• 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.

• Korean Journal of Bronchoesophagology
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• v.17 no.1
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• pp.19-22
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• 2011

Endoscopic ultrasound in the diagnosis of esophageal carcinoma is an indispensable procedure, not only to discuss the preoperative staging of the lesion, but also to evaluate the therapeutic effect of chemo-radiation therapy. The recent increase in the incidence of superficial esophageal cancer and promising developments in potentially curative endoscopic therapies have placed EUS to a central position in decision making. Recent data have called into question the staging accuracy of EUS to distinguish mucosal from submucosal lesions, particularly in patients with early disease. In those cases, diagnostic endoscopic resection may be useful for staging and curative in superficial lesions. Nonetheless, EUS has been regarded as the most accurate staging tool and should be performed to identify potential candidates for endoscopic resection.

• The Journal of the Acoustical Society of Korea
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• v.29 no.2E
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• pp.73-85
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• 2010

In the diagnostic ultrasound (US) transducer technology, the high frequency US(HFUS) transducer over 20 MHz is one of the current issues to be pursued for better resolution with the expense of penetration. HFUS single element transducers and the mechanical scanning systems for imaging are reviewed, and HFUS array transducers are also briefly summarized. HFUS applications such as the human applications in ophthalmology and dermatology and small animal applications for research purposes are reviewed with vascular and blood imaging in this paper.

• Korean Journal of Radiology
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• v.22 no.12
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• pp.2006-2016
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• 2021

The expanding scope of interventional musculoskeletal procedures has resulted in increased pressure on general radiologists. The confidence of general radiologists in performing ultrasound-guided musculoskeletal procedures varies with their clinical exposure. This didactic review provides a methodologically and clinically oriented approach to enhancing user understanding and confidence in performing ultrasound-guided musculoskeletal procedures. The body of the text is accompanied by figures depicting the procedural approach, injection site, and labeled ultrasonography images. This paper aims to provide a teaching and bedside aid for education on and the execution of musculoskeletal procedures to ensure the provision of quality health care.

• Korean Journal of Radiology
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• v.25 no.2
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• pp.134-145
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• 2024

Abnormalities on breast ultrasound (US) images which do not meet the criteria for masses are referred to as nonmass lesions. These features and outcomes have been investigated in several studies conducted by Asian researchers. However, the term "nonmass" is not included in the American College of Radiology (ACR) Breast Imaging Reporting and Data System (BI-RADS) 5th edition for US. According to the Japan Association of Breast and Thyroid Sonology guidelines, breast lesions are divided into mass and nonmass. US findings of nonmass abnormalities are classified into five subtypes: abnormalities of the ducts, hypoechoic areas in the mammary glands, architectural distortion, multiple small cysts, and echogenic foci without a hypoechoic area. These findings can be benign or malignant; however, focal or segmental distributions and presence of calcifications suggest malignancy. Intraductal, invasive ductal, and lobular carcinomas can present as nonmass abnormalities. For the nonmass concept to be included in the next BI-RADS and be widely accepted in clinical practice, standardized terminologies, an interpretation algorithm, and outcome-based evidence are required for both screening and diagnostic US.

• Korean Journal of Radiology
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• v.21 no.8
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• pp.955-966
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• 2020

Ultrasound (US) is an attractive diagnostic approach to identify both common and uncommon nipple pathologies, such as duct ectasia, nipple abscess, nipple leiomyoma, nipple adenoma, fibroepithelial polyp, ductal carcinoma in situ (restricted to nipple), invasive carcinoma, and Paget's disease. US is the reliable first-line imaging technique to assess nipple pathologies. It is useful to identify and characterize nipple lesions. Additionally, we have presented the mammography and MRI outcomes correlated with histopathologic features for the relevant cases.

• Journal of Electrical Engineering and Technology
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• v.11 no.2
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• pp.499-507
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• 2016

Medical imaging techniques such as Magnetic Resonance Imaging (MRI), Computed Tomography (CT) and Ultrasound (US) produce a large amount of digital medical images. Hence, compression of digital images becomes essential and is very much desired in medical applications to solve both storage and transmission problems. But at the same time, an efficient image compression scheme that reduces the size of medical images without sacrificing diagnostic information is required. This paper proposes a novel threshold-based medical image compression algorithm to reduce the size of the medical image without degradation in the diagnostic information. This algorithm discusses a novel type of thresholding to maximize Compression Ratio (CR) without sacrificing diagnostic information. The compression algorithm is designed to get image with high optimum compression efficiency and also with high fidelity, especially for Peak Signal to Noise Ratio (PSNR) greater than or equal to 36 dB. This value of PSNR is chosen because it has been suggested by previous researchers that medical images, if have PSNR from 30 dB to 50 dB, will retain diagnostic information. The compression algorithm utilizes one-level wavelet decomposition with threshold-based coefficient selection.

• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2007.05a
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• pp.147-147
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• 2007

• The Korean Journal of Pain
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• v.20 no.2
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• pp.111-115
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• 2007

Background: Selective diagnostic blocks of the medial branches of the dorsal primary ramus are usually performed under the guidance of fluoroscopic or computed tomography. Recently, however, ultrasound guidance has been suggested as an altemative method. In this study, the distances between the vertebral structures were measured and compared with the values measured using magnetic resonance imaging (MRI) to assess the clinical feasibility of using ultrasound-guided block in Korean patients. Methods: Five male and 15 female patients were enrolled in this study. The target point of the medial branch block in our study was the groove at the base of the superior articular process, We measured the depth from the skin to the target point at the transverse process (d-TP) and to the most superficial point of the superior articular process (d-AP). Results: The d-TP and d-AP values measured under ultrasound guidance were concordant with the values measured using MRI. Conclusions: The images of the bony landmarks obtained under ultrasound examination could be useful for ultrasound-guided lumbar medial branch block.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.10
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• pp.4169-4173
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• 2014

Background: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is highly accurate in diagnosing mediastinal lymphadenopathies of lung cancer and benign disorders. However, the utility of EBUS-TBNA in the diagnosis of mediastinal lymphomas is unclear. The aim of this study was to determine the diagnostic value of EBUS-TBNA in patients with suspected lymphoma. Materials and Methods: Sixty-eight patients with isolated mediastinal lymphadenopathy and suspected of lymphoma were included in the study. EBUS-TBNA was performed on outpatients under moderate sedation. The sensitivity, specificity, negative predictive value and diagnostic accuracy of EBUS-TBNA were calculated. Results: Sixty-four patients were diagnosed by EBUS-TBNA, but four patients with non-diagnostic EBUS-TBNA required surgical procedures. Thirty-five (51.5%) patients had sarcoidosis, six (8.8%) had reactive lymphadenopathy, nine (13.3%) had tuberculosis, one (1.5%) had squamous cell carcinoma, two (2.9%) had sarcoma and fifteen (22%) had lymphoma (follicular center cell, large B-cell primary, and Hodgkin lymphomas in three, two, and ten, respectively). Of the 15 lymphoma patients, thirteen were diagnosed by EBUS and two by thoracotomy and mediastinoscopy. The sensitivity, specificity, negative predictive value, and diagnostic accuracy of EBUS-TBNA for the diagnosis of lymphoma were calculated as 86.7%, 100%, 96.4%, and 97%, respectively. Conclusions: EBUS-TBNA can be employed in the diagnosis of mediastinal lymphoma, instead of more invasive surgical procedures.