scholarly journals Bone Chemical Composition Assessment with Multi-Wavelength Photoacoustic Analysis

2020 ◽  
Vol 10 (22) ◽  
pp. 8214
Author(s):  
Ting Feng ◽  
Yunhao Zhu ◽  
Kenneth M. Kozloff ◽  
Basma Khoury ◽  
Yejing Xie ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Optical Absorption ◽  
Organic Materials ◽  
Spectral Unmixing ◽  
Chemical Components ◽  
Bone Specimen ◽  
Non Invasive ◽  
Multi Wavelength ◽  
Metabolic Activities ◽  
Invasive Evaluation

In this study, the feasibility of assessing the chemical composition in bone using the multi-wavelength photoacoustic analysis (MWPA) method was investigated. By illuminating a bone specimen using laser light with a wavelength tunable over an optical spectrum from 680 nm to 950 nm, the optical absorption spectrum of the bone was acquired. Then, with the optical absorption spectra of all the optically absorbing chemical components in the bone known, a spectral unmixing procedure was performed to quantitatively assess the relative content of each chemical component. The experimental results from porcine rib bones demonstrated that the contents of the chemical components, including not only non-organic materials such as minerals and water but also organic materials including oxygenated hemoglobin, deoxygenated hemoglobin, lipid, and collagen, can all be assessed by MWPA. As the chemical composition in the bone is directly associated with functional and metabolic activities, the finding from this study suggests that the MWPA method could offer a new diagnostic tool for the non-invasive evaluation of bone health.

scholarly journals Bone Chemical Composition Analysis Using Photoacoustic Technique

2020 ◽  
Vol 8 ◽  
Author(s):  
Ting Feng ◽  
Yejing Xie ◽  
Weiya Xie ◽  
Dean Ta ◽  
Qian Cheng
Keyword(s):  
Chemical Composition ◽  
Optical Absorption ◽  
Imaging Techniques ◽  
Diagnostic Technique ◽  
High Sensitivity ◽  
Spectral Unmixing ◽  
Chemical Components ◽  
Composition Analysis ◽  
Feasibility Assessment ◽  
Multi Wavelength

Photoacoustic (PA) signal analysis based on ultrasonic wave detection can provide both high-sensitivity optical contrast information and micro-architectural information which is highly related with the chemical composition of tissue. In this study, the feasibility assessment of bone composition assessment was investigated using the multi-wavelength PA analysis (MWPA) method which could reflect the molecular information. By illuminating a bone specimen using a laser light with wavelength over an optical spectrum ranging from 680 to 950 nm, the optical absorption spectrum of the bone was acquired. Then, with the optical absorption spectra of all optical absorption chemical components in the known bone, a spectral unmixing procedure was performed to quantitatively assess the relative content of each chemical component. The experimental results from rabbit bones show that MWPA method can be used to assess chemical components related to bone metabolism. Our study confirmed that PA technique can be used as a novel bone diagnostic technique by providing new information about the quantity of bone and identifying biomarkers of bone that can improve the current diagnostic imaging techniques.

Ultrasonic Evaluation of "Silent Regions" in the Thyroid Scintiscan

1978 ◽  
Vol 17 (01) ◽  
pp. 16-23 ◽  
Author(s):  
Ch. L. Zollikofer ◽  
J. Wewerka ◽  
Th. Frank
Keyword(s):  
Needle Biopsy ◽  
Clinical Course ◽  
Stimulation Test ◽  
Evaluation Procedure ◽  
Sonographic Diagnosis ◽  
Non Invasive ◽  
Evaluation Procedures ◽  
Ultrasonic Evaluation ◽  
Invasive Evaluation ◽  
Autonomous Adenoma

35 patients with scintigraphically silent thyroid regions without palpable cold nodules were further evaluated by ultrasonography. In 33 cases the sonographic diagnosis was confirmed by other examinations or the clinical course. 2 cases were misinterpreted right at the beginning of our series.The use of ultrasonography in evaluating silent thyroid regions in the totally decompensated autonomous adenoma, in unilateral thyroid aplasia, thyroiditis and hyperthyroidism is shown to be a reliable and valuable supplement to the clinical and radioisotopic evaluation procedures. When differentiating the totally decompensated autonomous adenoma from unilateral thyroid aplasia a stimulation test need not be performed in most cases. Suspected thyroiditis can be confirmed in a simple way. Being a non-invasive evaluation procedure, ultrasonography should be used before performing a needle biopsy.

Three-dimensional speckle-tracking echocardiography – a further step in the non-invasive three-dimensional cardiac imaging

2012 ◽  
Vol 153 (40) ◽  
pp. 1570-1577 ◽  
Author(s):  
Attila Nemes ◽  
Anita Kalapos ◽  
Péter Domsik ◽  
Tamás Forster
Keyword(s):  
Cardiac Imaging ◽  
Speckle Tracking ◽  
Speckle Tracking Echocardiography ◽  
Three Dimensional ◽  
Myocardial Mechanics ◽  
Non Invasive ◽  
Imaging Methodology ◽  
Invasive Evaluation

Three-dimensional speckle-tracking echocardiography is a new cardiac imaging methodology, which allows three-dimensional non-invasive evaluation of the myocardial mechanics. The aim of this review is to present this new tool emphasizing its diagnostic potentials and demonstrating its limitations, as well. Orv. Hetil., 2012, 153, 1570–1577.

scholarly journals The chemical composition of Lessonia berteroana (ex L. nigrescens) in kelp harvest management and open access areas near Coquimbo, Chile

2018 ◽  
Vol 46 (2) ◽  
pp. 258-267
Author(s):  
J.M. Alonso Vega ◽  
Pedro H. Toledo
Keyword(s):  
Resource Management ◽  
Chemical Composition ◽  
Open Access ◽  
Environmental Changes ◽  
Chemical Components ◽  
Optimal Harvesting ◽  
Harvest Management ◽  
Species Population ◽  
Pressure Indicators ◽  
Lessonia Berteroana

Lessonia berteroana (ex L. nigrescens) is kelp freely harvested from Open Access Areas (OAA), and to some extent controlled, from Management and Exploitation Areas for Benthic Resources (MEABR). Harvesting pressures can change population dynamics, mainly in OAAs. In particular, harvesting may alter the chemical components of plants. Therefore, the aim of this study was to determine the harvesting effects on the chemical composition of L. berteroana from MEABR and OAA sampled during different seasons (spring and fall) and at two sites (Talquilla and Lagunillas) near Coquimbo (30°S), Chile. The crude protein (13.5 ± 1.0%), total lipids (0.9 ± 0.2%), crude fiber (16.3 ± 1.6%), ash (30.1 ± 1.5%), and nitrogen-free extract (39.2 ± 2.0%) contents of L. berteroana were within reference values for Laminariales species. Population descriptors and chemical analyses showed that harvesting had local effects, rather than being affected by a resource management strategy (OAA vs MEABR). The seasonal anticipator nature of L. berteroana may explain the detected seasonality of it's chemical composition. Regarding functional morphological structures, chemical composition in the fronds was more variable than in the stipes and perennial holdfast, probably since leaves are ephemeral structures susceptible to environmental changes and that play a functional, rather than structural, role in kelp. In the context of Chilean kelp resource management, monitoring chemical composition is useful for determining optimal harvesting periods to local scale and for deciding when commercially valuable compounds, such as alginate, should be extracted. These data also complement harvesting pressure indicators based on L. berteroana demographic parameters.

scholarly journals Design and Analysis of a Continuous and Non-Invasive Multi-Wavelength Optical Sensor for Measurement of Dermal Water Content

Sensors ◽  
2021 ◽  
Vol 21 (6) ◽  
pp. 2162
Author(s):  
Mohammad Mamouei ◽  
Subhasri Chatterjee ◽  
Meysam Razban ◽  
Meha Qassem ◽  
Panayiotis A. Kyriacou
Keyword(s):  
Water Content ◽  
Optical Sensor ◽  
Broad Band ◽  
Gravimetric Analysis ◽  
Skin Damage ◽  
Biophysical Parameter ◽  
Non Invasive ◽  
Multi Wavelength ◽  
Invasive Measurement

Dermal water content is an important biophysical parameter in preserving skin integrity and preventing skin damage. Traditional electrical-based and open-chamber evaporimeters have several well-known limitations. In particular, such devices are costly, sizeable, and only provide arbitrary outputs. They also do not permit continuous and non-invasive monitoring of dermal water content, which can be beneficial for various consumer, clinical, and cosmetic purposes. We report here on the design and development of a digital multi-wavelength optical sensor that performs continuous and non-invasive measurement of dermal water content. In silico investigation on porcine skin was carried out using the Monte Carlo modeling strategy to evaluate the feasibility and characterize the sensor. Subsequently, an in vitro experiment was carried out to evaluate the performance of the sensor and benchmark its accuracy against a high-end, broad band spectrophotometer. Reference measurements were made against gravimetric analysis. The results demonstrate that the developed sensor can deliver accurate, continuous, and non-invasive measurement of skin hydration through measurement of dermal water content. Remarkably, the novel design of the sensor exceeded the performance of the high-end spectrophotometer due to the important denoising effects of temporal averaging. The authors believe, in addition to wellbeing and skin health monitoring, the designed sensor can particularly facilitate disease management in patients presenting diabetes mellitus, hypothyroidism, malnutrition, and atopic dermatitis.

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