• Journal of the Institute of Convergence Signal Processing
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• v.15 no.2
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• pp.64-69
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• 2014

Ultrasound system is one of the complex wireless signal processing systems that are widely used in the fields of modern industry such as medical diagnostics, underwater communications, and sensor-networks. Miniaturization of ultrasound system has been raging recently. In this paper, a hybrid LNA that is suitable for miniaturization and mobile diagnostic ultrasound system has been developed. The proposed LNA has low noise figure of less than 5dB, and the feedback resistor is designed to be electrically adjusted in order to attain the impedance-matching for various ultrasound transducers. It supports the whole ultrasound frequencies from 10KHz to 150MHz frequency band and also provides sleep modes. A gain from -18.8 to -29.5 dB is achieved by adjusting each transducer to fit the system character. Power consumption can be reduced up to 90% in similar performance as compared to the existing LNA.

• Journal of Biomedical Engineering Research
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• v.19 no.2
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• pp.171-176
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• 1998

The objective of this study was to re-evaluate ultrasound attenuation as an indicator of bone properties. Ultrasound attenuation(BUA), were measured in the three orthogonal directions of trabecular bone cubes, Measurements of bone mineral density(BMD) were made using quantitative computed tomography and apparent density by weighing bone specimens and measuring their volume. Ultrasonic modulus was calculated from the standard equation with apparent density and ultrasound velocity. Ultrasound attenuation at a frequency of 0.5 MHz and BUA were correlated with BMD and ultrasonic modulus in the anterior/posterior, medial/lateral, and superior/inferior directions. Analysis of correlations demonstrated that attenuation at 0.5 MHz was superior to BUA in describing both BMD and elastic modulus of trabecular bone. This result may be used to improve current ultrasound diagnostic techniques for assessing bone status.

• The Journal of the Acoustical Society of Korea
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• v.36 no.3
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• pp.172-178
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• 2017

Ultrasound has been widely used for biological and medical applications including induction of cell death, but a precise mechanism of induced cell death by ultrasound is controversial. In this study, an irradiation system with 40 kHz ultrasound was developed for a suitable cell death test of a representative unicellular organism, yeast, and used to study the biological effect of ultrasound on inducing cell death. Potassium Iodide (KI) dosimetry was used to devise an optimal system that successfully delivers 40 kHz ultrasound and produces reactive oxygen species in a 1.5 ml Eppendorf tube. Cell death was observed in an ultrasound transmission time-dependent fashion in this system. Thermal effect during irradiation was not observable in ultrasound induced cell death. Co-treatment of 40 kHz ultrasound and hydrogen peroxide showed a synergistic effect in inducing cell death. This finding suggests that 40 kHz ultrasound is related to reactive oxygen species formation. However, NAC (N-acetyl-L-cysteine) oxygen scavenger slightly inhibited the cell death by 40 kHz ultrasound. It was also found that 40 kHz ultrasound induced cell death was slightly inhibited by inhibitors of necrosis or apoptosis (glycyrrhizin or zVAD-fmk). This study suggests that cell death induced by 40 kHz ultrasound may not be exclusively related to reactive oxygen species formation and thermal effects in irradiated yeast cells.

• The Korean Journal of Pain
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• v.28 no.2
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• pp.122-128
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• 2015

Background: Caudal epidural injections have been commonly performed in patients with low back pain and radiculopathy. Although caudal injection has generally been accepted as a safe procedure, serious complications such as inadvertent intravascular injection and dural puncture can occur. The present prospective study was designed to investigate the influence of the depth of the inserted needle on the success rate of caudal epidural blocks. Methods: A total of 49 adults scheduled to receive caudal epidural injections were randomly divided into 2 groups: Group 1 to receive the caudal injection through a conventional method, i.e., caudal injection after advancement of the needle 1 cm into the sacral canal (n = 25), and Group 2 to receive the injection through a new method, i.e., injection right after penetrating the sacrococcygeal ligament (n = 24). Ultrasound was used to identify the sacral hiatus and to achieve accurate needle placement according to the allocated groups. Contrast dyed fluoroscopy was obtained to evaluate the epidural spread of injected materials and to monitor the possible complications. Results: The success rates of the caudal injections were 68.0% in Group 1 and 95.8% in Group 2 (P = 0.023). The incidences of intravascular injections were 24.0% in Group 1 and 0% in Group 2 (P = 0.022). No intrathecal injection was found in either of the two groups. Conclusions: The new caudal epidural injection technique tested in this study is a reliable alternative, with a higher success rate and lower risk of accidental intravascular injection than the conventional technique.

• Journal of Applied Reliability
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• v.15 no.1
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• pp.27-32
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• 2015

Functional safety is part of the overall safety relating to the equipment under control (EUC) and the EUC control system that depends on the correct functioning of the electrical/electronic/programmable electronic (E/E/PE) safety-related systems. Since the complexity of the medical equipment is increased, manufactures have to obtain functional safety as well as basic safety. This study proposes a perspective for applying functional safety to medical equipment. The research is carried out with respect to overall safety life-cycle of functional safety and essential performance of the medical equipment. The relationship between functional safety and essential performance is identified centered on the safety function. The essential performance using E/E/PE systems is defined as a safety function of functional safety. This approach is applied to a ultrasound imaging system as a case study.

• Journal of Acupuncture Research
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• v.35 no.1
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• pp.4-10
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• 2018

The aim of this report was to show the effects of acupotomy in patients with carpal tunnel syndrome. Four patients were treated with acupotomy twice. Visual analogue scale (VAS), Tinel's sign, Phalen's test, Boston carpal tunnel syndrome questionnaire (BCTQ), muscular strength test, and a cross-sectional area of median nerve was measured using ultrasound before and after treatment. In all 4 cases, the VAS score, BCTQ score and cross-sectional area of median nerve, all decreased and muscular strength test score increased. Tinel's sign and the Phalen's test changed from a positive to a negative in most cases. This report shows that acupotomy is an effective treatment for carpal tunnel syndrome. Further larger are needed to fully evaluate the beneficial effects of this treatment.

• Imaging Science in Dentistry
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• v.42 no.2
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• pp.115-119
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• 2012

Today, ultrasound imaging is being widely used to assess soft tissue lesions in the maxillofacial region. However, ultrasound investigations of intra-osseous lesions are rare, especially for tumors of the jaws. This report emphasized the capability of this useful imaging modality in identification of the characteristics of malignant conditions involving the bone. Mesenchymal chondrosarcoama, one of the unusual malignant conditions of the jaw, was presented in a young male with significant facial swelling. Different imaging modalities parallel with the histopathologic investigation confirmed the diagnosis. Interestingly, destruction of the bony cortex and new bone formation with a characteristic "sun ray appearance", highly suggestive of sarcomas, was manifested on the ultrasonograph. Thus, this report presented the ultrasonographic features of chondrosarcoma of mandible and considered the ultrasonography to be a useful imaging modality to evaluate intra-osseous jaw lesions.

• Journal of Pharmacopuncture
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• v.14 no.1
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• pp.87-95
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• 2011

Purpose : In order to estimate clinical effects of Oriental Medicine Treatment with acupotomy therapy of Peroneal nerve Palsy. Methods : From 10th June, 2010 to 19th June, 2010, 1 female patient diagnosed as Peroneal nerve Palsy(clinical diagnosed) was treated with general oriental medicine therapy (acupuncture, pharmacopuncture, moxibustion, cupping, physical therapy, herbal medication) and acupotomy. Results : The patient's left foot drop was remarkably improved. Conclusions : This study demonstrates that oriental medical treatment with acuputomy therapy has notable effect in improving symptoms of peroneal nerve palsy. as though we had not wide experience in this treatment, more research is needed.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.21
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• pp.9101-9105
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• 2014

Background: The purpose of this study was to compare the accuracy and effectiveness of automated breast volume scanning (ABVS) and hand-held ultrasound (HHUS) in the detection of breast cancer in a large population group with a long-term follow-up, and to investigate whether different ultrasound systems may influence the estimation of cancer detection. Materials and Methods: Institutional review board approval was obtained for this retrospective study, and informed consent was waived. From September 2010 to August 2011, a total of 1,866 ABVS and 3,700 HHUS participants, who underwent these procedures at our institute, were included in this study. Cancers occurring during the study and subsequent follow-up were evaluated. The reference standard was a combination of histology and follow-up imaging (${\geq}12months$). The recall rate, cancer detection yield, diagnostic accuracy, sensitivity, specificity, and positive (PPV) and negative (NPV) predictive values were calculated with exact 95% confidence intervals. Results: The recall rate was 2.57 per 1,000 (48/1,866) for ABVS and 3.57 per 1,000 (132/3,700) for HHUS, with a significant difference (p=0.048). The cancer detection yield was 3.8 per 1,000 for ABVS and 2.7 per 1,000 for HHUS. The diagnostic accuracy was 97.7% for ABVS and 96.5% for HHUS with statistical significance (p=0.018). The specificity of ABVS and HHUS were 97.8%, 96.7%, respectively (p=0.022). Conclusions: ABVS shows a comparable diagnostic performance to HHUS. ABVS is an effective supplemental tool for mammography in breast cancer detection in a large population.

• Journal of Biomedical Engineering Research
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• v.25 no.6
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• pp.551-556
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• 2004

The purpose of this study was to suggest a systematic and scientific method for measurement of children's growth development, in which the accuracy of existing diagnosis method has not been concretely examined yet. The most popular method for diagnosis of children's growth is to analyze the opening degree of growth plate in each joint by X-ray image. However, X-ray method has some disadvantages; it is impossible to measure the diagnosis of growth periodically and repeatedly due to the radiation problem. Hence, this study introduced a profile analysis and the algorithm of analyzing the image of growth plate with the BUA(Broadband Ultrasound Attenuation) of calcaneus, to verify the possibility of alternative ultrasonic method harmless to human body. We obtained the images of growth plate in proximal tibiae, phalanges, and calcanei of 269 children (7∼16 years old) with X-ray. And the image of growth plate in calcanei was also obtained front those children with ultrasound. The results showed that the time of the opening degree of growth plate in each joint was almost consistent between X-ray and ultrasonic images. Also, the images of growth plate measured by X-ray and ultrasound showed the high correlation. Therefore, it is expected that the algorithm of ultrasonic profile analysis introduced in this study can replace the existing X-ray method to measure the growth plate correctly.