• Title/Summary/Keyword: Needle Detection

Search Result 94, Processing Time 0.025 seconds

Diagnostic Pitfalls in Breast Fine Needle Aspiration Cytology: False Positive and False Negative (유방 세침흡인 세포검사의 진단적 함정: 위양성과 위음성)

  • Park, Kyeong-Mee
    • The Korean Journal of Cytopathology
    • /
    • v.18 no.2
    • /
    • pp.112-118
    • /
    • 2007
  • Fine needle aspiration cytology (FNAC) has become a highly preferred, minimally invasive diagnostic tool of choice in the diagnosis of a palpable breast mass owing to its sensitivity, specificity, cost-effectiveness, and expediency. Although breast needle biopsies have been widely employed recently due to the increased detection rate of non-palpable early lesions, the importance of the use of FNAC cannot be underestimated. It comprises part of the diagnostic triad for the breast along with a physical examination and mammography, which together contribute to an increasing diagnostic accuracy. The differential diagnosis of a benign and malignant lesion is of the utmost importance in the diagnosis of breast lesions, and therefore the understanding of the possible diagnostic pitfalls is of great importance.

Location and Frequency Domain Detection of Corona Discharge Point in Oil Using AE Sensor (AE센서를 이용한 유중 코로나방전점 위치 및 주파수 영역 검출)

  • 이상우;김성훈;김인식;김기채;박원주;이광식;이동인
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
    • /
    • 1999.11a
    • /
    • pp.127-131
    • /
    • 1999
  • In this paper, using a wide-band AE sensor with the frequency range from 100[kHz], the frequency spectra of AE signals generated from the corona discharges of the needle-plane electrode was analyzed to determine the proper ultrasonic sensor. We also examined the relationship between the magnitude of corona discharge and the magnitude of AE signals in peak-to-peak value under the application of 60[Hz] AC high-voltage in oil. From these results, the main frequency spectra of AE signals emitted from the corona discharges of the needle-plane gap were found to be 130[kHz] by the fast fourier transform. The magnitude of AE signals was proportional to the magnitude of corona discharge and discharge current pulse with increasing the applied voltages. Also the detection of corona discharge point location by AE signals was found to be possible by using two sensors.

  • PDF

Detection of Needles in Meat using X-Ray Images and Convolution Neural Networks (X-선 영상과 합성곱 신경망을 이용한 육류 내의 바늘 검출)

  • Ahn, Jin-Ho;Jang, Won-Jae;Lee, Won-Hee;Kim, Jeong-Do
    • Journal of Sensor Science and Technology
    • /
    • v.29 no.6
    • /
    • pp.427-432
    • /
    • 2020
  • The most lethal foreign body in meat is a needle, and X-ray images are used to detect it. However, because the difference in thickness and fat content is severe depending on the type of meat and the part of the meat, the shade difference and contrast appear severe. This problem causes difficulty in automatic classification. In this paper, we propose a method for generating training patterns by efficient pre-processing and classifying needles in meat using a convolution neural network. Approximately 24000 training patterns and 4000 test patterns were used to verify the proposed method, and an accuracy of 99.8% was achieved.

Utility of Digital Rectal Examination, Serum Prostate Specific Antigen, and Transrectal Ultrasound in the Detection of Prostate Cancer: A Developing Country Perspective

  • Kash, Deep Par;Lal, Murli;Hashmi, Altaf Hussain;Mubarak, Muhammed
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.7
    • /
    • pp.3087-3091
    • /
    • 2014
  • Purpose: To determine the utility of digital rectal examination (DRE), serum total prostate specific antigen (tPSA) estimation, and transrectal ultrasound (TRUS) for the detection of prostate cancer (PCa) in men with lower urinary tract symptoms (LUTS). Materials and Methods: All patients with abnormal DRE, TRUS, or serum tPSA >4ng/ml, in any combination, underwent TRUS-guided needle biopsy. Eight cores of prostatic tissue were obtained from different areas of the peripheral prostate and examined histopathologically for the nature of the pathology. Results: PCa was detected in 151 (50.3%) patients, remaining 149 (49.7%) showed benign changes with or without active prostatitis. PCa was detected in 13 (56.5%), 9 (19.1%), 26 (28.3%), and 103 (74.6%) of patients with tPSA <4 ng/ml, 4-10 ng/ml, 10-20 ng/ml and >20 ng/ml respectively. Only 13 patients with PCa had abnormal DRE and TRUS with serum PSA <4 ng/ml. The detection rate was highest in patients with tPSA >20 ng/ml. The association between tPSA level and cancer detection was statistically significant (p<0.01). Among 209 patients with abnormal DRE and raised serum PSA, PCa was detected in 128 (61.2%). Conclusions: The incidence of PCa increases with increasing serum level of tPSA. The overall screening and detection rate can be further improved by using DRE, TRUS and TRUS-guided prostate needle biopsies.

Detection of Partial Discharges by a Monopole Antenna in Insulation Oil (모노폴 안테나를 이용한 유중 부분방전의 검출)

  • Park, Dae-Won;Lee, Jung-Yoon;Kil, Gyung-Suk
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.25 no.9
    • /
    • pp.727-731
    • /
    • 2012
  • This paper dealt with the measurement and analysis of electromagnetic waves radiated from a partial discharge (PD) source in insulation oil to apply condition monitoring of oil-immersed transformers. Two types of narrow-band monopole antennas with the resonant frequency of a 500 MHz and a 1 GHz were designed and fabricated. Also, a needle-plane electrode system was manufactured to simulate PDs and the curvature radius of the needle is 10 ${\mu}m$ and the diameter of the plane is 60 mm. Electromagnetic wave was measured by the PD measurement system with the monopole antennas. Detection sensitivity of the fabricated antenna was compared for the same PD magnitude; 620 $mV_{peak}$ for the 500 MHz antenna and 960 $mV_{peak}$ for the 1 GHz antenna to the PD magnitude of 74 pC. Consequently, the 1 GHz monopole antenna is more effective to detect PDs in oil-immersed transformers.

Fine Needle Aspiration Cytology of Thyroid Nodules: Assessment of diagnostic accuracy and evaluation of each cytologic diagnosis (갑상선 결절의 세침흡인 세포검사: 진단성적의 검토 및 세포학적 진단의 평가)

  • Park, In-Ae;Ham, Eui-Keun
    • The Korean Journal of Cytopathology
    • /
    • v.10 no.1
    • /
    • pp.43-53
    • /
    • 1999
  • We retrospectively reviewed the results of 1,850 fine needle aspiration cytology(FNAC) of thyroid nodules performed from 1990 to 1991 in the Department of Pathology, Seoul National University Hospital. Among 1,528 cases and 322 cases aspirated by clinicians and a pathologist, 465 cases(30.4%) and 13 cases(4.0%) of the aspirates were inadequate, respectively. In 227 cases, correlation of the FNAC diagnosis and histologic diagnosis was done. Excluding the inadequate cases, the sensitivity nor the detection of neoplasm(malignancy together with follicular adenoma) was 86.4% and the specificity was 70.7%. The overall diagnostic accuracy was 79.0%. There were 16 false-positive cases(7.0%), and 19 false-negative cases(8.4%). The predictive value of each cytologic diagnosis was 92% in papillary carcinoma, and 100%, in Hashimoto's thyroiditis. The expectancy of malignancy was 52.8% in "suspicious malignancy" and 26.7% in "atypical lesion".

  • PDF

Identifying Analog Gauge Needle Objects Based on Image Processing for a Remote Survey of Maritime Autonomous Surface Ships (자율운항선박의 원격검사를 위한 영상처리 기반의 아날로그 게이지 지시바늘 객체의 식별)

  • Hyun-Woo Lee;Jeong-Bin Yim
    • Journal of Navigation and Port Research
    • /
    • v.47 no.6
    • /
    • pp.410-418
    • /
    • 2023
  • Recently, advancements and commercialization in the field of maritime autonomous surface ships (MASS) has rapidly progressed. Concurrently, studies are also underway to develop methods for automatically surveying the condition of various on-board equipment remotely to ensure the navigational safety of MASS. One key issue that has gained prominence is the method to obtain values from analog gauges installed in various equipment through image processing. This approach has the advantage of enabling the non-contact detection of gauge values without modifying or changing already installed or planned equipment, eliminating the need for type approval changes from shipping classifications. The objective of this study was to identify a dynamically changing indicator needle within noisy images of analog gauges. The needle object must be identified because its position significantly affects the accurate reading of gauge values. An analog pressure gauge attached to an emergency fire pump model was used for image capture to identify the needle object. The acquired images were pre-processed through Gaussian filtering, thresholding, and morphological operations. The needle object was then identified through Hough Transform. The experimental results confirmed that the center and object of the indicator needle could be identified in images of noisy analog gauges. The findings suggest that the image processing method applied in this study can be utilized for shape identification in analog gauges installed on ships. This study is expected to be applicable as an image processing method for the automatic remote survey of MASS.

Detection and Measurement of Retinoic Acid in Human Liver Samples (간 조직내의 Retinoic Acid 검출 및 측정 방법)

  • 김초일
    • Journal of Nutrition and Health
    • /
    • v.24 no.3
    • /
    • pp.199-205
    • /
    • 1991
  • Retinoic acid. the active metabolite of vitamin A. was detected in the human liver for the first time using a new method. A rapid and sensitive technique has been developed using gradient-elution. reverse-phase high performance liquid chromatography. This assay. with simultaneous multiwavelength detection at 294nm, 325nm and 450nm after saponifcation of liver samples. allows us seperation and quantitation of vitamin E, retinoic acid, total retinoids and various carotenoids in one small sample. The proportion of retinoic acid to total retinoids in human liver appears to be quite $consistent(2.4\pm0.2%$ ). With low vitamin A storage in liver, detection at another wavelenth 354nm would increase the sensitivity for retinoic acid of small quantity This method of analysis could be used for other tissues like red blood cells, plasma or serum, also. Hepatic retinoic acid level with total retinoids and carotenoids would serve a better indicator of functional vitamin A nutriture especially for those with disease requiring needle biopsy of liver.

  • PDF

Diagnostic Accuracy of Ultrasonography in Differentiating Benign and Malignant Thyroid Nodules Using Fine Needle Aspiration Cytology as the Reference Standard

  • Alam, Tariq;Khattak, Yasir Jamil;Beg, Madiha;Raouf, Abdul;Azeemuddin, Muhammad;Khan, Asif Alam
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.22
    • /
    • pp.10039-10043
    • /
    • 2014
  • Background: In Pakistan thyroid cancer is responsible for 1.2% cases of all malignant tumors. Ultrasonography (US) is helpful in detecting cancerous thyroid nodules on basis of different features like echogenicity, margins, microcalcifications, size, shape and abnormal neck lymph nodes. We therefore aimed to calculate diagnostic accuracy of ultrasound in detection of carcinoma in thyroid nodules taking fine needle aspiration cytology as the reference standard. Materials and Methods: A cross-sectional analytical study was designed to prospectively collect data from December 2010 till December 2012 from the Department of Radiology in Aga Khan University Hospital, Karachi, Pakistan. A total of 100 patients of both genders were enrolled after informed consent via applying non-probability consecutive sampling technique. Patients referred to Radiology department of Aga Khan University to perform thyroid ultrasound followed by fine-needle aspiration cytology of thyroid nodules were included. They were excluded if proven for thyroid malignancy or if their US or FNAC was conducted outside our institution. Results: The subjects comprised 76 (76%) females and 24 males. Mean age was $41.8{\pm}SD$ 12.3 years. Sensitivity and specificity with 95%CI of ultrasound in differentiating malignant thyroid nodule from benign thyroid nodule calculated to be 91.7% (95%CI, 0.72-0.98) and 78.94% (0.68-0.87) respectively. Reported positive predictive value and negative PV were 57.9% (0.41-0.73) and 96.8% (0.88-0.99) and overall accuracy was 82%. Likelihood ratio (LR) positive was computed to be 4.3 and LR negative was 0.1. Conclusions: Ultrasonography has a high diagnostic accuracy in detecting malignancy in thyroid nodules on the basis of features like echogenicity, margins, micro calcifications and shape.

Digital subtraction angiography vs. real-time fluoroscopy for detection of intravascular injection during transforaminal epidural block

  • Park, Kibeom;Kim, Saeyoung
    • Journal of Yeungnam Medical Science
    • /
    • v.36 no.2
    • /
    • pp.109-114
    • /
    • 2019
  • Background: Transforaminal epidural block (TFEB) is an effective treatment option for radicular pain. To reduce complications from intravascular injection during TFEB, use of imaging modalities such as real-time fluoroscopy (RTF) or digital subtraction angiography (DSA) has been recommended. In this study, we investigated whether DSA improved the detection of intravascular injection during TFEB at the whole spine level compared to RTF. Methods: We prospectively examined 316 patients who underwent TFEB. After confirmation of final needle position using biplanar fluoroscopy, 2 mL of nonionic contrast medium was injected at a rate of 0.5 mL/s under RTF; 30 s later, 2 mL of nonionic contrast medium was injected at a rate of 0.5 mL/s under DSA. Results: Thirty-six intravascular injections were detected for an overall rate of 11.4% using RTF, with 45 detected for a rate of 14.2% using DSA. The detection rate using DSA was statistically different from that using RTF (p=0.004). DSA detected a significantly higher proportion of intravascular injections at the cervical level than at the thoracic (p=0.009) and lumbar (p=0.011) levels. Conclusion: During TFEB at the whole spine level, DSA was better than RTF for the detection of intravascular injection. Special attention is advised for cervical TFEB, because of a significantly higher intravascular injection rate at this level than at other levels.