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Background: Cardiac magnetic resonance (MR) has become an essential diagnostic imaging modality in cardiovascular disease. However, the insufficient image quality of traditional breath-hold (BH) T2-weighted (T2W) imaging may compromise its diagnostic accuracy., Purpose: To assess the efficacy of the BLADE technique to reduce motion artifacts and improve the image quality., Material and Methods: Free-breathing TSE-T2W imaging sequence with cartesian and BLADE k-space trajectory were acquired in 20 patients. Thirty patients underwent conventional BH turbo spin-echo (TSE) T2W imaging and free-breathing BLADE T2W (FB BLADE-T2W) imaging. Twenty-one patients who had a signal loss of myocardium in BH short-axis T2W turbo inversion recovery (TSE-T2W-TIR) were scanned using free-breathing BLADE T2W turbo inversion recovery (BLADE TSE-T2W-TIR). The overall image quality, blood nulling, and visualization of the heart were scored on a 5-point Likert scale. The signal loss of myocardium, incomplete fat suppression near the myocardium, and the streaking or ghosting artifacts were noted in T2W-TIR sequences additionally., Results: The overall imaging quality, blood nulling, and the visualization of heart structure of FB BLADE-T2W imaging sequence were significantly better than those of FB T2W imaging with Cartesian k-space trajectory and BH TSE-T2W imaging sequence ( P <0.01). The FB BLADE TSE-T2W-TIR reduces the myocardium signal dropout ( P <0.05), incomplete fat suppression near myocardium ( P <0.05), and the streaking and ghosting artifacts ( P <0.05) in comparison with the BH TSE-T2W-TIR., Conclusions: FB BLADE T2W imaging provides improved myocardial visibility, less motion sensitivity, and better image quality. It may be applied in patients who have poor breath-holding capability.

Anticancer drug doxorubicin hydrochloride (DOX)-loaded photothermal nanocomposite MnFe 2 O 4 @mSiO 2 with magnetic targeting and T 1 /T 2 -weighted dual-mode magnetic resonance imaging of MnFe 2 O 4 core and NIR/pH-coupling sensitive mesoporous silica shell nanocarriers was designed and synthesized successfully. The anticancer drug DOX can be absorbed into mesoporous layer of MnFe 2 O 4 @mSiO 2 nanocomposite, which shows obvious photothermal/chemo dual-modal synergistic therapies triggered by NIR/pH. Under 808 nm irradiation, MnFe 2 O 4 can transform light into thermo, which can not only ablate tumor cells directly but also promote chemotherapy drugs releasing from mesoporous layer to kill tumor cells. The lower pH can also promote DOX releasing from mesoporous layer to enhance tumor inhibitory effect. It is confirmed that biocompatible DOX-MnFe 2 O 4 @mSiO 2 nanocomposites can act as a potential multifunctional platform for effective magnetic targeting photothermal/chemo dual-modal synergistic therapies with enhanced anti-tumor efficacy and T 1 /T 2 -weighted dual-mode magnetic resonance imaging (MRI) applications in vivo., (Copyright © 2016 Elsevier Inc. All rights reserved.)

808 nm excited upconversion nanoparticles (UCNPs) have received extensive attention in the biomedical areas. However, one of the limitations of UCNPs is their lower luminescence efficiency. Aimed at this problem, a series of BaGdF5-based UCNPs were prepared by a layer-by-layer procedure. And UC luminescence properties are optimized by varying the doping concentration of rare earth ions, amount and types of shells. It is found that if the amount of core BaGdF5:20%Yb(3+)/2%Er(3+) was fixed at 0.5 mmol, the optimized conditions of three shell layers are 0.3 mmol of BaGdF5:10%Yb(3+), 0.5 mmol of BaNdF5 and 0.5 mmol of BaGdF5. Thus the UC luminescence intensity of the resultant nanoparticles BaGdF5:20%Yb(3+)/2%Er(3+)@BaGdF5:10%Yb(3+)@BaNdF5@BaGdF5 (Er@Yb@Nd@Gd) is enhanced more than four times compared with that of BaGdF5:20%Yb(3+)/2%Er(3+)@BaGdF5:10%Yb(3+)@BaNdF5 (Er@Yb@Nd). To further improve the biocompatibility and applications in the biological field, carboxymethyl chitosan (CMC), a type of biocompatible water-transfer agent, was used as a capping ligand to modify the surface of Er@Yb@Nd@Gd. An antitumor drug doxorubicin (DOX) was loaded to the CMC-modified Er@Yb@Nd@Gd nanocarriers by electrostatic interactions. The DOX can be selectively released in an acidic environment, which shows a pH-triggered drug release behavior. On the other hand, Er@Yb@Nd@Gd nanoparticles have excellent magnetic properties due to the presence of Gd components. T1-weighted magnetic resonance imaging (MRI) reveals the concentration-dependent brightening effect with longitudinal relaxivity (r1) as high as 43.77 s(-1) (mM)(-1), much higher than that of previous Gd(3+)-based counterparts. The results indicate that this multifunctional drug delivery system is expected to be a promising platform for simultaneous cancer therapy and bioimaging.

BackgroundIntramyocardial hemorrhage (IMH) within myocardial infarction (MI) is associated with major adverse cardiovascular events. Bright-blood T2*-based cardiovascular magnetic resonance (CMR) has emerged as the reference standard for non-invasive IMH detection. Despite this, the dark-blood T2*-based CMR is becoming interchangeably used with bright-blood T2*-weighted CMR in both clinical and preclinical settings for IMH detection. To date however, the relative merits of dark-blood T2*-weighted with respect to bright-blood T2*-weighted CMR for IMH characterization has not been studied. We investigated the diagnostic capacity of dark-blood T2*-weighted CMR against bright-blood T2*-weighted CMR for IMH characterization in clinical and preclinical settings.Materials and methodsHemorrhagic MI patients (n = 20) and canines (n = 11) were imaged in the acute and chronic phases at 1.5 and 3 T with dark- and bright-blood T2*-weighted CMR. Imaging characteristics (Relative signal-to-noise (SNR), Relative contrast-to-noise (CNR), IMH Extent) and diagnostic performance (sensitivity, specificity, accuracy, area-under-the-curve, and inter-observer variability) of dark-blood T2*-weighted CMR for IMH characterization were assessed relative to bright-blood T2*-weighted CMR.ResultsAt both clinical and preclinical settings, compared to bright-blood T2*-weighted CMR, dark-blood T2*-weighted images had significantly lower SNR, CNR and reduced IMH extent (all p

To evaluate the performance of a deep learning-based method to automatically quantify left ventricular (LV) function from MR images in different cardiomyopathy. This retrospective study included MRI data sets from 2013 to 2020. Data on left ventricular function from patients with hypertrophic cardiomyopathy (HCM), patients with dilated cardiomyopathy (DCM), and healthy participants were analyzed. MRI data from a total of 388 patients were measured manually and automatically.The performance of Convolutional Neural Networks (CNNs) was evaluated based on the manual notes of two experienced observers: (a) LV segmentation accuracy, and (b) LV functional parameter accuracy. Bland-Altman analysis, Receiver operating Characteristic (ROC) curve analysis and Pearson correlation analysis were used to evaluate the consistency between fully automatic and manual diagnosis of HCM and DCM. The deep-learning CNN performed best in HCM in evaluating LV function and worst in DCM. Compared with manual analysis, four parameters of LV function in the HCM group showed high correlation (r at least >0.901), and the correlation of DCM in all parameters was weaker than that of HCM, especially EF (r2 = 0.776) and SV (r2 = 0.645). ROC curve analysis indicated that at the optimal cut-off value, EF from automatic segmentation identified DCM and HCM patients with sensitivity of 92.31 and 78.05%, specificity of 82.96 and 54.07%, respectively. Among different heart diseases, the analysis of cardiac function based on deep-learning CNN may have different performances, with DCM performing the worst and HCM the best and thus, special attention should be paid to DCM patients when assessing LV function through artificial intelligence method. LV function parameter obtained by artificial intelligence method may play an important role in the future AI diagnosis of HCM and DCM. These data for the first time objectively evaluate the performance of a commercially available deep learning-based method in cardiac function evaluation of different cardiomyopathy and point out its advantages and disadvantages in different cardiomyopathy. This work did not attempt to design the algorithm itself, but rather applied an already existing method to a test dataset of clinical data and evaluated the results for a limited number of cardiomyopathy. [ABSTRACT FROM AUTHOR]

Background: T2* cardiovascular magnetic resonance (CMR) is commonly used in the diagnosis of intramyocardial hemorrhage (IMH). For quantifying IMH with T2* CMR, despite the lack of consensus studies, two different methods [subject-specific T2* (ssT2*) and absolute T2* thresholding (aT2* < 20 ms)] are interchangeably used. We examined whether these approaches yield equivalent information. Methods: ST elevation myocardial infarction (STEMI) patients (n = 70) were prospectively recruited for CMR at 4–7 days post revascularization and for 6-month follow up (n = 43). Canines studies were performed for validation purposes, where animals (n = 20) were subject to reperfused myocardial infarction (MI) and those surviving the MI (n = 16) underwent CMR at 7 days and 8 weeks and then euthanized. Both in patients and animals, T2* of IMH and volume of IMH were determined using ssT2* and aT2* < 20 ms. In animals, ex-vivo T2* CMR and mass spectrometry for iron concentration ([Fe]Hemo) were determined on excised myocardial sections. T2* values based on ssT2* and absolute T2* threshold approaches were independently regressed against [Fe]Hemo and compared. A range of T2* cut-offs were tested to determine the optimized conditions relative to ssT2*. Results: While both approaches showed many similarities, there were also differences. Compared to ssT2*, aT2* < 20 ms showed lower T2* and volume of IMH in patients and animals independent of MI age (all p < 0.005). While T2* determined from both methods were highly correlated against [Fe]Hemo (R2 = 0.9 for both), the slope of the regression curve for ssT2* was significantly larger as compared to aT2* < 20 ms (0.46 vs. 0.32, p < 0.01). Further, slightly larger absolute T2* cut-offs (patients: 23 ms; animals: 25 ms) showed similar IMH characteristics compared to ssT2*. Conclusion: Current quantification methods have excellent capacity to identify IMH, albeit the T2*of IMH and volume of IMH based on aT2* < 20 ms are smaller compared to ssT2*. Thus the method used to quantify IMH from T2* CMR may influence the diagnosis for IMH. [ABSTRACT FROM AUTHOR]

Anticancer drug doxorubicin hydrochloride (DOX)-loaded photothermal nanocomposite MnFe 2 O 4 @mSiO 2 with magnetic targeting and T 1 /T 2 -weighted dual-mode magnetic resonance imaging of MnFe 2 O 4 core and NIR/pH-coupling sensitive mesoporous silica shell nanocarriers was designed and synthesized successfully. The anticancer drug DOX can be absorbed into mesoporous layer of MnFe 2 O 4 @mSiO 2 nanocomposite, which shows obvious photothermal/chemo dual-modal synergistic therapies triggered by NIR/pH. Under 808 nm irradiation, MnFe 2 O 4 can transform light into thermo, which can not only ablate tumor cells directly but also promote chemotherapy drugs releasing from mesoporous layer to kill tumor cells. The lower pH can also promote DOX releasing from mesoporous layer to enhance tumor inhibitory effect. It is confirmed that biocompatible DOX-MnFe 2 O 4 @mSiO 2 nanocomposites can act as a potential multifunctional platform for effective magnetic targeting photothermal/chemo dual-modal synergistic therapies with enhanced anti-tumor efficacy and T 1 /T 2 -weighted dual-mode magnetic resonance imaging (MRI) applications in vivo. [ABSTRACT FROM AUTHOR]

Multifunctional hollow nanocapsules with magnetic and upconversion luminescence properties were synthesized. Hollow Fe 3 O 4 @SiO 2 was firstly prepared by using rodlike β-FeOOH as the template followed by silica coating, calcinations and reduction. Then Fe 3 O 4 @SiO 2 @α-NaYF 4 :Yb 3+ ,Er 3+ nanocapsules (FeSiUCNP) were synthesized by the hydrothermal transformation of the Y(Yb 3+ , Er 3+ )(OH)CO 3 (YOC) deposited onto the surface of nanocapsules through a urea-assisted homogeneous precipitation method. The hollow nanocapsules with porous structure provide space and entrance for the drug molecules. Due to the outside shell of α-NaYF 4 :Yb 3+ , Er 3+ , the nanomaterial shows upconverting red emission upon 980 nm NIR-light excitation. Moreover, the nanocomposites with hollow magnetite core exhibit a high relaxivity with r 2 value of 183 mM −1 s −1 , which reveal the potential as T 2 -weighted contrast agents for magnetic resonance imaging (MRI). The as-prepared nanocapsules can be performed as anti-cancer drug carriers for investigation of drug loading/release properties, which demonstrated a sustained drug release pattern and a comparable cytotoxicity with free doxorubicin (DOX). The multifunctional nanocapsules incorporated upconverting luminescence, T 2 -weighted MRI imaging and drug targeting delivery modalities have great potential for theranostic applications in cancer treatment. [ABSTRACT FROM AUTHOR]

A correction to the article "Quantification of myocardial hemorrhage using T2* cardiovascular magnetic resonance at 1.5 T with ex-vivo validation" in the February 2022 issue is presented.

Abstract: Objective: The objective of this study was to elucidate the imaging and pathological features of extraskeletal mesenchymal chondrosarcomas (EMCs). Methods: Imaging findings of eight EMC cases were retrospectively analyzed. Results: Soft tissue masses with different patterns of mineralization were found in five cases on computed tomographic scans. On magnetic resonance images, peripherally located EMCs demonstrated mixed signal intensity on T2-weighted images and heterogeneous enhancement with both calcified and noncalcified areas. Conclusion: EMCs exhibited several characteristic imaging features, which when used in combination with the mineralization pattern, enhancement of the calcified area, and signal intensity feature might have diagnostic value for this rare tumor. [Copyright &y& Elsevier]

Magnetic Fe2O3nanorods with low cell toxicity were successfully synthesized viaa wet-chemical method. In vivostudies with a rabbit model show that the nanorods exhibit excellent T2signal enhancement. This work demonstrates that magnetic nanorods may provide a new type of MR enhancement agent for use in biomedical applications. [ABSTRACT FROM AUTHOR]

Background: Reperfusion therapy for acute myocardial infarction (MI) is lifesaving. However, the benefit of reperfusion therapy can be paradoxically diminished by reperfusion injury, which can increase MI size.Objectives: Hemorrhage is known to occur in reperfused MIs, but whether hemorrhage plays a role in reperfusion-mediated MI expansion is not known.Methods: We studied cardiac troponin kinetics (cTn) of ST-segment elevation MI patients (n = 70) classified by cardiovascular magnetic resonance to be hemorrhagic (70%) or nonhemorrhagic following primary percutaneous coronary intervention. To isolate the effects of hemorrhage from ischemic burden, we performed controlled canine studies (n = 25), and serially followed both cTn and MI size with time-lapse imaging.Results: CTn was not different before reperfusion; however, an increase in cTn following primary percutaneous coronary intervention peaked earlier (12 hours vs 24 hours; P < 0.05) and was significantly higher in patients with hemorrhage (P < 0.01). In hemorrhagic animals, reperfusion led to rapid expansion of myocardial necrosis culminating in epicardial involvement, which was not present in nonhemorrhagic cases (P < 0.001). MI size and salvage were not different at 1 hour postreperfusion in animals with and without hemorrhage (P = 0.65). However, within 72 hours of reperfusion, a 4-fold greater loss in salvageable myocardium was evident in hemorrhagic MIs (P < 0.001). This paralleled observations in patients with larger MIs occurring in hemorrhagic cases (P < 0.01).Conclusions: Myocardial hemorrhage is a determinant of MI size. It drives MI expansion after reperfusion and compromises myocardial salvage. This introduces a clinical role of hemorrhage in acute care management, risk assessment, and future therapeutics. [ABSTRACT FROM AUTHOR]