• Title/Summary/Keyword: B-scan

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Accurate Measurement of Agatston Score Using kVp-Independent Reconstruction Algorithm for Ultra-High-Pitch Sn150 kVp CT

  • Xi Hu;Xinwei Tao;Yueqiao Zhang;Zhongfeng Niu;Yong Zhang;Thomas Allmendinger;Yu Kuang;Bin Chen
    • Korean Journal of Radiology
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    • v.22 no.11
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    • pp.1777-1785
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    • 2021
  • Objective: To investigate the accuracy of the Agatston score obtained with the ultra-high-pitch (UHP) acquisition mode using tin-filter spectral shaping (Sn150 kVp) and a kVp-independent reconstruction algorithm to reduce the radiation dose. Materials and Methods: This prospective study included 114 patients (mean ± standard deviation, 60.3 ± 9.8 years; 74 male) who underwent a standard 120 kVp scan and an additional UHP Sn150 kVp scan for coronary artery calcification scoring (CACS). These two datasets were reconstructed using a standard reconstruction algorithm (120 kVp + Qr36d, protocol A; Sn150 kVp + Qr36d, protocol B). In addition, the Sn150 kVp dataset was reconstructed using a kVp-independent reconstruction algorithm (Sn150 kVp + Sa36d, protocol C). The Agatston scores for protocols A and B, as well as protocols A and C, were compared. The agreement between the scores was assessed using the intraclass correlation coefficient (ICC) and the Bland-Altman plot. The radiation doses for the 120 kVp and UHP Sn150 kVp acquisition modes were also compared. Results: No significant difference was observed in the Agatston score for protocols A (median, 63.05; interquartile range [IQR], 0-232.28) and C (median, 60.25; IQR, 0-195.20) (p = 0.060). The mean difference in the Agatston score for protocols A and C was relatively small (-7.82) and with the limits of agreement from -65.20 to 49.56 (ICC = 0.997). The Agatston score for protocol B (median, 34.85; IQR, 0-120.73) was significantly underestimated compared with that for protocol A (p < 0.001). The UHP Sn150 kVp mode facilitated an effective radiation dose reduction by approximately 30% (0.58 vs. 0.82 mSv, p < 0.001) from that associated with the standard 120 kVp mode. Conclusion: The Agatston scores for CACS with the UHP Sn150 kVp mode with a kVp-independent reconstruction algorithm and the standard 120 kVp demonstrated excellent agreement with a small mean difference and narrow agreement limits. The UHP Sn150 kVp mode allowed a significant reduction in the radiation dose.

Analysis of Image Distortion on Magnetic Resonance Diffusion Weighted Imaging

  • Cho, Ah Rang;Lee, Hae Kag;Yoo, Heung Joon;Park, Cheol-Soo
    • Journal of Magnetics
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    • v.20 no.4
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    • pp.381-386
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    • 2015
  • The purpose of this study is to improve diagnostic efficiency of clinical study by setting up guidelines for more precise examination with a comparative analysis of signal intensity and image distortion depending on the location of X axial of object when performing magnetic resonance diffusion weighted imaging (MR DWI) examination. We arranged the self-produced phantom with a 45 mm of interval from the core of 44 regent bottles that have a 16 mm of external diameter and 55 mm of height, and were placed in 4 rows and 11 columns in an acrylic box. We also filled up water and margarine to portrait the fat. We used 3T Skyra and 18 Channel Body array coil. We also obtained the coronal image with the direction of RL (right to left) by using scan slice thinkness 3 mm, slice gap: 0mm, field of view (FOV): $450{\times}450mm^2$, repetition time (TR): 5000 ms, echo time (TE): 73/118 ms, Matrix: $126{\times}126$, slice number: 15, scan time: 9 min 45sec, number of excitations (NEX): 3, phase encoding as a diffusion-weighted imaging parameter. In order to scan, we set b-value to $0s/mm^2$, $400s/mm^2$, and $1,400s/mm^2$, and obtained T2 fat saturation image. Then we did a comparative analysis on the differences between image distortion and signal intensity depending on the location of X axial based on iso-center of patient's table. We used "Image J" as a comparative analysis programme, and used SPSS v18.0 as a statistic programme. There was not much difference between image distortion and signal intensity on fat and water from T2 fat saturation image. But, the average value depends on the location of X axial was statistically significant (p < 0.05). From DWI image, when b-value was 0 and 400, there was no significant difference up to $2^{nd}$ columns right to left from the core of patient's table, however, there was a decline in signal intensity and image distortion from the $3^{rd}$ columns and they started to decrease rapidly at the $4^{th}$ columns. When b-value was 1,400, there was not much difference between the $1^{st}$ row right to left from the core of patient's table, however, image distortion started to appear from the $2^{nd}$ columns with no change in signal intensity, the signal was getting decreased from the $3^{rd}$ columns, and both signal intensity and image distortion started to get decreased rapidly. At this moment, the reagent bottles from outside out of 11 reagent bottles were not verified from the image, and only 9 reagent bottles were verified. However, it was not possible to verify anything from the $5^{th}$ columns. But, the average value depends on the location of X axial was statistically significant. On T2 FS image, there was a significant decline in image distortion and signal intensity over 180mm from the core of patient's table. On diffusion-weighted image, there was a significant decline in image distortion and signal intensity over 90 mm, and they became unverifiable over 180 mm. Therefore, we should make an image that has a diagnostic value from examinations that are hard to locate patient's position.

Multiple FBG Sensor System Using Code Division Multiple Access (코드분할 다중화 방식을 이용한 다중 광섬유 브래그 격자 센서 시스템)

  • Ryu, Hyung-Don;Lee, Ho-Joon
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.38 no.8
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    • pp.27-33
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    • 2001
  • The performance of the ordinary Fiber Bragg Grating(FBG) sensor strain measurement system, which uses Fabry-Perot filter for scanning wavelength, has limitation for application because of hysteresis characteristics of PZT element in the filter, slow scan rate of the filter and the high cost of system. We proposed and experimented a multiple FBG sensor system using light emitting diode(LED) as a light source and adapting Code Division Multiplexing(CDM) method to separating out individual sensor signal. Output signals for a applied static and dynamic strain and crosstalk levels between sensor signals were measured. The price of the system is very loss and the response speed is very fast. Crosstalk levels between sensor signals below - 30 dB were demonstrated.

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Studies on the etching characteristics of PZT thin films using inductively coupled plasma (고밀도 플라즈마에 의한 PZT 박막의 식각특성 연구)

  • 안태현;김창일;장의구;서용진
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.13 no.3
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    • pp.188-192
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    • 2000
  • In this study PZT etching was performed using planar inductively coupled Ar/Cl$_2$/BCI$_3$ plasma. The etch rate of PZT film was 2450 $\AA$/min at Ar(20)/BCl$_3$(80) gas mixing ratio and substrate temperature of 8$0^{\circ}C$. X-ray photoelectron spectroscopy(XPS) analysis for films composition of etched PZT surface was utilized. The chemical bond of PbO is broken by ion bombardment and Cl radical, and the peak of metal Pb in a Pb 4f narrow scan begins to appear upon etching. As increasing additive BCl$_3$content the relative content of oxygen decreases rapidly in contrast with etch rate of PZT thin film. So we though that the etch rate of PZT thin film increased because abundant B and BCl radicals made volatile oxy-compound such as B$_{x}$/O$_{y}$ and/or BClO$_{x}$ bond. We achieved etch profile of about 80$^{\circ}$ at Ar(20)/BCl$_3$(80) gas mixing condition and substrate temperature of 8$0^{\circ}C$TEX>X>.

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Power Doppler ultrasound-guided sialography using the phenomenon of increased blood flow: A technical report

  • Oh, Song Hee;Seo, Yu-Kyeong;Kim, Gyu-Tae;Choi, Yong-Suk;Hwang, Eui-Hwan
    • Imaging Science in Dentistry
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    • v.49 no.4
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    • pp.301-306
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    • 2019
  • Purpose: This report presents a procedure for performing power Doppler ultrasound-guided sialography using the phenomenon of increased blood flow and illustrates its application to practical patient cases. Materials and Methods: The salivary gland was scanned using ultrasound equipment (GE LOGIQ5 Expert® device; GE Medical Systems, Milwaukee, WI, USA) to identify pathological findings related to the patient's chief complaint. To identify the orifice of the main duct, it should be cannulated using a lacrimal dilator. After inserting the catheter into the cannulated main duct, the position of the catheter within the duct was confirmed by ultrasound. A contrast agent was injected until the patient felt fullness, and ultrasound (B-mode) was used to confirm whether the contrast agent filled the main canal and secondary and tertiary ducts. Then, power Doppler ultrasound was performed to determine whether the salivary gland had increased blood flow. Results: In 2 cases in this report, a power Doppler ultrasound scan showed a significant increase in blood flow after contrast medium injection, which was not observed on a preoperative scan. Conclusion: Power Doppler ultrasound was found to be a simple, safe, and effective tool for real-time sialography monitoring.

Development of Digital 3D Real Object Duplication System and Process Technology (디지털 3차원 실물복제기 시스템 및 공정기술 개발)

  • Kim D.S.;An Y.J.;Lee W.H.;Choi B.O.;Chang M.H.;Baek Y.J.;Choi K.H.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.06a
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    • pp.732-737
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    • 2005
  • Distal 3D Real Object Duplication System(RODS) consists of 3D Scanner and Solid Freeform Fabrication System(SFFS). It is a device to make three-dimensional objects directly from the drawing or the scanning data. In this research, we developed an office type SFFS based on Three Dimensional Printing Process and a industrial SFFS using Dual Laser. An office type SFFS applied sliding mode control with sliding perturbation observer(SMCSPO) algorithm for control of this system. And we measured process variables about droplet diameter measurement and powder bed formation etc. through experiments. Also, in order to develop more elaborate and speedy system for large objects than existing SLS process, this study applies a new Selective Multi-Laser Sintering(SMLS) process and 3-axis dynamic Focusing Scanner for scanning large area instead of the existing $f\theta$ lens. In this process, the temperature has a great influence on sintering of the polymer. Also the laser parameters are considered like that laser beam power, scan speed, scan spacing. Now, this study is in progress to eveluate the effect of experimental parameters on the sintering process.

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Two Cases of Nontuberculous Mycobacterial Lung Disease in Heart Transplant Recipients (심장이식 환자에서 발생한 비결핵항산균 폐질환 2예)

  • Jo, Jung-Min;Shin, Mi-Seon;Kim, Joo-Hui;Kim, Min-Jung;Park, Hyun-Jung;Na, Hee-Kyung;Jo, Kyung-Uk;Kim, Jae-Joong;Shim, Tae-Sun
    • Tuberculosis and Respiratory Diseases
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    • v.69 no.3
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    • pp.201-206
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    • 2010
  • Nontuberculous mycobacterial (NTM) diseases are increasing worldwide. However NTM lung disease in organ transplant recipients has been rarely reported. Here, we report 2 cases of NTM lung disease in heart transplant recipients. A 37-year-old man, who had undergone a heart transplant one year previous, was admitted to hospital due to a cough. Chest CT scan showed multiple centrilobular nodules in both lower lungs. In his sputum, M. abscessus was repeatedly identified by rpoB gene analysis. The patient improved after treatment with clarithromycin, imipenem, and amikacin. An additional patient, a 53-year-old woman who had undergone a heart transplant 4 years prior and who suffered from bronchiectasis, was admitted because of purulent sputum. The patient's chest CT scan revealed aggravated bronchiectasis; M. intracellulare was isolated repeatedly in her sputum. Treatment was successfully completed with clarithromycin, ethambutol, and ciprofloxacin. NTM lung disease should be considered as a potential opportunistic infection in organ transplant recipients.

Quantitative Trait Loci Mapping for Porcine Backfat Thickness

  • Wu, X.L.;Lee, C.;Jiang, J.;Peng, Y.L.;Yan, H.F.;Yang, S.L.;Xiao, B.N.;Liu, X.C.;Shi, Q.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.15 no.7
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    • pp.932-937
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    • 2002
  • A partial genome scan using porcine microsatellites was carried out to detect quantitative trait loci (QTL) for backfat thickness (BFT) in a pig reference population. This population carried QTL on chromosomes 1, 13 and 18. The QTL on chromosome 1 was located between marker loci S0113 and SW1301. The QTL corresponded to very low density lipoprotein receptor gene (VLDLR) in location and in biological effects, suggesting that VLDLR might be a candidate gene. The QTL found on chromosome 13 was found between marker loci SWR1941 and SW864, but significance for the marker-trait association was inconsistent by using data with different generations. The QTL on chromosome 18 was discovered between markers S0062 and S0117, and it was in proximity of the regions where IGFBP3 and GHRHR were located. The porcine obese gene might be also a candidate gene for the QTL on chromosome 18. In order to understand genetic architecture of BFT better, fine mapping and positional comparative candidate gene analyses are necessary.

Detection of Imprinted Quantitative Trait Loci (QTL) for Growth Traits in Pigs

  • Lee, H.K.;Lee, S.S.;Kim, T.H.;Jeon, G.J.;Jung, H.W.;Shin, Y.S.;Han, J.Y.;Choi, B.H.;Cheong, I.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.8
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    • pp.1087-1092
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    • 2003
  • As an experimental reference population, crosses between Korean native pig and Landraces were established and information on growth traits was recorded. Animals were genotyped for 24 microsatellite markers covering chromosomes 2, 6, and 7 for partial-genome scan to identify chromosomal regions that have effects on growth traits. quantitative trait loci (QTL) effects were estimated using interval mapping by the regression method under the line cross models with a test for imprinting effects. For test of presence of QTL, chromosome-wide and single position significance thresholds were estimated by permutation test and normal significance threshold for the imprinting test were derived. For tests against the Mendelian model, additive and dominance coefficients were permuted within individuals. Thresholds (5% chromosome-wide) against the no-QTL model for the analyzed traits ranged from 4.57 to 4.99 for the Mendelian model and from 4.14 to 4.67 for the imprinting model, respectively. Partial-genome scan revealed significant evidence for 4 QTL affecting growth traits, and 2 out of the 4 QTLs were imprinted. This study demonstrated that testing for imprinting should become a standard procedure to unravel the genetic control of multi-factorial traits. The models and tests developed in this study allowed the detection and evaluation of imprinted QTL.

Quality Characteristics of White Pan Bread Using the Salt-Stressed Yeast Method (소금 스트레스 방법으로 처리한 이스트를 사용한 식빵의 품질특성)

  • Lee, Jun-Yul;Lee, Kwang-Suck
    • Culinary science and hospitality research
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    • v.18 no.4
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    • pp.266-276
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    • 2012
  • Salt, one of the main ingredients to make bread, functions differently according to environmental changes such as usage levels and methods. We examined the effects of yeast soaking time in about 8% salt solution on gas production and fermentation rate of dough and characteristics of white bread. Gas retention, related to gas production and fermentation rate, was the best at the 45 min soaking time. And pH of dough was appropriate to the fermentation in the range of 15 to 45 min of soaking time. Volume and specific volume of bread were best in 45 min soaking time(p<0.001), but the hardness of crumb texture analyzed with TA was the hardest among the samples(p<0.001). Brightness of color(L value) was significantly affected by soaking time(p<0.001), but b value was not considered. According to the preference test, the white pan bread made with 45 min soaking time in salt solution was preferred the most.

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