6 research outputs found
Classification of moving coronary calcified plaques based on motion artifacts using convolutional neural networks:a robotic simulating study on influential factors
Abstract Background Motion artifacts affect the images of coronary calcified plaques. This study utilized convolutional neural networks (CNNs) to classify the motion-contaminated images of moving coronary calcified plaques and to determine the influential factors for the classification performance. Methods Two artificial coronary arteries containing four artificial plaques of different densities were placed on a robotic arm in an anthropomorphic thorax phantom. Each artery moved linearly at velocities ranging from 0 to 60 mm/s. CT examinations were performed with four state-of-the-art CT systems. All images were reconstructed with filtered back projection and at least three levels of iterative reconstruction. Each examination was performed at 100%, 80% and 40% radiation dose. Three deep CNN architectures were used for training the classification models. A five-fold cross-validation procedure was applied to validate the models. Results The accuracy of the CNN classification was 90.2 ± 3.1%, 90.6 ± 3.5%, and 90.1 ± 3.2% for the artificial plaques using Inception v3, ResNet101 and DenseNet201 CNN architectures, respectively. In the multivariate analysis, higher density and increasing velocity were significantly associated with higher classification accuracy (all P  0.05). Conclusions The CNN achieved a high accuracy of 90% when classifying the motion-contaminated images into the actual category, regardless of different vendors, velocities, radiation doses, and reconstruction algorithms, which indicates the potential value of using a CNN to correct calcium scores
The influence of high-density lipoprotein cholesterol on maximal lipid core burden indexing thin cap fibrous atheroma lesions as assessed by near infrared spectroscopy
Background: Previous studies suggest that higher plasma concentrations of several lipid molecules are associated with higher lipid core burden index (LCBI) NIRS imaging. The aim of this study was to investigate whether an association between plasma lipids depends on plaque morphology (thin cap fibrous atheroma [TCFA] vs. non-TFCA) as measured by near-infrared spectroscopy–intravascular ultrasound (NIRS-IVUS).
Methods: 64 patients retrospectively enrolled were diagnosed with stable coronary artery disease or acute coronary syndrome who underwent NIRS-IVUS imaging. Before percutaneous coronary intervention, blood samples were collected for measurement of serum levels of total cholesterol (TC), low-density lipoprotein cholesterol (HDL-C), high-density lipoprotein cholesterol (HDL-C) and triglycerides. Patients were divided into two groups based on maxLCBI4mm and IVUS imaging. Those with maxLCBI4mm ≥ 323 were included into TCFA group (n = 35) while others were assigned to the non-TCFA group (n = 29).
Results: Thin cap fibrous atheroma (TCFA) lesions were significantly longer than the non-TCFA lesions (25.66 ± 9.56 vs. 17.03 ± 9.22, p = 0.001). TCFA characterizes greater plaque burden (78.4 [70.9, 82.2] vs. 72.70 [64.77, 76,05]; p = 0.021) and plaque volume (176.1 [110.75, 247.5] vs. 68.1 [55.58, 143.35]; p = 0.000) as compared to non-TCFA. In TCFA suspected lesions, there was no correlation between maxLCBI4mm and LDL levels (r = 0.105, p = 0.549) nor TC levels (r = –0.035, p = 0.844) but a negative correlation was found between HDL-C and maxLCBI4mm (r = –0.453, p = 0.007).
Conclusions: The present study showed that there was no correlation between plasma LDL-C, TCH and TG level and the amount of lipids in coronary plaque assessed by NIRS in both TCFA and non-TCFA groups. Only HDL-C correlated with maxLCBI4mm in TCFA lesions
Prediction models for different plaque morphology in non-significantly stenosed regions of saphenous vein grafts assessed with optical coherence tomography
Introduction: Coronary artery bypass grafting (CABG) is a method of choice in treatment of diffuse coronary artery disease (CAD), although it has some limitations such as late saphenous vein graft (SVG) patency loss, which occurs in one fifth of all conduits at 5 years. Since atherosclerosis in SVG has diffuse characteristics, it appears that significantly and non-significantly stenosed lesions may have an equal impact on worse prognosis. Aim: To assess non-significant lesions of SVG by the use of optical coherence tomography (OCT) and investigate the clinical and laboratory findings with the potential impact on plaque composition. Material and methods: Twenty-nine patients with 43 non-significant lesions were enrolled in the study. All variables were assessed using uni- and multivariable logistic regression analysis with each plaque morphology as a dependent variable. Odds ratio (OR) and 95% confidence interval (CI) were computed. Results: Plaque rupture (PRT) was independently associated with age (OR = 1.49, 95% CI: 1.09–2.04, p = 0.015) and lower rates of high-density lipoproteins (HDL) cholesterol (OR = 0.67, 95% CI: 0.49–0.92, p = 0.016). Intimal tearing or rupture (ITR) was related to reduced GFR (OR = 0.52, 95% CI: 0.38–0.72, p = 0.0004). Lipid-rich plaque (LRP) was associated with raised platelet count (PLT) (OR = 1.51, 95% CI: 1.16–1.96, p = 0.004) and increased frequency of smoking (OR = 1.45, 95% CI: 1.12–1.89, p = 0.007). Conclusions: Atherosclerosis of SVG is not restricted to significantly stenosed lesions. Plaque composition is independently associated with different types of clinical and laboratory findings, mostly recognized as risk factors of CAD
Bone Mineral Density in Transgender Individuals After Gonadectomy and Long-Term Gender-Affirming Hormonal Treatment
Introduction: Establishing the influence of long-term, gender-affirming hormonal treatment (HT) on bone mineral density (BMD) in transgender individuals is important to improve the therapeutic guidelines for these individuals. Aim: To examine the effect of long-term HT and gonadectomy on BMD in transgender individuals. Methods: 68 transwomen and 43 transmen treated with HT who had undergone gonadectomy participated in this study. Dual-energy x-ray absorptiometry (DXA) scans were performed to measure BMD at the lumbar spine and total hip. Laboratory values related to sex hormones were collected within 3 months of performing the DXA scan and analyzed. Main Outcome Measure: BMD and levels of sex hormones in transwomen and transmen. Results: In transwomen, the mean BMD values at the lumbar spine and total hip at the first DXA scan were, respectively, 0.99 ± 0.15 g/cm2 (n = 68) and 0.94 ± 0.28 g/cm2 (n = 65). In transmen, the mean BMD values at the lumbar spine and total hip at the first DXA scan were, respectively, 1.08 ± 0.16 g/cm2 (n = 43) and 1.01 ± 0.18 g/cm2 (n = 43). A significant decrease in total hip BMD was found in both transwomen and transmen after 15 years of HT compared with 10 years of HT (P =.02). Conclusion: In both transwomen and transmen, a decrease was observed in total hip bone mineral density after 15 years of HT compared to the first 10 years of HT. Dobrolińska M, van der Tuuk K, Vink P, et al. Bone Mineral Density in Transgender Individuals After Gonadectomy and Long-Term Gender-Affirming Hormonal Treatment. J Sex Med 2019; 16:1469–1477