• 제목/요약/키워드: Ultrasound sensitivity

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초음파 센싱 방식의 spirometer에 대한 sensitivity 향상 (Sensitivity Elevation about Spirometer Using Ultrasound Sensing Method)

  • 한승헌;김영길
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2004년도 춘계종합학술대회
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    • pp.269-272
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    • 2004
  • 초음파 센서를 이용한 호흡측정방식은 관성 및 압력의 오차의 영향을 거의 받지 않고, 반영구적으로 사용이 가능한 호흡기기이다. 초음파의 특성을 이용한 것으로 송수신시 초음파의 매질인 공기의 흐름에 의한 반송형식인 초음파의 전달속도 차이를 이용하여 호흡량 및 흐름을 detecting하는 기술이다. 본 논문에서는 환자를 중심으로 측정이 이루어져야 하기 때문에 센서의 송수신시 일어나는 신호의 sensitivity를 향상시켜서 약한 호흡에도 dectection이 가능하도록 하였다.

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Pre-Operative Evaluation of Ovarian Tumors by Risk of Malignancy Index, CA125 and Ultrasound

  • Arun-Muthuvel, Veluswamy;Jaya, Vijayaraghavan
    • Asian Pacific Journal of Cancer Prevention
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    • 제15권6호
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    • pp.2929-2932
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    • 2014
  • Purpose: To evaluate the diagnostic performances of risk of malignancy index (RMI), CA-125 and ultrasound score in differentiating between benign and borderline or malignant ovarian tumors and find the best diagnostic test for referral of suspected malignant ovarian cases to gynaecologic oncologists. Materials and Methods: This prospective study covered 467 women with pelvic tumors scheduled for surgery at our hospital between July 2011 and July 2013. The RMI was obtained from ultrasound score, CA125 and menopausal status. The diagnostic values of each parameter and the RMI were determined and compared using Statistical Packages for Social Sciences Version 14.0.1. Results: In our study, 61% of ovarian tumors were malignant in the post-menopausal age group. RMI with a cut-off 150 had sensitivity of 84% and specificity of 97% in detecting ovarian cancer. CA-125>30 had a sensitivity of 84% and a specificity of 83%. An ultrasound score more than 2 had a sensitivity of 96% and specificity of 81%. RMI had the least false malignant cases thus avoiding unnecessary laparotomies. Ultrasound when used individually had the best sensitivity but poor specificity. Conclusions: Our study has demonstrated the RMI to be an easy, simple and applicable method in the primary evaluation of patients with pelvic masses. It can be used to refer suspected malignant patients to be operated by a gynaecologic oncologist. Other models of preoperative evaluation should be developed to improve the detection of early stage invasive, borderline and non-epithelial ovarian cancers.

초음파 센싱 방식의 spirometer에 대한 sensitivity 향상 연구 (A Study on the Sensitivity Elevation about Spirometer Using Ultrasound Sensing Method)

  • 한승헌;김영길
    • 한국정보통신학회논문지
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    • 제9권1호
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    • pp.204-209
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    • 2005
  • 초음파 센서를 이용한 호흡측정방식은 관성 및 압력의 오차의 영향을 거의 받지 않고, 반영구적으로 사용이 가능한 호흡기기이다. 초음파의 특성을 이용한 것으로 송수신시 초음파의 매질인 공기의 흐름에 의한 반송형식인 초음파의 전달속도 차이를 이용하여 호흡량 및 흐름을 detecting하는 기술이다. 본 논문에서는 환자를 중심으로 측정이 이루어져야 하기 때문에 센서의 송수신시 일어나는 신호의 sensitivity를 향상시켜서 약한 호흡에도 dectection이 가능하도록 시스템의 성능을 향상시켰다.

지간 신경종에서 보존적 치료 및 수술적 치료의 임상적 결과 (Clinical Result of Conservative Treatment and Operative Treatment for Interdigital Neuroma)

  • 이진우;한승환;서동석
    • 대한족부족관절학회지
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    • 제10권1호
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    • pp.31-36
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    • 2006
  • Purpose: To evaluate the usefulness of ultrasound and MRI in diagnosing Morton's Neuroma, and the effect and significance of stepwise treatment. Materials and Methods: Out of all patients suspected of Morton's neuroma through history taking and physical examination, 77 patients (84 feet, 95 lesions) in whom Morton's neuroma was confirmed by ultrasound or MR imaging study or was clinically suspected with negative imaging studies, and followed up for over 3 months were included. In all cases, history taking and imaging study were done, and by comparison with operative findings of the patients, the sensitivity of ultrasound and MRI was checked. Postoperative evaluation was done using the AOFAS scale. The patient's satisfaction was also examined. Results: Morton's neuroma occurred most frequently at the $3^{rd}$ web space of the foot (56%), followed by the $2^{nd}$ web space (44%). Out of 15 cases suspected of morton's neuroma through ultrasound study, 13 were pathologically positive showing a sensitivity of 85.7%. Out of 16 cases suspected of morton's neuroma through MRI, 14 were pathologically positive showing a sensitivity of 83.3%. There was no significant difference in sensitivity between the two imaging modalities. Conclusion: In diagnosing Morton's neuroma, ultrasound examination had a similar sensitivity with MRI, therefore can be used as a screening study.

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Sensitivity Enhancement of Spirometer Employing Ultrasonic Method

  • Han, Seung-Heon;Kim, Young-Kil
    • 대한의용생체공학회:의공학회지
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    • 제26권6호
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    • pp.351-356
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    • 2005
  • Respiration measurement method using an ultrasound sensor is influenced very little by an error of inertia and pressure. This device measures the amount and flow of respiration using a delivery speed difference of the ultrasound waves that are a return format by the pneumatic stream that is a flogging of ultrasound waves during transmission and receipt as having used a characteristic of ultrasound waves. This paper examines improving the sensor's sensitivity during transmission and receipt of the signal. Because the measurement must be performed on patients, clinicians need to be sure that it is accurately measuring even very weak breathing.

Value of Contrast-Enhanced Ultrasonography in the Differential Diagnosis of Enlarged Lymph Nodes: a Meta-Analysis of Diagnostic Accuracy Studies

  • Jin, Ya;He, Yu-Shuang;Zhang, Ming-Ming;Parajuly, Shyam Sundar;Chen, Shuang;Zhao, Hai-Na;Peng, Yu-Lan
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권6호
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    • pp.2361-2368
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    • 2015
  • Objective: To evaluate the diagnostic accuracy of contrast-enhanced ultrasonography (CEUS) in differentiating between benign and malignant enlarged lymph nodes using meta-analysis. Materials and Methods: Pubmed, Embase, SCI and Cochrane databases were searched for studies (up to September 1, 2014) reporting the diagnostic performance of CEUS in discriminating between benign and malignant lymph nodes. Inclusion criteria were: prospective study; histopathology as the reference standard; and sufficient data to construct $2{\times}2$ contingency tables. Methodological quality was assessed using Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2). Patient clinical characteristics, sensitivity and specificity were extracted. The summary receiver operating characteristic curve was used to examine the accuracy of CEUS. A meta-analysis was performed to evaluate the clinical utility in identification of benign and malignant lymph nodes. Sensitivity analysis was performed after omitting outliers identified in a bivariate boxplot and publication bias was assessed with Egger testing. Results: The pooled sensitivity, specificity and AUROC were 0.92 (95%CI, 0.85-0.96), 0.91 (95%CI, 0.82-0.95) and 0.97 (95%CI, 0.95-0.98), respectively. After omitting 3 outlier studies, heterogeneity decreased. Sensitivity analysis demonstrated no disproportionate influences of individual studies. Publication bias was not significant. Conclusions: CEUS is a promising diagnostic modality in differentiating between benign and malignant lymph nodes and can potentially reduce unnecessary fine-needle aspiration biopsies of benign nodes.

Comparative Efficacy of Four Imaging Instruments for Breast Cancer Screening

  • Mehnati, Parinaz;Tirtash, Maede Jafari
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권15호
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    • pp.6177-6186
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    • 2015
  • Sensitivity and specificity are the two most important indicators in selection of medical imaging devices for cancer screening. Breast images taken by conventional or digital mammography, ultrasound, MRI and optical mammography were collected from 2,143,852 patients. They were then studied and compared for sensitivity and specificity results. Optical mammography had the highest sensitivity (p<0.001 and p<0.006) except with MRI. Digital mammography had the highest specificity for breast cancer imaging. A comparison of specificity between digital mammography and optical mammography was significant (p<0.021). If two or more breast diagnostic imaging tests are requested the overall sensitivity and specificity will increase. In this literature review study patients at high-risk of breast cancer were studied beside normal or sensitive women. The image modality performance of each breast test was compared for each.

Role of Ultrasound in Characterization of Ovarian Masses

  • Hafeez, Saima;Sufian, Saira;Beg, Madiha;Hadi, Quratulain;Jamil, Yasir;Masroor, Imrana
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권1호
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    • pp.603-606
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    • 2013
  • Background: Ovarian cancer is the second most common malignancy in Pakistani women, accounting for 4% of all cancers in the female population. The aim of this study was to determine sensitivity, specificity, positive and negative predictive values and 95% confidence intervals for ultrasound in characterization of ovarian masses in patients presenting at public and private tertiary care hospitals in Karachi, Pakistan. Materials and Methods: We adopted a cross-sectional analytical study design to retrospectively collect data from January 2009-11 from medical records of two tertiary care hospitals. Using a non-probability purposive sampling technique, we recruited a sample of 86 women aged between 15 and 85 years fulfilling inclusion criteria with histopathologically proven ovarian masses presenting for an ultrasound examination in our radiology departments. Results: Our retrospective data depicted sensitivity and specificity of ultrasound to be 90.7%, 95%CI (0.77, 0.97) and 91.4%, 95%CI (0.76, 0.98) respectively. Positive predictive value was 93%, 95%CI (0.79, 0.98) and negative predictive value was 89%, 95%CI (0.73, 0.96). A total of 78 ovarian masses were detected, out of which 42 were malignant and 36 were benign. Conclusions: Results of our study further reinforce the conclusion that ultrasound should be used as an initial modality of choice in the workup of every woman suspected of having an ovarian mass. It not only results in decreasing the mortality but also avoids unnecessary surgical interventions.

Value of Ultrasound Elastography in Assessment of Enlarged Cervical Lymph Nodes

  • Teng, Deng-Ke;Wang, Hui;Lin, Yuan-Qiang;Sui, Guo-Qing;Guo, Feng;Sun, Li-Na
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권5호
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    • pp.2081-2085
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    • 2012
  • Background: To investigate the value of ultrasound elastography (UE) in the differentiation between benign and malignant enlarged cervical lymph nodes (LNs). Methods: B-mode ultrasound, power Doppler imaging and UE were examined to determine LN characteristics. Two kinds of methods, 4 scores of elastographic classification and a strain ratio (SR) were used to evaluate the ultrasound elastograms. Results: The cutoff point of SR had high utility in differential diagnosis of benign and malignant of cervical lymph nodes, with good sensitivity, specificity and accuracy. Conclusion: UE is an important aid in differential diagnosis of benign and malignant cervical LNs.

Dual Functional Gd(III)-DOTA Liposomes for Cancer Therapy and Diagnosis as a Theragnostic Carrier

  • Han, Hee Dong;Jung, Suk Hyun;Seong, Hasoo;Cho, Sun Hang;Shin, Byung Cheol
    • Bulletin of the Korean Chemical Society
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    • 제34권1호
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    • pp.154-158
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    • 2013
  • Development of dual functional liposome has been studied for cancer theragnostics. Therefore, we focused on ultrasound-sensitive liposomes with doxorubicin (DOX) and gadolinium (Gd) as a theragnostic carrier having a potential for cancer therapy and diagnosis. In this study, Gd(III)-DOTA-modified sonosensitive liposomes (GL) was developed using chemically synthesized Gd(III)-DOTA-DPPE lipid. Sonosensitivity of GL to 1 MHz ultrasound induced 25% of DOX release. The relaxivities ($r_1$) of GL were $7.33-10.34\;mM^{-1}s^{-1}$, which was higher than that of MR-bester$^{(R)}$. Intracellular delivery of DOX from GL by ultrasound irradiation was evaluated according to ultrasound intensity, resulting in increase of uptake of DOX released from ultrasound-triggered GLs compared to GL3 or Doxil$^{(R)}$ without ultrasound. Taken together, this study shows that the paramagnetic and sonosensitive liposomes, GL, is a novel and highly effective delivery system for drug with the potential for broad applications in human disease.