
Dursun Gündüz ◽  
...  
Keyword(s):  
Fabry Disease ◽  
T1 Mapping ◽  
Cardiac Involvement ◽  
Morphological Changes ◽  
Tissue Level ◽  
Therapeutic Benefit ◽  
Left Ventricular ◽  
Imaging Biomarker ◽  
Native T1 ◽  
Native T1 Time

Purpose Fabry disease (FD) is an X-linked multi-organ disorder of lysosomal metabolism with cardiac disease being the leading cause of death. Identifying early FD-specific pathologies is important in the context of maximum therapeutic benefit in these stages. Therefore, the aim of this study was to investigate the value of quantitative cardiac T1 mapping as a potential disease-specific surrogate. Methods 16 consecutive FD patients (9 female, 7 male; median age: 54 years, IQR 17) and 16 control patients (9 female, 7 male; median age: 52 years, IQR 20) were investigated at 1.5 Tesla. Native T1 mapping was performed using a modified look locker inversion recovery sequence (MOLLI) and native T1 times were measured within the septal myocardium at the midventricular short-axis section. Also functional parameters, left ventricular morphology, presence of late-gadolinium enhancement, cTnI- and Lyso-Gb3-Levels were evaluated. Results The median native septal T1 time for FD was 889.0 ms and 950.6 ms for controls (p < 0.003). LGE and positive cTnI values (0.26 ± 0.21) were present in 5 FD patients (31.25 %), and left ventricular hypertrophy (LVH) was present in 4 FD patients (25.00 %). The 4 cTnI and 8 Lyso-Gb3 positive FD patients had significantly lower native T1 values (p < 0.05, respectively p < 0.01). Assuming a T1 cut-off value of 900 ms for the identification of increased cardiac lipid deposit, 9 patients with FD (56.25 %) had pathologic values (4 patients cTnI and 8 patients Lyso-Gb3 positive). Moreover, native septal T1 showed a good negative correlation to Lyso-Gb3 (r = – 0.582; p = 0.018). Conclusion A pathologic cardiac native T1 time obviously reflects cardiac involvement in the scope of FD at tissue level. In the future native T1 mapping as an imaging biomarker might allow identification of early stages of cardiac involvement in FD before morphological changes are obvious. Key Points:  Citation Format

Optic nerve magnetization transfer imaging and measures of axonal loss and demyelination in optic neuritis

2007 ◽  
Vol 13 (7) ◽  
pp. 875-879 ◽  
Author(s):  
SA Trip ◽  
PG Schlottmann ◽  
SJ Jones ◽  
W-Y. Li ◽  
DF Garway-Heath ◽  
...  
Keyword(s):  
Optic Nerve ◽  
Optic Neuritis ◽  
Magnetization Transfer ◽  
Quantitative Information ◽  
Magnetization Transfer Ratio ◽  
Central Field ◽  
Axonal Loss ◽  
Magnetization Transfer Imaging ◽  
Vep Latency

Magnetization transfer imaging is an MRI technique that provides quantitative information about in vivo tissue integrity, including myelin and axonal content, and is expressed as the magnetization transfer ratio (MTR). The optic neuritis lesion can model the MS lesion in vivo and permits use of non-invasive markers of optic nerve myelination (visual evoked potential [VEP] latency) and retinal neuroaxonal loss (optical coherence tomography [OCT]) to provide further information about the in vivo substrates of optic nerve MTR. Twenty-five patients with optic neuritis were studied using an optic nerve MTR sequence, quantitative visual function testing, VEPs and OCT, along with 15 controls. MTR was reduced in affected nerves compared to both clinically unaffected nerves from patients and control nerves ( P < 0.001). Whole-nerve MTR correlated modestly with central-field VEP latency but more strongly when lesion-only MTR was measured, when a modest correlation with whole-field VEP latency emerged. OCT-quantified retinal neuroaxonal loss also correlated with MTR. In conclusion, markers of optic nerve myelination and axonal loss both correlate with optic nerve MTR. Because axonal loss following optic neuritis also results in myelin loss, the relative contributions of the two pathological conditions to the MTR measures cannot be estimated from this study. Multiple Sclerosis 2007; 13: 875—879. http://msj.sagepub.com

Ruling in or out the presence of cardiac amyloidosis based on cut-off values using T1-mapping – caution is required regarding the control group

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
D Korthals ◽  
G Chatzantonis ◽  
M Bietenbeck ◽  
C Meier ◽  
A Florian ◽  
...  
Keyword(s):  
Predictive Value ◽  
Cardiac Amyloidosis ◽  
T1 Mapping ◽  
Area Under The Curve ◽  
Diagnostic Algorithm ◽  
Cine Imaging ◽  
Control Group ◽  
Healthy Controls ◽  
Post Contrast ◽  
Native T1

Abstract Background Cardiac amyloidosis (CA) is an infiltrative disease that is characterized by accumulation of amyloid deposits in the interstitium of the myocardium. In contrast, hypertrophic cardiomyopathy (HCM) is caused by a disorganized arrangement of myocyte hypertrophy as well as expanded extracellular matrix, composed of interstitial and replacement fibrosis. Purpose A diagnostic algorithm based on (native) T1-mapping using cardiovascular magnetic resonance (CMR) was suggested in a recent study for the diagnosis of CA: A native T1 &lt;1,036ms was mentioned to have a 98% negative predictive value (NPV) for ruling out CA whereas a native T1 &gt;1,164ms showed a 98% positive predictive value (PPV) for the presence of CA. In the present study, we critically addressed the calculation of such cut-off values considering possible differences in the composition of the control group. Methods N=30 patients with CA, N=20 patients with HCM and N=15 healthy controls without relevant cardiac disease underwent dedicated CMR studies on a 1.5-T MR scanner. The CMR protocol comprised standard sequences for cine-imaging, native and post-contrast MOLLI-based T1-mapping and late-gadolinium-enhancement (LGE). ECV measurements were based on pre- and post-contrast T1-mapping images. Results Native T1 and ECV were significantly increased in CA compared to HCM and receiver operating characteristic (ROC) analyses revealed an area-under-the-curve (AUC) = 0.984 for native T1 (p&lt;0.001) and AUC = 0.985 for ECV (p&lt;0.001) regarding the diagnosis of CA). When CA patients were compared to HCM patients (excluding healthy controls), a native T1 &lt;1,036ms or an ECV &lt;33% were associated with a 99% NPV for ruling out CA whereas a native T1 ≥1,082ms or an ECV ≥41% were associated with a 99% PPV for diagnosis of CA. However, when CA patients were compared to healthy controls (excluding HCM patients), a native T1 &lt;1,025ms or an ECV &lt;34% were associated with a 99% NPV for ruling out CA whereas a native T1 ≥1,025ms or an ECV ≥34% were associated with a 99% PPV for diagnosis of CA since there was no overlap in native T1 and ECV values between CA patients and healthy controls. Conclusion Cut-off values for native T1 or ECV derived from ROC analyses (in a specific group of study patients) for ruling in or out the presence of CA are – amongst others - determined by the native T1 and ECV values of the respective “control group”. A different composition of the control group (e.g. HCM patients vs. healthy volunteers) will result in different cut-off values. Hence, previously suggested cut-off values obtained in single center studies need to be considered carefully – with a special attention to the control group of the underlying study – and should not be transferred to other centers carelessly. Funding Acknowledgement Type of funding source: None

scholarly journals Non-contrast myocardial infarct scar assessment using a hybrid native T1 and magnetization transfer imaging sequence at 1.5T

2018 ◽  
Vol 81 (5) ◽  
pp. 3192-3201 ◽  
Author(s):  
Chong Duan ◽  
Yanjie Zhu ◽  
Jihye Jang ◽  
Jennifer Rodriguez ◽  
Ulf Neisius ◽  
...  
Keyword(s):  
Myocardial Infarct ◽  
Magnetization Transfer ◽  
Magnetization Transfer Imaging ◽  
Native T1 ◽  
Scar Assessment ◽  
Imaging Sequence
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