Technology and Health Care - Volume 24, issue s2

Authors: Choi, Jeong Ryeol | Kim, Daeyeoul | Menouar, Salah | Sever, Ramazan | Abdalla, M. Sebawe

Article Type: Research Article

Abstract: BACKGROUND: Propagation of photon signals in biological systems, such as neurons, accompanies the production of biophotons. The role of biophotons in a cell deserves special attention because it can be applied to diverse optical systems. OBJECTIVE: This work has been aimed to investigate the time behavior of biophoton signals emitted from living systems in detail, by introducing a Hamiltonian that describes the process. The ratio of the energy loss during signal dissipation will also be investigated. METHOD: To see the adiabatic properties of the biophoton signal, we introduced an adiabatic invariant of …the system according to the method of its basic formulation. RESULTS: The energy of the released biophoton dissipates over time in a somewhat intricate way when t is small. However, after a sufficient long time, it dissipates in proportion (1+λ_0t)^2 to where λ_0 is a constant that is relevant to the degree of dissipation. We have confirmed that the energy of the biophoton signal oscillates in a particular way while it dissipates. CONCLUSION: This research clarifies the characteristics of radiation fields associated with biophotons on the basis of Hamiltonian dynamics which describes phenomenological aspects of biophotons signals. Show more

Keywords: Biophoton, energy dissipation, hamiltonian, damped harmonic oscillator, biological system

DOI: 10.3233/THC-161184

Citation: Technology and Health Care, vol. 24, no. s2, pp. S577-S585, 2016

Authors: Gyalai, Zsolt | Jeremiás, Zsuzsanna | Baricz, Emoke | Rudzik, Roxana | Dobreanu, Dan

Article Type: Research Article

Abstract: The aim of this study is to observe the differences between mechanical and electrical dyssynchrony in patients with impaired systolic ventricular function and symptomatic heart failure and to highlight the importance of mechanical dyssynchrony besides electrical dyssynchrony in clinical guidelines and clinical practice. Fifty-eight patients with heart failure, who are with the New York Heart Association (NYHA) functional class II-IV and left ventricular ejection fraction (LVEF) under 35%, were enrolled. Patients were divided into two groups, according to the duration of QRS complex (> 120 ms and ≤ 120 ms respectively). Echocardiographic parameters of interventricular (interventricular mechanical delay - IMD) …and intraventricular (septal-to-posterior wall motion delay - SPWMD) dyssynchrony were measured in both groups. Results indicate that the duration of the QRS complex (i.e. electrical dyssynchrony) is not a fully reliable indicator of ventricular dyssynchrony; therefore ecocardiographic evaluation of mechanical dyssynchrony should also be recommended for better selection of candidates for cardiac resynchronization therapy (CRT). Show more

Keywords: Ventricular dyssynchrony, heart failure, echocardiography, cardiac resynchronization therapy (CRT)

DOI: 10.3233/THC-161185

Citation: Technology and Health Care, vol. 24, no. s2, pp. S587-S592, 2016

Authors: Huang, Jianping | Wang, Lihui | Chu, Chunyu | Zhang, Yanli | Liu, Wanyu | Zhu, Yuemin

Article Type: Research Article

Abstract: Diffusion tensor magnetic resonance (DTMR) imaging and diffusion tensor imaging (DTI) have been widely used to probe noninvasively biological tissue structures. However, DTI suffers from long acquisition times, which limit its practical and clinical applications. This paper proposes a new Compressed Sensing (CS) reconstruction method that employs joint sparsity and rank deficiency to reconstruct cardiac DTMR images from undersampled k-space data. Diffusion-weighted images acquired in different diffusion directions were firstly stacked as columns to form the matrix. The matrix was row sparse in the transform domain and had a low rank. These two properties were then incorporated into the CS …reconstruction framework. The underlying constrained optimization problem was finally solved by the first-order fast method. Experiments were carried out on both simulation and real human cardiac DTMR images. The results demonstrated that the proposed approach had lower reconstruction errors for DTI indices, including fractional anisotropy (FA) and mean diffusivities (MD), compared to the existing CS-DTMR image reconstruction techniques. Show more

Keywords: Diffusion tensor imaging, compressed sensing, low rank, sparsity constraint

DOI: 10.3233/THC-161186

Citation: Technology and Health Care, vol. 24, no. s2, pp. S593-S599, 2016

Authors: Lim, Jongwoo | Wang, Bohyun | Lim, Joon S.

Article Type: Research Article

Abstract: Finding the minimum number of appropriate biomarkers for specific targets such as a lung cancer has been a challenging issue in bioinformatics. We propose a hierarchical two-phase framework for selecting appropriate biomarkers that extracts candidate biomarkers from the cancer microarray datasets and then selects the minimum number of appropriate biomarkers from the extracted candidate biomarkers datasets with a specific neuro-fuzzy algorithm, which is called a neural network with weighted fuzzy membership function (NEWFM). In this context, as the first phase, the proposed framework is to extract candidate biomarkers by using a Bhattacharyya distance method that measures the similarity of two …discrete probability distributions. Finally, the proposed framework is able to reduce the cost of finding biomarkers by not receiving medical supplements and improve the accuracy of the biomarkers in specific cancer target datasets. Show more

Keywords: Microarray data, feature selection, neuro network fuzzy algorithm

DOI: 10.3233/THC-161187

Citation: Technology and Health Care, vol. 24, no. s2, pp. S601-S605, 2016

Authors: Eom, Su-Hong | Lee, Eung-Hyuk

Article Type: Research Article

Abstract: BACKGROUND: For implementing autonomous rehabilitation exercises for upper limb hemiplegic patients, interfaces and a rehabilitation scenario that allow lateral and bilateral motions in a rehabilitation exercise robot are proposed. OBJECTIVE: The proposed method measures the motion information generated from the unaffected part and projects it to an affected part in which the affected part expresses motions of the unaffected part. METHODS: Both the accelerometer and gyro data were merged for estimating the motion information of the unaffected part. Also, HDR and complementary filters were applied to improve measurement errors in a data merging …process. RESULTS: For verifying the proposed method, a device, which is similar to a human body joint, was fabricated. Then, the angular values estimated by using an inertial sensor and the encoder values from the device were compared. In addition, a camera analysis was used to verify the proposed rehabilitation scenario by applying the rehabilitation interface proposed in this study to an exo-skeleton robot arm. CONCLUSION: It is possible to apply the method proposed in this study to the control variables in different upper limb rehabilitation exercise robots. Thus, it is expected that patient centered active lateral/bilateral rehabilitation exercises can be performed through this interface method. Show more

Keywords: Lateral and bilateral upper limb movement, upper limb rehabilitation, active rehabilitation, rehabilitation interface

DOI: 10.3233/THC-161188

Citation: Technology and Health Care, vol. 24, no. s2, pp. S607-S623, 2016

Authors: Li, Xin | Zhong, Yongmin | Subic, Aleksandar | Jazar, Reza | Smith, Julian | Gu, Chengfan

Article Type: Research Article

Abstract: This paper presents a method to characterize tissue thermal damage by taking into account the thermal-mechanical effect of soft tissues for thermal ablation. This method integrates the bio-heating conduction and non-rigid motion dynamics to describe thermal-mechanical behaviors of soft tissues and further extends the traditional tissue damage model to characterize thermal-mechanical damage of soft tissues. Simulations and comparison analysis demonstrate that the proposed method can effectively predict tissue thermal damage and it also provides reliable guidelines for control of the thermal ablation procedure.

Keywords: Tissue thermal damage, bio-heat transfer, tissue thermo-mechanical behaviors, thermal ablation

DOI: 10.3233/THC-161189

Citation: Technology and Health Care, vol. 24, no. s2, pp. S625-S629, 2016

Authors: Li, Hong | Bao, Nan | Xu, Xieping | Zhang, Yaonan | Jin, Shikai | Jin, Yueming | Sun, Haoran

Article Type: Research Article

Abstract: BACKGROUND: Kidney function assessment from renography has great potential for clinical diagnosis. Compartment models are the main analytical models in this field and the vascular compartment is the most important one, whether in the two-compartment model or three-compartment model. Currently, there are some published research studies on renal cortex segmentation. However, there are few publications introducing the methods on how to segment the vascular compartment yet. OBJECTIVE: The objective of this paper is to segment the vascular compartment automatically. METHODS: This method was tested on multi-phase scan images. A feature image reconstructed from …the original images was used to segment the vascular compartment. It used the features of the time-density curve of each voxel in the contrast-enhanced images to distinguish vascular space from other areas. RESULTS: The segmentation result was evaluated by the renal glomerular filtration rate (GFR) analysis of a two-compartment model with the Patlak-Rutland technique. The dataset contained 11 kidney subjects whose GFR ranged from 19.8 ml/min to 74.9 ml/min. The results showed that the correlation between reference GFR and model derived GFR was 0.919 (P< 0.001). CONCLUSION: Compared with segmentation performed on certain phase images, this method can avoid the problem of subjective phase selection. For a given kidney data, the proposed method can always obtain the same segmentation result automatically. Show more

Keywords: Renal function, GFR, renography, vascular compartment segmentation, time density curve, contrast-enhanced image

DOI: 10.3233/THC-161190

Citation: Technology and Health Care, vol. 24, no. s2, pp. S631-S639, 2016

Authors: Zhang, Yudong | Ji, Genlin | Yang, Jiquan | Wang, Shuihua | Dong, Zhengchao | Phillips, Preetha | Sun, Ping

Article Type: Research Article

Abstract: It is important to detect abnormal brains accurately and early. The wavelet-energy (WE) was a successful feature descriptor that achieved excellent performance in various applications; hence, we proposed a WE based new approach for automated abnormal detection, and reported its preliminary results in this study. The kernel support vector machine (KSVM) was used as the classifier, and quantum-behaved particle swarm optimization (QPSO) was introduced to optimize the weights of the SVM. The results based on a 5 × 5-fold cross validation showed the performance of the proposed WE + QPSO-KSVM was superior to ``DWT + PCA + BP-NN'', ``DWT + …PCA + RBF-NN'', ``DWT + PCA + PSO-KSVM'', ``WE + BPNN'', ``WE +$ KSVM'', and ``DWT $+$ PCA $+$ GA-KSVM'' w.r.t. sensitivity, specificity, and accuracy. The work provides a novel means to detect abnormal brains with excellent performance. Show more

Keywords: Magnetic resonance imaging, particle swarm optimization, quantum-behaved PSO, wavelet energy

DOI: 10.3233/THC-161191

Citation: Technology and Health Care, vol. 24, no. s2, pp. S641-S649, 2016

Authors: Zhang, Ruowen | Wang, Yilin | Zhu, Dong | Dong, Fengying | Chen, Xi

Article Type: Research Article

Abstract: BACKGROUND: In this study, the authors cultivated ECV-304 in vitro and incubated cells with H2 O2 , established injury models, and induced oxidized endothelial cell apoptosis. This model makes it possible to choose suitable concentrations of North Schisandra Lignans. OBJECTIVE: To study the protective effects of North Schisandra Lignans on human umbilical vein endothelial cell injuries. METHODS: Endothelial cell growth and proliferation activity were detected through the MTT method. The colorimetric method was used to determine superoxide dismutase (SOD) activity in the cell culture solution, as well as malondialdehyde (MDA) content …in the cell. RESULTS: North Schisandra Lignans noticeably decreased ECV-304 cell injury induced by H2 O2 . Moderate and high concentrations of North Schisandra Lignans could significantly lower MDA content and heighten SOD activity. These differences were significant compared to the H2 O2 group (P< 0.05). CONCLUSIONS: North Schisandra Lignans had an obvious protective effect on ECV-304 injured by H2 O2 $. The mechanism decreases MDA production and heightened SOD activity. Show more

Keywords: North Schisandra Lignans, vascular endothelial cell, superoxide dismutase, malondialdehyde

DOI: 10.3233/THC-161192

Citation: Technology and Health Care, vol. 24, no. s2, pp. S651-S657, 2016

Authors: Seo, Jeongwoo | Choi, Jinseung | Kang, Dongwon | Yang, Seungtae | Kim, Daehyeok | Tack, Gyerae

Article Type: Research Article

Abstract: BACKGROUND: As it is not easy to investigate various variables that affect exercise efficacies and cause injuries while pedaling in the actual experiment, especially for the elderly, the musculoskeletal model simulation with a comparison of measured electromyography (EMG) data could be used to minimize experimental trials. OBJECTIVE: The measured EMG data were compared with the muscle activities from the musculoskeletal model through forward (FD) and inverse dynamic (ID) analysis. METHODS: EMG was measured from eight young adult (20's) and eight elderly (70's) in three minutes pedaling with a constant load and …40 revolutions per minute (RPM) cadence. The muscles used for the analysis were the VastusLateralis, Tibialis Anterior, Bicep Femoris, and Gastrocnemius Medial. Pearson's correlation coefficients of the muscle activity patterns, on-off set, and peak timing at the maximum muscle activity were calculated and compared. BIKE3D and GaitLowerExtremity model were used for the FD and ID simulation. RESULTS: There are significant correlations in the muscle activity patterns except in the case of Biceps Femoris muscle by ID. Thus, it can be concluded that muscle activities of model & EMG showed similar results. CONCLUSION: The result shows that it could be possible to use the musculoskeletal model for various pedaling simulations. Show more

Keywords: Musculoskeletal modeling, electromyography, pedaling, aging

DOI: 10.3233/THC-161193

Citation: Technology and Health Care, vol. 24, no. s2, pp. S659-S664, 2016

Authors: Cao, C.H. | Cao, H.L.

Article Type: Research Article

Abstract: BACKGROUND: With the rapid development of modern medical imaging technology, medical image classification has become more important for medical diagnosis and treatment. OBJECTIVE: To solve the existence of polysemous words and synonyms problem, this study combines the word bag model with PLSA (Probabilistic Latent Semantic Analysis) and proposes the PLSA-BOW (Probabilistic Latent Semantic Analysis-Bag of Words) model. METHODS: In this paper we introduce the bag of words model in text field to image field, and build the model of visual bag of words model. RESULTS: The method enables the word …bag model-based classification method to be further improved in accuracy. CONCLUSIONS: The experimental results show that the PLSA-BOW model for medical image classification can lead to a more accurate classification. Show more

Keywords: Medical image classification, bag of words model, PLSA

DOI: 10.3233/THC-161194

Citation: Technology and Health Care, vol. 24, no. s2, pp. S665-S674, 2016

Authors: Du, Yongxing | Zhang, Lingze | Sang, Lulu | Wu, Daocheng

Article Type: Research Article

Abstract: In this paper, an Archimedean planar spiral antenna for the application of thermotherapy was designed. This type of antenna was chosen for its compact structure, flexible application and wide heating area. The temperature field generated by the use of this Two-armed Spiral Antenna in a muscle-equivalent phantom was simulated and subsequently validated by experimentation. First, the specific absorption rate (SAR) of the field was calculated using the Finite Element Method (FEM) by Ansoft's High Frequency Structure Simulation (HFSS). Then, the temperature elevation in the phantom was simulated by an explicit finite difference approximation of the bioheat equation (BHE). The temperature …distribution was then validated by a phantom heating experiment. The results showed that this antenna had a good heating ability and a wide heating area. A comparison between the calculation and the measurement showed a fair agreement in the temperature elevation. The validated model could be applied for the analysis of electromagnetic-temperature distribution in phantoms during the process of antenna design or thermotherapy experimentation. Show more

Keywords: Archimedean planar spiral antenna, finite-difference-Bioheat equation (FD-BHE) methods, microwave thermotherapy, phantom

DOI: 10.3233/THC-161195

Citation: Technology and Health Care, vol. 24, no. s2, pp. S675-S682, 2016

Authors: Sun, Zhishen | Liu, Guoqiang | Guo, Liang | Xia, Hui | Wang, Xinli

Article Type: Research Article

Abstract: BACKGROUND: As two of the new biological electrical impedance tomography (EIT), magneto-acoustic tomography (MAT) and magneto-acousto-electrical tomography (MAET) achieve both the high contrast property of EIT and the high spatial resolution property of sonography through combining EIT and sonography. As both MAT and MAET contain a uniform magnetic field, vibration and electrical current density, there is a secondary process both in MAT and in MAET, which is MAET and MAT respectively. OBJECTIVE: To analyze the effect of the secondary process on mass point vibration velocity (MPVV) propagation in MAT and MAET. METHODS: By …analyzing the total force to the sample, the wave equations of MPVV in MAT and MAET - when the secondary processes were considered - were derived. The expression of the attenuation constant in the wave number was derived in the case that the mass point vibration velocity propagates in the form of cylindrical wave and plane wave. Attenuations of propagation of the MPVV in several samples were quantified. RESULTS: Attenuations of the MPVV after propagating for 1 mm in copper or aluminum foil, and for 5 cm in gel phantom or biological soft tissue were less than 1%. CONCLUSION: Attenuations of the MPVV in MAT and MAET due to the secondary processes are relatively minor, and effects of the secondary processes on MPVV propagation in MAT and MAET can be ignored. Show more

Keywords: Magneto-acoustic tomography, magneto-acousto-electrical tomography, wave equation of mass point vibration velocity, linear damping

DOI: 10.3233/THC-161196

Citation: Technology and Health Care, vol. 24, no. s2, pp. S683-S689, 2016

Authors: Wu, Qian | Hu, Xiaoqing | Wen, Xiuyun | Li, Fuming | Fu, Wenbin

Article Type: Research Article

Abstract: OBJECTIVE: To study the safety and effectiveness of the Heart-Gallbladder acupuncture treatment for motor aphasia after stroke via clinical studies. METHODS: Sixty valid patients were divided into two groups randomly with a ratio of 1:1. The treatment group was the Heart-Gallbladder acupuncture group and the control group was the conventional acupuncture group. The two groups underwent testing before and after treatments, which included: the Aphasia Battery of Chinese (ABC), the Chinese functional communication profile (CFCP), and the Boston diagnostic aphasia examination (BDAE). RESULTS: All the BDAE, CFCP and ABC results showed …a significant difference between the two groups after treatment (P< 0.05), indicating that the Heart-Gallbladder acupuncture treatment for motor aphasia after stroke can reduce the degree of aphasia and improve patients' daily communication skills more than the conventional acupuncture treatment. The Heart-Gallbladder acupuncture treatment is better than the conventional acupuncture treatments for motor aphasia after stroke, with significantly improved scores for fluency, repetition, naming, and reading. CONCLUSIONS: Both the Heart-Gallbladder acupuncture and the conventional acupuncture are effective in the treatment of motor aphasia after stroke. Nevertheless, when compared to the conventional acupuncture, the Heart-Gallbladder acupuncture had better efficacy and it is safe as well. Show more

Keywords: Motor aphasia, stroke, Heart-Gallbladder treatment, tongue acupuncture

DOI: 10.3233/THC-161197

Citation: Technology and Health Care, vol. 24, no. s2, pp. S691-S696, 2016

Authors: Kim, Ji-Sun | Oh, Han-Byeol | Kim, A-Hee | Kim, Jun-Sik | Lee, Eun-Suk | Goh, Bong-Jun | Kim, Jae-Young | Jang, Kyungmin | Park, Jong-Rak | Chung, Soon-Cheol | Jun, Jae-Hoon

Article Type: Research Article

Abstract: BACKGROUND: Lasers are advantageous in some applications to stimulate a small target area and is used in various fields such as optogenetic, photoimmunological and neurophysiological studies. OBJECTIVE: This study aims to implement a non-contact sense of touch without damaging biological tissues using laser. METHODS: Various laser parameters were utilized in safety range to induce a sense of touch and investigate the human responses. With heat distribution simulation, the amount of changes in the temperature and the tendency in laser parameters of sensory stimulation were analyzed. RESULTS: The …results showed the identified tactile responses in safety range with various laser parameters and temperature distribution for the laser stimulus was obtained through the simulation. CONCLUSIONS: This study can be applied to the areas of sensory receptor stimulation, neurophysiology and clinical medicine. Show more

Keywords: Laser stimuli, pulse laser, perception, skin temperature simulation

DOI: 10.3233/THC-161198

Citation: Technology and Health Care, vol. 24, no. s2, pp. S697-S705, 2016

Authors: Li, Jiuwei | Pan, Bingyu | Jin, Tingting | Huang, Zhipei | Ye, Shiwei | Wu, Jiankang | Huang, Zhen | Xie, Bin | Luo, Chun | Wang, Cui

Article Type: Research Article

Abstract: BACKGROUND: Nowadays, stroke is a leading cause of disability in adults. Assessment of motor performance has played an important role in rehabilitation for post stroke patients. Therefore, it is quite important to develop an automatic assessment system of motor function. OBJECTIVE: The purpose of this study is to assess the performance of the single task upper-limb movements quantitatively among stroke survivors. METHODS: Eleven normal subjects and thirty-five subjects with stroke were involved in this study. The subjects, who were wearing the micro-sensor motion capture system, performed shoulder flexion in a sitting …position. The system recorded three-dimensional kinematics data of limb movements in quaternions. By extracting the significant features from these data, we built a linear model to acquire the functional assessment score (FAS). RESULTS: All of the kinematics features have a significant statistical difference (P < 0.05) between patients and healthy people, while the feature values have a high correlation with Fugl-Meyer (FM) scores (r > 0.5, p < 0.05), indicating that these features are able to reflect the level of motion impairment. Furthermore, most samples of the linear model locate in the confidence interval after regression, with the residual approaching a normal distribution. These results show that the FAS is capable of motor function assessment for stroke survivors. CONCLUSION: These findings represent an important step towards a system that can be utilized for precise single task motor evaluation after stroke, applicable to clinical research and as a tool for rehabilitation. Show more

Keywords: Stroke, rehabilitation, motor assessment, upper-limb, micro-sensor

DOI: 10.3233/THC-161199

Citation: Technology and Health Care, vol. 24, no. s2, pp. S707-S715, 2016

Authors: Liao, Y.L. | Chen, H.B. | Zhou, L.H. | Zhen, X.

Article Type: Research Article

Abstract: The purpose of this study is to design and fabricate an anthropopathic abdominal phantom for accuracy evaluation of deformable image registration (DIR) algorithms in adaptive radiation therapy. The constructed deformable organs, including the liver, kidney, spleen and stomach, are made of mixture of polyvinyl chloride (PVC) and softener dioctyl terephthalate, while the rigid structures, i.e. vertebrae, are made of white cement. Relation between the PVC-softener blending ratio and organ CT number is studied, and three-dimensional printing technic is employed to create highly anthropopathic organs in terms of organ shape and density. Detailed steps for phantom construction, landmark point placement …and choice of phantom ingredients and construction recipe are introduced. Preliminary results of the mechanical properties of the fabricated organs are also presented. The experimental results indicate that the constructed phantom has satisfactory elastic characteristics and close CT number with corporal organs, and can potentially be applied to simulate real abdominal organ deformation in geometric accuracy validation of DIR algorithms. Show more

Keywords: Three-dimensional deformable phantom, deformable image registration, PVC, phantom construction

DOI: 10.3233/THC-161200

Citation: Technology and Health Care, vol. 24, no. s2, pp. S717-S723, 2016

Authors: Niu, Renjie | Fu, Chenyu | Xu, Zhiyong | Huang, Jianyuan

Article Type: Research Article

Abstract: BACKGROUND: Doctors who practice Traditional Chinese Medicine (TCM) diagnose using four methods - inspection, auscultation and olfaction, interrogation, and pulse feeling/palpation. The shape and shape changes of the moon marks on the nails are an important indication when judging the patient's health. There are a series of classical and experimental theories about moon marks in TCM, which does not have support from statistical data. OBJECTIVE: To verify some experiential theories on moon mark in TCM by automatic data-processing equipment. METHODS: This paper proposes the equipment that utilizes image processing technology to …collect moon mark data of different target groups conveniently and quickly, building a database that combines this information with that gathered from the health and mental status questionnaire in each test. RESULTS: This equipment has a simple design, a low cost, and an optimized algorithm. The practice has been proven to quickly complete automatic acquisition and preservation of key data about moon marks. CONCLUSION: In the future, some conclusions will likely be obtained from these data; some changes of moon marks related to a special pathological change will be established with statistical methods. Show more

Keywords: Moon mark, Traditional Chinese Medicine, real time tracking

DOI: 10.3233/THC-161201

Citation: Technology and Health Care, vol. 24, no. s2, pp. S725-S732, 2016

Authors: Lv, Jingxiang | Liu, Guoqiang | Wang, Xinli | Xia, Hui

Article Type: Research Article

Abstract: Magneto-Acousto-Electrical Tomography (MAET) is a novel hybrid modality that can provide a high spatial resolution in determining the electrical conductivity of biological tissue. The present paper primarily analyzes the existing basic formulations with the MAET, derives the propagation equations of the sound wave when the mass density of the biological tissues are variable, and then solves the respective current density and potential difference in an inhomogeneous and homogeneous density medium based on the sound speeds obtained. Finally, numerical simulations are performed. As is shown, sound waves affect magneto-acousto-electrical tomography while varying the biological tissue mass density.

Keywords: Acoustic characteristic, forward problem, MAET, conductivity

DOI: 10.3233/THC-161202

Citation: Technology and Health Care, vol. 24, no. s2, pp. S733-S738, 2016

Authors: Zhang, Chao | Liu, Guoqiang | Li, Yanhong | Song, Xianjin

Article Type: Research Article

Abstract: BACKGROUND: Efficient mid-range wireless power transfer between transmitter and the receiver has been achieved based on the magnetic resonant coupling method. The influence of electromagnetic field on the human body due to resonant wireless power transfer system (RWPT) should be taken into account during the design process of the system. OBJECTIVE: To analyze the transfer performance of the RWPT system and the change rules of the specific absorption rate (SAR) in the human head model due to the RWPT system. METHODS: The circuit-field coupling method for a RWPT system with consideration of the …displacement current was presented. The relationship between the spiral coil parameters and transfer performance was studied. The SAR in the human head model was calculated under two different exposure conditions. RESULTS: A system with output power higher than 10 W at 0.2 m distance operating at a frequency of approximately 1 MHz was designed. The FEM simulation results show the peak SAR value is below the safety limit which appeared when the human head model is in front of the transmitter. CONCLUSION: The simulation results agreed well with the experimental results, which verified the validity of the analysis and design. Show more

Keywords: Wireless power transfer, SAR, resonant coupling, field-circuit coupling method, FEM

DOI: 10.3233/THC-161203

Citation: Technology and Health Care, vol. 24, no. s2, pp. S739-S746, 2016

Authors: Li, X. | Zhang, Y.Y. | Shi, Y.H. | Zhou, L.H. | Zhen, X.

Article Type: Research Article

Abstract: Deformable image registration (DIR) is a critical technic in adaptive radiotherapy (ART) to propagate contours between planning computerized tomography (CT) images and treatment CT/Cone-beam CT (CBCT) image to account for organ deformation for treatment re-planning. To validate the ability and accuracy of DIR algorithms in organ at risk (OAR) contours mapping, seven intensity-based DIR strategies are tested on the planning CT and weekly CBCT images from six Head & Neck cancer patients who underwent a 6 ∼ 7 weeks intensity-modulated radiation therapy (IMRT). Three similarity metrics, i.e. the Dice similarity coefficient (DSC), the percentage error (PE) and the Hausdorff distance …(HD), are employed to measure the agreement between the propagated contours and the physician delineated ground truths. It is found that the performance of all the evaluated DIR algorithms declines as the treatment proceeds. No statistically significant performance difference is observed between different DIR algorithms (p> 0.05), except for the double force demons (DFD) which yields the worst result in terms of DSC and PE. For the metric HD, all the DIR algorithms behaved unsatisfactorily with no statistically significant performance difference (p= 0.273). These findings suggested that special care should be taken when utilizing the intensity-based DIR algorithms involved in this study to deform OAR contours between CT and CBCT, especially for those organs with low contrast. Show more

Keywords: Adaptive radiotherapy, deformable image registration, CBCT, contour propagation, head & neck cancer

DOI: 10.3233/THC-161204

Citation: Technology and Health Care, vol. 24, no. s2, pp. S747-S755, 2016

Authors: Sun, Y.P. | Zhang, S. | Cui, Z. | Qu, L.L.

Article Type: Research Article

Abstract: Based on compressive sensing (CS) technology, a high resolution confocal microwave imaging algorithm is proposed for breast cancer detection. With the exploitation of the spatial sparsity of the target space, the proposed image reconstruction problem is cast within the framework of CS and solved by the sparse constraint optimization. The effectiveness and validity of the proposed CS imaging method is verified by the full wave synthetic data from numerical breast phantom using finite-difference time-domain (FDTD) method. The imaging results have shown that the proposed imaging scheme can improve the imaging quality while significantly reducing the amount of data measurements and …collection time when compared to the traditional delay-and-sum imaging algorithm. Show more

Keywords: Microwave imaging, breast cancer detection, compressive sensing (CS), FDTD method

DOI: 10.3233/THC-161205

Citation: Technology and Health Care, vol. 24, no. s2, pp. S757-S765, 2016

Authors: Ren, Fulong | Li, Wei | Yang, Jinzhu | Geng, Huan | Zhao, Dazhe

Article Type: Research Article

Abstract: BACKGROUND: Existing methods may fail to locate and segment the optic disc (OD) due to imprecise boundaries, inconsistent image contrast and deceptive edge features in retinal images. OBJECTIVE: To locate the OD and detect the OD boundary accurately. METHODS: The method exploits a multi-stage strategy in the detection procedure. Firstly, OD location candidate regions are identified based on high-intensity feature and vessels convergence property. Secondly, a line operator filter for circular brightness feature detection is designed to locate the OD accurately on candidates. Thirdly, an initialized contour is obtained by iterative thresholding and …ellipse fitting based on the detected OD position. Finally, a region-based active contour model in a variational level set formulation and ellipse fitting are employed to estimate the OD boundary. RESULTS: The proposed methodology achieves an accuracy of 98.67% for OD identification and a mean distance to the closest point of 2 pixels in detecting the OD boundary. CONCLUSION: The results illuminate that the proposed method is effective in the fast, automatic, and accurate localization and boundary detection of the OD. The present work contributes to the more effective evaluation of the OD and realizing automatic screening system for early eye diseases to a large extent. Show more

Keywords: Optic disc localization, optic disc segmentation, retinal images, level set method

DOI: 10.3233/THC-161206

Citation: Technology and Health Care, vol. 24, no. s2, pp. S767-S776, 2016

Authors: Lee, J.-S. | Lin, K.-W. | Syue, J.-L.

Article Type: Research Article

Abstract: Currently, cardiovascular disease affects a relatively high proportion of the world's population. Thus, developing simple and effective methods for monitoring patients with cardiovascular disease is critical for research. Monitoring the heart rate of patients is a relatively simple and effective method for managing patients with this condition. For patients, the desired heart rate monitoring equipment should be portable, instantaneous, and accurate. Because smartphones have become the most prevalent mobile device, we utilized this technology as a platform for developing a novel heart-rate measurement system. Catering to the phenomenon of people using the front camera of their smartphones as a mirror, …the proposed system was designed to analyze facial-image sequences captured using the front camera. A spatiotemporal alpha-trimmed mean filter was developed to estimate a user's heart rate quickly and accurately. The experimental results show that in addition to achieving these objectives, the developed system outperforms a similar personal computer-based system. In addition, the system performs effectively even when users are wearing glasses. Hence, the proposed system demonstrates practical value for people who must monitor their heart rate daily. Show more

Keywords: Smartphone, photoplethysmography (PPG), heart rate

DOI: 10.3233/THC-161207

Citation: Technology and Health Care, vol. 24, no. s2, pp. S777-S783, 2016

Authors: Feng, Yuan | Guo, Hao | Zhang, Hongmiao | Li, Chungang | Sun, Lining | Mutic, Sasa | Ji, Songbai | Hu, Yanle

Article Type: Research Article

Abstract: BACKGROUND: In recent years, MR images have been increasingly used in therapeutic applications such as image-guided radiotherapy (IGRT). However, images with low contrast values and noises present challenges for image segmentation. OBJECTIVE: The objective of this study is to develop a robust method based on fuzzy C-means (FCM) method which can segment MR images polluted with Gaussian noise. METHODS: A modified FCM algorithm accommodating non-local pixel information via Hausdorff distance was developed for segmenting MR images. The membership and objective functions were modified accordingly. Segmentations with different weights of the Hausdorff distance …were compared. RESULTS: Segmentation tests using synthetic and MR images showed that the proposed algorithm was better at resolving boundaries and more robust to Gaussian noise. By segmenting a sample MR image of a tumor, we further showed the capability of the method in capturing the centroid of the target region. CONCLUSIONS: The modified FCM algorithm with neighboring information can be used to segment blurry images with potential applications in segmenting motion MR images in image-guided radiotherapy (IGRT). Show more

Keywords: Segmentation, Hausdorff distance, fuzzy C-means, motion images, MR images

DOI: 10.3233/THC-161208

Citation: Technology and Health Care, vol. 24, no. s2, pp. S785-S793, 2016

Authors: Liang, Shuang | Choi, Kup-Sze | Qin, Jing | Wang, Qiong | Pang, Wai-Man | Heng, Pheng-Ann

Article Type: Research Article

Abstract: BACKGROUND: The effective connectivity refers explicitly to the influence that one neural system exerts over another in frequency domain. To investigate the propagation of neuronal activity in certain frequency can help us reveal the mechanisms of information processing by brain. OBJECTIVE: This study investigates the detection of effective connectivity and analyzes the complex brain network connection mode associated with motor imagery (MI) tasks. METHODS: The effective connectivity among the primary motor area is firstly explored using partial directed coherence (PDC) combined with multivariate empirical mode decomposition (MEMD) based on electroencephalography (EEG) …data. Then a new approach is proposed to analyze the connection mode of the complex brain network via the information flow pattern. RESULTS: Our results demonstrate that significant effective connectivity exists in the bilateral hemisphere during the tasks, regardless of the left-/right-hand MI tasks. Furthermore, the out-in rate results of the information flow reveal the existence of the contralateral lateralization. The classification performance of left-/right-hand MI tasks can be improved by careful selection of intrinsic mode functions (IMFs). CONCLUSION: The proposed method can provide efficient features for the detection of MI tasks and has great potential to be applied in brain computer interface (BCI). Show more

Keywords: Electroencephalogram (EEG), information flow pattern, multivariate empirical mode decomposition (MEMD), effective connectivity, motor imagery (MI)

DOI: 10.3233/THC-161212

Citation: Technology and Health Care, vol. 24, no. s2, pp. S795-S801, 2016

Authors: Stepanov, Rodion | Podtaev, Sergey | Dumler, Andrey | Chugainov, Sergey

Article Type: Research Article

Abstract: BACKGROUND: Impedance cardiography (ICG) is an inexpensive, noninvasive technique for estimating hemodynamic parameters. ICG can be used to obtain the ejection fraction of the left atrium and to monitor systolic time intervals. Traditional ICG technique does not enable unambiguous detection of the left ventricle ejection time (LVET) and the time relationships between specific marker points. OBJECTIVE: This work aims to approbate a new approach for ICG signal processing using wavelet transform (WT) and to investigate the possibilities of this approach for determination of the parameters which are related to the stroke volume (SV), in particular …LVET. METHODS: Thoracic tetrapolar polyrheocardiography method for simultaneous registration of ECG, ICG and phonocardiograms has been used. A control group consisted of eight healthy men aged 20-25 years. In addition, four patients with essential hypertension participated in the study. Wavelet representation of the ICG data produced local maxima in a two dimensional distribution of the wavelet coefficient. Each extremum point was characterized by the amplitude, scale and time, which determine SV. RESULTS: LVET was defined as the scale corresponding to the E-wave maximum related to the systolic phase of the cardiac cycle. Also, we defined the initial systolic time interval (ISTI) as the time interval between R peak in the ECG and E-wave maximum on the wavelet plane. During functional test LVET and ISTI values defined by WT demonstrated a proper hemodynamic response to loading for the control group and patients with essential hypertension. CONCLUSION: The proposed approach demonstrates the ability of ICG-WT technique for adequate assessment of SV parameters, including cardiac time intervals. Show more

Keywords: Impedance cardiography, wavelet transform, hemodynamic parameters

DOI: 10.3233/THC-161213

Citation: Technology and Health Care, vol. 24, no. s2, pp. S803-S809, 2016

Authors: Wang, Hao | Li, Xin-Yuan | An, Yan-Ming | Guo, Ya-Min

Article Type: Research Article

Abstract: BACKGROUND: Surgical site infection is one of the most common complications of conventional laparoscopic surgery. Preventing infection of the incision is particularly important. OBJECTIVE: To discuss how to prevent the occurrence of surgical site infection after contaminated abdominal surgery. METHODS: Five hundred and fifty-one surgery patients with ``contaminated abdominal incisions'' from January 2011 to May 2013 were analyzed in terms of the preventative treatment, and summarized for surgical site infection. Subcutaneous tissue flushed with normal saline + hydrogen peroxide before suturing in the intervention 1 group; subcutaneous tissue flushed with normal saline + …0.5% povidone-iodine before suturing in the intervention 2 group. RESULTS: When subcutaneous fat was contaminated to a depth of ≤ 2.5 cm, the rates of surgical site infection in the control group and the intervention groups showed no significant difference (P > 0.05). When subcutaneous fat was contaminated to a depth of ≥ 3.0 cm, the rate of surgical site infection in the control group compared with the intervention one group was not statistically different (P > 0.05). The rate of surgical site infection in the control group compared with the intervention two group was statistical significant (P < 0.05). The rate of surgical site infection in the intervention one group compared with the intervention two group was statistical significant (P < 0.05). CONCLUSIONS: Preoperative control of the blood sugar; correction of anemia and the hypoalbuminemia; use of intraoperative the high-frequency electrotome; irrigation of the incision with plenty of physiological saline +$ iodophor before suturing the subcutaneous fat layer were key to effectively preventing infection in contaminated abdominal incisions. Show more

Keywords: Surgical site infection, preventive treatment

DOI: 10.3233/THC-161209

Citation: Technology and Health Care, vol. 24, no. s2, pp. S811-S815, 2016

Authors: Zou, Ling | Guo, Qian | Xu, Yi | Yang, Biao | Jiao, Zhuqing | Xiang, Jianbo

Article Type: Research Article

Abstract: Functional magnetic resonance imaging (fMRI) is an important tool in neuroscience for assessing connectivity and interactions between distant areas of the brain. To find and characterize the coherent patterns of brain activity as a means of identifying brain systems for the cognitive reappraisal of the emotion task, both density-based k-means clustering and independent component analysis (ICA) methods can be applied to characterize the interactions between brain regions involved in cognitive reappraisal of emotion. Our results reveal that compared with the ICA method, the density-based k-means clustering method provides a higher sensitivity of polymerization. In addition, it is more sensitive to …those relatively weak functional connection regions. Thus, the study concludes that in the process of receiving emotional stimuli, the relatively obvious activation areas are mainly distributed in the frontal lobe, cingulum and near the hypothalamus. Furthermore, density-based k-means clustering method creates a more reliable method for follow-up studies of brain functional connectivity. Show more

Keywords: Functional connectivity, cognitive reappraisal, density-based k-means clustering method, ICA

DOI: 10.3233/THC-161210

Citation: Technology and Health Care, vol. 24, no. s2, pp. S817-S825, 2016

Authors: Wang, Heng | Wu, Jianan | Zhuo, Zihan | Tang, Jintian

Article Type: Research Article

Abstract: In order to ensure the safety and effectiveness of magnetic induction hyperthermia in clinical applications, numerical simulations on the temperature distributions and extent of thermal damage to the targeted regions must be conducted in the preoperative treatment planning system. In this paper, three models, including a thermoseed thermogenesis model, tissue heat transfer model, and tissue thermal damage model, were established based on the four-dimensional energy field, temperature field, and thermal damage field distributions exhibited during hyperthermia. In addition, a numerical simulation study was conducted using the Finite Volume Method (FVM), and the accuracy and reliability of the magnetic induction hyperthermia …model and its numerical calculations were verified using computer simulations and experimental results. Thus, this study promoted the application of computing methods to magnetic induction therapy and conformal hyperthermia, and improved the accuracy of the temperature field and tissue thermal damage distribution predictions. Show more

Keywords: Magnetic induction hyperthermia, numerical simulation, tissue thermal damage, FVM

DOI: 10.3233/THC-161211

Citation: Technology and Health Care, vol. 24, no. s2, pp. S827-S839, 2016

Authors: El-Latif Hesham, Abd | Alrumman, Sulaiman A.

Article Type: Research Article

Abstract: BACKGROUND: Despite medical progress worldwide, dental caries are still widespread. Miswak is derived from the plant Arak (Salvadora persica). It is used by Muslim peoples as a natural product for the cleansing of teeth, to ensure oral and dental hygiene. OBJECTIVE: This study was conducted to evaluate the antimicrobial effects of ethanol, methanol, and ethanol/methanol extracts of Miswak against three bacterial pathogens of the oral cavity. METHODS: The pathogens were isolated from the oral cavity of volunteers/patients and were identified on the basis of 16S rRNA gene amplification data. Sequence comparisons …were made with 16S rRNA gene sequences available in the GenBank database. RESULTS: The results of sequence alignment and phylogenetic analysis identified the three pathogens as being Staphylococcus aureus strain KKU-020, Enterococcus faecalis strain KKU-021 and Klebsiella pneumoniae strain KKU-022. All Miswak extracts showed powerful antimicrobial activity against the three pathogens. The maximum zone of inhibition (40.67 ± 0.88 mm) was observed against E. faecalis KKU-021 with ethanolic extracts whilst methanolic extracts showed the minimum zone of inhibition (10.33 ± 0.88 mm) against K. pneumonia KKU-022. CONCLUSION: Based upon the significant effects of the Miswak extracts, against the oral cavity pathogens in our study, we recommend that Miswak could be used as a dental hygiene method to prevent tooth caries. Show more

Keywords: Salvadora persica, Miswak, antibacterial activities, oral cavity pathogens, 16S rRNA gene sequences, phylogenetic analysis

DOI: 10.3233/THC-161214

Citation: Technology and Health Care, vol. 24, no. s2, pp. S841-S848, 2016

Authors: Zang, Xizhe | Liu, Xinyu | Zhu, Yanhe | Zhao, Jie

Article Type: Research Article

Abstract: BACKGROUND: The study of human walking patterns mainly focuses on how control affects walking because control schemes are considered to be dominant in human walking. OBJECTIVE: This study proposes that not only fine control schemes but also optimized body segment parameters are responsible for humans' low-energy walking. METHODS: A passive dynamic walker provides the possibility of analyzing the effect of parameters on walking efficiency because of its ability to walk without any control. Thus, a passive dynamic walking model with a relatively human-like structure was built, and a parameter optimization process based on …the gait sensitivity norm was implemented to determine the optimal mechanical parameters by numerical simulation. RESULTS: The results were close to human body parameters, thus indicating that humans can walk under a passive pattern based on their body segment parameters. A quasi-passive walking prototype was built on the basis of the optimization results. Experiments showed that a passive robot with optimized parameters could walk on level ground with only a simple hip actuation. CONCLUSION: This result implies that humans can walk under a passive pattern based on their body segment parameters with only simple control strategy implying that humans can opt to walk instinctively under a passive pattern. Show more

Keywords: Human walking, passive dynamic walking, parameters optimization, energy consumption

DOI: 10.3233/THC-161215

Citation: Technology and Health Care, vol. 24, no. s2, pp. S849-S858, 2016