M. Ando, N. Shimada, Kenichiro Asano, T. Kikutsuji, Jun-ichi Ono, K. Jikuya, S. Mochizuki
Objective: To investigate the characteristics of the ratio of extracellular water (ECW) to total body water (TBW) volume (ECW/TBW) in a large group of healthy adults, measured by multi-frequency bioelectrical impedance (bioimpedance) analysis (MF-BIA). Subjects and methods: The correlation between ECW and TBW was studied in 957 healthy adults who underwent general medical examinations. Differences between measured and predicted ECW from ECW–TBW correlation equations (ΔECW) were calculated, and possible factors for non-zero ΔECW were explored. To investigate the influence of percent fat mass (%FM) on ECW/TBW, the ECW/TBW values of “lean” and “obese” groups, classified by %FM, were compared. ECW/TBW was also compared between “non-obese” and “obese class I-II” groups, classified by the body mass index for both genders. Results: ECW and TBW showed strong positive correlations in both genders. ΔECW was within ±0.2 L and increased with advancing age; ECW/ TBW also increased. There were no significant differences in ECW/TBW between the “lean” and “obese” groups in either gender, or between the “non-obese” and “obese class I-II” groups in the female group. Conclusions: ECW/TBW measured by MF-BIA was considered to be an index of body water distribution in healthy adults ranging from “lean” to “obese class I-II,” which is not significantly affected by body fat.
{"title":"Characteristics of body water distribution in healthy adults measured by multi-frequency bioelectrical impedance analysis","authors":"M. Ando, N. Shimada, Kenichiro Asano, T. Kikutsuji, Jun-ichi Ono, K. Jikuya, S. Mochizuki","doi":"10.17106/JBR.33.13","DOIUrl":"https://doi.org/10.17106/JBR.33.13","url":null,"abstract":"Objective: To investigate the characteristics of the ratio of extracellular water (ECW) to total body water (TBW) volume (ECW/TBW) in a large group of healthy adults, measured by multi-frequency bioelectrical impedance (bioimpedance) analysis (MF-BIA). Subjects and methods: The correlation between ECW and TBW was studied in 957 healthy adults who underwent general medical examinations. Differences between measured and predicted ECW from ECW–TBW correlation equations (ΔECW) were calculated, and possible factors for non-zero ΔECW were explored. To investigate the influence of percent fat mass (%FM) on ECW/TBW, the ECW/TBW values of “lean” and “obese” groups, classified by %FM, were compared. ECW/TBW was also compared between “non-obese” and “obese class I-II” groups, classified by the body mass index for both genders. Results: ECW and TBW showed strong positive correlations in both genders. ΔECW was within ±0.2 L and increased with advancing age; ECW/ TBW also increased. There were no significant differences in ECW/TBW between the “lean” and “obese” groups in either gender, or between the “non-obese” and “obese class I-II” groups in the female group. Conclusions: ECW/TBW measured by MF-BIA was considered to be an index of body water distribution in healthy adults ranging from “lean” to “obese class I-II,” which is not significantly affected by body fat.","PeriodicalId":39272,"journal":{"name":"Journal of Biorheology","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.17106/JBR.33.13","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68197672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We have applied an algorithm to improve the accuracy of particle identification and centroid coordinates for each particle image in particle tracking technique. The algorithm introduced two techniques; 1) cutting off by each threshold at the peak in the pixel intensity distribution for each image of local area around the particle, and 2) calculation of the centroid based on pixel intensities in the original image of the particle instead of binarized data. The former properly cuts the noise in the background for each particle which has large variety in level particle by particle due to fluctuating illuminations and out-of-focus particles in the image, and the latter avoids the loss of accuracy by the commonly used binarization. We have demonstrated that the algorithm significantly improves the accuracy in deter mination of centroid coordinates and the correctness in particle identification. We have also validated the advantage of the algorithm in accuracy by applying the algorithm to a sequence of confocal microscopy images of diffusing particles in a polysaccharide solution. This algorithm will be signifi cantly useful in particle tracking technique for biological systems, especially for fluorescence microscopy observa-tions with considerable obstructive stray fluorescent signals. L org,j I sm,j ( m , n ) pixel intensity indexed by ( m , n ) on the x and y axis of L sm,j m = 1, ..., d s pixel row index of L sm,j n = 1, ..., d s pixel column index of L sm,j I T,j calculated cut off intensity of L sm,j L cut,j cut off image of L sm,j I cut,j ( m , n ) pixel intensity indexed by ( m , n ) on the x and y axis of L cut,j C w,j weighted centroid coordinate of L cut,j
在粒子跟踪技术中，我们应用了一种算法来提高粒子识别的精度和每个粒子图像的质心坐标。该算法引入了两种技术;1)在粒子周围局部区域的每张图像像素强度分布的峰值处用每个阈值截断，2)根据粒子原始图像中的像素强度计算质心，而不是根据二值化的数据。前者能很好地去除由于光照波动和图像中散焦粒子等导致的各粒子水平变化较大的背景噪声，后者则避免了常用二值化方法造成的精度损失。实验证明，该算法显著提高了质心坐标的确定精度和粒子识别的准确性。我们还通过将该算法应用于多糖溶液中扩散颗粒的共聚焦显微镜图像序列，验证了该算法在准确性方面的优势。该算法将在生物系统的粒子跟踪技术中发挥重要作用，特别是在具有相当大的杂散荧光信号的荧光显微镜观察中。L org,j I sm,j (m, n)在L sm的x轴和y轴上以(m, n)为索引的像素强度，j m = 1，…， d s L sm的像素行索引，j n = 1，…， d s L - sm的像素列指数，j I T,j L - sm的计算截断强度，j L - cut,j L - sm的截断图像，j I cut,j (m, n) L - cut的x、y轴上(m, n)索引的像素强度，j C w,j L - cut的加权质心坐标，j
{"title":"Accuracy improvement of centroid coordinates and particle identification in particle tracking technique","authors":"Lester C. Geonzon, S. Matsukawa","doi":"10.17106/JBR.33.2","DOIUrl":"https://doi.org/10.17106/JBR.33.2","url":null,"abstract":"We have applied an algorithm to improve the accuracy of particle identification and centroid coordinates for each particle image in particle tracking technique. The algorithm introduced two techniques; 1) cutting off by each threshold at the peak in the pixel intensity distribution for each image of local area around the particle, and 2) calculation of the centroid based on pixel intensities in the original image of the particle instead of binarized data. The former properly cuts the noise in the background for each particle which has large variety in level particle by particle due to fluctuating illuminations and out-of-focus particles in the image, and the latter avoids the loss of accuracy by the commonly used binarization. We have demonstrated that the algorithm significantly improves the accuracy in deter mination of centroid coordinates and the correctness in particle identification. We have also validated the advantage of the algorithm in accuracy by applying the algorithm to a sequence of confocal microscopy images of diffusing particles in a polysaccharide solution. This algorithm will be signifi cantly useful in particle tracking technique for biological systems, especially for fluorescence microscopy observa-tions with considerable obstructive stray fluorescent signals. L org,j I sm,j ( m , n ) pixel intensity indexed by ( m , n ) on the x and y axis of L sm,j m = 1, ..., d s pixel row index of L sm,j n = 1, ..., d s pixel column index of L sm,j I T,j calculated cut off intensity of L sm,j L cut,j cut off image of L sm,j I cut,j ( m , n ) pixel intensity indexed by ( m , n ) on the x and y axis of L cut,j C w,j weighted centroid coordinate of L cut,j","PeriodicalId":39272,"journal":{"name":"Journal of Biorheology","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.17106/JBR.33.2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68197696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Fujimura, M. Shojima, S. Nemoto, Yasuyuki Umeda, T. Yamada, Takumi Ishii, F. Wakabayashi
Various coil modeling techniques have been applied for computational fluid dynamics (CFD) analysis to predict recanalization after aneurysm coil embolization. Investigation on the technical difficulties and the effects on CFD analysis results when using the four main coil modeling methods (solid model, porous model, Dynamic Path Planning, finite element method (FEM) structural analysis) revealed that the expertise required for the analysis as well as the time needed for the analysis increased the more the results were realistic. In addition, by applying the four coil modeling methods to cases that actually underwent coil embolization surgery, hemodynamic factors such as blood flow velocity or mass flow rate were reported to have an effect on the occurrence of recanalization. It was also reported that the consideration of hemodynamic factors is useful for predicting recanalization. Although various validations are required, CFD analysis may be a useful tool for predicting recanalization of aneurysms after coil embolization in the future.
{"title":"Numerical simulation techniques to predict aneurysm recanalization after coil embolization and their problems","authors":"S. Fujimura, M. Shojima, S. Nemoto, Yasuyuki Umeda, T. Yamada, Takumi Ishii, F. Wakabayashi","doi":"10.17106/jbr.33.65","DOIUrl":"https://doi.org/10.17106/jbr.33.65","url":null,"abstract":"Various coil modeling techniques have been applied for computational fluid dynamics (CFD) analysis to predict recanalization after aneurysm coil embolization. Investigation on the technical difficulties and the effects on CFD analysis results when using the four main coil modeling methods (solid model, porous model, Dynamic Path Planning, finite element method (FEM) structural analysis) revealed that the expertise required for the analysis as well as the time needed for the analysis increased the more the results were realistic. In addition, by applying the four coil modeling methods to cases that actually underwent coil embolization surgery, hemodynamic factors such as blood flow velocity or mass flow rate were reported to have an effect on the occurrence of recanalization. It was also reported that the consideration of hemodynamic factors is useful for predicting recanalization. Although various validations are required, CFD analysis may be a useful tool for predicting recanalization of aneurysms after coil embolization in the future.","PeriodicalId":39272,"journal":{"name":"Journal of Biorheology","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68197284","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
T. Yagi, F. Ishida, M. Shojima, H. Anzai, Souichiro Fujimura, T. Sano, Shun Shinozaki, Yuuma Yamanaka, Yuuto Yamamoto, Y. Okamoto, M. Ohta, Masanori Nakamura
Researchers have aimed to identify unruptured intracranial aneurysms at a higher risk of rupture during follow-up for a long time. Computational fluid dynamics has been used widely to identify a hemodynamic discriminator between ruptured and unruptured aneurysms. However, this method has yet to reach a consensus between groups, which may be due, in part, to the significant degrees of freedom in hemodynamic indexes and computational workflows. The present review aims to characterize the degree of association between ruptured aneurysms and hemodynamic indexes, as well as the degree of variability between groups. A PubMed search identified 588 relevant studies. Thirteen met our criteria, yielding a total of 3,692 aneurysms. The definition of hemodynamic indexes were first carefully assessed and then classified accordingly. The variability of hemodynamic indexes between groups displayed a significant indexdependent nature. Normalizing hemodynamic indexes was an effective measure of reducing variability. Hemodynamic indexes were evaluated for associability and quantifiability. Overall, in an attempt to advance the diagnostic performance of hemodynamic indexes, these results shed light on the poor ability to interpret hemodynamic states pathologically. Future studies should incorporate the pathological significance of hemodynamic states into the design of hemodynamic indexes.
{"title":"Systematic review of hemodynamic discriminators for ruptured intracranial aneurysms","authors":"T. Yagi, F. Ishida, M. Shojima, H. Anzai, Souichiro Fujimura, T. Sano, Shun Shinozaki, Yuuma Yamanaka, Yuuto Yamamoto, Y. Okamoto, M. Ohta, Masanori Nakamura","doi":"10.17106/jbr.33.53","DOIUrl":"https://doi.org/10.17106/jbr.33.53","url":null,"abstract":"Researchers have aimed to identify unruptured intracranial aneurysms at a higher risk of rupture during follow-up for a long time. Computational fluid dynamics has been used widely to identify a hemodynamic discriminator between ruptured and unruptured aneurysms. However, this method has yet to reach a consensus between groups, which may be due, in part, to the significant degrees of freedom in hemodynamic indexes and computational workflows. The present review aims to characterize the degree of association between ruptured aneurysms and hemodynamic indexes, as well as the degree of variability between groups. A PubMed search identified 588 relevant studies. Thirteen met our criteria, yielding a total of 3,692 aneurysms. The definition of hemodynamic indexes were first carefully assessed and then classified accordingly. The variability of hemodynamic indexes between groups displayed a significant indexdependent nature. Normalizing hemodynamic indexes was an effective measure of reducing variability. Hemodynamic indexes were evaluated for associability and quantifiability. Overall, in an attempt to advance the diagnostic performance of hemodynamic indexes, these results shed light on the poor ability to interpret hemodynamic states pathologically. Future studies should incorporate the pathological significance of hemodynamic states into the design of hemodynamic indexes.","PeriodicalId":39272,"journal":{"name":"Journal of Biorheology","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.17106/jbr.33.53","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68197280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Shimano, Shota Serigano, Naoki Ikeda, Tomoki Yuchi, Suguru Shiratori, H. Nagano
Computational fluid dynamics (CFD) is considered to be a promising tool for haemodynamic analysis of the intracranial aneurysm. However, aneurysm CFD is still not regarded as fully reliable mainly because the computational result is influenced by too many factors such as the luminal geometry of the model, spatiotemporal resolutions and boundary conditions. Among the influential factors, this paper focuses on outflow boundary conditions used when the computational domain has multiple outlets. Four outflow strategies found in published articles are reviewed: 1) pre-scription of constant or zero pressure, 2) flow splitting based on the power law, 3) traction-free and zero velocity-gradient conditions and 4) coupling of CFD with a reduced-order model. None of them has proved definitely superior or inferior to others. For accurate quantification of the haemodynamic state in the aneurysm, it is crucial to incorporate the physiologically correct flow splitting ratio in CFD analysis by means of accurate specification of pressure or flow rate at the outlets. A coupling of CFD and a 0-d model (a subtype of the reduced-order model) appears to be the most promising although further study is necessary to achieve accurate estimation of model parameters.
{"title":"Understanding of boundary conditions imposed at multiple outlets in computational haemodynamic analysis of cerebral aneurysm","authors":"K. Shimano, Shota Serigano, Naoki Ikeda, Tomoki Yuchi, Suguru Shiratori, H. Nagano","doi":"10.17106/jbr.33.32","DOIUrl":"https://doi.org/10.17106/jbr.33.32","url":null,"abstract":"Computational fluid dynamics (CFD) is considered to be a promising tool for haemodynamic analysis of the intracranial aneurysm. However, aneurysm CFD is still not regarded as fully reliable mainly because the computational result is influenced by too many factors such as the luminal geometry of the model, spatiotemporal resolutions and boundary conditions. Among the influential factors, this paper focuses on outflow boundary conditions used when the computational domain has multiple outlets. Four outflow strategies found in published articles are reviewed: 1) pre-scription of constant or zero pressure, 2) flow splitting based on the power law, 3) traction-free and zero velocity-gradient conditions and 4) coupling of CFD with a reduced-order model. None of them has proved definitely superior or inferior to others. For accurate quantification of the haemodynamic state in the aneurysm, it is crucial to incorporate the physiologically correct flow splitting ratio in CFD analysis by means of accurate specification of pressure or flow rate at the outlets. A coupling of CFD and a 0-d model (a subtype of the reduced-order model) appears to be the most promising although further study is necessary to achieve accurate estimation of model parameters.","PeriodicalId":39272,"journal":{"name":"Journal of Biorheology","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.17106/jbr.33.32","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68197737","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Fukuda, Y. Shimogonya, Masanori Nakamura, T. Yamada, Kosuke Suzuki, Yuuto Yamamoto, K. Kanou, N. Okada, Fangjia Pan, T. Okudaira, Shuntaro Kuwahara
A cerebral aneurysm is a vascular condition characterized by local ballooning of an artery in the brain. Although aneurysm formation and growth are thought to be the result of destruction of the blood vessel wall, the details of the etiology are unclear. We review the formation and growth of cerebral aneurysms as follows. In the first part, we summarize the history of theories on the pathogenesis of cerebral aneurysm in chronological order from epidemiological and pathological viewpoints and based on data obtained from animal models of experimentally induced cerebral aneurysms, with a focus on the involvement of hemodynamic stress on the arterial wall. In the second part, we review computational fluid dynamics (CFD) studies on the initiation of cerebral aneurysms with a brief overview of the history of CFD in hemodynamics analysis. Of the hypotheses presented, strong emphasis is placed on that of high wall shear stress and a high wall shear stress gradient. Other leading hypotheses involving hemodynamics-related parameters are also reviewed. In the third part, we review CFD studies on the growth of cerebral aneurysms, in which hemodynamic parameters were compared between growing and stable aneurysms, to highlight the hemodynamic characteristics associated with their growth.
{"title":"Review on the formation and growth of cerebral aneurysms","authors":"S. Fukuda, Y. Shimogonya, Masanori Nakamura, T. Yamada, Kosuke Suzuki, Yuuto Yamamoto, K. Kanou, N. Okada, Fangjia Pan, T. Okudaira, Shuntaro Kuwahara","doi":"10.17106/jbr.33.43","DOIUrl":"https://doi.org/10.17106/jbr.33.43","url":null,"abstract":"A cerebral aneurysm is a vascular condition characterized by local ballooning of an artery in the brain. Although aneurysm formation and growth are thought to be the result of destruction of the blood vessel wall, the details of the etiology are unclear. We review the formation and growth of cerebral aneurysms as follows. In the first part, we summarize the history of theories on the pathogenesis of cerebral aneurysm in chronological order from epidemiological and pathological viewpoints and based on data obtained from animal models of experimentally induced cerebral aneurysms, with a focus on the involvement of hemodynamic stress on the arterial wall. In the second part, we review computational fluid dynamics (CFD) studies on the initiation of cerebral aneurysms with a brief overview of the history of CFD in hemodynamics analysis. Of the hypotheses presented, strong emphasis is placed on that of high wall shear stress and a high wall shear stress gradient. Other leading hypotheses involving hemodynamics-related parameters are also reviewed. In the third part, we review CFD studies on the growth of cerebral aneurysms, in which hemodynamic parameters were compared between growing and stable aneurysms, to highlight the hemodynamic characteristics associated with their growth.","PeriodicalId":39272,"journal":{"name":"Journal of Biorheology","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.17106/jbr.33.43","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68197740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Intracranial aneurysm (IA) can cause a lethal subarachnoid hemorrhage after rupture. Thereby, the correct understanding of the pathogenesis of the disease is essential to develop a novel therapeutic strategy to prevent progression. The accumulating evidence from simulation of hemodynamics targeting human cases has implied the role of hemodynamic force in IAs. In another point of view, experimental evidence mainly from animal studies has clarified the crucial role of macrophage-mediated long lasting-inflammation in the pathogenesis. However, how hemody namic stress triggers such molecular events in arterial walls to develop IAs remains unclear. Recent experimental studies have revealed some of the potential machineries regulating hemodynamic stress-triggered IA formation. High walls shear stress activates endothelial cells and induces expression of MCP-1 at the earliest stage of IA formation. At adventitia, mechanical stretch induces MCP-1 expression in fibroblasts as well. MCP-1-mediated infiltration of macrophages into intracranial arterial walls thus occurs. In infiltrating macrophages, EP2 functions to exacerbate inflammation through formation of positive feedback loop, synergistic action with TNF-α and auto-amplification loop among macrophages. Given the nature of IAs as a vascular disease, further studies focused on hemodynamic force-mediated molecular events regulating the pathogenesis are necessary to understand the whole picture of the disease.
{"title":"Molecular events regulating the pathogenesis of intracranial aneurysms: Special insight on hemodynamics and chronic inflammation","authors":"T. Aoki","doi":"10.17106/jbr.33.28","DOIUrl":"https://doi.org/10.17106/jbr.33.28","url":null,"abstract":"Intracranial aneurysm (IA) can cause a lethal subarachnoid hemorrhage after rupture. Thereby, the correct understanding of the pathogenesis of the disease is essential to develop a novel therapeutic strategy to prevent progression. The accumulating evidence from simulation of hemodynamics targeting human cases has implied the role of hemodynamic force in IAs. In another point of view, experimental evidence mainly from animal studies has clarified the crucial role of macrophage-mediated long lasting-inflammation in the pathogenesis. However, how hemody namic stress triggers such molecular events in arterial walls to develop IAs remains unclear. Recent experimental studies have revealed some of the potential machineries regulating hemodynamic stress-triggered IA formation. High walls shear stress activates endothelial cells and induces expression of MCP-1 at the earliest stage of IA formation. At adventitia, mechanical stretch induces MCP-1 expression in fibroblasts as well. MCP-1-mediated infiltration of macrophages into intracranial arterial walls thus occurs. In infiltrating macrophages, EP2 functions to exacerbate inflammation through formation of positive feedback loop, synergistic action with TNF-α and auto-amplification loop among macrophages. Given the nature of IAs as a vascular disease, further studies focused on hemodynamic force-mediated molecular events regulating the pathogenesis are necessary to understand the whole picture of the disease.","PeriodicalId":39272,"journal":{"name":"Journal of Biorheology","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68197732","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hao Zhang, N. Fujiwara, Masaharuo Kobayashi, S. Yamada, F. Liang, S. Takagi, M. Oshima
The hemodynamics of blood flow in the Circle of Willis (CoW) is considered to be important for the understanding of disease progression in cerebral circulation. In this research, we developed a method by combining 1D-0D model with the medical imaging data of magnetic resonance imaging (MRI) and single photon emission computed tomography (SPECT), in order to investigate the hemodynamics in CoW. The MRI data was used as the arterial geometry parameter for 1D model. The SPECT data was used as the reference data for the flow rates at the efferent arteries of CoW, which indicated if adjustment needed to be made to the peripheral cerebral resistance for 0D model. We applied our method to two patients and compared the simulation results with PC-MRI measurement data. The comparison showed the differences of flow distribution in the afferent arteries between simulation results and measurement data were 0.6–6.0% and 5.7–13.2% respectively in two cases. Both simulations captured the individual difference of flow distribution in the CoW. The results suggested that our method can be used to obtain the hemodynamics information in the CoW for an individual patient.
{"title":"Development of patient-specific 1D-0D simulation based on MRI and SPECT data","authors":"Hao Zhang, N. Fujiwara, Masaharuo Kobayashi, S. Yamada, F. Liang, S. Takagi, M. Oshima","doi":"10.17106/JBR.32.2","DOIUrl":"https://doi.org/10.17106/JBR.32.2","url":null,"abstract":"The hemodynamics of blood flow in the Circle of Willis (CoW) is considered to be important for the understanding of disease progression in cerebral circulation. In this research, we developed a method by combining 1D-0D model with the medical imaging data of magnetic resonance imaging (MRI) and single photon emission computed tomography (SPECT), in order to investigate the hemodynamics in CoW. The MRI data was used as the arterial geometry parameter for 1D model. The SPECT data was used as the reference data for the flow rates at the efferent arteries of CoW, which indicated if adjustment needed to be made to the peripheral cerebral resistance for 0D model. We applied our method to two patients and compared the simulation results with PC-MRI measurement data. The comparison showed the differences of flow distribution in the afferent arteries between simulation results and measurement data were 0.6–6.0% and 5.7–13.2% respectively in two cases. Both simulations captured the individual difference of flow distribution in the CoW. The results suggested that our method can be used to obtain the hemodynamics information in the CoW for an individual patient.","PeriodicalId":39272,"journal":{"name":"Journal of Biorheology","volume":"32 1","pages":"2-8"},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.17106/JBR.32.2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68197116","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Ando, Tomota Suminaka, N. Shimada, Kenichiro Asano, Jun-ichi Ono, K. Jikuya, S. Mochizuki
The ratio of the volumes of extracellular water to total body water (ECW/TBW) obtained by multi-frequency bioelectrical impedance analysis (MF-BIA) indicates body water balance. However, the characteristics of ECW/TBW in hemodialysis (HD) patients have not been fully investigated yet. We evaluated correlations of ECW/TBW with body composition, circulatory and body fluid status, and nutritional status in 60 stable maintenance HD patients using MF-BIA. ECW/TBW increased with increasing age and showed significant positive correlations with volume index (VI), cardiothoracic ratio, and brain natriuretic peptide, all of which are indices of circulatory and body fluid status. Furthermore, there were significant negative correlations between ECW/TBW and serum albumin (Alb), the geriatric nutritional risk index, and the normalized protein catabolic rate, all of which indicate nutritional status. Following multiple regression analysis, the independently related factors for total subjects were age, VI, and Alb. In obese HD patients, ECW/TBW tended to decrease, indicating intravascular dehydration. In conclusion, ECW/TBW in HD patients was shown to increase with age and can reflect circulatory, body fluid, and nutritional status, as well as the difference between predetermined dry weight and “optimal body weight” which may change along with a patient’s nutritional status.
{"title":"Body water balance in hemodialysis patients reflects nutritional, circulatory, and body fluid status","authors":"M. Ando, Tomota Suminaka, N. Shimada, Kenichiro Asano, Jun-ichi Ono, K. Jikuya, S. Mochizuki","doi":"10.17106/JBR.32.46","DOIUrl":"https://doi.org/10.17106/JBR.32.46","url":null,"abstract":"The ratio of the volumes of extracellular water to total body water (ECW/TBW) obtained by multi-frequency bioelectrical impedance analysis (MF-BIA) indicates body water balance. However, the characteristics of ECW/TBW in hemodialysis (HD) patients have not been fully investigated yet. We evaluated correlations of ECW/TBW with body composition, circulatory and body fluid status, and nutritional status in 60 stable maintenance HD patients using MF-BIA. ECW/TBW increased with increasing age and showed significant positive correlations with volume index (VI), cardiothoracic ratio, and brain natriuretic peptide, all of which are indices of circulatory and body fluid status. Furthermore, there were significant negative correlations between ECW/TBW and serum albumin (Alb), the geriatric nutritional risk index, and the normalized protein catabolic rate, all of which indicate nutritional status. Following multiple regression analysis, the independently related factors for total subjects were age, VI, and Alb. In obese HD patients, ECW/TBW tended to decrease, indicating intravascular dehydration. In conclusion, ECW/TBW in HD patients was shown to increase with age and can reflect circulatory, body fluid, and nutritional status, as well as the difference between predetermined dry weight and “optimal body weight” which may change along with a patient’s nutritional status.","PeriodicalId":39272,"journal":{"name":"Journal of Biorheology","volume":"32 1","pages":"46-55"},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.17106/JBR.32.46","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68197276","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Higashimori, A. Shibata, Akira Ikegami, M. Nakauma, K. Hori, T. Ono
This paper describes a spatiotemporal analysis of tongue behavior while eating a nursing-care gel-like food. First, tongue pressure while eating the gel-like food is measured using a multipoint pressure sensor attached to the palate. By considering a pressure waveform as a half sinusoidal wave, a Lissajous curve drawn with two pressure waveforms measured at two points can be used to analyze tongue behavior. Based on the curve, three feature values can be designed to characterize tongue behavior: pressure level, pressure distribution, and pressure phase difference. Finally, correlations between the feature values and the sensory evaluation of the texture are visualized. The proposed method is a potentially useful tool for investigating the relationship between tongue behavior and the texture of food.
{"title":"Half-wave Lissajous curve analysis of tongue pressure while eating gel-like food","authors":"M. Higashimori, A. Shibata, Akira Ikegami, M. Nakauma, K. Hori, T. Ono","doi":"10.17106/JBR.32.39","DOIUrl":"https://doi.org/10.17106/JBR.32.39","url":null,"abstract":"This paper describes a spatiotemporal analysis of tongue behavior while eating a nursing-care gel-like food. First, tongue pressure while eating the gel-like food is measured using a multipoint pressure sensor attached to the palate. By considering a pressure waveform as a half sinusoidal wave, a Lissajous curve drawn with two pressure waveforms measured at two points can be used to analyze tongue behavior. Based on the curve, three feature values can be designed to characterize tongue behavior: pressure level, pressure distribution, and pressure phase difference. Finally, correlations between the feature values and the sensory evaluation of the texture are visualized. The proposed method is a potentially useful tool for investigating the relationship between tongue behavior and the texture of food.","PeriodicalId":39272,"journal":{"name":"Journal of Biorheology","volume":"32 1","pages":"39-45"},"PeriodicalIF":0.0,"publicationDate":"2018-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.17106/JBR.32.39","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68196781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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