Technology and Health Care - Volume 25, issue S1

Authors: Shin, Sun Hye | Kang, Seung Rok | Kwon, Tae-Kyu | Yu, Changho

Article Type: Research Article

Abstract: BACKGROUND: Lower back pain has a lifetime prevalence of 80% for people in a modern society, and in recent years, spinal stabilization movement has been highlighted as a method to treat lower back pain and an unbalanced position. OBJECTIVE: The objectives of this study were to assess the trunk muscle activities in accordance with the tilt angles (10 ∘ , 20 ∘ , 30 ∘ , 40 ∘ ) during trunk tilt exercises with a 3D dynamic exercise device. METHODS: Active …tilt mode (a self-generated active movement in the angle and direction steered by the user) was used in this study. The rotation capability enabled the investigation of the anterior (A), anterior right (AR), right (R), posterior right (PR), posterior (P), posterior left (PL), left (L), and anterior left (AL) tilt directions. EMG signals of the trunk (3 global muscles: rectus abdominis, RA, external obliques, EO, latissimus dorsi, LD, and 1 local muscle: multifidus, MF) muscles were obtained. RESULTS: The MF muscle activity was higher while the anterior tilt was maintained, and the abdominal muscle activity was higher while the posterior tilt was maintained. Also, as the tilt angle increased, the activity of the muscles opposite the tilt direction increased. CONCLUSIONS: The results indicate that to maintain equilibrium through posture stabilization during whole body tilting, the human body maintains a proper interaction among the body segments as well as between the body and the execution environment. Moreover, stability is maintained through the co-contraction of antagonistic and agonistic muscles. In future studies, it will be important to conduct research on improving imbalance in the trunk muscles. Show more

Keywords: Trunk stabilization exercise, whole body tilt, tilt angle, EMG

DOI: 10.3233/THC-171308

Citation: Technology and Health Care, vol. 25, no. S1, pp. 73-81, 2017

Authors: Kim, Jong Hoon | Lee, Jyung Hyun | Cho, Jin-Ho

Article Type: Research Article

Abstract: BACKGOUND: The hearing impaired population has been increasing; many people suffer from hearing problems. To deal with this difficulty, various types of hearing aids are being rapidly developed. In particular, fully implantable hearing aids are being actively studied to improve the performance of existing hearing aids and to reduce the stigma of hearing loss patients. It has to be of small size and low-power consumption for easy implantation and long-term use. OBJECTIVE: The objective of the study was to implement a small size and low-power consumption successive approximation register analog-to-digital converter (SAR ADC) for fully implantable …hearing aids. METHODS: The ADC was selected as the SAR ADC because its analog circuit components are less required by the feedback circuit of the SAR ADC than the sigma-delta ADC which is conventionally used in hearing aids, and it has advantages in the area and power consumption. So, the circuit of SAR ADC is designed considering the speech region of humans because the objective is to deliver the speech signals of humans to hearing loss patients. If the switch of sample and hold works in the on/off positions, the charge injection and clock feedthrough are produced by a parasitic capacitor. These problems affect the linearity of the hold voltage, and as a result, an error of the bit conversion is generated. In order to solve the problem, a CMOS switch that consists of NMOS and PMOS was used, and it reduces the charge injection because the charge carriers in the NMOS and PMOS have inversed polarity. So, 16 bit conversion is performed before the occurrence of the Least Significant Bit (LSB) error. In order to minimize the offset voltage and power consumption of the designed comparator, we designed a preamplifier with current mirror. Therefore, the power consumption was reduced by the power control switch used in the comparator. RESULTS: The layout of the designed SAR ADC was performed by Virtuoso Layout Editor (Cadence, USA). In the layout result, the size of the designed SAR ADC occupied 124.9 μ m × 152.1 μ m. The circuit verification was performed by layout versus schematic (LVS) and design rule check (DRC) which are provided by Calibre (Mentor Graphics, USA), and it was confirmed that there was no error. The designed SAR ADC was implemented in SMIC 180 nm CMOS technology. The operation of the manufactured SAR ADC was confirmed by using an oscilloscope. The SAR ADC output was measured using a distortion meter (HM 8027), when applying pure tone sounds of 94 dB SPL at 500, 800, and 1600 Hz regions. As a result, the THD performance of the proposed chip was satisfied with the ANSI. s3. 22. 2003 standard. CONCLUSIONS: We proposed a low-power 16-bit 32 kHz SAR ADC for fully implantable hearing aids. The manufactured SAR ADC based on this design was confirmed to have advantages in power consumption and size through the comparison with the conventional ADC. Therefore, the manufactured SAR ADC is expected to be used in the implantable medical device field and speech signal processing field, which require small size and low power consumption. Show more

Keywords: Fully implantable hearing aids, SAR ADC, integrated circuit

DOI: 10.3233/THC-171309

Citation: Technology and Health Care, vol. 25, no. S1, pp. 83-92, 2017

Authors: Kim, Ha Yeon | Kim, Eun Joo | You, Joshua (Sung) H.

Article Type: Research Article

Abstract: BACKGROUND: An improved understanding of the mechanisms underlying locomotor networks has the potential to benefit the neurorehabilitation of patients with neurological locomotor deficits. However, the specific locomotor networks that mediate adaptive locomotor performance and changes in gait speed remain unknown. OBJECTIVE: The aim of the present study was to examine patterns of cortical activation associated with the walking speeds of 1.5, 2.0, 2.5, and 3.0 km/h on a treadmill. METHODS: Functional near-infrared spectroscopy (fNIRS) was performed on a 30-year-old right-handed healthy female subject, and cerebral hemodynamic changes were observed in cortical locomotor network …areas including the primary sensorimotor cortex (SMC), premotor cortex (PMC), supplementary motor area (SMA), prefrontal cortex (PFC), and sensory association cortex (SAC). The software package NIRS-statistical parametric mapping (NIRS-SPM) was utilized to analyze fNIRS data in the MATLAB environment. SPM t-statistic maps were computed at an uncorrected threshold of p < 0.00001. RESULTS: At faster walking speeds, oxygenated hemoglobin (OxyHb) was concentrated in the PFC and indicated globalized locomotor network activation of the SMC, PMC, SMA, and PMC; additionally, the site with the highest cortical activation ratio shifted from the SMC to the SMA. CONCLUSIONS: Global locomotor network recruitment, in particular PFC activation indicated by OxyHb in our study, may indicate a response to increased cognitive-locomotor demand due to simultaneous postural maintenance and leg movement coordination. Show more

Keywords: Functional near-infrared spectroscopy, gait speed, neuroimaging signal processing

DOI: 10.3233/THC-171310

Citation: Technology and Health Care, vol. 25, no. S1, pp. 93-98, 2017

Authors: Yoon, Hyun S. | You, Joshua (Sung) H.

Article Type: Research Article

Abstract: BACKGROUND: Postural core instability is associated with poor dynamic balance and a high risk of serious falls. Both neurodevelopmental treatment (NDT) and dynamic neuromuscular stabilization (DNS) core stabilization exercises have been used to improve core stability, but the outcomes of these treatments remain unclear. OBJECTIVE: This study was undertaken to examine the therapeutic effects of NDT and DNS core stabilization exercises on muscular activity, core stability, and core muscle thickness. METHODS: Ten participants (5 healthy adults; 5 hemiparetic stroke patients) were recruited. Surface electromyography (EMG) was used to determine core muscle activity of …the transversus abdominis/internal oblique (TrA/IO), external oblique (EO), and rectus abdominis (RA) muscles. Ultrasound imaging was used to measure transversus abdominals/internal oblique (TrA/IO) thickness, and a pressure biofeedback unit (PBU) was used to measure core stability during the DNS and NDT core exercise conditions. Data are reported as median and range and were compared using nonparametric Mann – Whitney U test and Wilcoxon signed rank test at p < 0.05. RESULTS: Both healthy and hemiparetic stroke groups showed greater median EMG amplitude in the TrA/IO muscles, core stability, and muscle thickness values during the DNS exercise condition than during the NDT core exercise condition, respectively (p < 0.05). However, the relative changes in the EMG amplitude, core stability, and muscle thickness values were greater during the DNS exercise condition than during the NDT core exercise condition in the hemiparetic stroke patient group (p < 0.05). CONCLUSIONS: Our novel results provide the first clinical evidence that DNS is more effective than NDT in both healthy and hemiparetic stroke subjects to provide superior deep core muscle activation, core stabilization, and muscle thickness. Moreover, such advantageous therapeutic benefits of the DNS core stabilization exercise over the NDT exercise were more apparent in the hemiparetis stroke patients than normal controls. Show more

Keywords: Electromyography signal processing, ultrasound imaging, dynamic neuromuscular stabilization

DOI: 10.3233/THC-171311

Citation: Technology and Health Care, vol. 25, no. S1, pp. 99-106, 2017

Authors: Liao, Xiongfei | Lang, Jinyi | Li, Ningshan | Wang, Pei | Li, Jie | Yang, Jack | Chen, Yazheng

Article Type: Research Article

Abstract: The goal of this study was to evaluate the use of multi-criteria optimization (MCO) in the planning and optimization of intensity-modulated radiotherapy (IMRT). Twenty (20) IMRT patients (ten (10) with prostate cancer and ten (10) with lung cancer) were randomly selected. The treatment plans for these patients were designed using direct machine parameter optimization (DMPO). Based on these plans, new plans were designed using multi-criteria optimization (MCO), keeping the optimization objectives and constraints unchanged. Comparisons were made between the new plans, which were based on MCO and DMPO, including the dose distribution, dose volume histogram (DVH), the optimization time and …the number of monitor units (MUs). The plan designed using both optimization approaches satisfied all clinical requirements. For similar or better target coverage, the rectum, bladder and small bowel were better protected using MCO than when using DMPO. Additionally, MCO reduced the time for optimization by 58% on average, whereas the MUs increased the time for optimization by 32% on average for prostate cancer. For lung cancer cases, the entire lung, heart and spinal cord were better protected using MCO compared to DMPO. Similarly, MCO reduced the time for optimization by 59% on average, whereas the MUs increased the time for optimization by 11% on average. Compared to DMPO, MCO reduces the dose of the organs at risk (OAR) and shortens the time required for optimization. Show more

Keywords: Multi-criteria optimization (MCO), IMRT, direct machine parameter optimization (DMPO), Pareto optimization

DOI: 10.3233/THC-171312

Citation: Technology and Health Care, vol. 25, no. S1, pp. 107-114, 2017

Authors: Kang, Seung Rok | Min, Jin-Young | Yu, Changho | Kwon, Tae-Kyu

Article Type: Research Article

Abstract: OBJECTIVE: In this paper, we investigated the recovery of the lactate level, muscular fatigue, and heart rate recovery (HRR) with respect to whole body vibration (WBV) during the rest stage after a gait exercise. METHODS: A total of 24 healthy subjects with no medical history of exercise injury participated. The participants were divided into a training group with vibration during rest and a control group with the same conditions but without vibration. The subjects performed a gait exercise with a slope of 15% and velocity of 4 km/h to consume 450 kcal in 30 min. Then, …they rested on a vibrating chair or on a chair without vibrations for 30 min. The vibration protocol consists of a frequency of 10 Hz and amplitude of 5 mm. To estimate the recovery effect, we measured the lactate levels in blood, spectral edge frequency (SEF) of MVIC, and HRR before, immediately after exercise, and after rest. RESULTS: The results showed that the lactate level in the training group decreased more (93.8%) than in the control group (32.8%). Also, HRR showed a similar trend with a recovery of 88.39% in the training group but 64.72% in the control group. We considered that whole-body vibrations during rest would help remove lactic acid by improving the level of lactic acid oxidation with stimulated blood vessels in the muscles and by helping to maintain blood flow. Also, WBV would lead to compensation to actively decrease the fast excess post-exercise oxygen consumption from blood circulation. CONCLUSIONS: We suggest that whole-body vibrations during rest can provide fast, efficient fatigue recovery as a cool down exercise for women, the elderly, and patients without other activity after intense exercise. Show more

Keywords: Fatigue, lactate level in blood, heart rate recovery, whole body vibration, healthcare

DOI: 10.3233/THC-171313

Citation: Technology and Health Care, vol. 25, no. S1, pp. 115-123, 2017

Authors: Qiao, Aike | Song, Xiaorui | Peng, Kun | Du, Guowei | Li, Gaoyang | Chen, Zhihui

Article Type: Research Article

Abstract: BACKGROUND: The high risk of hypertension in middle-aged and elderly people has led to the development of the cardio-ankle vascular index (CAVI), a novel predictor of cardiovascular events. OBJECTIVE: This paper aimed to determine how reliably hypertension can be diagnosed in middle-aged and elderly people by measuring CAVI. METHODS: One hundred and ninety-five subjects (69 males/126 females; mean age of 56.06 ± 2.08 years) were enrolled. CAVI were measured using a blood pressure and pulse monitor device. RESULTS: The CAVI was positively correlated with age, SBP, PP …and PPI in the hypertension group (r = 0.656, 0.388, 0.445, 0.376; all P < 0.05). The mean CAVI was the significant difference between each age group. The ROC results showed that the best diagnostic point was 8.350, where the sensitivity was 72.2% and the specificity was 72.3%. The positive rate of the CAVI was higher than normal blood pressure for those over 60 years of age. CONCLUSION: Compared with normal blood pressure measurements, CAVI measurements are relatively reliable for predicting hypertension in those over the age of 60. More attention should be paid to the CAVI ⩾ 8.350, which may be regarded as a simple and noninvasive reference index of hypertension diagnosis for middle-aged and elderly. Show more

Keywords: Hypertension, cardio-ankle vascular index, cardiovascular diseases; middle-aged and elderly, diagnosis validity

DOI: 10.3233/THC-171314

Citation: Technology and Health Care, vol. 25, no. S1, pp. 125-134, 2017

Authors: Li, Yan | Dai, Yongliang | Deng, Lei | Yu, Nan | Guo, Youmin

Article Type: Research Article

Abstract: BACKGROUND: There are few quantitative studies that directly evaluate methods of determining pulmonary embolism (PE). New computer-aided detection (CAD) methods for measuring PE may help in defining the relationship of PE to right heart failure (RHF). OBJECTIVES: We used CAD to investigate the severity of PE and explored whether the severity of PE was associated with RHF. METHODS: A fully automatic calculation conducted by CAD was made of the embolism area/lumen area, which was used to evaluate the severity of the PE. The vascular obstruction index (VOI) was also used to evaluate PE, …using the Mastora and Qanadli scores. Paired t tests were used to compare the severity of PE evaluated by Mastora or Qanadli score, to the severity determined by CAD. Correlation between the severity of the PE and RHF was also evaluated by Spearman’s rank correlation analysis. RESULTS: There was no significant difference between the PE evaluated by Mastora compared with the measurement by CAD (P = 0.720), and also no difference between evaluation by Qanadli and automatic measurement by CAD (P = 0.617). The severity of PE evaluated by Mastora, Qanadli, and CAD had significant positive correlation with RHF (R = 0.75 P = 0.01, R = 0.69 P = 0.02, R = 0.80 P = 0.00). CONCLUSION: We found strong correlation between RHF and the severity of PE evaluated by CAD, and the method was found to be simple and reliable. Show more

Keywords: Pulmonary embolism, mastora, qanadli, computer-aided detection

DOI: 10.3233/THC-171315

Citation: Technology and Health Care, vol. 25, no. S1, pp. 135-142, 2017

Authors: Yu, Zhifeng | Zhang, Haifang | Fu, Linjie | Lu, Xiaozuo

Article Type: Research Article

Abstract: BACKGROUND: Tongue observation often depends on subjective judgment, it is necessary to establish an objective and quantifiable standard for tongue observation. OBJECTIVE: To discuss the features of tongue manifestation of patients who suffered from eczema with different types and to reveal the clinical significance of the tongue images. METHODS: Two hundred patients with eczema were recruited and divided into three groups according to the diagnostic criteria. Acute group had 47 patients, subacute group had 82 patients, and chronic group had 71 patients. The computerized tongue image digital analysis device was used to detect …tongue parameters. The L * a * b * color model was applied to classify tongue parameters quantitatively. RESULTS: For parameters such as tongue color, tongue shape, color of tongue coating, and thickness or thinness of tongue coating, there was a significant difference among acute group, subacute group and chronic group (P < 0.05). For Lab values of both tongue and tongue coating, there was statistical significance among the above types of eczema (P < 0.05). CONCLUSIONS: Tongue images can reflect some features of eczema, and different types of eczema may be related to the changes of tongue images. The computerized tongue image digital analysis device can reflect the tongue characteristics of patients with eczema objectively. Show more

Keywords: Tongue manifestation, computerized tongue image digital analysis device, eczema, objective research

DOI: 10.3233/THC-171316

Citation: Technology and Health Care, vol. 25, no. S1, pp. 143-149, 2017

Authors: Liu, Chunxiu | Cai, Haoyuan | Jia, Jian | Cao, Tianyang | Xu, Chenghua | Liu, Chang

Article Type: Research Article

Abstract: BACKGROUND: C-reactive protein (CRP) is used to evaluate the evolution of infections and sepsis in critically ill patients. For POCT testing, biosensor-based detection techniques offer quick and convenient application. OBJECTIVE: A prototype three dimensional chip was fabricated based on a new optomagnetic method to achieve the rapid detection of CRP. METHODS: This work investigates a new technology for the quick quantitative detection of the C-reactive protein (CRP) by total internal reflection magnetic imaging (TIRMI) on a three dimensional optomagnetic sensor. Transparent glass and hydrophilic plastic film with channels were used to construct the …three dimensional sensor. The magnetic nanoparticles and immunological reagent were immobilized on the reaction area of the sensor. Samples were detected using total internal reflection magnetic spot imaging (TIRMI) based on a sandwich magnetic immunoassay by one-step assay. RESULTS: The developed 3D biosensor-TIRMI method showed a wide dynamic linear range (0.2–200 ng/ml) and quick detection (5 min) with low-sample volume (10 μ L). CONCLUSIONS: We have presented a three dimensional optical protein chip that fulfills the demanding for point-of-care diagnostics in terms of ease-of-use (one step assay), miniaturization, assay time. This approach shows great promise for application in clinical investigations of biological samples. Show more

Keywords: C-reactive protein, 3D optomagnetic sensor, total internal reflection magnetic imaging, all in one-step assay

DOI: 10.3233/THC-171317

Citation: Technology and Health Care, vol. 25, no. S1, pp. 151-156, 2017