Unveiling the distinctive ossification patterns of diffuse idiopathic skeletal hyperostosis and ankylosing spondylitis using computed tomography three-dimensional reconstruction.

OBJECTIVE: To quantitatively analyze the morphological characteristics of osteophytes in DISH and syndesmophytes in AS, and summarize different ossification patterns to help identify the two diseases. Associated factors for new bone formation would be investigated. METHODS: Fifty patients with DISH and 50 age-, sex-, CT examination site- matched patients with AS were enrolled. Radiographic and clinical data were reviewed. Osteophytes (syndesmophytes) in front of each vertebral body and the corresponding intervertebral disc space were defined as vertebral osteophytes unit (VOU). The volume, angle and location (contralateral, ipsilateral, bilateral) of osteophytes in each VOU were measured and compared between DISH and AS groups. RESULTS: In each VOU, the volume and angle of osteophytes in DISH were significantly larger. The best osteophytes volume and angle cutoff value in predicting DISH was 0.59 cm3 and 40.15°. Contralateral, bilateral, ipsilateral osteophytes were recorded in 59.32%, 36.38%, 4.3% of assessed VOUs in patients with DISH and 64.78%, 29.31%, 5.91% in AS (p<0.001), respectively. As to ipsilateral osteophytes, the volume was inversely correlated with the center of the vertebral body to the center of the descending aorta (DISH: r = -0.45, p= 0.01; AS: r = -0.83, p<0.001). Advanced age, disease duration, smoking and overweight contribute to the progression of osteophytes and syndesmophytes. CONCLUSION: Morphological features of osteophytes are helpful to distinguish DISH with AS. Aortic pulsations inhibit or hinder new bone formation in both DISH and AS. Maintaining normal BMI could postpone osteophytes formation.

An Energy Matching Vessel Segmentation Framework in 3-D Medical Images.

Accurate vascular segmentation from High Resolution 3-Dimensional (HR3D) medical scans is crucial for clinicians to visualize complex vasculature and diagnose related vascular diseases. However, a reliable and scalable vessel segmentation framework for HR3D scans remains a challenge. In this work, we propose a High-resolution Energy-matching Segmentation (HrEmS) framework that utilizes deep learning to directly process the entire HR3D scan and segment the vasculature to the finest level. The HrEmS framework introduces two novel components. Firstly, it uses the real-order total variation operator to construct a new loss function that guides the segmentation network to obtain the correct topology structure by matching the energy of the predicted segment to the energy of the manual label. This is different from traditional loss functions such as dice loss, which matches the pixels between predicted segment and manual label. Secondly, a curvature-based weight-correction module is developed, which directs the network to focus on crucial and complex structural parts of the vasculature instead of the easy parts. The proposed HrEmS framework was tested on three in-house multi-center datasets and three public datasets, and demonstrated improved results in comparison with the state-of-the-art methods using both topology-relevant and volumetric-relevant metrics. Furthermore, a double-blind assessment by three experienced radiologists on the critical points of the clinical diagnostic processes provided additional evidence of the superiority of the HrEmS framework.

A background parenchymal enhancement quantification framework of breast magnetic resonance imaging.

Background: Background parenchymal enhancement (BPE) is defined as the enhanced proportion of normal fibroglandular tissue on enhanced magnetic resonance imaging. BPE shows promise as a quantitative imaging biomarker (QIB). However, the lack of consensus among radiologists in their semi-quantitative grading of BPE limits its clinical utility. Methods: The main objective of this study was to develop a BPE quantification model according to clinical expertise, with the BPE integral being used as a QIB to incorporate both the volume and intensity of the enhancement metrics. The model was applied to 2,786 cases to compare our quantitative results with radiologists' semi-quantitative BPE grading to evaluate the effectiveness of using the BPE integral as a QIB for analyzing BPE. Comparisons between multiple groups of nonnormally distributed BPE integrals were performed using the Kruskal-Wallis test. Results: Our study found a considerable degree of concordance between our BPE quantitative integral and radiologists' semi-quantitative assessments. Specifically, our research results revealed significant variability in BPE integral attained through the BPE quantification framework among all semi-quantitative BPE grading groups labeled by experienced radiologists, including mild-moderate (P<0.001), mild-marked (P<0.001), and moderate-marked (P<0.001). Furthermore, there was an apparent correlation between BPE integral and BPE grades, with marked BPE displaying the highest BPE integral, followed by moderate BPE, with mild BPE exhibiting the lowest BPE integral value. Conclusions: The study developed and implemented a BPE quantification framework, which incorporated both the volume and intensity of enhancement and which could serve as a QIB for BPE.

Organising pneumonia caused by hormone (tamoxifen) therapy after radiotherapy for breast cancer: a case report and review of the literature.

Background: Five-year treatment with tamoxifen (TAM) has been the traditional standard of care for breast cancer. Organising pneumonia (OP) is a rare but significant complication of radiation therapy for breast cancer. The effect of TAM leading to OP has not yet been clearly documented. Case Description: This report describes the case of a 38-year-old female who developed progressive aggravation of round-like patchy bilateral pulmonary infiltrated with a reverse halo sign but without any clinical symptoms 5 months after TAM therapy, following breast-conserving surgery and radiotherapy (RT) for breast carcinoma. A lung biopsy was performed and revealed a histological pattern of OP. TAM therapy was discontinued, and subsequent gradual radiological improvement was observed. As there was no proof for TAM had caused the incident, TAM was re-administrated. Eight months after reinstitution of TAM, the same patchy migratory bilateral pulmonary infiltrated with reverse halo sign was found on chest CT with the patient claiming no discomforts nor any clinical symptoms. The diagnosis of TAM-related OP was made based on the exclusion of other causes and recurrence with the re-administration of TAM. The multidisciplinary team (MDT) concluded that TAM should be withdrawn and a "wait-and-see" approach was taken after a comprehensive assessment, instead of altering the medication or performing prophylactic mastectomy. Conclusions: The withdrawal and rechallenge of TAM strongly suggest that it may play a role as a cofactor in the occurrence of OP after RT for breast cancer, and RT may also be a cofactor in the occurrence of OP. It is extremely important to be alerted to the possibility of OP after concurrent or sequential hormonal therapy and RT.

Translational large animal model of coronary microvascular embolism: characterization by serial cardiac magnetic resonance and histopathology.

This study aimed to construct a large animal model of coronary microvascular embolism, and investigate whether it could mimic the clinical imaging phenotypes of myocardial hypoperfusion in patients with ST-segment elevation myocardial infarction (STEMI). Nine minipigs underwent percutaneous coronary embolization with microspheres, followed by cardiac magnetic resonance (CMR) on week 1, 2 and 4 post operation. Microvascular obstruction (MVO) was defined as the isolated hypointense core within the enhanced area on late gadolinium enhancement images, which evolved during a 4-week follow-up. Fibrotic fraction of the segments was measured by Masson trichrome staining using a panoramic analysis software. Iron deposit and macrophage infiltration were quantified based on Perl's blue and anti-CD163 staining, respectively. Seven out of 9 (77.8%) minipigs survived and completed all of the imaging follow-ups. Four out of 7 (57.1%) minipigs were identified as transmural infarct with MVO. The systolic wall thickening (SWT) of MVO zone was similar to that of infarct zone (P = 0.762). Histopathology revealed transmural deposition of collagen, with microvessels obstructed by microspheres. The fibrotic fraction of infarct with MVO segments was similar to that of infarct without MVO segments (P = 0.954). The fraction of iron deposit in infarct with MVO segments was higher than that of infarct without MVO segments (P < 0.05), but the fraction of macrophage infiltration between these two segments did not show statistical difference (P = 0.723). Large animal model of coronary microvascular embolism could mimic most clinical imaging phenotypes of myocardial hypoperfusion in patients with STEMI, demonstrated by serial CMR and histopathology.

Effects of Nicorandil Administration on Infarct Size in Patients With ST-Segment-Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention: The CHANGE Trial.

Background Nicorandil was reported to improve microvascular dysfunction and reduce reperfusion injury when administered before primary percutaneous coronary intervention. In this multicenter, prospective, randomized, double-blind clinical trial (CHANGE [Effects of Nicorandil Administration on Infarct Size in Patients With ST-Segment-Elevation Myocardial Infarction Undergoing Primary Percutaneous Coronary Intervention]), we investigated the effects of nicorandil administration on infarct size in patients with ST-segment-elevation myocardial infarction treated with primary percutaneous coronary intervention. Methods and Results A total of 238 patients with ST-segment-elevation myocardial infarction were randomized to receive intravenous nicorandil (n=120) or placebo (n=118) before reperfusion. Patients in the nicorandil group received a 6-mg intravenous bolus of nicorandil followed by continuous infusion at a rate of 6 mg/h. Patients in the placebo group received the same dose of placebo. The predefined primary end point was infarct size on cardiac magnetic resonance (CMR) imaging performed at 5 to 7 days and 6 months after reperfusion. CMR imaging was performed in 201 patients (84%). Infarct size on CMR imaging at 5 to 7 days after reperfusion was significantly smaller in the nicorandil group compared with the placebo (control) group (26.5±17.1 g versus 32.4±19.3 g; P=0.022), and the effect remained significant on long-term CMR imaging at 6 months after reperfusion (19.5±14.4 g versus 25.7±15.4 g; P=0.008). The incidence of no-reflow/slow-flow phenomenon during primary percutaneous coronary intervention was much lower in the nicorandil group (9.2% [11/120] versus 26.3% [31/118]; P=0.001), and thus, complete ST-segment resolution was more frequently observed in the nicorandil group (90.8% [109/120] versus 78.0% [92/118]; P=0.006). Left ventricular ejection fraction on CMR imaging was significantly higher in the nicorandil group than in the placebo group at both 5 to 7 days (47.0±10.2% versus 43.3±10.0%; P=0.011) and 6 months (50.1±9.7% versus 46.4±8.5%; P=0.009) after reperfusion. Conclusions In the present trial, administration of nicorandil before primary percutaneous coronary intervention led to improved myocardial perfusion grade, increased left ventricular ejection fraction, and reduced myocardial infarct size in patients with ST-segment-elevation myocardial infarction. Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT03445728.

Development and validation of a deep learning model for breast lesion segmentation and characterization in multiparametric MRI.

Importance: The utilization of artificial intelligence for the differentiation of benign and malignant breast lesions in multiparametric MRI (mpMRI) assists radiologists to improve diagnostic performance. Objectives: To develop an automated deep learning model for breast lesion segmentation and characterization and to evaluate the characterization performance of AI models and radiologists. Materials and methods: For lesion segmentation, 2,823 patients were used for the training, validation, and testing of the VNet-based segmentation models, and the average Dice similarity coefficient (DSC) between the manual segmentation by radiologists and the mask generated by VNet was calculated. For lesion characterization, 3,303 female patients with 3,607 pathologically confirmed lesions (2,213 malignant and 1,394 benign lesions) were used for the three ResNet-based characterization models (two single-input and one multi-input models). Histopathology was used as the diagnostic criterion standard to assess the characterization performance of the AI models and the BI-RADS categorized by the radiologists, in terms of sensitivity, specificity, accuracy, and the area under the receiver operating characteristic curve (AUC). An additional 123 patients with 136 lesions (81 malignant and 55 benign lesions) from another institution were available for external testing. Results: Of the 5,811 patients included in the study, the mean age was 46.14 (range 11-89) years. In the segmentation task, a DSC of 0.860 was obtained between the VNet-generated mask and manual segmentation by radiologists. In the characterization task, the AUCs of the multi-input and the other two single-input models were 0.927, 0.821, and 0.795, respectively. Compared to the single-input DWI or DCE model, the multi-input DCE and DWI model obtained a significant increase in sensitivity, specificity, and accuracy (0.831 vs. 0.772/0.776, 0.874 vs. 0.630/0.709, 0.846 vs. 0.721/0.752). Furthermore, the specificity of the multi-input model was higher than that of the radiologists, whether using BI-RADS category 3 or 4 as a cutoff point (0.874 vs. 0.404/0.841), and the accuracy was intermediate between the two assessment methods (0.846 vs. 0.773/0.882). For the external testing, the performance of the three models remained robust with AUCs of 0.812, 0.831, and 0.885, respectively. Conclusions: Combining DCE with DWI was superior to applying a single sequence for breast lesion characterization. The deep learning computer-aided diagnosis (CADx) model we developed significantly improved specificity and achieved comparable accuracy to the radiologists with promise for clinical application to provide preliminary diagnoses.

A simplified scoring protocol to improve diagnostic accuracy with the breast imaging reporting and data system in breast magnetic resonance imaging.

Background: The breast imaging reporting and data system (BI-RADS) lexicon provides a standardized terminology for describing leision characteristics but does not provide defined rules for converting specific imaging features into diagnostic categories. The inter-reader agreement of the BI-RADS is moderate. In this study, we explored the use of a simplified protocol and scoring system for BI-RADS categorization which integrates the morphologic features (MF), kinetic time-intensity curve (TIC), and apparent diffusion coefficient (ADC) values with equal weights, with a view to providing a convenient and practical method for breast magnetic resonance imaging (MRI) and improving the inter-reader agreement and diagnostic performance of BI-RADS. Methods: This cross-sectional, retrospective, single-center study included 879 patients with 898 histopathologically verified lesions who underwent an MRI scan on a 3.0 Tesla GE Discovery 750 MRI scanner between January 1, 2017, and June 30, 2020. The BI-RADS categorization of the studied lesions was assessed according to the sum of the assigned scores (the presence of malignant MF, lower ADC, and suspicious TIC each warranted a score of +1). Total scores of +2 and +3 were classified as category 5, scores of +1 were classified as category 4, and scores of +0 but with other lesions of interest were classified as category 3. The receiver operating characteristic (ROC) curves were plotted, and the sensitivity, specificity, and accuracy of this categorization were investigated to assess its efficacy and its consistency with pathology. Results: There were 472 malignant, 104 risk, and 322 benign lesions. Our simplified scoring protocol had high diagnostic accuracy, with an area under curve (AUC) value of 0.896. In terms of the borderline effect of pathological risk and category 4 lesions, our results showed that when risk lesions were classified together with malignant ones, the AUC value improved (0.876 vs. 0.844 and 0.909 vs. 0.900). When category 4 and 5 lesions were classified as malignant, the specificity, accuracy, and AUC value decreased (82.3% vs. 93.2%, 89.3% vs. 90.2%, and 0.876 vs. 0.909, respectively). Therefore, to improve the diagnostic accuracy of the protocol for BI-RADS categorization, only category 5 lesions should be considered to be malignant. Conclusions: Our simplified scoring protocol that integrates MF, TIC, and ADC values with equal weights for BI-RADS categorization could improve both the diagnostic performance of the protocol for BI-RADS categorization in clinical practice and the understanding of the benign-risk-malignant breast diseases.

Impact of apical and mid-ventricular transmural infarcts in patients with acute myocardial infarction determined by using late gadolinium enhancement combined with feature tracking magnetic resonance.

Background: To analyze the relationship between left ventricular (LV) myocardial strain and transmurality of myocardial infarction at three circular sections (basal, mid-ventricular, apical) by a combined analysis of cardiac magnetic resonance feature tracking (CMR-FT) and late gadolinium enhancement (LGE) information in a cohort of ST-elevation acute myocardial infarction (STEMI) patients after primary percutaneous coronary intervention (PPCI). Methods: In all, 136 patients with STEMI who underwent PPCI within 12 hours of symptom onset were included. CMR-FT and LGE-MRI were performed 5±2 days after PCI for measuring regional and global myocardial strain indexes and transmural extent. Multivariate regression analysis and Kaplan-Meier survival analysis were performed. Results: Regional radial and circumferential strain decreased with increasing transmurality of myocardial infarction irrespective of basal, mid-ventricular, or apical segments. Segmental longitudinal strain was significantly decreased in the transmural infarcted segments only at the apical and mid-ventricular levels. A significant correlation was found between the number of transmural infarcts and global strain parameters in the apical and mid-ventricular portions. Transmural infarcted segments in apical + mid-ventricular portions >2 was related to an increased risk of cardiac events in patients with STEMI following PPCI than those ≤2. GLS was found to be an independent predictor of cardiac events in these patients. Conclusions: The number of transmural infarcted segments in apical + mid-ventricular portions affects LV global function and prognosis. Global longitudinal strain (GLS) is a significant predictor of adverse events after PPCI for STEMI. Morphologic and functional data fused to study complex pathophysiologic processes of LV early after STEMI may help in risk stratification of patients.

Assisting scalable diagnosis automatically via CT images in the combat against COVID-19.

The pandemic of Coronavirus Disease 2019 (COVID-19) is causing enormous loss of life globally. Prompt case identification is critical. The reference method is the real-time reverse transcription PCR (RT-PCR) assay, whose limitations may curb its prompt large-scale application. COVID-19 manifests with chest computed tomography (CT) abnormalities, some even before the onset of symptoms. We tested the hypothesis that the application of deep learning (DL) to 3D CT images could help identify COVID-19 infections. Using data from 920 COVID-19 and 1,073 non-COVID-19 pneumonia patients, we developed a modified DenseNet-264 model, COVIDNet, to classify CT images to either class. When tested on an independent set of 233 COVID-19 and 289 non-COVID-19 pneumonia patients, COVIDNet achieved an accuracy rate of 94.3% and an area under the curve of 0.98. As of March 23, 2020, the COVIDNet system had been used 11,966 times with a sensitivity of 91.12% and a specificity of 88.50% in six hospitals with PCR confirmation. Application of DL to CT images may improve both efficiency and capacity of case detection and long-term surveillance.

Independent and combined effects of hypertension and diabetes on clinical outcomes in patients with COVID-19: A retrospective cohort study of Huoshen Mountain Hospital and Guanggu Fangcang Shelter Hospital.

It is widely recognized that hypertension is one of the major risk factor for disease severity and mortality in patients with coronavirus disease 2019 (COVID-19). However, type 2 diabetes mellitus (T2DM) and hypertension are frequent comorbid conditions, complicating the assessment of hypertension's individual contribution to the risk. The aims of this study were to evaluate the contributions of hypertension alone, T2DM alone, or their combination to the risk of death, acute respiratory distress syndrome (ARDS)/respiratory failure, and severe COVID-19 infection. Additionally, we assessed risks associated with elevated blood pressure and fasting blood glucose on the same three clinical outcomes. Multivariate logistic models were used for these analyses. Among the 3400 patients, 3327(97.9%) survived and 73(2.1%) died. Compared to patients having neither hypertension nor T2DM (n = 1392), the risk of mortality was significantly higher in patients with T2DM alone (n = 226, OR 5.26 [95% CI: 2.39-11.58]) or with T2DM in combination with hypertension (n = 507, OR 3.02, [95% CI: 1.48-6.15]). Similarly, T2DM was a risk factor for development of ARDS/respiratory failure and severe infection. Hypertension alone (n = 1275) only conferred additional risk for the development of severe infection (OR 1.22 [95% CI: 1.00-1.51]). In conclusion, neither hypertension nor elevated blood pressure was independent risk factors for death or ARDS/respiratory failure but hypertension marginally increased the risk of severe COVID-19 infection. The risk associated with hypertension is accentuated through its confounding effect on T2DM.

The role of magnetic resonance imaging in detection and surgical treatment of breast intraductal papillomas.

BACKGROUND: Intraductal papillomas are discrete benign tumors of the breast duct epithelium. Due to the risk of subsequent carcinoma, a surgical excision is generally recommended as a precaution. However, it is difficult to initially diagnose and accurately locate the lesions both in pre-surgery and surgery periods. METHODS: Retrospectively analyzed 245 patients, with a pathologically proven breast intraductal papillomas. All the patients underwent magnetic resonance imaging (MRI) scans and ultrasound examination(s) pre-surgery and/or in surgery. All the patients who underwent surgery were divided into four groups according to the following operation method type(s): ultrasound & clinical examination excision, methylene blue notation excision, methylene blue notation & MRI guide excision, and MRI guide excision. Then, the differences between the last two MRI guide excisions and the first two conventional methods were analyzed. Afterwards, 238 patients were followed up for recurrence checks. SPSS 19.0 statistical software was used and the results of P<0.05 being considered statistically significant. RESULTS: A total of 161 (65.7%) and 48 (19.6%) patients were pathological diagnosed of solitary and multiple papilloma separately, and 36 (14.7%) patients had papillomatosis; 168 and 243 cases with positive signs, which were detected in all 245 patients who had underwent ultrasound and MRI examination(s), with the detection rate being 68.6% and 99.0% respectively. MRI imaging could clearly present mass-like lesions (solitary and multiple mass) and non-mass like lesions (ductal and regional). Whereas, ultrasound imaging could barely show mass-like (solitary and multiple mass) lesions. In surgery, when compared with traditional methods, MRI imaging could also more accurately locate the lesions and guide the excision. MRI guidance is both applicable to patients with and without nipple discharge, in addition to those who show no abnormal signs in ultrasound imaging. The recurrence-free survival time with traditional surgery methods was significantly lower than those in the MRI guide groups. CONCLUSIONS: MRI is accurate at the detection, localization and resection range of intraductal papilloma lesions; all capabilities which are critical to successful breast surgery.

Solitary fibrous tumor of the kidney: Magnetic resonance imaging characteristics in 4 patients.

To investigate the characteristics of magnetic resonance image (MRI) in solitary fibrous tumor (SFT) of the kidney.MRI findings and clinical features of SFT of the kidney in 4 patients (2 men and 2 women with a mean age of 37.8 ±â€Š8.7 years) were reviewed retrospectively. All patients were scanned by a 3.0-T magnetic resonance (MR) imaging system and the lesions were detected with emphasis on size, shape, location, margin, presence of pseudocapsule, signal intensity, degree of MR enhancement, and apparent diffusion coefficient (ADC).The 5 tumors from 4 patients were located in renal parenchyma (n = 1), renal pelvis (n = 3), and renal capsule (n = 1). On MRIs, the tumors were round (n = 1) or oval-shaped (n = 4), and presented pseudocapsule (n = 2) and well-circumscribed margins (n = 3) can be found. On T2-weighted images (T2WIs), solid components of the tumor presented homogeneously mild hypointensity or isointensity (n = 4) compared with the renal cortex. On diffusion-weighted images (DWIs), the lesions showed normal or mild hyperintensity (n = 4) with mean ADC of 1.687 × 10 mm/s. On dynamic contrast-enhanced MRIs, all lesions showed progressively mild enhancement. In the follow-up of 24 to 36 months after the surgery, 3 patients survived and 1 deceased.The SFT of the kidney appeared as a circle or oval and presented homogeneously mild hypointensity or isointensity on T2WIs, hyperintensity on DWIs, and progressively mild enhancement on DCE MRIs.

Rosai-Dorfman disease with features of IgG4-related disease in the breast: Cases report and literature review.

BACKGROUND: A proportion of cases of Rosai-Dorfman disease exhibit some histological features consistent with IgG4-related disease (IgG4RD). Several investigators have discussed whether Rosai-Dorfman disease belongs to the spectrum of IgG4RD or is concurrent with it by coincidence. OBJECTIVE: To elucidate the relationship between the two diseases, we report key features, including IgG4 and amyloid levels, of four cases of Rosai-Dorfman disease in the breast. METHODS: The histological features of the four cases were analyzed and the numbers of IgG4+ plasma cells and IgG4/IgG ratios were evaluated. Serum IgG4 concentrations were also measured in two recent cases. A literature review was also performed. RESULTS: Two cases (case 1 and 2) showed features of IgG4RD, including lymphoid follicle formation with regressive changes, obliterative phlebitis, increased number of IgG4+ plasma cells, and increased IgG4/IgG ratio; one of the two had an elevated serum IgG4 level. Amyloidosis was detected in these cases, with amyloid in the stroma and the vessel walls of the lesion. The other two cases (case 3 and 4) only had mild increases in the numbers of IgG4+ plasma cells, while amyloid was deposited in the stroma only. CONCLUSIONS: A subset of Rosai-Dorfman disease may overlap with IgG4RD in the breast. When Rosai-Dorfman disease has features of IgG4RD, amyloidosis could be induced in the lesion.

The Improvement of Torsion Assessed by Cardiovascular Magnetic Resonance Feature Tracking after Coronary Artery Bypass Grafting: A Sensitive Index of Cardiac Function.

OBJECTIVE: The aim of this study was to quantify left ventricular torsion by newly applied cardiovascular magnetic resonance feature tracking (CMR-FT), and to evaluate the clinical value of the ventricular torsion as a sensitive indicator of cardiac function by comparison of preoperative and postoperative torsion. METHODS: A total of 54 volunteers and 36 patients with previous myocardial infarction (MI) and LV ejection fraction (EF) between 30%-50% were screened preoperatively or postoperatively by MRI. The patients' short axis views of the whole heart were acquired, and all patients had a scar area >75% in at least one of the anterior or inferior segments. Their apical and basal rotation values were analyzed by feature tracking, and the correlation analysis was performed for the improvement of LV torsion and ejection fraction after CABG. The intra- and inter-observer reliabilities of torsion measured by CMR-FT were assessed. RESULTS: In normal hearts, the apex rotated counterclockwise in the systolic period with the peak rotation as 10.2 ± 4.8°, and the base rotated clockwise as the peak value was 7.0 ± 3.3°. There was a timing hiatus between the apex and base untwisting, during which period the heart recoils and its suction sets the stage for the following rapid filling period. The postoperative torsion and rotation significantly improved compared with preoperative ones. However, the traditional indicator of cardiac function, ejection fraction, didn't show significant improvement. CONCLUSION: Left ventricular torsion derived from CMR-FT, which does not require specialized CMR sequences, was sensitive to patients with low ejection fraction whose cardiac function significantly improved after CABG. The rapid acquisition of this measurement has potential for the assessment of cardiac function in clinical practice.

Feasibility of Automated Three-Dimensional Rotational Mechanics by Real-Time Volume Transthoracic Echocardiography: Preliminary Accuracy and Reproducibility Data Compared with Cardiovascular Magnetic Resonance.

BACKGROUND: Three-dimensional (3D) speckle-tracking echocardiography (STE) for myocardial strain imaging may be superior to two-dimensional STE, especially with respect to rotational mechanics. Automated strain measurements from nonstitched 3D STE may improve work flow and clinical utility. The aim of this study was to test the feasibility of model-based 3D STE for the automated measurement of voxel circumferential strain (Ecc) and myocardial rotation. METHODS: Thirty-five individuals (12 healthy volunteers, 12 patients with dilated cardiomyopathy, and 11 patients with hypertensive left ventricular [LV] hypertrophy) were prospectively studied. The latter two groups did not have significant coronary artery disease on coronary arteriography. Tagged cardiovascular magnetic resonance (CMR) and feature-tracking CMR were used as reference standards. Regional (apex and mid left ventricle) and slice (within a region) Ecc and rotation were measured by real-time volume transthoracic echocardiography (nonstitched) using an automated algorithm. RESULTS: Compared with both CMR techniques, apical and mid-LV Ecc (concordance correlation coefficients [CCCs], 0.84-0.95 and 0.48-0.68) and rotation (CCCs, 0.70-0.95 and 0.42-0.68) showed excellent, good, and moderate agreement, respectively. At the LV base, rotation showed poor agreement with CMR methods (CCC, 0.04-0.21), consistent with previous descriptions, but calculated LV twist showed moderate to good correlation with CMR techniques (CCC, 0.61-0.84). However, the 95% CI for measurements between techniques was wide, emphasizing the challenges in comparing voxel deformation by 3D echocardiography with CMR, compounded by differences in approaches to measuring deformation, and matching regional and slice measurements between techniques. Reproducibility (n = 10, including test-retest variability) of automated 3D strain and rotation measurements was good to excellent (coefficient of variation < 10%) and was comparable with that of CMR methods (coefficient of variation < 10%) in the same patients. CONCLUSIONS: The data from this study show that automated measurements of voxel rotational mechanics by real-time volume transthoracic echocardiography is feasible and comparable with tagged CMR and feature-tracking CMR strain measurements, albeit with wide limits of agreement, emphasizing the differences between the modalities. Furthermore, this automated 3D speckle-tracking echocardiographic approach shows excellent reproducibility, including test-retest variability, comparable with that of the CMR methods.

Three-dimensional fuse deposition modeling of tissue-simulating phantom for biomedical optical imaging.

Biomedical optical devices are widely used for clinical detection of various tissue anomalies. However, optical measurements have limited accuracy and traceability, partially owing to the lack of effective calibration methods that simulate the actual tissue conditions. To facilitate standardized calibration and performance evaluation of medical optical devices, we develop a three-dimensional fuse deposition modeling (FDM) technique for freeform fabrication of tissue-simulating phantoms. The FDM system uses transparent gel wax as the base material, titanium dioxide (TiO2 ) powder as the scattering ingredient, and graphite powder as the absorption ingredient. The ingredients are preheated, mixed, and deposited at the designated ratios layer-by-layer to simulate tissue structural and optical heterogeneities. By printing the sections of human brain model based on magnetic resonance images, we demonstrate the capability for simulating tissue structural heterogeneities. By measuring optical properties of multilayered phantoms and comparing with numerical simulation, we demonstrate the feasibility for simulating tissue optical properties. By creating a rat head phantom with embedded vasculature, we demonstrate the potential for mimicking physiologic processes of a living system.

Application of single shot free-breathing fast imaging employing steady state sequence in cardiac magnetic resonance imaging.

OBJECTIVE: To investigate the imaging quality of single shot (SS) fast imaging employing steady state (FIESTA) sequence in contrast-enhanced cardiac magnetic resonance (MR) examination, in comparison with the segmented inversion recovery 2D fast gradient echo (IR FGRE) sequence. MATERIALS AND METHODS: Fifty-two cases with suspected or known heart disease were enrolled in this study, including 24 patients who had enhanced myocardium in myocardial delayed enhancement (MDE). We analyzed the imaging quality of the sequences by measuring the myocardium and blood pool signal-to-noise ratios (SNR) and the contrast-to-noise ratios (CNR) of blood pool relative to normal myocardium and of enhanced myocardium relative to normal myocardium and compared the new sequences with traditional sequence. RESULTS: The scanning time of SS FIESTA was significantly shortened as compared to IR FGRE. The differences in the image quality scores, enhanced myocardium (EM) mass and percentages, SNR(bp), SNR(myo), CNR(myo/bp) and CNR(l/bg) were not statistically significant between SS FIESTA and IR FGRE (P > 0.05). However, the difference in CNR(em/myo) was statistically significant between SS FIESTA and IR FGRE (P < 0.0001), with CNR(em/myo) of IR FGRE higher than SS FIESTA. CONCLUSION: Single shot FIESTA speeded up the acquisition time, halving it to (27.6 ± 1.8 s) instead of 146 + 13.8 s (IR FGRE), it had higher SNR and CNR, and its image quality did not differ significantly from IR FGRE. The SS FIESTA is more suitable for patients with severely heart diseases or those unable to hold breath. 3D IR FGRE sequence had higher SNR(myo) than the others and it is suitable for displaying the subendocardial scar. However, it has more artefacts and poor imaging quality than IR FGRE.

[Value of assessing left ventricular longitudinal systolic peak strain in differential diagnosis of primary cardiac amyloidosis from hypertrophic cardiomyopathy].

OBJECTIVE: To analyze the endocardial, myocardial, and epicardial longitudinal systolic strain (LSsys) in the left ventricle (LV) segments and walls in patients with cardiac involvement due to primary amyloidosis (AL-CA) and hypertrophic cardiomyopathy (HCM). METHODS: Twenty patients with biopsy-proven AL-CA, 20 with asymmetric HCM, and 20 age-matched healthy volunteers were analyzed for their clinical characteristics and underwent conventional echocardiography for evaluating LV wall thickness, left atrial and ventricle size, systolic and diastolic function and 2-dimensional velocity vector imaging for evaluating the endocardial, myocardial and epicardial LSsys of the LV segments and walls. AL-CA and HCM patients also underwent cardiac magnetic resonance to evaluate the late gadolinium enhancement (LGE) features. RESULTS: Compared with the control group, AL-CA and HCM groups, with similar clinical symptoms and physical signs, both showed increased LV wall thickness, left atrial diameter, E/A ratio, septal E/e' ratio and the prevalence of granular sparkling. LV segments and walls endocardial LSsys were significantly lower in AL-CA patients than in HCM patients and the control subjects. The endocardial-epicardial LSsys difference in all the left ventricle walls were significantly smaller in AL-CA group than in the control group, but this difference appeared variable in HCM group. The LGE also presented with different features in AL-CA and HCM: AL-CA group showed subendocardial LGE in almost all the LV walls, but HCM group showed patchy LGE with a regional, multifocal distribution. CONCLUSION: AL-CA is characterized by a significantly reduced endocardial LSsys in the LV segments and an uniform decrease of the endocardial-epicardial LSsys difference in all the LV walls, but the changes in HCM appear variable, and 2-dimensional velocity vector imaging is therefore a useful modality to differentiate AL-CA from HCM.

[Analysis of clinical and imaging features of cardiac amyloidosis: a multicenter study].

OBJECTIVE: To summarize the features of clinical manifestations, laboratory tests and imaging findings of patients with cardiac amyloidosis (CA). METHODS: A total of 60 CA patients (including 41 male and 19 female patients) from 4 centers admitted between May, 2012 and November, 2013 were included in the study. The demographic data, medical history, clinical manifestations, laboratory test data, ECG, cardiac ultrasound, and cardiac magnetic resonance (CMR) imaging of the patients were analyzed. RESULTS: Two-thirds of the 60 CA patients, were middle-aged or elderly men, and 47% of the patients had AL-CA. The clinical manifestations included exertional dyspnea (73%), pedal edema (47%), hypotension (47%), and hypertrophy of the tongue (22%); abnormal laboratory test results included albuminuria (53%) and liver (15%) and kidney (28%) dysfunction; blood routine, urine and serum immunoglobulin quantification and immunofixation electrophoresis could help the screening of AL-CA. Kidney (53%) and liver (15%) involvement was common, and 86% of AL-CA patients had kidney involvement. Typical ECG characteristics included poor R wave progression (35%), low voltage in limb leads (33%), and a pseudo infarct Q wave (30%); the latter two were more frequent in AL-CA. The characteristics of ultrasound findings included left ventricle thickening (100%), left atrial enlargement (87%) and enhanced echo of the myocardial granules(92%), and diastolic dysfunction was obvious in all the CA patients regardless of the systolic function. The DT and E/e' of the mitral annulus could be used as an index to evaluate diastolic dysfunction in early stage of the disease. Left ventricular (LV) global subendocardial late gadolinium enhancement (LGE, 81%) accompanied by right ventricular (RV) and atrial LGE was the typical characteristic of CMR, and the range of LGE in the RV and the two atria was wider in AL-CA than in non-AL-CA. NT-proBNP (97%) and cardiac troponin (53%) in CA patients were both elevated, which helped in diagnosing and assessing the severity of cardiac involvement, according to which 50% of the patients were found to be at a high risk, 43% at an intermediate risk, and 7% at a low risk. CONCLUSION: The combination of the features of clinical, laboratory tests and imaging findings of CA have important diagnostic and prognostic value for CA.