scholarly journals Fully Automatic Retinal Vascular Tortuosity Assessment Integrating Domain-Related Information

Proceedings ◽  
2020 ◽  
Vol 54 (1) ◽  
pp. 32
Author(s):  
Lucía Ramos ◽  
Jorge Novo ◽  
José Rouco ◽  
Stéphanie Romeo ◽  
María D. Álvarez ◽  
...  
Keyword(s):  
Circulatory System ◽  
Fundus Image ◽  
Non Invasive ◽  
Vascular Tortuosity ◽  
Related Information ◽  
Fully Automatic ◽  
Anatomical Properties ◽  
Retinal Vascular Tortuosity ◽  
Arteries And Veins

The fundus of the eye is the only part of the human body that allows a direct non-invasive observation of the circulatory system. Retinal vascular tortuosity presents a valuable potential for diagnostic and treatment purposes of relevant vascular and systemic diseases. This work presents a computational metric for the tortuosity characterization that combines mathematical representations of the vessel segments with anatomical properties of the fundus image such as the vessel caliber, the distance to the optic disc, the distance to the fovea and the distinction between arteries and veins. The evaluation of the prognostic performance shows that the incorporation of the domain-related information allows a reliable characterization of the retinal vascular tortuosity that provides a better representation of the expert perception.

scholarly journals Computational assessment of the retinal vascular tortuosity integrating domain-related information

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
L. Ramos ◽  
J. Novo ◽  
J. Rouco ◽  
S. Romeo ◽  
M. D. Álvarez ◽  
...  
Keyword(s):  
Fundus Image ◽  
Prognostic Performance ◽  
Mathematical Representations ◽  
Vascular Tortuosity ◽  
Related Information ◽  
Additional Domain ◽  
Clinical Biomarker ◽  
Anatomical Properties ◽  
Retinal Vascular Tortuosity ◽  
Arteries And Veins

AbstractThe retinal vascular tortuosity presents a valuable potential as a clinical biomarker of many relevant vascular and systemic diseases. Commonly, the existent approaches face the tortuosity quantification by means of fully mathematical representations of the vessel segments. However, the specialists, based on their diagnostic experience, commonly analyze additional domain-related information that is not represented in these mathematical metrics of reference. In this work, we propose a novel computational tortuosity metric that outperforms the mathematical metrics of reference also incorporating anatomical properties of the fundus image such as the distinction between arteries and veins, the distance to the optic disc, the distance to the fovea, and the vessel caliber. The evaluation of its prognostic performance shows that the integration of the anatomical factors provides an accurate tortuosity assessment that is more adjusted to the specialists’ perception.

Study of functional state of microcirculatory channel system in periodontal tissues in persons of different age groups

2020 ◽  
Vol 20 (2) ◽  
pp. 88-94
Author(s):  
L. Yu. Orekhova ◽  
A. A. Petrov ◽  
E. S. Loboda ◽  
I. V. Berezkina ◽  
K. V. Shadrina
Keyword(s):  
Functional State ◽  
Age Groups ◽  
Peripheral Resistance ◽  
Circulatory System ◽  
Structural Features ◽  
Periodontal Tissues ◽  
Non Invasive ◽  
Age Related ◽  
Group 12 ◽  
Therapeutic Measures

Relevance. The study of age-related features of microcirculation in periodontal tissues, using non-invasive functional research methods, allows us to develop the optimal range of therapeutic measures, as well as form a “personalized therapeutic case”.Purpose. Study of the functional state of the microvasculature in the tissues of the parodont in individuals of various age groups.Materials and methods. A standard dental examination of 80 patients was carried out, the sample of participants was ranked in 4 groups by age: 1 group – 12 years old, 2 group – 15 years old, 3 group – from 16 to 18 years old, 4 group – from 22 to 24 years old. Hygiene and periodontal indices were determined for all patients, such as papillarymarginal-alveolar (PMA) in the Parma modification, the Mulleman bleeding index in the Cowell modification (SBI), and the simplified Green Vermillion index of oral hygiene (OHI–s), caries intensity indicators for a permanent bite (CPI), as well as ultrasound dopplerography of periodontal tissues using the apparatus "Minimax-Doppler-K".Results. When studying microcirculation in periodontal tissues, distinctive characteristics of linear (Vas) and volumetric (Qas) blood flow rates, as well as indicators of pulsation indices (PI) and peripheral resistance (RI) in people of different age groups were recorded.Conclusions. This study confirms the presence of various hemodynamic indicators of periodontal tissues in the studied groups, which is due to structural features of the circulatory system in age periods.

scholarly journals A global non-invasive methodology for the phenotyping of potato under water deficit conditions using imaging, physiological and molecular tools

Plant Methods ◽  
2021 ◽  
Vol 17 (1) ◽  
Author(s):  
M. Musse ◽  
G. Hajjar ◽  
N. Ali ◽  
B. Billiot ◽  
G. Joly ◽  
...  
Keyword(s):  
Water Stress ◽  
Water Deficit ◽  
Soil Conditions ◽  
Growth Stages ◽  
Dry Matter Content ◽  
Tuber Growth ◽  
Non Invasive ◽  
Potato Plants ◽  
Significant Difference

Abstract Background Drought is a major consequence of global heating that has negative impacts on agriculture. Potato is a drought-sensitive crop; tuber growth and dry matter content may both be impacted. Moreover, water deficit can induce physiological disorders such as glassy tubers and internal rust spots. The response of potato plants to drought is complex and can be affected by cultivar type, climatic and soil conditions, and the point at which water stress occurs during growth. The characterization of adaptive responses in plants presents a major phenotyping challenge. There is therefore a demand for the development of non-invasive analytical techniques to improve phenotyping. Results This project aimed to take advantage of innovative approaches in MRI, phenotyping and molecular biology to evaluate the effects of water stress on potato plants during growth. Plants were cultivated in pots under different water conditions. A control group of plants were cultivated under optimal water uptake conditions. Other groups were cultivated under mild and severe water deficiency conditions (40 and 20% of field capacity, respectively) applied at different tuber growth phases (initiation, filling). Water stress was evaluated by monitoring soil water potential. Two fully-equipped imaging cabinets were set up to characterize plant morphology using high definition color cameras (top and side views) and to measure plant stress using RGB cameras. The response of potato plants to water stress depended on the intensity and duration of the stress. Three-dimensional morphological images of the underground organs of potato plants in pots were recorded using a 1.5 T MRI scanner. A significant difference in growth kinetics was observed at the early growth stages between the control and stressed plants. Quantitative PCR analysis was carried out at molecular level on the expression patterns of selected drought-responsive genes. Variations in stress levels were seen to modulate ABA and drought-responsive ABA-dependent and ABA-independent genes. Conclusions This methodology, when applied to the phenotyping of potato under water deficit conditions, provides a quantitative analysis of leaves and tubers properties at microstructural and molecular levels. The approaches thus developed could therefore be effective in the multi-scale characterization of plant response to water stress, from organ development to gene expression.

scholarly journals Current Trends in Non-Invasive Imaging of Interactions in the Liver Tumor Microenvironment Mediated by Tumor Metabolism

Cancers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 3645
Author(s):  
Isabel Theresa Schobert ◽  
Lynn Jeanette Savic
Keyword(s):  
Tumor Microenvironment ◽  
Liver Cancer ◽  
Cancer Cells ◽  
Imaging Techniques ◽  
Treatment Strategies ◽  
Tumor Metabolism ◽  
Resistance Mechanisms ◽  
Metabolic Reprogramming ◽  
Non Invasive

With the increasing understanding of resistance mechanisms mediated by the metabolic reprogramming in cancer cells, there is a growing clinical interest in imaging technologies that allow for the non-invasive characterization of tumor metabolism and the interactions of cancer cells with the tumor microenvironment (TME) mediated through tumor metabolism. Specifically, tumor glycolysis and subsequent tissue acidosis in the realms of the Warburg effect may promote an immunosuppressive TME, causing a substantial barrier to the clinical efficacy of numerous immuno-oncologic treatments. Thus, imaging the varying individual compositions of the TME may provide a more accurate characterization of the individual tumor. This approach can help to identify the most suitable therapy for each individual patient and design new targeted treatment strategies that disable resistance mechanisms in liver cancer. This review article focuses on non-invasive positron-emission tomography (PET)- and MR-based imaging techniques that aim to visualize the crosstalk between tumor cells and their microenvironment in liver cancer mediated by tumor metabolism.

scholarly journals Spectral Decomposition of the Flow and Characterization of the Sound Signals through Stenoses with Different Levels of Severity

2021 ◽  
Vol 8 (3) ◽  
pp. 41
Author(s):  
Fardin Khalili ◽  
Peshala T. Gamage ◽  
Amirtahà Taebi ◽  
Mark E. Johnson ◽  
Randal B. Roberts ◽  
...  
Keyword(s):  
Pressure Fluctuations ◽  
High Energy ◽  
Sound Sources ◽  
Severity Level ◽  
Non Invasive ◽  
Flow Through ◽  
Severity Of The Disease ◽  
Proper Orthogonal ◽  
Different Levels

Treatments of atherosclerosis depend on the severity of the disease at the diagnosis time. Non-invasive diagnosis techniques, capable of detecting stenosis at early stages, are essential to reduce associated costs and mortality rates. We used computational fluid dynamics and acoustics analysis to extensively investigate the sound sources arising from high-turbulent fluctuating flow through stenosis. The frequency spectral analysis and proper orthogonal decomposition unveiled the frequency contents of the fluctuations for different severities and decomposed the flow into several frequency bandwidths. Results showed that high-intensity turbulent pressure fluctuations appeared inside the stenosis for severities above 70%, concentrated at plaque surface, and immediately in the post-stenotic region. Analysis of these fluctuations with the progression of the stenosis indicated that (a) there was a distinct break frequency for each severity level, ranging from 40 to 230 Hz, (b) acoustic spatial-frequency maps demonstrated the variation of the frequency content with respect to the distance from the stenosis, and (c) high-energy, high-frequency fluctuations existed inside the stenosis only for severe cases. This information can be essential for predicting the severity level of progressive stenosis, comprehending the nature of the sound sources, and determining the location of the stenosis with respect to the point of measurements.

scholarly journals Cardiac Computed Tomography Radiomics for the Non-Invasive Assessment of Coronary Inflammation

Cells ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 879
Author(s):  
Kevin Cheng ◽  
Andrew Lin ◽  
Jeremy Yuvaraj ◽  
Stephen J. Nicholls ◽  
Dennis T.L. Wong
Keyword(s):  
Cardiac Computed Tomography ◽  
Quantitative Information ◽  
Imaging Biomarkers ◽  
Great Promise ◽  
Non Invasive ◽  
Quantitative Image ◽  
Artery Disease ◽  
Therapeutic Decision Making ◽  
Underlying Pathophysiology

Radiomics, via the extraction of quantitative information from conventional radiologic images, can identify imperceptible imaging biomarkers that can advance the characterization of coronary plaques and the surrounding adipose tissue. Such an approach can unravel the underlying pathophysiology of atherosclerosis which has the potential to aid diagnostic, prognostic and, therapeutic decision making. Several studies have demonstrated that radiomic analysis can characterize coronary atherosclerotic plaques with a level of accuracy comparable, if not superior, to current conventional qualitative and quantitative image analysis. While there are many milestones still to be reached before radiomics can be integrated into current clinical practice, such techniques hold great promise for improving the imaging phenotyping of coronary artery disease.

scholarly journals Machine learning powered ellipsometry

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Jinchao Liu ◽  
Di Zhang ◽  
Dianqiang Yu ◽  
Mengxin Ren ◽  
Jingjun Xu
Keyword(s):  
Machine Learning ◽  
Optical Constants ◽  
Optical Characterization ◽  
Superior Performance ◽  
Trial And Error ◽  
Powerful Method ◽  
Human In The Loop ◽  
Ill Posed ◽  
Fully Automatic

AbstractEllipsometry is a powerful method for determining both the optical constants and thickness of thin films. For decades, solutions to ill-posed inverse ellipsometric problems require substantial human–expert intervention and have become essentially human-in-the-loop trial-and-error processes that are not only tedious and time-consuming but also limit the applicability of ellipsometry. Here, we demonstrate a machine learning based approach for solving ellipsometric problems in an unambiguous and fully automatic manner while showing superior performance. The proposed approach is experimentally validated by using a broad range of films covering categories of metals, semiconductors, and dielectrics. This method is compatible with existing ellipsometers and paves the way for realizing the automatic, rapid, high-throughput optical characterization of films.

Sign in / Sign up

Export Citation Format

Share Document