scholarly journals Noninvasive stratification of postinfarction rats based on the degree of cardiac dysfunction using magnetic resonance imaging and echocardiography

2017 ◽  
Vol 312 (5) ◽  
pp. H932-H942 ◽  
Author(s):  
Jan Magnus Aronsen ◽  
Emil Knut Stenersen Espe ◽  
Kristine Skårdal ◽  
Almira Hasic ◽  
Lili Zhang ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Heart Failure ◽  
Magnetic Resonance ◽  
Clustering Algorithm ◽  
Left Ventricular ◽  
Resonance Imaging ◽  
Cardiovascular Research ◽  
Lung Weight ◽  
Magnetic Resonance Imaging Mri

The myocardial infarction (MI) rat model plays a crucial role in modern cardiovascular research, but the inherent heterogeneity of this model represents a challenge. We sought to identify subgroups among the post-MI rats and establish simple noninvasive stratification protocols for such subgroups. Six weeks after induction of MI, 49 rats underwent noninvasive examinations using magnetic resonance imaging (MRI) and echocardiography. Twelve sham-operated rats served as controls. Increased end-diastolic left ventricular (LV) pressure and lung weight served as indicators for congestive heart failure (CHF). A clustering algorithm using 13 noninvasive and invasive parameters was used to identify distinct groups among the animals. The cluster analysis revealed four distinct post-MI phenotypes; two without congestion but with different degree of LV dilatation, and two with different degree of congestion and right ventricular (RV) affection. Among the MRI parameters, RV mass emerged as robust noninvasive marker of CHF with 100% specificity/sensitivity. Moreover, LV infarct size and RV ejection fraction further predicted subgroup among the non-CHF and CHF rats with excellent specificity/sensitivity. Of the echocardiography parameters, left atrial diameter predicted CHF. Moreover, LV end-diastolic diameter predicted the subgroups among the non-CHF rats. We propose two simple noninvasive schemes to stratify post-MI rats, based on the degree of heart failure; one for MRI and one for echocardiography. NEW & NOTEWORTHY In vivo phenotyping of rats is essential for robust and reliable data. Here, we present two simple noninvasive schemes for the stratification of postinfarction rats based on the degree of heart failure: one using magnetic resonance imaging and one based on echocardiography.

scholarly journals Non-invasive diagnostics in fossils - Magnetic Resonance Imaging of pathological belemnites

2005 ◽  
Vol 2 (2) ◽  
pp. 133-140 ◽  
Author(s):  
D. Mietchen ◽  
H. Keupp ◽  
B. Manz ◽  
F. Volke
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Soft Tissue ◽  
Clinical Diagnostics ◽  
Resonance Imaging ◽  
Non Invasive ◽  
Physiological Processes ◽  
Magnetic Resonance Imaging Mri ◽  
Invasive Diagnostics

Abstract. For more than a decade, Magnetic Resonance Imaging (MRI) has been routinely employed in clinical diagnostics because it allows non-invasive studies of anatomical structures and physiological processes in vivo and to differentiate between healthy and pathological states, particularly of soft tissue. Here, we demonstrate that MRI can likewise be applied to fossilized biological samples and help in elucidating paleopathological and paleoecological questions: Five anomalous guards of Jurassic and Cretaceous belemnites are presented along with putative paleopathological diagnoses directly derived from 3D MR images with microscopic resolution. Syn vivo deformities of both the mineralized internal rostrum and the surrounding former soft tissue can be traced back in part to traumatic events of predator-prey-interactions, and partly to parasitism. Besides, evidence is presented that the frequently observed anomalous apical collar might be indicative of an inflammatory disease. These findings highlight the potential of Magnetic Resonance techniques for further paleontological applications.

scholarly journals Perspectives on the Role of Magnetic Resonance Imaging (MRI) for Noninvasive Evaluation of Diabetic Kidney Disease

2021 ◽  
Vol 10 (11) ◽  
pp. 2461
Author(s):  
José María Mora-Gutiérrez ◽  
María A. Fernández-Seara ◽  
Rebeca Echeverria-Chasco ◽  
Nuria Garcia-Fernandez
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Kidney Disease ◽  
Diabetic Kidney Disease ◽  
Imaging Biomarkers ◽  
Major Advance ◽  
Resonance Imaging ◽  
Diabetic Kidney ◽  
Magnetic Resonance Imaging Mri

Renal magnetic resonance imaging (MRI) techniques are currently in vogue, as they provide in vivo information on renal volume, function, metabolism, perfusion, oxygenation, and microstructural alterations, without the need for exogenous contrast media. New imaging biomarkers can be identified using these tools, which represent a major advance in the understanding and study of the different pathologies affecting the kidney. Diabetic kidney disease (DKD) is one of the most important diseases worldwide due to its high prevalence and impact on public health. However, its multifactorial etiology poses a challenge for both basic and clinical research. Therefore, the use of novel renal MRI techniques is an attractive step forward in the comprehension of DKD, both in its pathogenesis and in its detection and surveillance in the clinical practice. This review article outlines the most promising MRI techniques in the study of DKD, with the purpose of stimulating their clinical translation as possible tools for the diagnosis, follow-up, and monitoring of the clinical impacts of new DKD treatments.

Abstract MP31: Left Ventricular Hypertrophy by Electrocardiogram versus Cardiac Magnetic Resonance Imaging as a Predictor for Heart Failure: The MESA Study

Circulation ◽  
2016 ◽  
Vol 133 (suppl_1) ◽  
Author(s):  
Abdullahi O Oseni ◽  
Waqas T Qureshi ◽  
Mohammed F Almahmoud ◽  
Alain Bertoni ◽  
David A Bluemke ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Heart Failure ◽  
Cardiac Magnetic Resonance ◽  
Magnetic Resonance ◽  
Left Ventricular Hypertrophy ◽  
Cardiac Magnetic Resonance Imaging ◽  
Ventricular Hypertrophy ◽  
Predictive Ability ◽  
Left Ventricular ◽  
Resonance Imaging

Background: Left ventricular hypertrophy (LVH) is an established risk factor for heart failure (HF). However, it is unknown whether LVH detected by electrocardiogram (ECG-LVH) is equivalent to LVH ascertained by cardiac magnetic resonance imaging (MRI-LVH) in terms of prediction of incident HF using risk prediction models like the Framingham Heart Failure Risk Score (FHFRS). Methods: This analysis included 4745 (mean age 61+10 years, 53.5% women, 61.7% non-whites) from the Multi-Ethnic Study of Atherosclerosis who were free of cardiovascular disease at the time of enrollment. ECG-LVH was defined using Cornell’s criteria while MRI-LVH was derived from left ventricular (LV) mass measured by cardiac MRI. Cox proportional hazard regression was used to examine the association between ECG-LVH and MRI-LVH with incident HF. Harrell’s concordance C-index was used to estimate the predictive ability of the FHFRS when either ECG-LVH or MRI-LVH were included as one of its components. The added predictive ability of ECG-LVH and MRI-LVH were investigated using integrated discrimination improvement (IDI) index and relative IDI. Results: ECG-LVH was present in 291(6.1%) while MRI-LVH was present in 499 (10.5%) of the participants. Over a median follow up of 10.4 years, 140 participants developed HF. Both ECG-LVH [HR (95% CI): 2.25(1.38-3.69)] and MRI-LVH [HR (95% CI): 3.80(1.56-5.63)] were associated with an increased risk of HF in multivariable adjusted models (Table 1). The ability of FHFRS to predict HF was improved with MRI-LVH (C-index 0.871, 95% CI: 0.842-0.899) when compared with ECG-LVH (C-index 0.860, 95% CI: 0.833-0.888) (p < 0.0001). To assess the potential clinical utility of using LVH-MRI instead of ECG-LVH, we calculated several measures of reclassification (Table 1), which were consistent with the statistically significantly improved C-statistic with MRI-LVH. Conclusion: Both ECG-LVH and MRI-LVH are predictive of HF when used in the FHFRS. Substituting MRI-LVH for ECG-LVH improves the predictive ability of the FHFRS.

In Vivo MR Studies of Dynamic Changes in the Interosseous Membrane of the Forearm During Rotation

1999 ◽  
Vol 24 (2) ◽  
pp. 245-248 ◽  
Author(s):  
T. NAKAMURA ◽  
Y. YABE ◽  
Y. HORIUCHI
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Interosseous Membrane ◽  
Resonance Imaging ◽  
Forearm Rotation ◽  
Dynamic Changes ◽  
Magnetic Resonance Imaging Mri ◽  
Membranous Part ◽  
The Right

In vivo dynamic changes in the interosseous membrane (IOM) during forearm rotation were studied using magnetic resonance imaging (MRI). The right forearms of 20 healthy volunteers were examined in five different rotational positions. Axial slices were obtained at the proximal quarter, the middle and the distal quarter of the forearm. The changes in shape of the IOM during rotation were observed in an axial MR plane. For each image, we measured the interosseous distance and the length of the interosseous membrane. Images of the tendinous and membranous parts of the IOM could be differentiated by thickness. There were minimal dynamic changes in the tendinous part on the MRI while the membranous part showed numerous changes during rotation. The interosseous distance and the length of the interosseous membrane were maximum from a neutral to a slightly supinated position. The tendinous part is considered to be taut during rotation to provide stability between the radius and the ulna, but the membranous part which is soft, thin and elastic, allows smooth rotation.

Measurement of the Human Cochlear Spiral Curvature In Vivo

2013 ◽  
Vol 284-287 ◽  
pp. 1552-1558
Author(s):  
Jen Fang Yu ◽  
Kun Che Lee
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Inner Ear ◽  
Cochlear Implantation ◽  
Resonance Imaging ◽  
Basal Turn ◽  
Magnetic Resonance Imaging Mri ◽  
Human Inner Ear

This research aims to characterize the geometry of the human cochlear spiral in vivo by measuring curvature and length. Magnetic resonance imaging (MRI) was used to visualise the human inner ear in vivo. The inner ear was imaged in 12 ears in 7 subjects recruited. Visualisation of the cochlear spiral was enhanced by T2 weighting and further processing of the raw images. The spirals were divided into 3 segments: the basal turn segment, the middle turn segment and the apex turn segment. The length and curvature of each segment were measured. The measured lengths of cochlear spiral are consistent with data in the literature derived from anatomical dissections. Overall, the apex turn segment of the cochlear had the greatest degree of curvature. A detailed description of the cochlear spiral is provided, using measurements of curvature and length. This data will provide a valuable reference in the development of cochlear implantation procedures.

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