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Assessment of myofiber microstructure changes due to atrophy and recovery with time-dependent diffusion MRI

Lemberskiy, Gregory; Feiweier, Thorsten; Gyftopoulos, Soterios; Axel, Leon; Novikov, Dmitry S; Fieremans, Els
Current clinical MRI evaluation of musculature largely focuses on nonquantitative assessments (including T1-, T2- and PD-weighted images), which may vary greatly between imaging systems and readers. This work aims to determine the efficacy of a quantitative approach to study the microstructure of muscles at the cellular level with the random permeable barrier model (RPBM) applied to time-dependent diffusion tensor imaging (DTI) for varying diffusion time. Patients (N = 15, eight males and seven females) with atrophied calf muscles due to immobilization of one leg in a nonweight-bearing cast, were enrolled after providing informed consent. Their calf muscles were imaged with stimulated echo diffusion for DTI, T1-mapping and RPBM modeling. Specifically, After cast removal, both calf muscles (atrophied and contralateral control leg) were imaged with MRI for all patients, with follow-up scans to monitor recovery of the atrophied leg for six patients after 4 and 8 weeks. We compare RPBM-derived microstructural metrics: myofiber diameter, a, and sarcolemma permeability, κ, along with macroscopic anatomical parameters (muscle cross-sectional area, fiber orientation, <θ>, and T1 relaxation). ROC analysis was used to compare parameters between control and atrophied muscle, while the Friedman test was used to evaluate the atrophied muscle longitudinally. We found that the RPBM framework enables measurement of microstructural parameters from diffusion time-dependent DTI, of which the myofiber diameter is a stronger predictor of intramuscular morphological changes than either macroscopic (anatomical) measurements or empirical diffusion parameters. This work demonstrates the potential of RPBM to assess pathological changes in musculature that seem undetectable with standard diffusion and anatomical MRI.
PMID: 34002901
ISSN: 1099-1492
CID: 4876922

Multinuclear MRI to disentangle intracellular sodium concentration and extracellular volume fraction in breast cancer

Ianniello, Carlotta; Moy, Linda; Fogarty, Justin; Schnabel, Freya; Adams, Sylvia; Axelrod, Deborah; Axel, Leon; Brown, Ryan; Madelin, Guillaume
The purpose of this work was to develop a novel method to disentangle the intra- and extracellular components of the total sodium concentration (TSC) in breast cancer from a combination of proton ([Formula: see text]H) and sodium ([Formula: see text]) magnetic resonance imaging (MRI) measurements. To do so, TSC is expressed as function of the intracellular sodium concentration ([Formula: see text]), extracellular volume fraction (ECV) and the water fraction (WF) based on a three-compartment model of the tissue. TSC is measured from [Formula: see text] MRI, ECV is calculated from baseline and post-contrast [Formula: see text]H [Formula: see text] maps, while WF is measured with a [Formula: see text]H chemical shift technique. [Formula: see text] is then extrapolated from the model. Proof-of-concept was demonstrated in three healthy subjects and two patients with triple negative breast cancer. In both patients, TSC was two to threefold higher in the tumor than in normal tissue. This alteration mainly resulted from increased [Formula: see text] ([Formula: see text] 30 mM), which was [Formula: see text] 130% greater than in healthy conditions (10-15 mM) while the ECV was within the expected range of physiological values (0.2-0.25). Multinuclear MRI shows promise for disentangling [Formula: see text] and ECV by taking advantage of complementary [Formula: see text]H and [Formula: see text] measurements.
PMID: 33664340
ISSN: 2045-2322
CID: 4801862

Analysis of three-chamber view conventional and tagged cine MRI in patients with suspected hypertrophic cardiomyopathy

Chitiboi, Teodora; Kanski, Mikael; Tautz, Lennart; Hennemuth, Anja; Halpern, Dan; Sherrid, Mark; Axel, Leon
OBJECTIVES/OBJECTIVE:To investigate the potential value of adding a tagged three-chamber (3Ch) cine to clinical hypertrophic cardiomyopathy (HCM) magnetic resonance imaging (MRI) protocols, including to help distinguish HCM patients with regionally impaired cardiac function. METHODS:Forty-eight HCM patients, five patients with "septal knuckle" (SK), and 20 healthy volunteers underwent MRI at 1.5T; a tagged 3Ch cine was added to the protocol. Regional strain, myocardial wall thickness, and mitral valve leaflet lengths were measured in the 3Ch view. RESULTS:In HCM, we found a reduced tangential strain with decreased diastolic relaxation in both hypertrophied (p = 0.003) and remote segments (p = 0.035). Strain in the basal septum correlated with the length of the coaptation zone + residual leaflet (r = 0.48, p < 0.001). In the basal free wall, patients with SK had faster relaxation compared to HCM patients with septal hypertrophy. DISCUSSION/CONCLUSIONS:The 3Ch tagged MRI sequence provides useful information for the examination of suspected HCM patients, with minimal additional time cost. Local wall function is closely associated with morphological changes of the mitral apparatus measured in the same plane and may provide insights into mechanisms of obstruction. The additional strain information may be helpful when analyzing local myocardial wall motion patterns in the presence of SK.
PMID: 32152793
ISSN: 1352-8661
CID: 4348832

Constrictive Pericarditis Caused by IgG4-Related Disease Requiring Pericardiectomy After Partial Response to Corticosteroids [Case Report]

Yuriditsky, Eugene; Dwivedi, Aeshita; Narula, Navneet; Axel, Leon; Horowitz, James M; Vaynblat, Mikhail
Immunoglobulin G4-related disease is a systemic fibroinflammatory disease; pericardial involvement has occasionally been reported in publications. A 79-year-old man with biopsy-proven immunoglobulin G4-related disease with pleural involvement was admitted in acute heart failure, with imaging and hemodynamic studies consistent with constrictive pericarditis. He was treated with corticosteroids for 2 months with partial response manifest by decreases in pericardial thickening and immunoglobulin G4 levels. However, persistent constriction required pericardiectomy, leading to significant symptomatic improvement. (Level of Difficulty: Intermediate.).
PMID: 34317017
ISSN: 2666-0849
CID: 4949402

Soft-Label Guided Semi-Supervised Learning for Bi-Ventricle Segmentation in Cardiac Cine MRI

Chapter by: Chang, Qi; Yan, Zhennan; Lou, Yixuan; Axel, Leon; Metaxas, Dimitris N.
in: Proceedings - International Symposium on Biomedical Imaging by
[S.l.] : IEEE Computer, 2020
pp. 1752-1755
ISBN: 9781538693308
CID: 4508742

Fully automatic segmentation of short-axis cardiac MRI using modified deep layer aggregation

Chapter by: Li, Zhongyu; Lou, Yixuan; Yan, Zhennan; Alraref, Subhi; Min, James K.; Axel, Leon; Metaxas, Dimitris N.
in: Proceedings - International Symposium on Biomedical Imaging by
[S.l.] : IEEE Computer, 2019
pp. 793-797
ISBN: 9781538636411
CID: 4164822

The discrete Fourier transform for golden angle linogram sampling

Helou, Elias S.; Zibetti, Marcelo V. W.; Axel, Leon; Block, Kai Tobias; Regatte, Ravinder R.; Herman, Gabor T.
ISSN: 0266-5611
CID: 4228192

Analysis of Three-Chamber View Tagged Cine MRI in Patients with Suspected Hypertrophic Cardiomyopathy [Meeting Abstract]

Kanski, Mikael; Chitiboi, Teodora; Tautz, Lennart; Hennemuth, Anja; Halpern, Dan; Sherrid, Mark, V; Axel, Leon
ISSN: 0302-9743
CID: 4221252

FR-Net: Joint Reconstruction and Segmentation in Compressed Sensing Cardiac MRI [Meeting Abstract]

Huang, Qiaoying; Yang, Dong; Yi, Jingru; Axel, Leon; Metaxas, Dimitris
ISSN: 0302-9743
CID: 4221242

Stylus/tablet user input device for MRI heart wall segmentation: efficiency and ease of use

Taslakian, Bedros; Pires, Antonio; Halpern, Dan; Babb, James S; Axel, Leon
OBJECTIVES/OBJECTIVE:To determine whether use of a stylus user input device (UID) would be superior to a mouse for CMR segmentation. METHODS:Twenty-five consecutive clinical cardiac magnetic resonance (CMR) examinations were selected. Image analysis was independently performed by four observers. Manual tracing of left (LV) and right (RV) ventricular endocardial contours was performed twice in 10 randomly assigned sessions, each session using only one UID. Segmentation time and the ventricular function variables were recorded. The mean segmentation time and time reduction were calculated for each method. Intraclass correlation coefficients (ICC) and Bland-Altman plots of function variables were used to assess intra- and interobserver variability and agreement between methods. Observers completed a Likert-type questionnaire. RESULTS:The mean segmentation time (in seconds) was significantly less with the stylus compared to the mouse, averaging 206±108 versus 308±125 (p<0.001) and 225±140 versus 353±162 (p<0.001) for LV and RV segmentation, respectively. The intra- and interobserver agreement rates were excellent (ICC≥0.75) regardless of the UID. There was an excellent agreement between measurements derived from manual segmentation using different UIDs (ICC≥0.75), with few exceptions. Observers preferred the stylus. CONCLUSION/CONCLUSIONS:The study shows a significant reduction in segmentation time using the stylus, a subjective preference, and excellent agreement between the methods. KEY POINTS/CONCLUSIONS:• Using a stylus for MRI ventricular segmentation is faster compared to mouse • A stylus is easier to use and results in less fatigue • There is excellent agreement between stylus and mouse UIDs.
PMID: 29721687
ISSN: 1432-1084
CID: 3056582