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Sample records for 64-detector row ct

  1. Whole tumour perfusion of peripheral lung carcinoma: evaluation with first-pass CT perfusion imaging at 64-detector row CT

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    Li, Y. [Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan (China); Yang, Z.-G. [Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan (China); National Key Laboratory of Biotherapy Center, West China Hospital, Sichuan University, Chengdu, Sichuan (China)], E-mail: yangzg1117@yahoo.com.cn; Chen, T.-w.; Deng, Y.-p.; Yu, J.-q.; Li, Z.-l. [Department of Radiology, West China Hospital, Sichuan University, Chengdu, Sichuan (China)

    2008-06-15

    Aim: To prospectively assess the feasibility of a whole-tumour perfusion technique using 64-detector row computed tomography (CT) and to analyse the variation of CT perfusion parameters in different histological types, sizes, and metastases in patients with peripheral lung carcinoma. Methods and materials: Ninety-seven pathologically proved peripheral lung carcinomas (less than 5 cm in largest diameter) underwent dynamic contrast-enhanced CT using a 64-detector row CT machine. Small amounts of iodinated contrast medium with a sharp bolus profile (50 ml, 6-7 ml/s), and 12 repeated fast acquisitions encompassing the entire tumour lesion were adopted to quantify perfusion of the whole-tumour during first-pass of contrast medium. Four kinetic parameters, including perfusion, peak enhancement intensity (PEI), time to peak (TTP), and blood volume (BV), were measured and statistically compared among different histological types, sizes, and metastases. Results: Mean values for perfusion, PEI, TTP, and BV of the 97 lung carcinomas were 57.5 {+-} 45.4 ml/min/ml (range 5.9-243 ml/min/ml), 53.4 {+-} 40.6 HU (range 10.3-234.4 HU), 34 {+-} 11 s (range 11-60 s), and 30.1 {+-} 21.7 ml/100 g (range 3.9-113.4 ml/100 g), respectively. No statistical differences were found between the histological types regarding the perfusion parameters (p > 0.05). Perfusion, PEI, and BV of stage T2 tumours were significantly lower than those of stage T1 tumours (all p < 0.05), whereas no statistically significant differences was found between other stages of tumours (all p > 0.05). Perfusion of the tumours with distant metastasis was significantly higher than that of the tumours without distant metastasis (p < 0.05), but there was no statistically significant difference between nodal metastasis positive and negative groups (p > 0.05). Conclusion: The present study of first-pass perfusion imaging using 64-detector row CT could provide a feasible method for assessment of whole-tumour perfusion. CT

  2. [Peripheral lung adenocarcinoma versus squamous cell carcinoma: evaluation with first-pass perfusion imaging using 64-detector row CT].

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    Li, Yuan; Yang, Zhigang; Chen, Tianwu; Yu, Jianqun; Deng, Yuping; Li, Zhenlin

    2009-04-01

    The aim of this study was to elucidate the characteristics of time attenuation curve and CT perfusion parameters for pulmonary adenocarcinomas and squamous cell carcinomas. 58 cases of pulmonary adenocarcinomas and 27 cases of squamous cell carcinomas underwent first pass CT perfusion imaging with 64-row MDCT. Data were analyzed using commercial software to generate time attenuation curve (TAC) and CT perfusion parameters, including perfusion, peak enhanced (PE), time to peak (TTP), and blood volume (BV). For TAC, there were 36.2% of type I and 63.8% of type II in adenocarcinomas, while there were 22.2% of type I and 77.8% of type II in squamous cell carcinomas. There was not significant difference (P>0.05). Perfusion, PE, TTP and BV of adenocarcinomas were 63.2 +/- 45.4 ml x min(-1) x ml(-1), 60.2 +/- 46.6 Hu, 34.8 +/- 10.2 s and 34.3 +/- 23.6 ml x 100 g(-1), respectively, while 54.3 +/- 50.2 ml x min(-1) x ml(-1), 48.5 +/- 34.9 Hu, 36.1 +/- 11.2 s and 27.6 +/- 21.7 ml x 100 g(-1), for squamous cell carcinoma, respectively. No significant differences were found between groups (P>0.05). No significant differences in TAC and CT perfusion parameters were found between adenocarcinomas and squamous cell carcinomas.

  3. Optimum CT reconstruction parameters for vascular and hepatocellular carcinoma models in a liver phantom with multi-level dynamic computed tomography with 64 detector rows: a basic study.

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    Murotani, Kazuhiro; Kazuhiro, Murotani; Kawai, Nobuyuki; Sato, Morio; Minamiguchi, Hiroki; Nakai, Motoki; Sonomura, Tetsuo; Hosokawa, Seiki; Nishioku, Tadayoshi

    2013-07-01

    We quantified to clarify the optimum factors for CT image reconstruction of an enhanced hepatocellular carcinoma (HCC) model in a liver phantom obtained by multi-level dynamic computed tomography (M-LDCT) with 64 detector rows. After M-LDCT scanning of a water phantom and an enhanced HCC model, we compared the standard deviation (SD, 1 ± SD), noise power spectrum (NPS) values, contrast-noise ratios (CNR), and the M-LDCT image among the reconstruction parameters, including the convolution kernel (FC11, FC13, and FC15), post-processing quantum filters (2D-Q00, 2D-Q01, and 2D-Q02) and slice thicknesses/slice intervals. The SD and NPS values were lowest with FC11 and 2D-Q02. The CNR values were highest with 2D-Q02. The M-LDCT image quality was highest with FC11 and 2D-Q02, and with slice thicknesses/slice intervals of 0.5 mm/0.5 mm and 0.5 mm/0.25 mm. The optimum factors were the FC11 convolution kernel, 2D-Q02 quantum filter, and 0.5 mm slice thickness/0.5 mm slice interval or less.

  4. Does Gadoxetic acid-enhanced 3.0T MRI in addition to 64-detector-row contrast-enhanced CT provide better diagnostic performance and change the therapeutic strategy for the preoperative evaluation of colorectal liver metastases?

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    Sofue, Keitaro [National Cancer Center Hospital, Division of Diagnostic Radiology, Tokyo (Japan); Kobe University, Department of Radiology, Graduate School of Medicine, Kobe (Japan); Tsurusaki, Masakatsu [National Cancer Center Hospital, Division of Diagnostic Radiology, Tokyo (Japan); Kinki University, Department of Radiology, Faculty of Medicine, Osakasayama, Osaka (Japan); Murakami, Takamichi [Kinki University, Department of Radiology, Faculty of Medicine, Osakasayama, Osaka (Japan); Onoe, Shunsuke [National Cancer Center Hospital, Department of Hepatobiliary and Pancreatic Surgery, Tokyo (Japan); Tokue, Hiroyuki; Shibamoto, Kentaro; Arai, Yasuaki [National Cancer Center Hospital, Division of Diagnostic Radiology, Tokyo (Japan); Sugimura, Kazuro [Kobe University, Department of Radiology, Graduate School of Medicine, Kobe (Japan)

    2014-10-15

    To compare diagnostic performance in the detection of colorectal liver metastases between 64-detector-row contrast-enhanced CT (CE-CT) alone and the combination of CE-CT and gadoxetic acid-enhanced MRI (EOB-MRI) at 3.0T, and to assess whether EOB-MRI in addition to CE-CT results in a change to initially planned operative strategy. A total of 39 patients (27 men, mean age 65 years) with 85 histopathologically confirmed liver metastases were included. At EOB-MRI, unenhanced (T1- and T2-weighted), dynamic, and hepatocyte-phase images were obtained. At CE-CT, four-phase dynamic contrast-enhanced images were obtained. One on-site reader and three off-site readers independently reviewed both CE-CT alone and the combination of CE-CT and EOB-MRI. Sensitivity, positive predictive value, and alternative free-response receiver operating characteristic (AFROC) method were calculated. Differences in therapeutic strategy before and after the EOB-MRI examination were also evaluated. Sensitivity and area under the AFROC curve with the combination of CE-CT and EOB-MRI were significantly superior to those with CE-CT alone. Changes in surgical therapy were documented in 13 of 39 patients. The combination of CE-CT and EOB-MRI may provide better diagnostic performance than CE-CT alone for the detection of colorectal liver metastases, and EOB-MRI in addition to CE-CT resulted in changes to the planned operative strategy in one-third of the patients. (orig.)

  5. Imaging the pericardium: appearances on ECG-gated 64-detector row cardiac computed tomography

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    O'Leary, S M; Williams, P L; Williams, M P; Edwards, A J; Roobottom, C A; Morgan-Hughes, G J; Manghat, N E

    2010-01-01

    Multidetector row computed tomography (MDCT) with its high spatial and temporal resolution has now become an established and complementary method for cardiac imaging. It can now be used reliably to exclude significant coronary artery disease and delineate complex coronary artery anomalies, and has become a valuable problem-solving tool. Our experience with MDCT imaging suggests that it is clinically useful for imaging the pericardium. It is important to be aware of the normal anatomy of the pericardium and not mistake normal variations for pathology. The pericardial recesses are visible in up to 44% of non-electrocardiogram (ECG)-gated MDCT images. Abnormalities of the pericardium can now be identified with increasing certainty on 64-detector row CT; they may be the key to diagnosis and therefore must not be overlooked. This educational review of the pericardium will cover different imaging techniques, with a significant emphasis on MDCT. We have a large research and clinical experience of ECG-gated cardiac CT and will demonstrate examples of pericardial recesses, their variations and a wide variety of pericardial abnormalities and systemic conditions affecting the pericardium. We give a brief relevant background of the conditions and reinforce the key imaging features. We aim to provide a pictorial demonstration of the wide variety of abnormalities of the pericardium and the pitfalls in the diagnosis of pericardial disease. PMID:20197434

  6. The frequency of intracranial arterial fenestrations: A study with 64-detector CT-angiography

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    Bayrak, Aylin Hasanefendioglu, E-mail: aylin_has@yahoo.com [Dicle University, School of Medicine, Radiology Department, Diyarbakir (Turkey); Senturk, Senem, E-mail: ssenturk@dicle.edu.tr [Dicle University, School of Medicine, Radiology Department, Diyarbakir (Turkey); Akay, Hatice Ozturkmen, E-mail: hozturkmen@gmail.com [Veni Vidi Hospital, Diyarbakir (Turkey); Ozmen, Cihan Akgul, E-mail: cihanakgul@dicle.edu.tr [Dicle University, School of Medicine, Radiology Department, Diyarbakir (Turkey); Bukte, Yasar, E-mail: ybukte@dicle.edu.tr [Dicle University, School of Medicine, Radiology Department, Diyarbakir (Turkey); Nazaroglu, Hasan, E-mail: hnazarog@dicle.edu.tr [Dicle University, School of Medicine, Radiology Department, Diyarbakir (Turkey)

    2011-03-15

    Fenestration is a vascular variation that begins with a common origin, then splits into two parallel luminal channels and rejoins distally. Potential association between anomalies of cerebral circulation and increased occurrence of aneurysm makes intracranial arterial fenestrations important. The planning of intracranial arterial interventions may be complicated if a fenestration occurs proximal to the site of intended treatment. This study is planned to determine the frequency of fenestrations on CT angiography and to search whether there is relationship between aneurysms and fenestrations. CT angiographies of 395 consecutive patients, performed by 64-detector CT, were retrospectively reviewed for aneurysms and fenestrations. Overall fenestration frequency, fenestration frequency in patients with and without aneurysm, and aneurysm frequency in patients with and without fenestration were searched. Demographic characteristics of patients were also compared. Overall fenestration frequency was 12.9%. Vertebrobasilar system (5.56%) and anterior communicating region (5.32%) were the two most frequent sites of fenestration. The rate of fenestrations was not significantly different between patients who had and did not have aneurysms. Mean age was significantly higher, and females were predominant in patients with aneurysms. However our results did not show significant difference in age and sex of patients with fenestrations. The frequency of fenestrations in this study is higher than in previously published radiological studies, suggesting that fenestrations are relatively common. There is no significant relationship between the frequency of aneurysms and fenestrations.

  7. In-Vitro Evaluation of Coronary Stents and 64-Detector-Row Computed Tomography Using a Newly Developed Model of Coronary Artery Stenosis

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    Schlosser, T.; Scheuermann, T.; Ulzheimer, S.; Mohrs, O.K.; Kuehling, M.; Albrecht, P.E.; Voigtlaender, T.; Barkhausen, J.; Schmermund, A. (Cardiovascular Center Bethanien (CCB), Frankfurt (DE))

    2008-02-15

    Background: Stent implantation is the predominant therapy for non-surgical myocardial revascularization in patients with coronary artery disease. However, despite substantial advances in multidetector computed tomography (MDCT) coronary imaging, a reliable detection of coronary in-stent restenosis is currently not possible. Purpose: To examine the ability of 64-detector-row CT to detect and to grade in-stent stenosis in coronary stents using a newly developed ex-vivo vessel phantom with a realistic CT density pattern, artificial stenosis, and a thorax phantom. Material and Methods: Four different stents (Liberte and Lunar ROX, Boston Scientific; Driver, Medtronic; Multi-Link Vision, Guidant) were examined. The stents were placed on a polymer tube with a diameter of 2.5, 3.0, 3.5, or 4.0 mm. Different degrees of stenosis (0%, 30%, 50%, 70-80%) were created inside the tube. For quantitative analysis, attenuation values were measured in the non-stenotic vessel outside the stent, in the non-stenotic vessel inside the stent, and in the stenotic area inside the stent. The grade of stenosis was visually assessed by two observers. Results: All stents led to artificial reduction of attenuation, the least degree of which was found in the Liberte stent (11.3+-10.2 HU) and the Multi-Link Vision stent (17.6+-17.9 HU; P 0.25). Overall, the non-stenotic vessel was correctly diagnosed in 55.5%, the low-grade stenosis in 58.3%, the intermediate stenosis in 63.8%, and the high-grade stenosis in 80.5%. In the 3.0-, 3.5-, and 4.0-mm vessels, in none of the cases was a non-stenotic or low-grade stenotic vessel misdiagnosed as intermediate or high-grade stenosis. The average deviation from the real grade of stenosis was 0.40 for the Liberte stent, 0.46 for the Lunar ROX stent, 0.45 for the Driver stent, and 0.58 for the Multi-Link Vision stent. Conclusion: Our ex-vivo data show that non-stenotic stents and low-grade in-stent stenosis can be reliably differentiated from intermediate and

  8. Comparison of 64-Detector CT Colonography and Conventional Colonoscopy in the Detection of Colorectal Lesions

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    Devir

    2016-01-01

    Full Text Available Background Colon cancer is a leading cause of morbidity and mortality in developed countries. The early detection of colorectal cancer using screening programs is important for managing early-stage colorectal cancers and polyps. Modalities that allow examination of the entire colon are conventional colonoscopy, double contrast barium enema examination and multi-detector computed tomography (MDCT colonography. Objectives To compare CT colonography and conventional colonoscopy results and to evaluate the accuracy of CT colonography for detecting colorectal lesions. Patients and Methods In a prospective study performed at Gastroenterology and Radiology Departments of Medical Faculty of Eskisehir Osmangazi University, CT colonography and colonoscopy results of 31 patients with family history of colorectal carcinoma, personal or family history of colorectal polyps, lower gastrointestinal tract bleeding, change in bowel habits, iron deficiency anemia and abdominal pain were compared. Regardless of the size, CT colonography and conventional colonoscopy findings for all the lesions were cross - tabulated and the sensitivity, specificity, and positive and negative predictive values were calculated. To assess the agreement between CT colonography and conventional colonoscopy examinations, the Kappa coefficient of agreementt was used. Statistical analysis was performed by SPSS ver 15.0. Results Regardless of the size, MDCT colonography showed 83% sensitivity and 95% specificity, with a positive predictive value of 95% and a negative predictive value of 83% for the detection of colorectal polyps and masses. MDCT colonography displayed 92% sensitivity and 95% specificity, with a positive predictive value of 92% and a negative predictive value of 95% for polyps ≥ 10 mm. For polyps between 6mm and 9 mm, MDCT colonography displayed 75% sensitivity and 100% specificity, with a positive predictive value of 100% and a negative predictive value of 90%. For polyps

  9. Evaluation of Enteroneovesical Fistula by 64-Detector CT Enterography: A Case Report

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    Algin, Oktay; Metin, Melike Rusen; Karaoglanoglu, Mustafa

    2015-01-01

    Enterovesical fistula is an abnormal communication between the bladder and the intestine. The accurate localization of leakage is important for accurate treatment planning. Some imaging techniques can not demonstrate the fistula; therefore, choosing the appropriate imaging technique is necessary. CT enterography (CTE) is a new technique for evaluation of the small bowel and the entire abdomen. CTE examination with multi-detector CT (MDCT) enables us to get excellent quality reformatted images with high spatial resolution. We report a patient with neobladder and enteroneovesical fistula. We showed the exact location of the fistula and its’ association with the bowels and neobladder by CTE. The aim of this report is to show that CTE can be a new and effective modality in the detection of enteroneovesical fistulas and to discuss the efficacy of CTE in the detection and evaluation of enterovesical fistula referring to the literature. In conclusion, CTE may be a useful, sensitive, effective, and non-invasive technique for the evaluation of enteroneovesical fistula, leakage from the anastomose sides, and other extraintestinal complications such as urinary tract obstruction or abscess formation. PMID:26060558

  10. Desmoid Tumor Associated With Familial Adenomatous Polyposis: Evaluation With 64-Detector CT Enterography

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    Oktay Algin

    2012-03-01

    Full Text Available Desmoid tumors (DTs are benign tumors which are not seen very often, and most of the radiologists and clinicians do not know the characteristics of them very well. Correct and early diagnosis of DTs is important for decreasing mortality and morbidity. Computed tomography enterography (CTE is a new modality for small bowel imaging which combines the improved spatial and temporal resolution of multidetector computed tomography (CT with large volumes of ingested enteric contrast material to permit evaluation of the small bowel wall and lumen and also the entire abdomen. We report a familial adenomatous polyposis (FAP patient with localized mesentery and abdominal wall DTs. We showed the exact location of the DTs and their relation with the small bowel by CTE. In conclusion, CTE is a useful technique for DT localization, the degree of extension and invasion to local structures, presence of partial and complete small bowel obstruction, and the relationship of the tumors with vasculature and whether ischemia ha s occurred as a result or not.

  11. MR angiography with parallel acquisition for assessment of the visceral arteries: comparison with conventional MR angiography and 64-detector-row computed tomography

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    Sutter, Reto [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Cantonal Hospital Winterthur, Department of Radiology, Winterthur (Switzerland); Heilmaier, Christina [University Hospital Essen, Department of Diagnostic and Interventional Radiology and Neuroradiology, Essen (Germany); Lutz, Amelie M.; Willmann, Juergen K. [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Stanford University School of Medicine, Department of Radiology, Stanford, CA (United States); Weishaupt, Dominik [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Hospital Triemli, Department of Radiology, Zurich (Switzerland); Seifert, Burkhardt [University of Zurich, Biostatistics Unit, Institute of Social and Preventive Medicine, Zurich (Switzerland)

    2009-11-15

    The purpose of the study was to retrospectively compare three-dimensional gadolinium-enhanced magnetic resonance angiography (conventional MRA) with MRA accelerated by a parallel acquisition technique (fast MRA) for the assessment of visceral arteries, using 64-detector-row computed tomography angiography (MDCTA) as the reference standard. Eighteen patients underwent fast MRA (imaging time 17 s), conventional MRA (29 s) and MDCTA of the abdomen and pelvis. Two independent readers assessed subjective image quality and the presence of arterial stenosis. Data were analysed on per-patient and per-segment bases. Fast MRA yielded better subjective image quality in all segments compared with conventional MRA (P = 0.012 for reader 1, P = 0.055 for reader 2) because of fewer motion-induced artefacts. Sensitivity and specificity of fast MRA for the detection of arterial stenosis were 100% for both readers. Sensitivity of conventional MRA was 89% for both readers, and specificity was 100% (reader 1) and 99% (reader 2). Differences in sensitivity between the two types of MRA were not significant for either reader. Interobserver agreement for the detection of arterial stenosis was excellent for fast ({kappa} = 1.00) and good for conventional MRA ({kappa} = 0.76). Thus, subjective image quality of visceral arteries remains good on fast MRA compared with conventional MRA, and the two techniques do not differ substantially in the grading of arterial stenosis, despite the markedly reduced acquisition time of fast MRA. (orig.)

  12. Peripheral Lung Adenocarcinoma versus Squamous Cell Carcinoma: Evaluation with First-pass Perfusion Imaging Using 64-detector Row CT%周围型肺腺癌与鳞癌64层螺旋CT首过时间灌注特征对比研究

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    李媛; 杨志刚; 陈天武; 余建群; 邓瑜萍; 李真林

    2009-01-01

    明确周围型肺腺癌与鳞癌首过时间CT灌注成像时间密度曲线及灌注值特征.对58例周围型肺腺癌和27例周围型肺鳞癌行64层螺旋CT首过时间灌注扫描,测定和评价病灶时间密度曲线(Time attenuation curve, TAC)、灌注值(perfusion)、强化峰值(PEI)、对比剂到达峰值时间(TTP)及血容量(BV)等灌注参数.周围型腺癌TACⅠ型占36.2%,Ⅱ型占63.8%;而周围型鳞癌TACⅠ型占22.2%,Ⅱ型占77.8%,两者构成比无显著差异(P>0.05).58例周围型腺癌首过时间CT perfusion值为63.2±45.4 ml·min-1·ml-1,PE值为60.2±46.6 Hu,TTP值为34.8±10.2 s,BV值为34.3±23.6 ml·100 g-1;27例周围型腺癌首过时间CT perfusion值为54.3±50.2 ml·min-1·ml-1,PE值为48.5±34.9 Hu,TTP值为36.1±11.2 s,BV值为27.6±21.7 ml·100g-1,两组间CT灌注值的差异均无统计学意义(P>0.05).表明周围型肺腺癌和鳞癌在TAC表现和CT灌注值均无显著差别.

  13. Comparison of the aortic valve calcium content in the bicuspid and tricuspid stenotic aortic valve using non-enhanced 64-detector-row-computed tomography with prospective ECG-triggering

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    Ferda, Jiri [Department of Radiology, Charles University Hospital Plzen, Alej Svobody 80, CZ-306 40 Plzen (Czech Republic)], E-mail: ferda@fnplzen.cz; Linhartova, Katerina [Department of Cardiology, Cardiovascular Center, Charles University Hospital Motol, V Uvalu 84, Prague (Czech Republic); Kreuzberg, Boris [Department of Radiology, Charles University Hospital Plzen, Alej Svobody 80, CZ-306 40 Plzen (Czech Republic)

    2008-12-15

    Purpose: The aim of our study was to compare the calcium content measured by non-enhanced multidetector-row-computed tomography (MDCT) between patients with significant stenosis of bicuspid (BAV) and tricuspid aortic valve (TAV). Another aim of our study was to assess the accuracy of the non-enhanced MDCT to distinguish BAV and TAV based on the calcified plaque morphology, and to compare the results with the transesophageal echocardiography. Subjects and methods: A retrospective analysis of prospectively collected data was performed. Consecutive patients with symptomatic aortic stenosis (AS) admitted to hospital for evaluation before valve surgery underwent clinical evaluation, transthoracic and transesophageal echocardiography, and non-enhanced examination with the 64-detector-row CT using prospective ECG triggering with data acquisition in diastolic phase. The data acquisition started at 55% of the R-R interval. The patients were examined in the supine position in mild inspiration. Data were evaluated using dedicated software for calcium scoring, the volume of calcifications and calcium content were obtained. Results: Thirty-seven patients (20 males, age 48-83 years) were enrolled. BAV was present in 13 patients, TAV in 24 patients. The calcium score in patients with severe AS (mean gradient >50 mmHg) was higher than in those with moderate AS (1123 {+-} 616 mg versus 634 {+-} 475, P = 0.011). Significant correlation between the calcium scores and transaortic gradients was found (r = 0.53, P = 0.002). The patients with BAV did not differ significantly from those with TAV in the AS severity (58 {+-} 13 versus 53 {+-} 20 mmHg), nor in the valve calcium score (1168 {+-} 717 versus 795 {+-} 530 mg, P = 0.093). The overall sensitivity to detect BAV in patients with calcified severe AS was 0.923 (12/13) and specificity 0.958 (23/24). The overall accuracy was 0.945 (35/37). Conclusion: We observed higher calcium score in patients with severe AS than with moderate AS

  14. Estimation of organ-absorbed radiation doses during 64-detector CT coronary angiography using different acquisition techniques and heart rates: a phantom study

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    Matsubara, Kosuke; Koshida, Kichiro; Kawashima, Hiroko (Dept. of Quantum Medical Technology, Faculty of Health Sciences, Kanazawa Univ., Kanazawa (Japan)), email: matsuk@mhs.mp.kanazawa-u.ac.jp; Noto, Kimiya; Takata, Tadanori; Yamamoto, Tomoyuki (Dept. of Radiological Technology, Kanazawa Univ. Hospital, Kanazawa (Japan)); Shimono, Tetsunori (Dept. of Radiology, Hoshigaoka Koseinenkin Hospital, Hirakata (Japan)); Matsui, Osamu (Dept. of Radiology, Faculty of Medicine, Kanazawa Univ., Kanazawa (Japan))

    2011-07-15

    Background: Though appropriate image acquisition parameters allow an effective dose below 1 mSv for CT coronary angiography (CTCA) performed with the latest dual-source CT scanners, a single-source 64-detector CT procedure results in a significant radiation dose due to its technical limitations. Therefore, estimating the radiation doses absorbed by an organ during 64-detector CTCA is important. Purpose: To estimate the radiation doses absorbed by organs located in the chest region during 64-detector CTCA using different acquisition techniques and heart rates. Material and Methods: Absorbed doses for breast, heart, lung, red bone marrow, thymus, and skin were evaluated using an anthropomorphic phantom and radiophotoluminescence glass dosimeters (RPLDs). Electrocardiogram (ECG)-gated helical and ECG-triggered non-helical acquisitions were performed by applying a simulated heart rate of 60 beats per minute (bpm) and ECG-gated helical acquisitions using ECG modulation (ECGM) of the tube current were performed by applying simulated heart rates of 40, 60, and 90 bpm after placing RPLDs on the anatomic location of each organ. The absorbed dose for each organ was calculated by multiplying the calibrated mean dose values of RPLDs with the mass energy coefficient ratio. Results: For all acquisitions, the highest absorbed dose was observed for the heart. When the helical and non-helical acquisitions were performed by applying a simulated heart rate of 60 bpm, the absorbed doses for heart were 215.5, 202.2, and 66.8 mGy for helical, helical with ECGM, and non-helical acquisitions, respectively. When the helical acquisitions using ECGM were performed by applying simulated heart rates of 40, 60, and 90 bpm, the absorbed doses for heart were 178.6, 139.1, and 159.3 mGy, respectively. Conclusion: ECG-triggered non-helical acquisition is recommended to reduce the radiation dose. Also, controlling the patients' heart rate appropriately during ECG-gated helical acquisition with

  15. Experience with volumetric (320 rows) pediatric CT

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    Sorantin, E., E-mail: erich.sorantin@medunigraz.at [Division of Pediatric Radiology, Department of Radiology, Medical University Graz (Austria); Riccabona, M. [Division of Pediatric Radiology, Department of Radiology, Medical University Graz (Austria); Stücklschweiger, G.; Guss, H. [Competence Centre for Medical Physics and Radiation Protection, Univ.-Hospital Graz (Austria); Fotter, R. [Division of Pediatric Radiology, Department of Radiology, Medical University Graz (Austria)

    2013-07-15

    The introduction of helical computer tomography (CT) and further progress to multi-slice CT enabled new applications. Most recent developments like the 320-row detector facilitate volume CT, which avoids the over-beaming effect of helical scanning. The 320-row multi-slice detector CT (MDCT) is based on a 16 cm detector; a special acquisition mode allows reconstructing 640 slices from these 16 cm. The shortest tube rotation time is in cardiac mode 0.35 s, otherwise 0.4 s and 0.5 s used. At 0.5 s the machine already reaches the maximum numbers of sub-second projections. Scan modes can be volume, helical and single slice mode. For image acquisition all dose savings technologies like variable tube position for scano-view, active collimation, automated exposure control, bolus and ECG tracking are available. Additionally special acquisition and post-processing techniques like head and body perfusion CT are ready for use on the console. For image reconstruction properties like filtered back projection as well as the latest development of iterative algorithms, an appropriate number of kernels and multi-planar reconstruction in all directions from the volume data at every increment are available. Volume CT allows sub second scanning of 16 cm z-coverage which, however, makes administration of intravenous contrast medium to “hit or miss” event. The aim of this paper is to present the application of volume CT to body scanning in children. Representative examples of neck, cardiac and skeletal investigations are given.

  16. CT paging arteriography with a multidetector-row CT. Advantages in splanchnic arterial imaging

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    Kobayashi, Seiji [Keio Univ., Tokyo (Japan). School of Medicine

    1999-11-01

    The purpose of this study is to assess the utility of CT paging arteriography with a multidetector-row CT as a replacement for conventional angiography in the evaluation of splanchnic arterial anomalies. Sixty-three patients underwent CT paging arteriography with a multidetector-row CT. In the 56 patients with conventional angiographic correlation, there was only one minor disagreement with CT paging arteriography. In the 7 patients who underwent IVDSA (intra venous digital subtraction angiography), CT paging arteriography defined four hepatic arterial anomalies which could not be depicted by IVDSA. In conclusion, CT paging arteriography provides noninvasive means to identify splanchnic arterial anomalies. (author)

  17. Diagnostic Value of 64-Detector Spiral CT Angiography for Dissecting Aneurysm of Aorta%64层螺旋CT血管造影在主动脉夹层动脉瘤中的应用

    Institute of Scientific and Technical Information of China (English)

    章绪辉; 全显跃; 俞志坚; 黄志平

    2011-01-01

    目的:评价64层螺旋CT血管造影在主动脉夹层动脉瘤中的应用价值。材料与方法:收集主动脉夹层动脉瘤CT血管造影41例,原始横断面图像结合MPR、MIP、VR进行图像分析。结果:原始横断面图像能明确主动脉夹层动脉瘤的诊断,能清晰显示真假腔41例(100%),分离移位的内膜片41例(100%)、内膜破口37例(90.2%)、主动脉分支受累21例(51.2%)、假腔内血栓形成27例(65.9%);MPR、MIP及VR能显示病变的空间情况,对原始横断面图像是很好的补充。对横断面图像较难显示小的内膜破裂口,MPR图像能清楚显示。MIP及VR可以立体、直观地显示主动脉夹层情况。结论:64层螺旋CT血管造影能明确诊断主动脉夹层动脉瘤,具有快速、准确、无创的特点,是诊断主动脉夹层动脉瘤的首选检查方法。%Objective:To evaluate clinical application value of 64-detector spiral CT angiography for dissecting aneurysm of aorta(ADA).Material and methods:CT angiography was performed in 41 cases with ADA,Original axial images combined with MPR,MIP and VR were analyzed.Results:The original axial images can diagnose ADA definitely and clearly show true lumen and false lumen(100%),intimal flap(100%),entry of intimal tear(90.2%),the involvement of branches of aortic(51.2%) and thrombosed false lumen(65.9%),The images of MPR,MIP and VR can show space conditions of aorta and is a very good supplement to the original axial images.The images of MPR can clearly show those entries of intimal tear that the axial images show difficultly,The images of MIP and VR can show the condition of ADA spatially and intuitively.Conclusion:64-detector spiral CT angiography can diagnose ADA definitely and are accurate,quick and non-trauma,so the examination may be as the first choice method in diagnosis of ADA.

  18. Coronary Artery Stent Evaluation Using a Vascular Model at 64-Detector Row CT: Comparison between Prospective and Retrospective ECG-Gated Axial Scans

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Shigeru; Furui, Shigeru; Kaminaga, Tatsuro; Miyazawa, Akiyoshi; Ueno, Yasunari; Konno, Kumiko [Teikyo University School of Medicine, Tokyo (Japan); Kuwahara, Sadatoshi; Mehta, Dhruv [Philips Electronics Japan, Ltd. Medical Systems, Tokyo (Japan)

    2009-06-15

    We wanted to evaluate the performance of prospective electrocardiogram (ECG)-gated axial scans for assessing coronary stents as compared with retrospective ECG-gated helical scans. As for a vascular model of the coronary artery, a tube of approximately 2.5-mm inner diameter was adopted and as for stents, three (Bx-Velocity, Express2, and Micro Driver) different kinds of stents were inserted into the tube. Both patent and stenotic models of coronary artery were made by instillating different attenuation (396 vs. 79 Hounsfield unit [HU]) of contrast medium within the tube in tube model. The models were scanned with two types of scan methods with a simulated ECG of 60 beats per minute and using display field of views (FOVs) of 9 and 18 cm. We evaluated the in-stent stenosis visually, and we measured the attenuation values and the diameter of the patent stent lumen. The visualization of the stent lumen of the vascular models was improved with using the prospective ECG-gated axial scans and a 9-cm FOV. The inner diameters of the vascular models were underestimated with mean measurement errors of -1.10 to -1.36 mm. The measurement errors were smaller with using the prospective ECG-gated axial scans (Bx-Velocity and Express2, p < 0.0001; Micro Driver, p = 0.0004) and a 9-cm FOV (all stents: p < 0.0001), as compared with the other conditions, respectively. The luminal attenuation value was overestimated in each condition. For the luminal attenuation measurement, the use of prospective ECG-gated axial scans provided less measurement error compared with the retrospective ECG-gated helical scans (all stents: p < 0.0001), and the use of a 9-cm FOV tended to decrease the measurement error. The visualization of coronary stents is improved by the use of prospective ECG-gated axial scans and using a small FOV with reduced blooming artifacts and increased spatial resolution.

  19. Esophageal injuries: Spectrum of multidetector row CT findings

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    Lutio di Castelguidone, Elisabetta de [Department of Radiology, I.N.T., IRCCS Fondazione G. Pascale, Via M. Semmola, I-80131 Naples (Italy)]. E-mail: e.delutio@virgilio.it; Merola, Stefanella [Department of Diagnostic Imaging, ' A. Cardarelli' Hospital, I-80131 Naples (Italy); Pinto, Antonio [Department of Diagnostic Imaging, ' A. Cardarelli' Hospital, I-80131 Naples (Italy); Raissaki, Maria [Department of Radiology, University Hospital of Iraklion, University of Crete Medical School, P.O. Box 1352, 711 10 Iraklion Crete (Greece); Gagliardi, Nicola [Department of Diagnostic Imaging, ' A. Cardarelli' Hospital, I-80131 Naples (Italy); Romano, Luigia [Department of Diagnostic Imaging, ' A. Cardarelli' Hospital, I-80131 Naples (Italy)

    2006-09-15

    Background: Aim of this study is to illustrate the multidetector row computed tomographic findings related to oesophageal injuries and their significance for therapeutic decisions. Method: From April 2002 to April 2005 we studied 16 patients with suspected oesophageal injury. Ten patients underwent standard chest radiograph, while five patients with suspected foreign body ingestion were submitted to cervical plain film and gastrografin swallow study. All 16 patients underwent multidetector row CT examination. Results: In six patients with cervical, thoracic and abdominal trauma, CT showed the presence of thoracic traumatic lesions and findings suggestive of perforation of the oesophagus. In five patients with foreign body ingestion cervical radiography was positive in only one case, while CT showed the presence of a foreign body in all cases. In three patients with post-intubation complications, CT showed the presence of perioesophageal fluid collection containing small gas bubbles in two cases and an oesophageal-aortic fistula in one case. In the remaining two patients with suspected spontaneous oesophageal perforation, CT demonstrated an oesophageal wall oedema and thickening in one case, and oesophageal fluid distension with perioesophageal small bubbles gas and fluid in the second case. Conclusion: Oesophageal injuries, when complicated with perforation, constitute a life-threatening condition. Knowledge of the CT signs of oesophageal injuries has important implications for the role of imaging at the time of initial diagnosis.

  20. Multi-Detector row CT urography on a 16-row CT scanner in the evaluation of urothelial tumors

    Energy Technology Data Exchange (ETDEWEB)

    Tsili, A.C. [University Hospital of Ioannina, Department of Clinical Radiology, Ioannina (Greece); University of Ioannina, Medical School, Ioannina (Greece); Efremidis, S.C.; Tsampoulas, C. [University Hospital of Ioannina, Department of Clinical Radiology, Ioannina (Greece); Kalef-Ezra, J. [University Hospital of Ioannina, Department of Medical Physics, Ioannina (Greece); Giannakis, D.; Sofikitis, N. [University Hospital of Ioannina, Department of Urology, Ioannina (Greece); Alamanos, Y. [University Hospital of Ioannina, Department of Hygiene and Public Health, Ioannina (Greece)

    2007-04-15

    The purpose of this study was to assess the role of multi-detector row CT urography (MDCTU), on a 16-row CT scanner in the evaluation of patients with painless hematuria, with emphasis placed in the detection of urothelial tumors. We retrospectively reviewed the MDCT urographies of 75 patients, referred for painless hematuria. The CT protocol included unenhanced images, obtained with a detector configuration of 16 x 1.5 mm and pitch of 1.2, nephrographic and excretory-phase images, obtained with a detector collimation of 16 x 0.75 mm and pitch of 1.2. Axial and coronal reformatted images were evaluated. Three-dimensional reformation of the excretory-phase images was performed using the volume-rendering technique. The standard of reference included clinical and imaging follow-up, cystoscopic, surgical and histologic findings. In 55 (73%) of 75 patients, the cause of hematuria was identified on MDCTU; the most common cause was urothelial cancer, including seven tumors with a diameter equal or smaller than 0.5 cm in diameter. Sixteen-row MDCTU provided satisfactory results in the investigation of patients with painless hematuria. The main advantage of the technique is its ability to detect uroepithelial malignancies. (orig.)

  1. Multidetector-row CT with a 64-row amorphous silicon flat panel detector

    Science.gov (United States)

    Shapiro, Edward G.; Colbeth, Richard E.; Daley, Earl T.; Job, Isaias D.; Mollov, Ivan P.; Mollov, Todor I.; Pavkovich, John M.; Roos, Pieter G.; Star-Lack, Josh M.; Tognina, Carlo A.

    2007-03-01

    A unique 64-row flat panel (FP) detector has been developed for sub-second multidetector-row CT (MDCT). The intent was to explore the image quality achievable with relatively inexpensive amorphous silicon (a-Si) compared to existing diagnostic scanners with discrete crystalline diode detectors. The FP MDCT system is a bench-top design that consists of three FP modules. Each module uses a 30 cm x 3.3 cm a-Si array with 576 x 64 photodiodes. The photodiodes are 0.52 mm x 0.52 mm, which allows for about twice the spatial resolution of most commercial MDCT scanners. The modules are arranged in an overlapping geometry, which is sufficient to provide a full-fan 48 cm diameter scan. Scans were obtained with various detachable scintillators, e.g. ceramic Gd IIO IIS, particle-in-binder Gd IIO IIS:Tb and columnar CsI:Tl. Scan quality was evaluated with a Catphan-500 performance phantom and anthropomorphic phantoms. The FP MDCT scans demonstrate nearly equivalent performance scans to a commercial 16-slice MDCT scanner at comparable 10 - 20 mGy/100mAs doses. Thus far, a high contrast resolution of 15 lp/cm and a low contrast resolution of 5 mm @ 0.3 % have been achieved on 1 second scans. Sub-second scans have been achieved with partial rotations. Since the future direction of MDCT appears to be in acquiring single organ coverage per scan, future efforts are planned for increasing the number of detector rows beyond the current 64- rows.

  2. Sacroiliitis in Ankylosing Spondylitis: Comparison with Multidetector Row CT and Plain Radiography

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Ji Youn; Joo, Kyung Bin; Choi, Byeong Kyoo; Ryu, Jeong Ah; Kim, Tae Hwan; Choi, Woo Jung [Hanyang University Hospital, Seoul (Korea, Republic of)

    2009-03-15

    The objective of our study was to compare multidetector row CT and the plain radiographs for making the diagnosis and grading the sacroiliitis that accompanies ankylosing spondylitis. We wanted to determine the role of multidetector row CT for the evaluation of the sacroilitis in patients with ankylosing spondylitis. One hundred ninety two patients with clinically suspected ankylosing spondylitis were evaluated by conventional radiography and multidetector row CT. Two musculoskeletal radiologists retrospectively analyzed the images, and they graded the sacroiliitis using the modified New York Criteria. Multidetector row CT demonstrated a significantly higher sensitivity (74.5%, 83.3%) than did plain radiography (59.9%, 66.7%) for detecting early sacroiliitis (p<0.05). Multidetector row CT showed a higher grade of sacroiliitis in 114 and 127 of 384 sacroiliac joints. Performing multidetector row CT rather than plain radiography for making the diagnoses of accompanying ankylosing spondylitis allows an early start of treatment with a subsequently improved prognosis

  3. Cancerogenesis Risks between 64 and 320 Row Detector CT for Coronary CTA Screening

    Directory of Open Access Journals (Sweden)

    Atif N Khan

    2014-01-01

    Full Text Available Objectives: This study compares cancerogenesis risks posed by the 64 row detector and the 320 row detector computed tomography scanners used during coronary computed tomography angiography (CCTA following decennial screening guidelines. Material and Methods: Data of the radiation absorbed after CCTA by lung, thyroid, and female breast in patients between 50 and 70 years of age obtained from prior published literature for the 64 row CT scanner were compared with data from our study using 320 row detector CT scanner. Data from the 64 row and the 320 row detector CT scanners was used to determine lifetime attributable risks (LAR of cancer based on the biological effects of ionizing radiation (BEIR VII report. Results: The relative reduction of LAR (% for 50-, 60-, and 70-year-old patients undergoing scanning with the 320 row detector CT scanner was 30% lower for lung, and more than 50% lower for female breast when compared with results from 64 row detector CT scanner. The use of 320 row detector CT would result in a combined cumulative cancer incidence of less than 1/500 for breast in women and less than 1/1000 for lung in men; By comparison, this is much lower than other more common risk factors: 16-fold for lung cancer in persistent smokers, 2-fold for breast cancer with a first degree family member history of breast cancer, and 10-fold for thyroid cancer with a family member with thyroid cancer. Decennial screening would benefit at least 355,000 patients from sudden cardiac death each year, 94% of whom have significant coronary artery disease, with at least one stenosis >75%. LAR for thyroid cancer was negligible for both scanners. Conclusion: Lung and female breast LAR reductions with 320 row detector compared with 64 row detector CT are substantial, and the benefits would outweigh increased cancer risks with decennial screening in the age group of 50-70 years.

  4. Multidetector row-CT in evaluation of living renal donors

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ji-qing; HU Xiao-peng; WANG Wei; LI Xiao-bei; YIN Hang; ZHANG Xiao-dong

    2010-01-01

    Background Multidetector-row CT (MDCT) has been evolving to the standard evaluating method of potential living donor in most centers, and can provide excellent details for selecting candidates and determining surgical technique.This study aimed to assess the value of MDCT in evaluation of the anatomy of living kidney donors and to reveal the prevalence of renal vascular variations in a Chinese population.Methods One hundred and four potential donors underwent MDCT and the data sets were post-processed for reformatted images with various techniques, such as maximum intensity projection (MIP), a volume-rendering technique (VR), and multiplanar reformation (MPR). Donor nephrectomies were performed on 97 candidates after MDCT evaluation with the findings during surgery constituting the standard of reference. Resulting MDCT images were compared with actual anatomy found during surgery. Results The MDCT images accurately displayed the anatomic structure of the main renal arteries and veins as well as the upper ureters, except in one case with horseshoe kidney. The prevalence of accessory arteries revealed in images was 27.2% (28/103) and early branching was found in 12.6% (13/103). Compared with findings during surgery, the detection of accessory arteries in MDCT images was 85.7% (6/7), and the detection of larger accessory arteries (>1.5 mm in diameter) was 100%. Detection of early branching was 100%.Conclusion MDCT helps accurately evaluate the renal anatomy of potential donors thus facilitating the planning of surgery.

  5. Comparison of 64-row and 16-row multidetector CT in the perfusion CT evaluation of acute ischemic stroke patients receiving intravenous thrombolytic therapy

    Energy Technology Data Exchange (ETDEWEB)

    Sillanpaa, Niko; Dastidar, Prasun; Soimakallio, Seppo [Tampere University Hospital, Medical Imaging Centre, PL 2000, Tampere (Finland); Rusanen, Harri [Oulu University Hospital, Department of Neurology, Oulu (Finland); Saarinen, Jukka T. [Tampere University Hospital, Department of Neurology, Tampere (Finland)

    2012-09-15

    Perfusion computed tomography (PCT) is increasingly performed in multimodal CT evaluation of acute ischemic stroke. We compared the technical quality of perfusion studies performed with a 16-row and a 64-row scanner and analyzed the differences between the scanners in their ability to detect perfusion defects. We analyzed retrospectively the clinical and imaging data of 140 consecutive acute (<3 h) stroke patients who underwent multimodal CT evaluation and received intravenous rtPA. Alberta Stroke Program Early CT Score (ASPECTS) was assigned to PCT maps. Clinical and imaging parameters were compared between the two scanners. There were more motion artifacts in the 16-row studies (p = 0.04), and the analysis software was able to completely correct significantly fewer of these (p < 0.001). Both ASPECTS levels were optimally covered in only 29% of the 16-row studies, whereas in the 64-row studies, both levels were invariably optimally visualized (p < 0.001). This significantly decreased the sensitivity of the 16-row scanner to detect perfusion defects in the upper ASPECTS level (p = 0.02). The 64-row scanner was able to detect more perfusion defects that were located entirely outside the ASPECTS regions (p = 0.03). There was no significant difference in the 3-month functional outcome. The 16-row scanner suffered from limited anatomic coverage that decreased the sensitivity to detect perfusion defects in the cranial parts of the middle cerebral artery region. The 16-row studies had poorer technical quality that was in part attributable to higher sampling frequency and smaller slice thickness making the imaging more sensitive to small-scale movement of the patient. (orig.)

  6. Evaluation of radiation dose in 64-row whole-body CT of multiple injured patients compared to 4-row CT; Evaluation der Strahlendosis bei Polytrauma-CT-Untersuchungen eines 64-Zeilen-CT im Vergleich zur 4-Zeilen-CT

    Energy Technology Data Exchange (ETDEWEB)

    Harrieder, A.; Geyer, L.L.; Koerner, M.; Deak, Z.; Wirth, S.; Reiser, M.; Linsenmaier, U. [Ludwig-Maximilians-Univ. Muenchen (Germany). Inst. fuer Klinische Radiologie

    2012-05-15

    Purpose: To evaluate radiation exposure in whole-body CT (WBCT) of multiple injured patients comparing 4-row multidetector computed tomography (MDCT) to 64-row MDCT. Materials and Methods: 200 WBCT studies were retrospectively evaluated: 92 4-row MDCT scans and 108 64-row MDCT scans. Each CT protocol was optimized for the particular CT system. The scan length, CT dose index (CTDI), and dose length product (DLP) were recorded and analyzed for radiation exposure. The mean effective dose was estimated based on conversion factors. Student's t-test was used for statistical analysis. Results: The mean CTDI{sub vol} values (mGy) of the thorax and abdomen were significantly reduced with 64-row MDCT (10.2 {+-} 2.5 vs. 11.4 {+-} 1.4, p < 0.001; 14.2 {+-} 3.7 vs. 16.1 {+-} 1.7, p < 0.001). The DLP values (mGy x cm) of the head and thorax were significantly increased with 64-row MDCT (1305.9 {+-} 201.1 vs. 849.8 {+-} 90.9, p < 0,001; 504.4 {+-} 134.4 vs. 471.5 {+-} 74.1, p = 0.030). The scan lengths (mm) were significantly increased with 64-row MDCT: head 223.6 {+-} 35.8 vs. 155.5 {+-} 12.3 (p < 0.001), thorax 427.4 {+-} 44.5 vs. 388.3 {+-} 57.5 (p < 0.001), abdomen 520.3 {+-} 50.2 vs. 490.8 {+-} 51.6 (p < 0.001). The estimated mean effective doses (mSv) were 22.4 {+-} 2.6 (4-row MDCT) and 24.1 {+-} 4.6 (64-row MDCT; p = 0.001), resulting in a percentage increase of 8 %. Conclusion: The radiation dose per slice of the thorax and abdomen can be significantly decreased by using 64-row MDCT. Due to the technical advances of modern 64-row MDCT systems, the scan field can be adapted to the clinical demands and, if necessary, enlarged without time loss. As a result, the estimated mean effective dose might be increased in WBCT. (orig.)

  7. Acute gastrointestinal bleeding: detection of source and etiology with multi-detector-row CT

    Energy Technology Data Exchange (ETDEWEB)

    Scheffel, Hans; Pfammatter, Thomas; Marincek, Borut; Alkadhi, Hatem [University Hospital Zurich, Institute of Diagnostic Radiology, Zurich (Switzerland); Wildi, Stefan [University Hospital Zurich, Department of Visceral and Transplant Surgery, Zurich (Switzerland); Bauerfeind, Peter [University Hospital Zurich, Division of Gastroenterology, Zurich (Switzerland)

    2007-06-15

    This study was conducted to determine the ability of multi-detector-row computed tomography (CT) to identify the source and etiology of acute gastrointestinal bleeding. Eighteen patients with acute upper (n = 10) and lower (n = 8) gastrointestinal bleeding underwent 4-detector-row CT (n = 6), 16-detector-row CT (n = 11), and 64-slice CT (n = 1) with an arterial and portal venous phase of contrast enhancement. Unenhanced scans were performed in nine patients. CT scans were reviewed to determine conspicuity of bleeding source, underlying etiology, and for potential causes of false-negative prospective interpretations. Bleeding sources were prospectively identified with CT in 15 (83%) patients, and three (17%) bleeding sources were visualized in retrospect, allowing the characterization of all sources of bleeding with CT. Contrast extravasation was demonstrated with CT in all 11 patients with severe bleeding, but only in 1 of 7 patients with mild bleeding. The etiology could not be identified on unenhanced CT scans in any patient, whereas arterial-phase and portal venous-phase CT depicted etiology in 15 (83%) patients. Underlying etiology was correctly identified in all eight patients with mild GI bleeding. Multi-detector-row CT enables the identification of bleeding source and precise etiology in patients with acute gastrointestinal bleeding. (orig.)

  8. Acute gastrointestinal bleeding: detection of source and etiology with multi-detector-row CT.

    Science.gov (United States)

    Scheffel, Hans; Pfammatter, Thomas; Wildi, Stefan; Bauerfeind, Peter; Marincek, Borut; Alkadhi, Hatem

    2007-06-01

    This study was conducted to determine the ability of multi-detector-row computed tomography (CT) to identify the source and etiology of acute gastrointestinal bleeding. Eighteen patients with acute upper (n = 10) and lower (n = 8) gastrointestinal bleeding underwent 4-detector-row CT (n = 6), 16-detector-row CT (n = 11), and 64-slice CT (n = 1) with an arterial and portal venous phase of contrast enhancement. Unenhanced scans were performed in nine patients. CT scans were reviewed to determine conspicuity of bleeding source, underlying etiology, and for potential causes of false-negative prospective interpretations. Bleeding sources were prospectively identified with CT in 15 (83%) patients, and three (17%) bleeding sources were visualized in retrospect, allowing the characterization of all sources of bleeding with CT. Contrast extravasation was demonstrated with CT in all 11 patients with severe bleeding, but only in 1 of 7 patients with mild bleeding. The etiology could not be identified on unenhanced CT scans in any patient, whereas arterial-phase and portal venous-phase CT depicted etiology in 15 (83%) patients. Underlying etiology was correctly identified in all eight patients with mild GI bleeding. Multi-detector-row CT enables the identification of bleeding source and precise etiology in patients with acute gastrointestinal bleeding.

  9. Acute aortic syndromes: Role of multi-detector row CT

    Energy Technology Data Exchange (ETDEWEB)

    Salvolini, Luca; Renda, Pietro [Department of Radiology, University ' Politecnica delle Marche' , Ancona (Italy); Fiore, Davide [Department of Radiology, University of Padova, Padova (Italy); Scaglione, Mariano [Emergency and Trauma CT Section, Department of Radiology, Cardarelli Hospital, Naples (Italy); Piccoli, GianPiero [Cardiosurgery Division, Ospedali Riuniti ' Torrette-Lancisi-Salesi' , Ancona (Italy); Giovagnoni, Andrea [Department of Radiology, University ' Politecnica delle Marche' , Ancona (Italy)], E-mail: a.giovagnoni@univpm.it

    2008-03-15

    Acute thoracic aortic syndromes encompass a spectrum of emergencies including aortic dissection, intramural haematoma, penetrating atherosclerotic ulcer and aneurysm rupture. All these life-threatening conditions require prompt diagnosis and appropriate management. To date multi-detector row Computed Tomography represents a valuable diagnostic tool especially in the emergency setting. This paper focus on the use of multi-detector row Computed Tomography in the evaluation of acute thoracic aortic syndromes and illustrates the key imaging findings related to each disease.

  10. Use of multidetector row CT with volume renderings in right lobe living liver transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Ishifuro, Minoru; Akiyama, Yuji; Kushima, Toshio [Department of Radiology, Hiroshima University Medical Hospital, 1-2-3, Kasumi-cho, Minami-ku, Hiroshima 734-8551 (Japan); Horiguchi, Jun; Nakashige, Aya; Tamura, Akihisa; Marukawa, Kazushi; Fukuda, Hiroshi; Ono, Chiaki; Ito, Katsuhide [Department of Radiology, Division of Medical Intelligence and Informatics, Programs for Applied Biomedicine, Graduate School of Biomedical Science, Hiroshima University, 1-2-3, Kasumi-cho, Minami-ku, Hiroshima 734-8551 (Japan)

    2002-10-01

    Multidetector row CT is a feasible diagnostic tool in pre- and postoperative liver partial transplantation. We can assess vascular anatomy and liver parenchyma as well as volumetry, which provide useful information for both donor selection and surgical planning. Disorders of the vascular and biliary systems are carefully observed in recipients. In addition, we evaluate liver regeneration of both the donor and the recipient by serial volumetry. We present how multidetector row CT with state-of-the-art three-dimensional volume renderings may be used in right lobe liver transplantation. (orig.)

  11. Multislice CT of the pelvis: dose reduction with regard to image quality using 16-row CT

    Energy Technology Data Exchange (ETDEWEB)

    Gurung, Jessen; Khan, M. Fawad; Maataoui, Adel; Herzog, C.; Vogl, Thomas J. [Johann Wolfgang Goethe University, Institute for Diagnostic and Interventional Radiology, Frankfurt am Main (Germany); Bux, R.; Bratzke, H. [Johann Wolfgang Goethe University, Institute for Forensic Medicine, Frankfurt am Main (Germany); Ackermann, Hanns [Johann Wolfgang Goethe University, Institute for Epidemiology and Medical Statistics, Frankfurt am Main (Germany)

    2005-09-01

    To optimize examination protocols of 16-row multi-detector CT (MDCT) of pelvis for dose reduction with regard to image quality. MDCT of pelvis was performed on 12 cadaver specimens with stepwise reduction of tube current from 160 mA (113, 80, 56, 40, 28) to 20 mA at 120 kV. Scan parameters were 16 x 1.5 mm collimation. Reconstructions of axial and coronal images were used for evaluation of cortex, trabeculum, image quality, image noise, acetabulum and iliosacral (ISJ) joints. After data were blinded, evaluation of images was done by three radiologists according to 5-point Likert scale. Accuracy of the observers in sorting films according to dose reduction was determined with kappa coefficient. Mean values of image evaluation were determined. Pronounced deterioration of image quality for all criteria was observed between 80 and 28 mA. Adequate image quality was obtained at 40 mA [effective dose (E): 2.2 mSv, CTDI{sub w}: 2.8 mGy] for criterion detailed definition of acetabulum and ISJ and at 80 mA (E: 4.4 mSv, CTDI{sub w}: 5.6 mGy) for remaining criteria. Moderate agreement was observed between the three observers (kappa coefficient: 0.31). All observers were excellent in arranging images according to decreasing dose. Using 16-row MDCT image quality of pelvis is acceptable at 80 mA and 120 kV. This translates into a dose reduction of 33% of average value of the nationwide survey of the German Roentgen Society (1999) for this type of examination. (orig.)

  12. Multidetector-row CT duodenography in familial adenomatous polyposis: a pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, S.A.; Halligan, S. E-mail: s.halligan@imperial.ac.uk; Moore, L.; Saunders, B.P.; Gallagher, M.; Phillips, R.K.S.; Bartram, C.I

    2004-10-01

    AIM: To investigate the feasibility of using multidetector-row computed tomography (CT) duodenography to stage duodenal polyposis in patients with familial adenomatous polyposis. MATERIALS AND METHODS: Six patients underwent multidetector-row CT duodenography before upper gastrointestinal endoscopy. A single-blinded radiologist used a surface shaded three-dimensional endoluminal fly though and two-dimensional axial and multiplanar reformats to assign a score for maximum polyp size and number based on the Spigelman classification. Comparison was made with the corresponding Spigelman scores obtained from subsequent endoscopy. RESULTS: CT duodenography was technically successful in five of six patients. The CT derived Spigelman score based on maximum polyp size was accurate in all five patients. The CT derived Spigelman score based on polyp number was accurate in only two cases: Polyp number was overestimated in one patient and underestimated in a further two. In retrospect, fine carpeting of tiny duodenal polyps was poorly visualized with CT. CONCLUSIONS: CT duodenography is technically feasible and accurately predicts maximum polyp size but CT estimates of polyp number are relatively inaccurate. CT duodenography potentially has a useful role for duodenal surveillance in those patients intolerant of conventional endoscopy.

  13. Pancreatico-colonicfistula-demonstrated by multidtector-row CT

    Energy Technology Data Exchange (ETDEWEB)

    Srinivasan, Sivasubramanian; Subramanian, Manickam; Lim, Tze Chwan; Shenoy, Jagadish; Majumder, Arunesh [Khoo Teck Puat Hospital, Singapore (Singapore)

    2015-04-15

    A 25-year-old man presented to the emergency department with a history of corrosive (turpentine) ingestion. Clinically, the patient had metabolic acidosis and his total white cell count was 28600/mm{sup 3}. Computed tomography (CT) scan of the thorax and abdomen revealed diffuse thickening of the esophagus, stomach and duodenum. Minimal free fluid was present in the abdomen. The patient was first stabilised and step wise reconstruction of the gastro-intestinal tract was performed after esophagectomy, gastrectomy, pancreatic oduodenectomy, cholecystectomy, choledocho-jejenostomy and creation of a feeding jejenostomy.

  14. [Multidetector row CT in assessment of coronary artery calcification on hemodialisis].

    Science.gov (United States)

    Caro, P; Delgado, R; Dapena, F; Núñez, A

    2007-01-01

    Vascular calcification is a strong predictor of cardiovascular and all-cause mortality. Coronary artery calcification is more frequent, more extensive and progresses more rapidly in CKD than in general population. They are also considered a marker of coronary heart disease, with high prevalence and functional significance. It suggests that detection and surveillance may be worthwhile in general clinical practice. New non-invasive image techniques, like Multi-detector row CT, a type of spiral scanner, assess density and volume of calcification at multiple sites and allow quantitative scoring of vascular calcification using calcium scores analogous to those from electron-beam CT. We have assessed and quantified coronary artery calcification with 16 multidetector row CT in 44 patients on hemodialysis and their relationship with several cardiovascular risk factors. Coronary artery calcification prevalence was of 84 % with mean calcium score of 1580 +/- 2010 ( r 0-9844) with calcium score > 400 in 66% of patients. It was usually multiple, affecting more than two vessels in more than 50%. In all but one patient, left anterior descending artery was involved with higher calcium score level at right coronary artery. Advanced age, male, diabetes, smoking, more morbidity, cerebrovascular disease previous, and calcium-binders phosphate and analogous vitamin D treatment would seem to be associated with coronary artery calcification. Coronary artery calcification is very frequent and extensive, usually multiple and associated to modifiable risk factors in hemodialysis patients. Multi-detector-row CT seems an effective, suitable, readily applicable method to assess and quantify coronary artery calcification.

  15. T-staging of gastric cancer of air-filling multidetector-row CT: Comparison with hydro-multidetector-row CT

    Energy Technology Data Exchange (ETDEWEB)

    Kumano, Seishi, E-mail: kumano@radiol.med.kindai.ac.jp [Department of Radiology, Kinki University School of Medicine, Osakasayama, Osaka 589-8511 (Japan); Okada, Masahiro; Shimono, Taro; Kuwabara, Masatomo; Yagyu, Yukinobu; Imaoka, Izumi; Ashikaga, Ryuichiro; Ishii, Kazunari; Murakami, Takamichi [Department of Radiology, Kinki University School of Medicine, Osakasayama, Osaka 589-8511 (Japan)

    2012-11-15

    Purpose: The purpose of this study was to evaluate the accuracy of T-staging of gastric cancer by air-filling multidetector-row CT (air-MDCT) compared with water-filling MDCT (hydro-MDCT). Materials and methods: One hundred fifteen patients with histologically diagnosed gastric cancer were included in this study. Fifty-eight patients underwent air-MDCT, and the remaining 57 had hydro-MDCT using a 64-channel scanner. Based on the volumetric data of contrast-enhanced MDCT obtained about 75 s after intravenously injecting 525 mg iodine per kilogram patients weight (525 mgI/kg) nonionic contrast material at the rate of 2 ml/s, oblique coronal and oblique sagittal multi-planar reformatted images perpendicular to the stomach wall, including the tumor, were reconstructed on a workstation. Mural invasion of gastric cancer into the gastric wall, as visualized by CT, was classified according to the TNM classification, and the results of T-staging by MDCT were compared with those by pathologic analysis after surgery. Results: Correct assessment of T-staging by air-CT was achieved in 48 of 58 patients (83%), and that by hydro-MDCT was 49 of 57 patients (86%). The sensitivity, specificity, and accuracy of the technique in determining the invasion of serosa were 88%, 93%, and 91% for air-CT and 83%, 95%, and 91% for hydro-CT. There were no significant differences between hydro-MDCT and air-MDCT in sensitivity (P = 0.73), specificity (P = 0.71) and accuracy (P = 0.98). Conclusion: Air-MDCT is a very valuable tool in T-staging of gastric cancer as well as hydro-MDCT.

  16. Comparison of cerebral blood flow data obtained by computed tomography (CT) perfusion with that obtained by xenon CT using 320-row CT.

    Science.gov (United States)

    Takahashi, Satoshi; Tanizaki, Yoshio; Kimura, Hiroaki; Akaji, Kazunori; Kano, Tadashige; Suzuki, Kentaro; Takayama, Youhei; Kanzawa, Takao; Shidoh, Satoka; Nakazawa, Masaki; Yoshida, Kazunari; Mihara, Ban

    2015-03-01

    Cerebral blood flow (CBF) data obtained by computed tomography perfusion (CTP) imaging have been shown to be qualitative data rather than quantitative, in contrast with data obtained by other imaging methods, such as xenon CT (XeCT) imaging. Thus, interpatient comparisons of CBF values themselves obtained by CTP may be inaccurate. In this study, we have compared CBF ratios as well as CBF values obtained from CTP-CBF data to those obtained from XeCT-CBF data for the same patients to determine CTP-CBF parameters that can be used for interpatient comparisons. The data used in the present study were obtained as volume data using 320-row CT. The volume data were applied to an automated region of interest-determining software (3DSRT, version 3.5.2 ) and converted to 59 slices of 2 mm interval standardized images. In the present study, we reviewed 10 patients with occlusive cerebrovascular diseases (CVDs) undergoing both CTP and XeCT in the same period. Our study shows that ratios of CBF measurements, such as hemodynamic stress distribution (perforator-to-cortical flow ratio of middle cerebral artery [MCA] region) or the left/right ratio for the region of the MCA, calculated using CTP data have been shown to correlate well with the same ratios calculated using XeCT data. These results suggest that such CBF ratios could be useful for generating interpatient comparisons of CTP-CBF data obtained by 320-row CT among patients with occlusive CVD.

  17. Multidetector-Row CT Findings of an Internal Supravesical Hernia: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sang Won; Shin, Hyeong Cheol; Kim, Hyung Hwan; Kim, Young Tong; Kim, Il Young; Kang, Kil Ho [Soonchunhyang University Cheonan Hospital, Cheonan (Korea, Republic of)

    2010-02-15

    A supravesical hernia occurs in the supravesical fossa and is either classified as an external or internal supravesical hernia. Most patients with internal supravesical hernias present with small bowel obstruction. Internal supravesical hernias are less common than external supravesical hernia. To date, there are few reports describing the radiological findings of supravesical hernias. To our knowledge, this is the first reported multidetector row CT (MDCT) depiction of this type of hernia. We report here on the MDCT findings of a patient with an internal supravesical hernia presenting with small bowel obstruction

  18. Pitfalls in detection of acute gastrointestinal bleeding with multi-detector row helical CT.

    Science.gov (United States)

    Stuber, T; Hoffmann, M H K; Stuber, G; Klass, O; Feuerlein, S; Aschoff, A J

    2009-07-01

    Contrast-enhanced multi-detector row helical CT angiography is establishing itself as an accurate, rapid, and non-invasive diagnostic modality in patients with acute gastrointestinal bleeding. On arterial phase MDCT images ongoing hemorrhage can be revealed as an area of active extravasation of contrast material within the bowel lumen. This pictorial essay gives a short overview of current diagnostic modalities in assessing acute GI tract bleeding, typical MDCT findings, and depicts potential pitfalls in the detection of acute GI bleeding with MDCT.

  19. Bronchial anatomy of left lung: a study of multi-detector row CT.

    Science.gov (United States)

    Zhao, Xinya; Ju, Yuanrong; Liu, Cheng; Li, Jianfeng; Huang, Min; Sun, Jian; Wang, Tao

    2009-02-01

    Familiarity with prevailing pattern and variations in the bronchial tree is not only essential for the anatomist to explain bronchial variation in bronchial specimens, but also useful for guiding bronchoscopy and instructing pulmonary segmental resection. The purpose of this study was designed to demonstrate various branching patterns of left lung with 3D images, with special attention given to identify the major types at transverse thin-section CT. Two hundred and sixteen patients with routine thorax scans were enrolled. The images of bronchial tree, virtual bronchoscopy were reconstructed using post-processing technique of multi-detector row CT. We attempted to classify the segmental bronchi by interpreting the post-processing images, and identified them in transverse thin-section CT. Our results showed that the segmental bronchial ramifications of the left superior lobe were classified into three types mainly, i.e., common stem of apical and posterior segmental bronchi (64%, 138/216); trifurcation (23%, 50/216); common stem of apical and anterior segmental bronchi (10%, 22/216), and they could be identified at two typical sections of transverse thin-section CT. There were two major types in left basal segmental bronchi, i.e., bifurcation (75%, 163/216), trifurcation (18%, 39/216), and they could also be identified at two typical sections of transverse thin-section CT. In conclusion, our study have offered simplified branching patterns of bronchi and demonstrated various unusual bronchial branching patterns perfectly with 3D images, and have also revealed how to identify the main branching patterns in transverse thin-section CT.

  20. Optimizing bowel preparation for multidetector row CT colonography: Effect of Citramag and Picolax

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, S.A.; Halligan, S. E-mail: s.halligan@ic.ac.uk; Goh, V.; Morley, S.; Atkin, W.; Bartram, C.I

    2003-09-01

    AIM: To compare the adequacy and acceptability of Picolax and Citramag bowel cleansing agents for CT colonography. MATERIALS AND METHODS: Multidetector row CT colonography was performed in 124 subjects; 43 had been prepared with Picolax and 81 with Citramag. Datasets were assessed for retained fluid and solid residue, and overall adequacy of segmental visualization. Preparation acceptability was also assessed. RESULTS: There was significantly less retained fluid with Picolax. The odds of being in the next higher category for retained fluid when using Picolax were 0.33 (CI: 0.22-0.50, p<0.0001) when compared with Citramag, for all segments combined. However there was significantly more retained solid residue with Picolax. The odds of being in the next higher category for retained residue when using Picolax were 2.44 (CI: 1.41-4.24, p=0.002) when compared with Citramag, for all segments combined. There was no significant difference with respect to overall segmental visualization: the odds of a segment being adequately visualized when using Picolax were 1.52 (CI: 0.88-2.65, p=0.14) when compared with Citramag. There was no significant difference with respect to acceptability. CONCLUSION: Picolax results in a significantly drier colon than Citramag and associated with more retained residue. We found Picolax the more suitable preparation for CT colonography.

  1. Multidetector Row CT Detection of a Patent Foramen Ovale Causing Neurologic Deficits in an Adolescent: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jung Bin [Dept. of Radiology, Soonchunhyang University College of Medicine, Bucheon (Korea, Republic of); Kim, Dong Hun; Oh, Jae Hee [Dept. of Radiology, Chosun University College of Medicine, Gwangju (Korea, Republic of); Seo, Hye Sun [Dept. of Internal Medicine, Soonchunhyang University College of Medicine, Bucheon (Korea, Republic of); Suk, Eun Ha [Dept. of Anesthesiology and Pain Medicine, Asan Medical Center, Seoul (Korea, Republic of)

    2012-02-15

    A patent foramen ovale (PFO) is a persisting fetal circulation structural abnormality that can cause neurologic deficits such as migraine and cryptogenic stroke. Here we report a case of PFO diagnosed by cardiac multidetector row CT in an adolescent male with chronic migraine and stroke.

  2. Whole-brain CT digital subtraction angiography of cerebral dural arteriovenous fistula using 320-detector row CT

    Energy Technology Data Exchange (ETDEWEB)

    Fujiwara, Hirokazu; Momoshima, Suketaka; Kuribayashi, Sachio [Keio University, Department of Diagnostic Radiology, School of Medicine, Tokyo (Japan); Akiyama, Takenori [Keio University, Department of Neurosurgery, School of Medicine, Tokyo (Japan)

    2013-07-15

    The purpose of this study was to evaluate the usefulness of CT digital subtraction angiography (CTDSA) by using 320-detector row CT in the diagnosis and classification of cerebral dural arteriovenous fistula (dAVF) and comparing it with DSA as the standard reference. A total of 29 CTDSA/DSA from 25 patients with dAVF were retrospectively evaluated by two neuroradiologists. The presence, Cognard classification, and feeding arteries of dAVFs on CTDSA were assessed according to DSA. DSA depicted 33 dAVFs in 28 cases. By consensus reading, CTDSA correctly detected 32 dAVFs in 27 cases and properly graded 31 lesions. The intermodality agreement for the presence and classification of dAVFs was excellent (kappa = 0.955 and 0.921, respectively). CTDSA detected 77 of 109 feeding arteries (70.6 %) in 25 cases. The intermodality agreement for the feeding arteries was good (kappa = 0.713). Although CTDSA is limited in temporal and spatial resolution in comparison with DSA, it is an effective non-invasive tool for the detection and classification of dAVF. (orig.)

  3. Multidetector-row CT angiography of upper- and lower-extremity peripheral arteries

    Energy Technology Data Exchange (ETDEWEB)

    Willmann, J.K.; Wildermuth, S. [Inst. of Diagnostic Radiology, Univ. Hospital Zurich, Zurich (Switzerland)

    2005-11-15

    With the introduction of multidetector-row CT (MDCT) technology indications for MDCT angiography have expanded to include assessment of the peripheral arteries of the upper and lower extremities. Combined with patient- and scanner-adjusted CT data acquisition and contrast medium application strategies, an accurate and reliable evaluation of the peripheral arteries of the upper and lower extremities is possible. MDCT angiography is cost-effective and accurate for detection of arterial stenosis and occlusion in patients with peripheral arterial disease (PAD). MDCT angiography allows postoperative assessment of peripheral arterial bypass grafts, including bypass graft stenosis and occlusion, as well as presence of aneurysms or arteriovenous fistulas. In addition, MDCT angiography is helpful in particular for visualization of arterial bypass grafts with a complicated extra-anatomical course. Furthermore, pre-operative peripheral vascular mapping can be performed by using MDCT angiography. Finally, due to the integration of MDCT scanners in many trauma centres, MDCT angiography is increasingly being used for assessment of traumatic arterial injuries. This article gives an overview of technical aspects of peripheral MDCT angiography, including scanning parameters, contrast medium application, image postprocessing and radiation exposure, and summarizes the most frequent acute and non-acute indications of MDCT angiography for assessment of the upper- and lower-extremity peripheral arteries. (orig.)

  4. Prevalence and configuration of pulmonary nodules on multi-row CT in children without malignant diseases

    Energy Technology Data Exchange (ETDEWEB)

    Renne, Julius; Wacker, Frank; Berthold, Lars-Daniel; Weidemann, Juergen [Hannover Medical School, Institute for Diagnostic and Interventional Radiology, Hannover (Germany); Linderkamp, Christin [Hannover Medical School, Pediatric Oncology, Hannover (Germany)

    2015-09-15

    To assess the prevalence and morphologic characterization of pulmonary nodules in children on a chest computed tomography (CT). Two hundred and fifty-nine trauma chest CTs in children aged 0-18 years were retrospectively reviewed by two radiologists, each with more than 10 years of experience. Images were acquired on a 64-row CT. Pulmonary lobes with trauma affections such as contusion or haemorrhage were excluded. All pulmonary nodules were evaluated for distance from the pleural surface, location, calcification and size on axial slices. A total of 1,190/1,295 (92 %) pulmonary lobes without traumatic injury were included in this study. In 86 of 259 (33 %) patients, 131 pulmonary nodules were detected. Number of nodules per patient ranged from 1 to 4. Calcifications were seen in 19 % (25) of all nodules. Diameters ranged from 1 to 5 mm. 59 % (77) were located in the lower lobes, 9 % (12) in the middle lobe and 32 % (42) in the upper lobes. 84 % of the non-calcified nodules >2 mm showed a slightly angular or triangular (mostly pleural nodes) shape. Pulmonary nodules smaller than 5 mm can be detected frequently in children without malignant disease and are predominantly located in the lower lobes. (orig.)

  5. Effect of saline flush on enhancement of proximal and distal segments using 320-row coronary CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Tomizawa, Nobuo, E-mail: tomizawa-tky@umin.ac.jp [Department of Radiology, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Suzuki, Fumio; Akahane, Masaaki [Department of Radiology, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Torigoe, Rumiko [Toshiba Medical Systems Corporation, Tokyo Metropolitan Regional Office, 1-6, Tsukuda 2-Chome, Chuo-ku, Tokyo 104-0051 (Japan); Kiryu, Shigeru [Department of Radiology, Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639 (Japan); Ohtomo, Kuni [Department of Radiology, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2013-08-15

    Objective: To investigate the effect of saline flush on coronary CT angiography of proximal, middle, and distal coronary artery segments, using 320-row CT, and to compare two injection duration protocols as to amount of contrast in the right heart chambers. Methods: This retrospective study was approved by the local ethics committee, and the requirement for informed consent to participate in this study was waived. The final study group included 108 patients who underwent coronary CT angiography. The first 36 patients received contrast medium without saline flush (group 1); the next 36 patients received contrast medium for 14 s and saline flush (group 2); the last 36 patients received contrast medium for 12 s and saline flush (group 3). The CT number, noise, contrast-to-noise ratio (CNR), and number of segments with a CT number greater than 325 Hounsfield units (HU) were recorded for proximal, middle, and distal segments. Results: The CT numbers and the CNR in groups 2 and 3 were significantly higher than that in group 1 (p < 0.005); the difference between groups 2 and 3 was not significant. The proportion of segments greater than 325 HU improved with saline flush (p < 0.05), with a larger improvement in the distal segments. Conclusions: Saline flush improves enhancement and CNR of coronary arteries, particularly of distal segments, in coronary CT angiography using 320-row CT. An average contrast medium injection of 44 mL was feasible using a saline flush.

  6. Evaluation of angiogenesis in colorectal carcinoma with multidetector-row CT multislice perfusion imaging

    Energy Technology Data Exchange (ETDEWEB)

    Feng Shiting, E-mail: fst1977@163.co [Department of Radiology, First Affiliated Hospital of SunYat-sen University, Guangzhou 510080 (China); Sun Canhui, E-mail: canhuisun@sina.co [Department of Radiology, First Affiliated Hospital of SunYat-sen University, Guangzhou 510080 (China); Li Ziping, E-mail: liziping163@tom.co [Department of Radiology, First Affiliated Hospital of SunYat-sen University, Guangzhou 510080 (China); Mak, Henry Ka-Fung, E-mail: makkf@hkucc.hku.h [Department of Diagnostic Radiology, University of Hong Kong, Hong Kong (China); Peng Zhenpeng, E-mail: ppzhen@21cn.co [Department of Radiology, First Affiliated Hospital of SunYat-sen University, Guangzhou 510080 (China); Guo Huanyi, E-mail: guohuanyi@163.co [Department of Radiology, First Affiliated Hospital of SunYat-sen University, Guangzhou 510080 (China); Meng Quanfei, E-mail: mzycoco@gmail.co [Department of Radiology, First Affiliated Hospital of SunYat-sen University, Guangzhou 510080 (China)

    2010-08-15

    To evaluate the correlation between 64 multidetector-row CT (64MDCT) perfusion imaging in colorectal carcinoma and microvessel density (MVD) and vascular endothelial growth factor (VEGF), 64MDCT perfusion imaging was performed in 33 patients with pathologically verified colorectal carcinoma. These images were analyzed with perfusion functional software, and time-density curves (TDC) were created for the region of interest (ROI) encompassing the tumor, the target artery and vein. The individual perfusion maps generated indicated blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability-surface area product (PS). MVD and VEGF were evaluated by immunohistochemical staining with anti-CD34 and anti-VEGF, respectively. Correlations between MVD or VEGF with CT perfusion parameters and clinicopathological factors (Dukes' stages, invasion depth, and lymph node and liver metastasis) were also investigated. MVD in the colorectal carcinoma was 22.61 {+-} 9.01 per x200 field. The scores obtained for VEGF expression were 4.15 {+-} 1.09. VEGF staining was positive in 25 of 29 tumors (86.2%). There was no significant correlation between the presence of MVD, VEGF expression and clinicopathological factors (P > 0.05). There was also no correlation between MVD, VEGF expression, and any dynamic CT parameters (P > 0.05). The BV and MTT were significantly higher in tumors demonstrating serous coat invasion than in those without it (t = -2.63, -2.24, P = 0.0137, 0.0331, respectively). BV was also significantly correlated with tumor size (r = 0.41, P = 0.02). Neither BF nor PS was correlated with clinicopathological factors. In conclusion, 64MDCT perfusion imaging, MVD, and VEGF may reflect angiogenic activity, but no significant correlation among these factors.

  7. Optimal iodine dose for 3-dimensional multidetector-row CT angiography of the liver

    Energy Technology Data Exchange (ETDEWEB)

    Ichikawa, Tomoaki, E-mail: ichikawa@yamanashi.ac.jp [Department of Radiology, University of Yamanashi, Yamanashi (Japan); Motosugi, Utaroh; Morisaka, Hiroyuki; Sou, Hironobu; Onohara, Kojiro; Sano, Katsuhiro; Araki, Tsutomu [Department of Radiology, University of Yamanashi, Yamanashi (Japan)

    2012-09-15

    Purpose: To clarify the optimal iodine dose of contrast material for 3-dimensional multidetector-row CT angiography (3D-MDCTA) of the venous vasculature of the liver using volume rendering technique. Materials and methods: This study included 103 patients who were randomly assigned to 5 contrast-enhanced MDCT protocol groups with different body-weight-tailored doses of contrast material: 500, 600, 630, 650, and 700 mgI/kg body weight. The arterial, portal, and hepatic parenchymal phases were obtained to evaluate enhancement values of the aorta, portal vein, and hepatic vein. Visualization of the portal and hepatic veins on the volume-rendering images of 3D-MDCTA was evaluated using a 5-point grade. Dunnett's test was used to compare the mean enhancement value and mean grades of image quality (700 mgI/kg dose group was control). Results: The mean enhancement values of portal and hepatic vein in the group with 500 and 600 mgI/kg were significantly lower than those of the control group. During visual assessment, a significantly lower mean grades were observed in 500 mgI/kg groups for the portal vein, and 500 and 600 mgI/kg groups for hepatic vein. There were no significant intergroup differences in mean enhancement values and visual assessment among the groups using 630 mgI/kg or more. Conclusion: Iodine doses of 630 mgI/kg was recommended for 3D-MDCTA.

  8. Bilateral asymmetrical duplicated origin of vertebral arteries: Multidetector row CT angiographic study

    Directory of Open Access Journals (Sweden)

    C S Rameshbabu

    2014-01-01

    Full Text Available Bilateral duplicated origin of V-1 segment of vertebral arteries is an extremely rare vascular variant and only two such cases have been reported so far. Presence of this vascular abnormality was observed incidentally in a 36-year-old male patient, with a complaint of dizziness, evaluated by multidetector row computed tomography (CT angiography. Two limbs of the right vertebral artery arose from the right subclavian artery and fused to form a single vessel at the interval between fourth and fifth cervical vertebrae, which entered the foramen transversarium of fourth cervical vertebra. On the left side, the medial limb originated directly from the arch of aorta and the lateral limb from the left subclavian artery, and both united at the interval between fifth and sixth cervical vertebrae to form a single vessel which entered the foramen transversarium of fifth cervical vertebra. No other cerebrovascular pathology like aneurysm, fenestration, dissection, and stenosis was detected, which could be correlated with the symptoms of the patient. This rare congenital vascular anomaly has diagnostic and therapeutic implications in any intervention involving the vertebral artery.

  9. Optimized image reconstruction for detection of deep venous thrombosis at multidetector-row CT venography

    Energy Technology Data Exchange (ETDEWEB)

    Das, Marco; Muehlenbruch, Georg; Mahnken, Andreas Horst; Guenther, Rolf W.; Wildberger, Joachim Ernst [University Hospital, University of Technology (RWTH), Department of Diagnostic Radiology, Aachen (Germany); Weiss, Claudia [RWTH Aachen, Institute of Medical Statistics, Aachen (Germany); Schoepf, U. Joseph [Medical University of South Carolina, Department of Radiology, Charleston, SC (United States); Leidecker, Christianne [Institute of Medical Physics, University of Erlangen, Erlangen (Germany)

    2006-02-01

    The aims of this study were to optimize image quality for indirect CT venography (sequential versus spiral), and to evaluate different image reconstruction parameters for patients with suspected deep venous thrombosis (DVT). Fifty-one patients (26/25 with/without DVT) were prospectively evaluated for pulmonary embolism (PE) with standard multidetector-row computed tomography (MDCT) protocols. Retrospective image reconstruction was done with different slice thicknesses and reconstruction increments in sequential and spiral modes. All reconstructions were read for depiction of DVT and to evaluate best reconstruction parameters in comparison with the thinnest reconstruction (''gold standard''). Image noise and venous enhancement were measured as objective criteria for image quality. Subjective image quality was rated on a four-point scale. Effective dose was estimated for all reconstructions. In sequential 10/50 reconstruction DVT was completely detected in 13/26 cases, partially in 10/26 cases and was not detected at all in 3/26 cases, and 15/26, 9/26 and 2/26 cases for the 10/20 reconstruction, respectively. DVT was completely detected in all spiral reconstructions. Image noise ranged between 14.8-29.1 HU. Median image quality was 2. Estimated effective dose ranged between 2.3 mSv and 11.8 mSv. Gaps in sequential protocols may lead to false negative results. Therefore, spiral scanning protocols for complete depiction of DVT are mandatory. (orig.)

  10. Image analysis of intracranial high perfusion lesion by whole brain one-stop imaging technique with 320 detector rows CT

    Directory of Open Access Journals (Sweden)

    Fei-zhou DU

    2014-03-01

    Full Text Available Objective  The perfusion and vascular architecture features were investigated and evaluated by use of one-stop imaging technique with 320 rows CT for exploring the clinical value of one-stop imaging technique in the diagnosis of intracranial lesions. Methods  The perfusion parameters and vascular architecture of intracranial high perfusion lesions of 52 patients were collected in General Hospital of Chengdu Command from Oct. 2010 to Apr. 2013, who were examined by one-stop imaging technique with 320 rows CT, were retrospectively analyzed. The perfusion values of normal contralateral cerebral tissue were used as control to analyze the perfusion and vascular architecture features of injured parts. Results  Of the 52 patients, there were 16 cases of subacute cerebral infarction, 9 cases of arteriovenous malformation, 7 cases of hemangioma, 12 cases of meningioma, and 8 cases of glioma. All the patients showed elevated CBV and/or CBF and different changes in mean transit time (MTT, time to peak (TTP and delay time (Delay. In the cases of subacute cerebral infarction, the parameters of MTT, TTP and Delay increased. In the cases of arteriovenous malformation, all the parameters decreased. In the cases of hemangioma, the MTT decreased, while TTP and Delay increased. In the cases of glioma, the TTP and Delay increased, while the change of MTT varied. Meanwhile, abnormality of vascular structures was found in all the cases by CT angiography. Conclusion  With whole brain perfusion and one-stop vascular imaging with 320 rows CT, the perfusion characteristics of intracranial lesions can be revealed completely, including blood supply and microcirculation changes in the lesions, and it may be of benefit in guiding the clinical diagnosis and treatment. DOI: 10.11855/j.issn.0577-7402.2014.03.10

  11. SimDoseCT: dose reporting software based on Monte Carlo simulation for a 320 detector-row cone-beam CT scanner and ICRP computational adult phantoms

    Science.gov (United States)

    Cros, Maria; Joemai, Raoul M. S.; Geleijns, Jacob; Molina, Diego; Salvadó, Marçal

    2017-08-01

    This study aims to develop and test software for assessing and reporting doses for standard patients undergoing computed tomography (CT) examinations in a 320 detector-row cone-beam scanner. The software, called SimDoseCT, is based on the Monte Carlo (MC) simulation code, which was developed to calculate organ doses and effective doses in ICRP anthropomorphic adult reference computational phantoms for acquisitions with the Aquilion ONE CT scanner (Toshiba). MC simulation was validated by comparing CTDI measurements within standard CT dose phantoms with results from simulation under the same conditions. SimDoseCT consists of a graphical user interface connected to a MySQL database, which contains the look-up-tables that were generated with MC simulations for volumetric acquisitions at different scan positions along the phantom using any tube voltage, bow tie filter, focal spot and nine different beam widths. Two different methods were developed to estimate organ doses and effective doses from acquisitions using other available beam widths in the scanner. A correction factor was used to estimate doses in helical acquisitions. Hence, the user can select any available protocol in the Aquilion ONE scanner for a standard adult male or female and obtain the dose results through the software interface. Agreement within 9% between CTDI measurements and simulations allowed the validation of the MC program. Additionally, the algorithm for dose reporting in SimDoseCT was validated by comparing dose results from this tool with those obtained from MC simulations for three volumetric acquisitions (head, thorax and abdomen). The comparison was repeated using eight different collimations and also for another collimation in a helical abdomen examination. The results showed differences of 0.1 mSv or less for absolute dose in most organs and also in the effective dose calculation. The software provides a suitable tool for dose assessment in standard adult patients undergoing CT

  12. Whole-brain 320-detector row dynamic volume CT perfusion detected crossed cerebellar diaschisis after spontaneous intracerebral hemorrhage

    Energy Technology Data Exchange (ETDEWEB)

    Fu, Jun; Chen, Wei-jian; Wang, Mei-hao; Li, Jian-ce; Zhang, Qian; Xia, Neng-zhi; Yang, Yun-jun [Wenzhou Medical University, Department of Radiology, First Affiliated Hospital, Wenzhou (China); Wu, Gui-yun [Cleveland Clinics Foundation, Department of Nuclear Medicine, Imaging Institute, Cleveland, OH (United States); Cheng, Jing-liang; Zhang, Yong [Zhengzhou University, Department of Radiology, First Affiliated Hospital, Zhengzhou (China); Zhuge, Qichuan [Wenzhou Medical University, Department of Neurosurgery, First Affiliated Hospital, Wenzhou (China)

    2014-11-09

    The purpose of this study was to evaluate the value of 320-detector row CT used to detect crossed cerebellar diaschisis (CCD) in patients with unilateral supratentorial spontaneous intracerebral hemorrhage (SICH). We investigated 62 of 156 patients with unilateral supratentorial SICH using 320-detector row CT scanning. Regional cerebral blood flow (rCBF), cerebral blood volume (rCBV), mean transit time (rMTT), and time to peak (rTTP) levels were measured in different regions of interest (ROIs) that were manually outlined on computed tomography perfusion (CTP) for the cerebrum, including normal-appearing brain tissue that surrounded the perilesional low-density area (NA) and the perihematomal low-density area (PA) in all patients and the cerebellum (ipsilateral and contralateral) in CCD-positive patients. Of 62 cases, a total of 14 met the criteria for CCD due to cerebellar perfusion asymmetry on CTP maps. In the quantitative analysis, significant differences were found in the perfusion parameters between the contralateral and ipsilateral cerebellum in CCD-positive cases. No significant differences were found between the CCD-positive group and the CCD-negative group according to the hematoma volume, NIHSS scores, and cerebral perfusion abnormality (each P > 0.05). The correlation analysis of the degree of NA, PA perfusion abnormality, and the degree of CCD severity showed negative and significant linear correlations (R, -0.66∝-0.56; P < 0.05). 320-detector row CT is a robust and practicable method for the comprehensive primary imaging work-up of CCD in unilateral supratentorial SICH patients. (orig.)

  13. Multidetector-Row CT Findings of a Preduodenal Portal Vein Associated with Polysplenic Syndrome in an Adult: A Case Report

    Energy Technology Data Exchange (ETDEWEB)

    Song, Hyun; Lee, Su Lim; Ku, Young Mi; Chun, Chang Woo [Dept. of Radiology, Uijeongbu St. Mary' s Hospital, The Catholic University of Korea College of Medicine, Uijeongbu (Korea, Republic of)

    2012-03-15

    Preduodenal portal vein (PDPV) is a rare developmental anomaly in which the portal vein runs at the ventral side of the duodenum instead of at an intrapancreatic location. Understanding of this anomaly is of considerable surgical importance, because it may cause unintended portal vein injury during operations involving the gall bladder or duodenum. We recently experienced PDPV associated with polysplenia syndrome in a 49-year-old male patient who complained of persistent epigastric pain. CT portal venography with thin slab maximal intensity projection and volume rendering demonstrated the unique feature of convex anastomosis between the L-shaped mesenterico-portal vein and mesenterico-splenic vein in the mid abdomen. We report here the Multidetector-row CT findings of a rare case of PDPV.

  14. Multiplanar reformations and minimum intensity projections using multi-detector row CT for assessing anomalies and disorders of the pancreaticobiliary tree

    OpenAIRE

    Kim, Hyun Cheol; Yang, Dal Mo; Jin, Wook; Ryu, Chang Woo; Ryu, Jung Kyu; Park, Sung Il; Park, Seong Jin; Shin, Hyeong Cheol; Kim, Il Young

    2007-01-01

    CT scan is regarded as the imaging modality of choice in patients with pancreaticobiliary ductal abnormalities. However, the axial orientation of the CT images provides only limited anatomical view of pancreaticobiliary ductal abnormalities. The technological advances of multi-detector row CT and three-dimensional image processing in workstations allows rapid image acquisition and a short postprocessing time. In particular, multiplanar reformations (MPR) and minimum intensity projections (Min...

  15. Obscure gastrointestinal bleeding and small bowel pathology: comparison between wireless capsule endoscopy and multidetector-row CT enteroclysis.

    Science.gov (United States)

    Filippone, Antonella; Cianci, Roberta; Milano, Angelo; Valeriano, Sergio; Di Mizio, Veronica; Storto, Maria Luigia

    2008-01-01

    Obscure gastrointestinal bleeding is defined as bleeding of unknown origin, that persists or recurs after negative conventional barium contrast studies and upper and lower tract endoscopy. The causes of such a bleeding frequently arise in the small bowel, and they are represented by mucosal vascular abnormalities, neoplasms and other conditions such as Crohn's disease, Meckel's diverticulum, and vasculitis. Conventional barium contrast studies and push enteroscopy allow only a limited small bowel examination; moreover, intraoperative endoscopy may be inconclusive, since the small bowel is difficult to evaluate given its length and tortuous course. In the same way, angiographic diagnosis is stricktly related to the activity rate of hemorrhage. Wireless capsule endoscopy and multidetector-row CT enteroclysis are two recently developed minimally invasive techniques that may provide a complete small bowel examination, the first offering a direct visualization of the mucosal aspect, the second allowing evaluation of mural and extramural pathologies. This review is an update of the technique and clinical application of capsule endoscopy and multidetector-row CT enteroclysis in patients suffering from obscure small bowel bleeding.

  16. Evaluation of Deep Vein Thrombosis with Multidetector Row CT after Orthopedic Arthroplasty: a Prospective Study for Comparison with Doppler Sonography

    Energy Technology Data Exchange (ETDEWEB)

    Byun, Sung Su; Kim, Youn Jeong; Chun, Yong Sun; Kim, Won Hong [Inha University, College of Medicine, Incheon (Korea, Republic of); Kim, Jeong Ho; Park, Chul Hi [Gachon University, Gil Medical Center, Incheon (Korea, Republic of)

    2008-02-15

    This prospective study evaluated the ability of indirect 16-row multidetector CT venography, in comparison with Doppler sonography, to detect deep vein thrombosis after total hip or knee replacement. Sixty-two patients had undergone orthopedic replacement surgery on a total of 30 hip joints and 54 knee joints. The CT venography (scan delay time: 180 seconds; slice thickness/increment: 2/1.5 mm) and Doppler sonography were performed 8 to 40 days after surgery. We measured the z-axis length of the beam hardening artifact that degraded the image quality so that the presence of deep vein thrombosis couldn't be evaluated on the axial CT images. The incidence and location of deep vein thrombosis was analyzed. The diagnostic performance of the CT venograms was evaluated and compared with that of Doppler sonography as a standard of reference. The z-axis length (mean{+-}standard deviation) of the beam hardening artifact was 4.5{+-}0.8 cm in the arthroplastic knees and 3.9{+-}2.9 cm in the arthroplastic hips. Deep vein thrombosis (DVT) was found in the popliteal or calf veins on Doppler sonography in 30 (48%) of the 62 patients. The CT venography has a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 90%, 97%, 96%, 91% and 94%, respectively. The ability of CT venography to detect DVT was comparable to that of Doppler sonography despite of beam hardening artifact. Therefore, CT venography is feasible to use as an alternative modality for evaluating postarthroplasty patients.

  17. Suspected aortic dissection and other aortic disorders: multi-detector row CT in 373 cases in the emergency setting.

    Science.gov (United States)

    Hayter, Robert G; Rhea, James T; Small, Andrew; Tafazoli, Faranak S; Novelline, Robert A

    2006-03-01

    To retrospectively review the authors' experience with multi-detector row computed tomography (CT) for detection of aortic dissection in the emergency setting. The investigation was institutional review board approved, did not require informed patient consent, and was HIPAA compliant. In 373 clinical evaluations in the emergency setting, 365 patients suspected of having aortic dissection and/or other aortic disorders underwent multidetector CT. Criteria for acute aortic disorder were confirmed by using surgical and pathologic diagnoses or findings at clinical follow-up and any subsequent imaging as the reference standard. Positive cases were characterized according to type of disorder interpreted. Resulting sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated by using two-way contingency tables. All cases found to be negative for acute aortic disorders were grouped according to alternative CT findings. Sixty-seven (18.0%) of the 373 cases were interpreted as positive for acute aortic disorder. One hundred twelve acute aortic disorders were identified in these 67 cases: 23 acute aortic dissections, 14 acute aortic intramural hematomas, 20 acute penetrating aortic ulcers, 44 new or enlarging aortic aneurysms, and 11 acute aortic ruptures. Three hundred five (81.8%) cases were interpreted as negative for acute aortic disorder. In 48 negative cases, multidetector CT depicted alternative findings that accounted for the clinical presentation. Of these, three included both acute aortic disorders and alternative findings, and 45 included only alternative findings. One (0.3%) case was indeterminate for acute aortic disorder. Overall, 112 findings were interpreted as positive for acute aortic disorder, an alternative finding, or both at CT. No interpretations were false-positive, one was false-negative, 67 were true-positive, and 304 were true-negative. Sensitivity, specificity, PPV, NPV, and accuracy were

  18. Multidetector row computed tomography of acute pancreatitis: Utility of single portal phase CT scan in short-term follow up

    Energy Technology Data Exchange (ETDEWEB)

    Kwon, Yongwonn [Department of Radiology, Konkuk University Medical Center, 4-12, Hwayang-dong, Gwangjin-gu, Seoul 143-729 (Korea, Republic of); Park, Hee Sun, E-mail: heesun.park@gmail.com [Department of Radiology, Konkuk University Medical Center, 4-12, Hwayang-dong, Gwangjin-gu, Seoul 143-729 (Korea, Republic of); Kim, Young Jun; Jung, Sung Il; Jeon, Hae Jeong [Department of Radiology, Konkuk University Medical Center, 4-12, Hwayang-dong, Gwangjin-gu, Seoul 143-729 (Korea, Republic of)

    2012-08-15

    Objective: The purpose of this study is to evaluate the question of whether nonenhanced CT or contrast enhanced portal phase CT can replace multiphasic pancreas protocol CT in short term monitoring in patients with acute pancreatitis. Materials and methods: This retrospective study was approved by the Institutional Review Board. From April 2006 to May 2010, a total of 52 patients having acute pancreatitis who underwent initial dual phase multidetector row CT (unenhanced, arterial, and portal phase) at admission and a short term (within 30 days) follow up dual phase CT (mean interval 10.3 days, range 3-28 days) were included. Two abdominal radiologists performed an independent review of three sets of follow up CT images (nonenhanced scan, single portal phase scan, and dual phase scan). Interpretation of each image set was done with at least 2-week interval. Radiologists evaluated severity of acute pancreatitis with regard to pancreatic inflammation, pancreatic necrosis, and extrapancreatic complication, based on the modified CT severity index. Scores of each image set were compared using a paired t-test and interobserver agreement was evaluated using intraclass correlation coefficient statistics. Results: Mean scores of sum of CT severity index on nonenhanced scan, portal phase scan, and dual phase scan were 5.7, 6.6, and 6.5 for radiologist 1, and 5.0, 5.6, and 5.8 for radiologist 2, respectively. In both radiologists, contrast enhanced scan (portal phase scan and dual phase scan) showed significantly higher severity score compared with that of unenhanced scan (P < 0.05), while portal phase and dual phase scan showed no significant difference each other. The trend was similar regarding pancreatic inflammation and extrapancreatic complications, in which contrast enhanced scans showed significantly higher score compared with those of unenhanced scan, while no significant difference was observed between portal phase scan and dual phase scan. In pancreatic necrosis

  19. Imaging of Blood Flow in Cerebral Arteries with Dynamic Helical Computed Tomography Angiography (DHCTA) Using a 64-Row CT Scanner

    Energy Technology Data Exchange (ETDEWEB)

    Pekkola, J.; Kangasniemi, M. (Helsinki Medical Imaging Center, Helsinki Univ. Central Hospital, Helsinki (Finland))

    2009-08-15

    Background: Cerebral computed tomography angiography (CTA) depicts a structural image of intracranial arteries without providing much time-resolved information on blood flow dynamics. Current CT technology allows obtaining of rapidly repeated helical scans during the arterial contrast filling phase after an intravenous contrast injection. Purpose: To report our experience on dynamic CT imaging in determining the direction of contrast filling within proximal intracranial arteries of operated cerebral artery aneurysm patients. Such dynamic information can help detect vascular occlusion or severe spasm. The method is here referred to as dynamic helical CT angiography (DHCTA). Material and Methods: We retrospectively collected image and related technical data for 23 patients who underwent DHCTA and CTA during their first postoperative day after cerebral artery aneurysm surgery. For DHCTA, we had helically scanned a 4-cm tissue volume three times in succession with a 64-row CT scanner at intervals of 2.6 s during arterial contrast filling after an intravenous contrast injection. We assessed how well DHCTA succeeded in demonstrating the direction of contrast filling in the proximal intracranial arteries, evaluated clinically relevant structural information provided by DHCTA and CTA, and compared radiation doses for the two methods. Results: For 21 patients, DHCTA outlined the direction of contrast filling in proximal intracranial arteries. As to arterial spasm and residual filling of the operated aneurysm, CTA and DHCTA gave similar information. Radiation doses were higher (P<0.000001) for DHCTA than for CTA at 120 kV tube voltage. At 100 kV, the difference was smaller, but doses for DHCTA still exceeded (P<0.05) those for CTA. Conclusion: DHCTA gave dynamic information unobtainable with CTA and could prove useful in selected clinical settings

  20. Lung cancer perfusion at multi-detector row CT: reproducibility of whole tumor quantitative measurements.

    Science.gov (United States)

    Ng, Quan-Sing; Goh, Vicky; Fichte, Heinz; Klotz, Ernst; Fernie, Pat; Saunders, Michele I; Hoskin, Peter J; Padhani, Anwar R

    2006-05-01

    Institutional review board approval and informed consent were obtained for this study. The aim of the study was to prospectively assess, in patients with lung cancer, the reproducibility of a quantitative whole tumor perfusion computed tomographic (CT) technique. Paired CT studies were performed in 10 patients (eight men, two women; mean age, 66 years) with lung cancer. Whole tumor permeability and blood volume were measured, and reproducibility was evaluated by using Bland-Altman statistics. Coefficient of variation of 9.49% for permeability and 26.31% for blood volume and inter- and intraobserver variability ranging between 3.30% and 6.34% indicate reliable assessment with this whole tumor technique.

  1. Accuracy of multidetector-row CT in diagnosing lymph node metastasis in patients with gastric cancer

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Takuro; Kurokawa, Yukinori; Takiguchi, Shuji; Miyazaki, Yasuhiro; Takahashi, Tsuyoshi; Yamasaki, Makoto; Miyata, Hiroshi; Nakajima, Kiyokazu; Mori, Masaki; Doki, Yuichiro [Osaka University, Graduate School of Medicine, Department of Gastroenterological Surgery, Suita, Osaka (Japan)

    2014-08-06

    The purpose of this study was to determine the optimal cut-off value of lymph node size for diagnosing metastasis in gastric cancer with multidetector-row computed tomography (MDCT) after categorizing perigastric lymph nodes into three regions. The study included 90 gastric cancer patients who underwent gastrectomy. The long-axis diameter (LAD) and short-axis diameter (SAD) of all visualized lymph nodes were measured with transverse MDCT images. The locations of lymph nodes were categorized into three regions: lesser curvature, greater curvature, and suprapancreatic. The diagnostic value of lymph node metastasis was assessed with receiver operating characteristic (ROC) analysis. The area under the curve was larger for SAD than LAD in all groups. The optimal cut-off values of SAD were determined as follows: overall, 9 mm; differentiated type, 9 mm; undifferentiated type, 8 mm; lesser curvature region, 7 mm; greater curvature region, 6 mm; and suprapancreatic region, 9 mm. The diagnostic accuracies for lymph node metastasis using individual cut-off values were 71.1 % based on histological type and 76.6 % based on region of lymph node location. The diagnostic accuracy of lymph node metastasis in gastric cancer was improved by using individual cut-off values for each lymph node region. (orig.)

  2. Radiation dose assessment in a 320-detector-row CT scanner used in cardiac imaging

    Energy Technology Data Exchange (ETDEWEB)

    Goma, Carles; Ruiz, Agustin; Jornet, Nuria; Latorre, Artur; Pallerol, Rosa M.; Carrasco, Pablo; Eudaldo, Teresa; Ribas, Montserrat [Servei de Radiofisica i Radioproteccio, Hospital de la Santa Creu i Sant Pau, Sant Antoni Maria Claret 167, 08025 Barcelona (Spain)

    2011-03-15

    Purpose: In the present era of cone-beam CT scanners, the use of the standardized CTDI{sub 100} as a surrogate of the idealized CTDI is strongly discouraged and, consequently, so should be the use of the dose-length product (DLP) as an estimate of the total energy imparted to the patient. However, the DLP is still widely used as a reference quantity to normalize the effective dose for a given scan protocol mainly because the CTDI{sub 100} is an easy-to-measure quantity. The aim of this article is therefore to describe a method for radiation dose assessment in large cone-beam single axial scans, which leads to a straightforward estimation of the total energy imparted to the patient. The authors developed a method accessible to all medical physicists and easy to implement in clinical practice in an attempt to update the bridge between CT dosimetry and the estimation of the effective dose. Methods: The authors used commercially available material and a simple mathematical model. The method described herein is based on the dosimetry paradigm introduced by the AAPM Task Group 111. It consists of measuring the dose profiles at the center and the periphery of a long body phantom with a commercial solid-state detector. A weighted dose profile is then calculated from these measurements. To calculate the CT dosimetric quantities analytically, a Gaussian function was fitted to the dose profile data. Furthermore, the Gaussian model has the power to condense the z-axis information of the dose profile in two parameters: The single-scan central dose, f(0), and the width of the profile, {sigma}. To check the energy dependence of the solid-state detector, the authors compared the dose profiles to measurements made with a small volume ion chamber. To validate the overall method, the authors compared the CTDI{sub 100} calculated analytically to the measurement made with a 100 mm pencil ion chamber. Results: For the central and weighted dose profiles, the authors found a good

  3. Prospective ECG-gated 320-row CT angiography of the whole aorta and coronary arteries

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yu.; Fan, Zhanming; Xu, Lei; Yang, Lin; Xin, Haiyan; Zhang, Nan [Capital Medical University, Department of Radiology, Beijing An Zhen Hospital, Beijing (China); Capital Medical University, Ministry of Education, The Key Laboratory of Remodeling-Related Cardiovascular Diseases, Beijing An Zhen Hospital, Beijing (China); Zhang, Zhaoqi [Capital Medical University, Department of Radiology, Beijing An Zhen Hospital, Beijing (China)

    2012-11-15

    To investigate the feasibility of using a prospective ECG-gated wide-volume protocol in CT angiography (CTA) of the whole aorta and coronary arteries (CA). A total of 61 consecutive patients with suspected acute aortic diseases underwent CTA of the whole aorta using a prospective ECG-gated wide-volume CT protocol without heart rate (HR) control. The exposure window was set at 40-50 % of R-R interval (HR {>=}70 bpm) or 70-80 % of R-R interval (HR <70 bpm) in a single heartbeat. The image quality of the ascending aorta, aortic valve and CA was evaluated for motion artefacts. The mean attenuation was measured at different levels of the aorta. The radiation dose and contrast medium volume were recorded. All of the examinations were performed successfully. The image quality was acceptable in the ascending aorta, aortic valve (100 %) and CA (94.4 %). The mean radiation dose was 18.42 {+-} 5.02 mSv. Of 61 patients, 14 were diagnosed with aortic aneurysm and 35 were diagnosed with aortic dissection or intramural haematoma. Coronary artery stenosis was detected in 12 patients. For patients with aortic diseases, CTA of the whole aorta using a prospective ECG-gated wide-volume protocol has the potential to provide additional information about the CA and aortic valve with lower radiation exposure. (orig.)

  4. Are pancreatic calcifications specific for the diagnosis of chronic pancreatitis? A multidetector-row CT analysis

    Energy Technology Data Exchange (ETDEWEB)

    Campisi, A. [Department of Radiology, University of Palermo, via del Vespro 127, 90127 Palermo (Italy); Brancatelli, G. [Department of Radiology, University of Palermo, via del Vespro 127, 90127 Palermo (Italy); Department of Radiology, University of Pittsburgh School of Medicine, 200 Lothrop street, 15213, Pittsburgh, PA (United States); Radiology Unit, La Maddalena hospital, 90146, Palermo (Italy)], E-mail: gbranca@yahoo.com; Vullierme, M.-P.; Levy, P.; Ruzniewski, P. [Universite Paris 7 Denis Diderot, Paris, F-75018 (France); AP-HP, Hopital Beaujon, Department of Radiology, Clichy F-92100 (France); Vilgrain, V. [Universite Paris 7 Denis Diderot, Paris, F-75018 (France); AP-HP, Hopital Beaujon, Department of Radiology, Clichy F-92100 (France); INSERM, U773, Centre de recherche biomedicale Bichat-Beaujon, CRB3, Paris F-75018 (France)

    2009-09-15

    Aim: To retrospectively establish the most frequently encountered diagnoses in patients with pancreatic calcifications and to investigate whether the association of certain findings could be helpful for diagnosis. Materials and methods: One hundred and three patients were included in the study. The location and distribution of calcifications; presence, nature, and enhancement pattern of pancreatic lesions; pancreatic atrophy and ductal dilatation were recorded. Differences between patients with chronic pancreatitis and patients with other entities were compared by using Fisher's exact test. Results: Patients had chronic pancreatitis (n = 70), neuroendocrine tumours (n = 14), intraductal papillary mucinous neoplasm (n = 11), pancreatic adenocarcinoma (n = 4), serous cystadenoma (n = 4). Four CT findings had a specificity of over 60% for the diagnosis of chronic pancreatitis: parenchymal calcifications, intraductal calcifications, parenchymal atrophy, and cystic lesions. When at least two of these four criteria were used in combination, 54 of 70 (77%) patients with chronic pancreatitis could be identified, but only 17 of 33 (51%) patients with other diseases. When at least three of these four criteria were present, a specificity of 79% for the diagnosis of chronic pancreatitis was achieved. Conclusion: Certain findings are noted more often in chronic pancreatitis than in other pancreatic diseases. The presence of a combination of CT findings can suggest chronic pancreatitis and be helpful in diagnosis.

  5. Study of optimal exposure windows using 320-Detector rows dynamic volume CT

    Directory of Open Access Journals (Sweden)

    Gang Sun

    2010-12-01

    Full Text Available Gang Sun1, Min Li1, Li Li1, Guo-ying Li1, Zhi-wei Jing21Departments of Medical Imaging, 2Medical Statistics, Jinan Military General Hospital, Shandong Province, ChinaAbstract: The purpose of this study was to determine the optimal electrocardiographic (ECG pulsing windows and evaluate the effect on reduced dose and accuracy using 320-detector rows dynamic volume computed tomography (DVCT. A total of 170 patients were prospectively studied. The optimal reconstruction windows were analyzed in 76 patients scanned using retrospective ECG gating. Forty-seven patients were scanned by the predicted triggering windows. The optimal positions of exposure intervals according to different heart rates were evaluated. Optimal image quality, radiation dose, and diagnostic accuracy were then investigated by applying optimal triggering windows. The optimal ECG pulsing windows were determined as follows: when heart rate was <70 beats per minute, the exposure windows should be preset at 60%–80%; for a heart rate 70–90 beats per minute at 70%–90%; and for a heart rate ≥90 beats per minute at 30%–50%. The radiation dose for patients scanned with prospective ECG gating was significantly lower (5.9 versus 12.9 mSv, P < 0.001. However, because two or three heart beats were needed when heart rate was >70 beats per minute, the radiation dose increased with increasing heart rate for both retrospective and prospective ECG gating (r = 0.64, P < 0.001 and r = 0.59, P < 0.001, respectively. On the basis of a per segment analysis, overall sensitivity was 98.0% (49/50, specificity was 99.2% (602/607, the positive predictive value was 90.7% (49/54, and the negative predictive value was 99.8% (602/603. In conclusion, DVCT has the potential to provide high image quality across a wide range of heart rates using an optimized ECG pulsing window. However, it is recommended to control heart rate below 70 beats per minute, if possible, to decrease the radiation dose

  6. How accurate is unenhanced multidetector-row CT (MDCT) for localization of renal calculi?

    Energy Technology Data Exchange (ETDEWEB)

    Goetschi, Stefan, E-mail: goetschi@gmx.net [Institute of Radiology, Triemli Hospital, Birmensdorferstrasse 497, 8063 Zuerich (Switzerland); Umbehr, Martin, E-mail: martin.umbehr@triemli.ch [Urology Clinic, Department of Surgery, Triemli Hospital, Birmensdorferstrasse 497, 8063 Zuerich (Switzerland); Ullrich, Stephan, E-mail: stephan.ullrich@triemli.ch [Institute of Radiology, Triemli Hospital, Birmensdorferstrasse 497, 8063 Zuerich (Switzerland); Glenck, Michael, E-mail: michael.glenck@triemli.ch [Institute of Radiology, Triemli Hospital, Birmensdorferstrasse 497, 8063 Zuerich (Switzerland); Suter, Stefan, E-mail: stefan.suter@triemli.ch [Urology Clinic, Department of Surgery, Triemli Hospital, Birmensdorferstrasse 497, 8063 Zuerich (Switzerland); Weishaupt, Dominik, E-mail: dominik.weishaupt@triemli.ch [Institute of Radiology, Triemli Hospital, Birmensdorferstrasse 497, 8063 Zuerich (Switzerland)

    2012-11-15

    Purpose: To investigate the correlation between unenhanced MDCT and intraoperative findings with regard to the exact anatomical location of renal calculi. Design, setting, and participants: Fifty-nine patients who underwent unenhanced MDCT for suspected urinary stone disease, and who underwent subsequent flexible ureterorenoscopy (URS) as treatment of nephrolithiasis were included in this retrospective study. All MDCT data sets were independently reviewed by three observers with different degrees of experience in reading CT. Each observer was asked to indicate presence and exact anatomical location of any calcification within pyelocaliceal system, renal papilla or renal cortex. Results were compared to intraoperative findings which have been defined as standard of reference. Calculi not described at surgery, but present on MDCT data were counted as renal cortex calcifications. Results: Overall 166 calculi in 59 kidneys have been detected on MDCT, 100 (60.2%) were located in the pyelocaliceal system and 66 (39.8%) in the renal parenchyma. Of the 100 pyelocaliceal calculi, 84 (84%) were correctly located on CT data sets by observer 1, 62 (62%) by observer 2, and 71 (71%) by observer 3. Sensitivity/specificity was 90-94% and 50-100% if only pyelocaliceal calculi measuring >4 mm in size were considered. For pyelocaliceal calculi {<=}4 mm in size diagnostic performance of MDCT was inferior. Conclusion: Compared to flexible URS, unenhanced MDCT is accurate for distinction between pyelocaliceal calculi and renal parenchyma calcifications if renal calculi are >4 mm in size. For smaller renal calculi, unenhanced MDCT is less accurate and distinction between a pyelocaliceal calculus and renal parenchyma calcification is difficult.

  7. Brain volume perfusion CT performed with 128-detector row CT system in patients with cerebral gliomas: A feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Xyda, Argyro [University Hospital of Goettingen, Department of Neuroradiology, Georg-August University, Goettingen (Germany); University Hospital of Heraklion, Department of Radiology, Crete (Greece); Haberland, Ulrike; Klotz, Ernst [Computed Tomography, Siemens AG Healthcare Sector, Forchheim (Germany); Bock, Hans Christoph [University Hospital of Goettingen, Department of Neurosurgery, Georg-August University, Goettingen (Germany); Jung, Klaus [University Hospital of Goettingen, Department of Medical Statistics, Georg-August University, Goettingen (Germany); Knauth, Michael; Schramm, Ramona; Psychogios, Marios Nikos; Schramm, Peter [University Hospital of Goettingen, Department of Neuroradiology, Georg-August University, Goettingen (Germany); Erb, Gunter [Bracco Imaging Deutschland GmbH, Konstanz (Germany)

    2011-09-15

    Validation of the feasibility and efficacy of volume perfusion computed tomography (VPCT) in the preoperative assessment of cerebral gliomas by applying a 128-slice CT covering the entire tumour. Forty-six patients (25 men, 21 women; mean age 52.8 years) with cerebral gliomas were evaluated with VPCT. Two readers independently evaluated VPCT data, drawing volumes of interest (VOIs) around the tumour according to maximum intensity projection volumes, which were mapped automatically onto the cerebral blood volume (CBV), flow (CBF) and permeability (Ktrans) perfusion datasets. As control, a second VOI was placed in the contralateral healthy cortex. Correlation among perfusion parameters, tumour grade, hemisphere and VOIs was assessed. The diagnostic power of perfusion parameters was analysed by receiver operating characteristics curve analyses. VPCT was feasible in the assessment of the entire tumour extent. Mean values of Ktrans, CBV, CBF in high-grade gliomas were significantly higher compared with low-grade (p < 0.01). Ktrans demonstrated the highest diagnostic (97% sensitivity), positive (100%) and negative (94%) prognostic values. VPCT was feasible in all subjects. All areas of different perfusion characteristics are depicted and quantified in colour-coded 3D maps. The derived parameters correlate well with tumour histopathology, differentiating low- from high-grade gliomas. (orig.)

  8. Detection and localization of acute upper and lower gastrointestinal (GI) bleeding with arterial phase multi-detector row helical CT

    Energy Technology Data Exchange (ETDEWEB)

    Jaeckle, T.; Stuber, G.; Hoffmann, M.H.K.; Jeltsch, M.; Schmitz, B.L.; Aschoff, A.J. [University Hospital of Ulm, Diagnostic and Interventional Radiology, Ulm (Germany)

    2008-07-15

    The purpose of this study was to evaluate the accuracy of multi-detector row helical CT (MDCT) for detection and localization of acute upper and lower gastrointestinal (GI) hemorrhage or intraperitoneal bleeding. Thirty-six consecutive patients with clinical signs of acute bleeding underwent biphasic (16- or 40-channel) MDCT. MDCT findings were correlated with endoscopy, angiography or surgery. Among the 36 patients evaluated, 26 were examined for GI bleeding and 10 for intraperitoneal hemorrhage. Confirmed sites of GI bleeding were the stomach (n = 5), duodenum (n = 5), small bowel (n = 6), large bowel (n = 8) and rectum (n = 2). The correct site of bleeding was identifiable on MDCT in 24/26 patients with GI bleeding. In 20 of these 24 patients, active CM extravasation was apparent during the exam. Among the ten patients with intraperitoneal hemorrhage, MDCT correctly identified the bleeding source in nine patients. Our findings suggest that fast and accurate localization of acute gastrointestinal and intraperitoneal bleeding is achievable on MDCT. (orig.)

  9. Technical note: Electrocardiogram electrode repositioning for 320-row coronary CT angiography in patients with regular and recurrent premature ventricular contractions.

    Science.gov (United States)

    Kondo, Takeshi; Matsutani, Hideyuki; Groarke, John; Takamura, Kazuhisa; Fujimoto, Shinichiro; Rybicki, Frank J; Kumamaru, Kanako K

    2014-01-01

    Arrhythmias can compromise image quality and increase radiation exposure during coronary CT angiography (CTA). However, premature ventricular contractions (PVCs) can occur in a predictable recurrent and regular pattern (ie, bigeminy, trigeminy, quadrigeminy) with post-PVC compensatory pauses. Electrocardiographic (ECG) electrode repositioning can achieve relative amplification of the R waves of PVCs compared with R waves of sinus beats. This technical note describes how simple ECG electrode repositioning, combined with an absolute-delay strategy, facilitated selective R waves of PVC ECG triggering of image acquisition in 6 patients with PVC bigeminy or quadrigeminy at the time of 320-row coronary CTA. All 6 studies were single heartbeat acquisition scans with excellent image quality and a median effective radiation dose of 2.9 mSv (interquartile range, 2.1-3.8 mSv). Standard ECG electrode positions used for 2 patients with PVC bigeminy undergoing coronary CTA were associated with an acquisition over 2 heartbeats and effective radiation doses of 6.8 and 10.3 mSv, respectively. In conclusion, ECG electrode repositioning combined with an absolute-delay strategy for regularly recurring PVCs, such as ventricular bigeminy, facilitates high image quality and lower radiation dose during coronary CTA. This simple and straightforward technique can be considered for all patients with regular and recurrent PVCs undergoing coronary CTA.

  10. Detection and localization of acute upper and lower gastrointestinal (GI) bleeding with arterial phase multi-detector row helical CT.

    Science.gov (United States)

    Jaeckle, T; Stuber, G; Hoffmann, M H K; Jeltsch, M; Schmitz, B L; Aschoff, A J

    2008-07-01

    The purpose of this study was to evaluate the accuracy of multi-detector row helical CT (MDCT) for detection and localization of acute upper and lower gastrointestinal (GI) hemorrhage or intraperitoneal bleeding. Thirty-six consecutive patients with clinical signs of acute bleeding underwent biphasic (16- or 40-channel) MDCT. MDCT findings were correlated with endoscopy, angiography or surgery. Among the 36 patients evaluated, 26 were examined for GI bleeding and 10 for intraperitoneal hemorrhage. Confirmed sites of GI bleeding were the stomach (n = 5), duodenum (n = 5), small bowel (n = 6), large bowel (n = 8) and rectum (n = 2). The correct site of bleeding was identifiable on MDCT in 24/26 patients with GI bleeding. In 20 of these 24 patients, active CM extravasation was apparent during the exam. Among the ten patients with intraperitoneal hemorrhage, MDCT correctly identified the bleeding source in nine patients. Our findings suggest that fast and accurate localization of acute gastrointestinal and intraperitoneal bleeding is achievable on MDCT.

  11. Integrated cardio-thoracic imaging with ECG-Gated 64-slice multidetector-row CT: initial findings in 133 patients

    Energy Technology Data Exchange (ETDEWEB)

    Salem, Randa; Remy-Jardin, Martine; Delhaye, Damien; Khalil, Chadi; Teisseire, Antoine; Remy, Jacques [Hospital Calmette, University Center of Lille, Department of Thoracic Imaging, LILLE cedex (France); Delannoy-Deken, Valerie; Duhamel, Alain [University of Lille, Place de Verdun, Department of Medical Statistics, LILLE cedex (France)

    2006-09-15

    The purpose of this study was to investigate the possibility of assessing the underlying respiratory disease as well as cardiac function during ECG-gated CT angiography of the chest with 64-slice multidetector-row CT (MDCT). One hundred thirty-three consecutive patients in sinus rhythm with known or suspected ventricular dysfunction underwent an ECG-gated CT angiographic examination of the chest without {beta}-blockers using the following parameters: (1) collimation: 32 x 0.6 mm with z-flying focal spot for the acquisition of 64 overlapping 0.6-mm slices (Sensation 64; Siemens); rotation time: 0.33 s; pitch: 0.3; 120 kV; 200 mAs; ECG-controlled dose modulation (ECG-pulsing) and (2) 120 ml of a 35% contrast agent. Data were reconstructed: (1) to evaluate the underlying respiratory disease (1-mm thick lung and mediastinal scans reconstructed at 55% of the R-R interval; i.e., ''morphologic scans'') and (2) to determine right (RVEF) and left (LVEF) ventricular ejection fractions (short-axis systolic and diastolic images; Argus software; i.e., ''functional scans''). The mean heart rate was 73 bpm (range: 42-120) and the mean scan time was 18.11{+-}2.67 s (range: 10-27). A total of 123 examinations (92%) had both lung and mediastinal images rated as diagnostic scans, whereas 10 examinations (8%) had non-diagnostic images altered by the presence of respiratory-motion artifacts (n=4) or cyclic artifacts related to the use of a pitch value of 0.3 in patients with a very low heart rate during data acquisition (n=6). Assessment of right and left ventricular function was achievable in 124 patients (93%, 95% CI: 88-97%). For these 124 examinations, the mean RVEF was 46.10% ({+-}9.5; range: 20-72) and the mean LVEF was 58.23% ({+-}10.88; range: 20-83). In the remaining nine patients, an imprecise segmentation of the right and left ventricular cavities was considered as a limiting factor for precise calculation of end-systolic and end

  12. Differentiation of a Femoral Hernia from an Inguinal Hernia on Isotropic Multidetector-Row CT (MDCT): the Benefit of Inguinal Ligament Coronal-Oblique Images

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Ju Hyun; Jang, Kyung Mi; Kim, Min Jeong; Ko, Ji Young; Koh, Sung Hye; Yie, Mi Yeon; Min, Kwang Seon; Kim, In Gyu [Hallym University Sacred Heart Hospital, Anyang (Korea, Republic of); Choi, Dong Il; Park, Yul Ri [Samsung Medical Center, Seoul (Korea, Republic of)

    2009-04-15

    This study was designed to evaluate the diagnostic value of the use of inguinal ligament coronal-oblique CT images in the differentiation of femoral hernias from inguinal hernias. A total of 32 patients (with 11 femoral hernias and 21 inguinal hernias) underwent CT imaging. All of the examinations were performed with a 16- multidetector row CT (MDCT) scanner with contrast enhancement, and transverse sections, coronal sections and coronal-oblique CT images were reformed along an imaginary inguinal ligament plane. Two independent observers retrospectively evaluated the CT scans. Image analysis was first performed with only transverse and coronal images. A second analysis was then performed with transverse, coronal and coronal- oblique images. The mean angle difference between coronal and coronal-oblique CT images was 8.0 degrees (range, 0-22 degrees). A radiologist correctly diagnosed the presence of a femoral hernia in nine (82%) of 11 patients and a radiology fellow correctly diagnosed the presence of a femoral hernia in seven (64%) of 11 patients in the first session. Both of the reviewers made the correct diagnosis in all patients in the second session. For inguinal hernias, both reviewers correctly diagnosed all patients during both sessions. The coronal-oblique CT images were the most valuable images for the evaluation of the relationship between hernias of the neck and inguinal ligament. Inguinal ligament coronal-oblique CT images can provide additional diagnostic value in the evaluation of groin hernias.

  13. Left ventricular functional parameters and geometric patterns in Korean adults on coronary CT angiography with a 320-detector-row CT scanner

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Eun Ju; Lee, Ki Nam; Cho, Won Jin; Kim, Young Dae [College of Medicine, Dong-A University, Busan (Korea, Republic of); Shin, Kyung Min; Lim, Jae Kwang; Lee, Jong Min [Dept. of Radiology, Kyungpook National University, Daegu (Korea, Republic of)

    2017-08-01

    To assess the normal reference values of left ventricle (LV) functional parameters in Korean adults on coronary CT angiography (CCTA) with a 320-detector-row CT scanner, and to analyze sex-related differences and correlations with various clinical characteristics. This study retrospectively enrolled 172 subjects (107 men and 65 women; age, 58 ± 10.9 years; body surface area [BSA], 1.75 ± 0.2 m{sup 2}) who underwent CCTA without any prior history of cardiac disease. The following parameters were measured by post-processing the CT data: LV volume, LV functional parameters (ejection fraction, stroke volume, cardiac output, etc.), LV myocardial mass, LV inner diameter, and LV myocardial thickness (including septal wall thickness [SWT], posterior wall thickness [PWT], and relative wall thickness [RWT = 2 × PWT / LV inner diameter]). All of the functional or volumetric parameters were normalized using the BSA. The general characteristics and co-morbidities for the enrolled subjects were recorded, and the correlations between these factors and the LV parameters were then evaluated. The LV myocardial thickness (SWT, 1.08 ± 0.18 cm vs. 0.90 ± 0.17 cm, p < 0.001; PWT, 0.91 ± 0.15 cm vs. 0.78 ± 0.10 cm, p < 0.001; RWT, 0.38 ± 0.08 cm vs. 0.33 ± 0.05 cm, p < 0.001), LV volume (LV end-diastolic volume, 112.9 ± 26.1 mL vs. 98.2 ± 21.0 mL, p < 0.001; LV end-systolic volume, 41.7 ± 14.7 mL vs. 33.7 ± 12.2 mL, p = 0.001) and mass (145.0 ± 29.1 g vs. 107.9 ± 20.0 g, p < 0.001) were significantly greater in men than in women. However, these differences were not significant after normalization using BSA, except for the LV mass (LV mass index, 79.6 ± 14.0 g/m{sup 2} vs. 66.2 ± 11.0 g/m{sup 2},p < 0.001). The cardiac output and ejection fraction were not significantly different between the men and women (cardiac output, 4.3 ± 1.0 L/min vs. 4.2 ± 0.9 L/min, p = 0.452; ejection fraction, 63.4 ± 7.7% vs. 66.4 ± 7.6%, p = 0.079). Most of the LV parameters were

  14. Influence of 320-detector-row volume scanning and AAPM report 111 CT dosimetry metrics on size-specific dose estimate: a Monte Carlo study.

    Science.gov (United States)

    Haba, Tomonobu; Koyama, Shuji; Kinomura, Yutaka; Ida, Yoshihiro; Kobayashi, Masanao

    2016-09-01

    The American Association of Physicists in Medicine (AAPM) task group 204 has recommended the use of size-dependent conversion factors to calculate size-specific dose estimate (SSDE) values from volume computed tomography dose index (CTDIvol) values. However, these conversion factors do not consider the effects of 320-detector-row volume computed tomography (CT) examinations or the new CT dosimetry metrics proposed by AAPM task group 111. This study aims to investigate the influence of these examinations and metrics on the conversion factors reported by AAPM task group 204, using Monte Carlo simulations. Simulations were performed modelling a Toshiba Aquilion ONE CT scanner, in order to compute dose values in water for cylindrical phantoms with 8-40-cm diameters at 2-cm intervals for each scanning parameter (tube voltage, bow-tie filter, longitudinal beam width). Then, the conversion factors were obtained by applying exponential regression analysis between the dose values for a given phantom diameter and the phantom diameter combined with various scanning parameters. The conversion factors for each scanning method (helical, axial, or volume scanning) and CT dosimetry method (i.e., the CTDI100 method or the AAPM task group 111 method) were in agreement with those reported by AAPM task group 204, within a percentage error of 14.2 % for phantom diameters ≥11.2 cm. The results obtained in this study indicate that the conversion factors previously presented by AAPM task group 204 can be used to provide appropriate SSDE values for 320-detector-row volume CT examinations and the CT dosimetry metrics proposed by the AAPM task group 111.

  15. Estudio vascular renal por TC multidetector de 64 canales 64-Multidetector row CT for the Renal Vascular Study

    Directory of Open Access Journals (Sweden)

    Daniela Stoisa

    2009-03-01

    Full Text Available Objetivo: Mostrar las diversas variantes anatómicas vasculares tanto arteriales como venosas en el estudio angiográfico renal por tomografìa computada multidetector (TCMD de 64 canales, dada su implicancia en un eventual planeamiento quirúrgico. Material y métodos: Evaluamos retrospectivamente 26 estudios realizados con tomógrafo Philips Brilliance de 64 canales. Se obtuvieron secuencias sin contraste y postcontraste e.v. en fases arterial y venosa, administrado con bomba inyectora doble cabezal. Para una fase arterial apropiada se utilizó técnica de bolus track. Las imágenes fueron posteriormente procesadas en Workstation Philips Brilliance 190P en un tiempo promedio de 30 minutos y reconstruidas con técnicas MIP y volumétrica. Resultados: Dentro de las variantes anatómicas arteriales, encontramos: bifurcaciones prehiliares (n=3, arterias accesorias (n=4 y arterias polares (n=9. Dentro de las variantes venosas fueron halladas: venas renales múltiples (n=5, venas circumaórticas (n=2, retroaórticas (n=2 y vena tributaria lumbar prominente (n=1. Conclusión: El estudio vascular renal adquiere importancia en el planeamiento quirúrgico en casos de nefrectomías parciales, laparoscópicas y en el transplante renal. Esto otorga suma utilidad al estudio de TCMD de 64 canales por su eficacia diagnóstica, dada la alta calidad de las reconstrucciones obtenidas, llegando a igualar a la angiografía digital, sin ser un método invasivo.Purpose: To show the wide range of anatomical vascular variants, arterial and venous, that can be seen in the angiographic renal study using 64-multidetector-row computed tomography (64-MDCT, due to its importance in an eventual surgical planning. Material and Methods: We have evaluated retrospectively 26 studies that have been done using a 64 channels Philips Brilliance CT scanner. We have obtained non enhanced and both in arterial and venous enhanced sequences. For the injection of the contrast material we

  16. Computed tomography angiography of carotid and coronary artery via a single-bolus injection protocol: a feasibility study using 320-row multidetector CT

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, WeiGuo [The First Affiliated Hospital of Soochow University, Department of Radiology, SuZhou (China); Fudan University, Department of Radiology, Zhongshan Hospital, Shanghai (China); Jin, Hang; Chen, Gang; Chen, Wenfang; Gu, Junying; Zeng, Mengsu [Fudan University, Department of Radiology, Zhongshan Hospital, Shanghai (China)

    2014-07-15

    To investigate the feasibility of using a single-dose injection protocol in CT angiography (CTA) of the carotid and coronary artery with 320-row multidetector CT. A total of 82 consecutive patients with suspected carotid artery disease underwent an original CTA protocol aiming at capturing the extra-cranial carotid arteries and coronary arteries simultaneously using 320-row MDCT. The image quality, attenuation, and CNRs of the carotid and coronary arteries were assessed. The lag time (between two separated volumetric acquisitions) was compared between patients with and without cardiac venous opacification (CVO). The contrast medium volume and radiation dose were recorded. The image quality was 99.4 % diagnostic in carotid and 86.9 % in coronary artery segments. The mean attenuation of carotid and coronary arteries ranged from 462.2 Hu to 533.7 Hu, 415.9 Hu to 454.7 Hu respectively. The mean CNR of the carotid and coronary artery ranged from 15.8 to 18.9 and 17.7 to 20.4 respectively. The lag time in patients with and without CVO was 5.75 ± 1.64 s vs. 4.21 ± 1.14 s (p < 0.05). The mean radiation dose was 6.6 ± 4.1 mSv.The mean contrast media volume was 71.9 ± 9.1 ml. The carotid and coronary artery can be imaged simultaneously via our original single-dose injection CTA protocol using 320-row CT with adequate image quality. (orig.)

  17. Perfusion measurement of the whole upper abdomen of patients with and without liver diseases: Initial experience with 320-detector row CT

    Energy Technology Data Exchange (ETDEWEB)

    Kanda, Tomonori, E-mail: k_a@hotmail.co.jp [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunokicho, Chuoku, Kobe 650-0017 (Japan); Yoshikawa, Takeshi, E-mail: yoshikaw@med.kobe-u.ac.jp [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunokicho, Chuoku, Kobe 650-0017 (Japan); Ohno, Yoshiharu, E-mail: yosirad@kobe-u.ac.jp [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunokicho, Chuoku, Kobe 650-0017 (Japan); Fujisawa, Yasuko, E-mail: yasuko1.fujisawa@toshiba.co.jp [Toshiba Medical Systems Co., 1385 Shimoishigami, Otawara 324-0036 (Japan); Kanata, Naoki, E-mail: takikina12345@yahoo.co.jp [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunokicho, Chuoku, Kobe 650-0017 (Japan); Yamaguchi, Masato, E-mail: masato03310402@yahoo.co.jp [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunokicho, Chuoku, Kobe 650-0017 (Japan); Seo, Yasushi, E-mail: yseo@med.kobe-u.ac.jp [Division of Gastroenterology, Department of Internal Medicine, Kobe University Graduate, School of Medicine, 7-5-2 Kusunokicho, Chuoku, Kobe 650-0017 (Japan); Yano, Yoshihiko, E-mail: yanoyo@med.kobe-u.ac.jp [Division of Gastroenterology, Department of Internal Medicine, Kobe University Graduate, School of Medicine, 7-5-2 Kusunokicho, Chuoku, Kobe 650-0017 (Japan); Koyama, Hisanobu, E-mail: hkoyama@med.kobe-u.ac.jp [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunokicho, Chuoku, Kobe 650-0017 (Japan); Kitajima, Kazuhiro, E-mail: kazu10041976@yahoo.co.jp [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunokicho, Chuoku, Kobe 650-0017 (Japan); Takenaka, Daisuke, E-mail: daisuket@med.kobe-u.ac.jp [Department of Radiology, Kobe University Graduate School of Medicine, 7-5-2 Kusunokicho, Chuoku, Kobe 650-0017 (Japan); and others

    2012-10-15

    Objectives: To report initial experience of upper abdominal perfusion measurement with 320-detector row CT (CTP) for assessment of liver diseases and therapeutic effects. Materials and methods: Thirty-eight patients who were suspected of having a liver disease underwent CTP. There were two patients with liver metastases, two with hemangiomas, and four with cirrhosis (disease group). CTP was repeated for four patients with cirrhosis or hepatocellular carcinoma (HCC) after therapy. Hepatic arterial and portal perfusion (HAP and HPP) and arterial perfusion fraction (APF), and arterial perfusion (AP) of pancreas, spleen, stomach, and intra-portal HCC were calculated. For disease-free patients (normal group), the values were compared among liver segments and among pancreatic and gastric parts. The values were compared between groups and before and after therapy. Results: No significant differences were found in the normal group except between APFs for liver segments 3 and 5, and fundus and antrum. Mean HAP and APF for the disease group were significantly higher than for the normal group. APF increased after partial splenic embolization or creation of a transjugular intrahepatic portosystemic shunt. HPP increased and AP of intra-portal HCC decreased after successful radiotherapy. Conclusions: 320-Detector row CT makes it possible to conduct perfusion measurements of the whole upper abdomen. Our preliminary results suggested that estimated perfusion values have the potential to be used for evaluation of hepatic diseases and therapeutic effects.

  18. Using multidetector-row CT in neonates with complex congenital heart disease to replace diagnostic cardiac catheterization for anatomical investigation: initial experiences in technical and clinical feasibility

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Tain; Tsai, I.C.; Chen, Min-Chi [Taichung Veterans General Hospital, 407 Department of Radiology, Taichung (Taiwan); Medical College of Chung Shan Medical University, Faculty of Medicine, Taichung (Taiwan); National Yang Ming University School of Medicine, Department of Medicine, Taipei (Taiwan); Fu, Yun-Ching; Jan, Sheng-Lin [Taichung Veterans General Hospital, Department of Paediatrics, Taichung (Taiwan); National Yang-Ming University, Institute of Clinical Medicine, Taipei (Taiwan); Wang, Chung-Chi; Chang, Yen [Taichung Veterans General Hospital, Section of Cardiovascular Surgery, Department of Surgery, Taichung (Taiwan)

    2006-12-15

    Echocardiography is the first-line modality for the investigation of neonatal congenital heart disease. Diagnostic cardiac catheterization, which has a small but recognized risk, is usually performed if echocardiography fails to provide a confident evaluation of the lesions. To verify the technical and clinical feasibilities of replacing diagnostic cardiac catheterization with multidetector-row CT (MDCT) in neonatal complex congenital heart disease. Over a 1-year period we prospectively enrolled all neonates with complex congenital heart disease referred for diagnostic cardiac catheterization after initial assessment by echocardiography. MDCT was performed using a 40-detector-row CT scanner with dual syringe injection. A multidisciplinary congenital heart disease team evaluated the MDCT images and decided if further diagnostic cardiac catheterization was necessary. The accuracy of MDCT in detecting separate cardiovascular anomalies and bolus geometry of contrast enhancement were calculated. A total of 14 neonates were included in the study. No further diagnostic cardiac catheterization was needed in any neonate. The accuracy of MDCT in diagnosing separate cardiovascular anomalies was 98% (53/54) with only one atrial septal defect missed in a patient with coarctation syndrome. The average cardiovascular enhancement in evaluated chambers was 471 HU. No obvious beam-hardening artefact was observed. The technical and clinical feasibility of MDCT in complex congenital heart disease in neonates is confirmed. After initial assessment with echocardiography, MDCT could probably replace diagnostic cardiac catheterization for further anatomical clarification in neonates. (orig.)

  19. Assessment of image quality of 64-row Dual Source versus Single Source CT coronary angiography on heart rate: A phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Dikkers, R. [Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, P.O. Box 30001, 9700 RB Groningen (Netherlands)], E-mail: r.dikkers@rad.umcg.nl; Greuter, M.J.W. [Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, P.O. Box 30001, 9700 RB Groningen (Netherlands)], E-mail: m.j.w.greuter@rad.umcg.nl; Kristanto, W. [Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, P.O. Box 30001, 9700 RB Groningen (Netherlands)], E-mail: w.kristanto@rad.umcg.nl; Ooijen, P.M.A. van [Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, P.O. Box 30001, 9700 RB Groningen (Netherlands)], E-mail: p.m.a.van.ooyen@rad.umcg.nl; Sijens, P.E. [Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, P.O. Box 30001, 9700 RB Groningen (Netherlands)], E-mail: p.e.sijens@rad.umcg.nl; Willems, T.P. [Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, P.O. Box 30001, 9700 RB Groningen (Netherlands)], E-mail: t.p.willems@rad.umcg.nl; Oudkerk, M. [Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, P.O. Box 30001, 9700 RB Groningen (Netherlands)], E-mail: m.oudkerk@rad.umcg.nl

    2009-04-15

    Purpose: To assess the influence of temporal resolution on image quality of computed tomographic (CT) coronary angiography by comparing 64-row Dual Source CT (DSCT) and Single Source CT (SSCT) at different heart rates. Methods: An anthropomorphic moving heart phantom was scanned at rest, and at 50 beats per minute (bpm) up to 110 bpm, with intervals of 10 bpm. 3D volume rendered images and curved multi-planar reconstructions (MPRs) were acquired and image quality of the coronary arteries was rated on a 5-points scale (1 = poor image quality with many artefacts, 5 = excellent image quality) for each heart rate and each scanner by 3 observers. Paired sample t-test and Wilcoxon Signed Ranks test were used to assess clinically relevant differences between both modalities. Results: The mean image quality scores at 70, 100 and 110 bpm were significantly higher for DSCT compared to SSCT. The overall mean image quality scores for DSCT (4.2 {+-} 0.6) and SSCT (3.0 {+-} 1.1) also differed significantly (p < 0.001). Conclusion: These initial results show a clinically relevant overall higher image quality for DSCT compared to SSCT, especially at heart rates of 70, 100 and 110 bpm. With its comparatively high image quality and low radiation dose, DSCT appears to be the method of choice in CT coronary angiography at heart rates above 70 bpm.

  20. Diagnostic Value of 16-row CT Angiography in Aortic Dissection%16排CT血管成像对主动脉夹层的诊断价值

    Institute of Scientific and Technical Information of China (English)

    曹禹

    2012-01-01

    Objective: To evaluate the diagnostic value of 16-row angiography in aortic dissection. Methods:32 cases of patients recieved with aortic dissection from June.2010. to April.2012 were selected for the 16-row CT scan and combined with angiography processing method for diagnosis. Results: The classification of aortic dissection of this group cases as follows:9 cases for type I (28.1%),4 cases for type II (12.5%),19 cases for type III (59.4%). In the plain 16-row CT scan of this group cases,11 cases of patients with vascular intima calcification displace to the cavity larger than 5mm(34.3%). All cases of this group performed enhanced angiography, and showed tearing intimal flap, presented linear low density image, tomography presented an arc image,reconstructed two dimensional images presented a straight-line or spiral low density linear image. Conclusion: In the clinical diagnosis of aortic dissection patients,16-row angiography technique has a rapid, accurate and non-invasive advantage, and could be the preferred method for diagnosis.%目的探讨16排CT血管成像对主动脉夹层的诊断价值.方法选取本组2010年6月到2012年4月收治的主动脉夹层患者32例,均行16排CT扫描,并结合相关血管成像处理方法进行诊断.结果本组病例的主动脉夹层分型结果为:Ⅰ型9例(28.1%),Ⅱ型4例(12.5%),Ⅲ型19例(59.4%).在本组病例的16排CT平扫中,血管内膜钙化向腔内移位≥5mm者11例(34.3%).本组病例均行血管造影增强扫描,全部显示撕裂的内膜片,呈现线形低密度影,断层像上呈现弧形,二维重建像呈现直线状或螺旋状低密度线状影.结论在主动脉夹层患者的临床诊断中,16排CT血管成像技术的应用具有准确、快速、无创等优点,可以作为首选的诊断方法.

  1. Inter- and intrascanner variability of pulmonary nodule volumetry on low-dose 64-row CT : an anthropomorphic phantom study

    NARCIS (Netherlands)

    Xie, X.; Willemink, M. J.; Zhao, Y.; de Jong, P. A.; van Ooijen, P. M. A.; Oudkerk, M.; Greuter, M. J. W.; Vliegenthart, R.

    2013-01-01

    Objective: To assess inter- and intrascanner variability in volumetry of solid pulmonary nodules in an anthropomorphic thoracic phantom using low-dose CT. Methods: Five spherical solid artificial nodules [diameters 3, 5, 8, 10 and 12mm; CT density 1100 Hounsfield units (HU)] were randomly placed ins

  2. Multi-organ perfusion CT in the abdomen using a 320-detector row CT scanner: Preliminary results of perfusion changes in the liver, spleen, and pancreas of cirrhotic patients

    Energy Technology Data Exchange (ETDEWEB)

    Motosugi, Utaroh, E-mail: utaroh-motosugi@nifty.com [Department of Radiology, University of Yamanashi, 1110 Shimokato, Chuo-shi, Yamanashi (Japan); Ichikawa, Tomoaki, E-mail: ichikawa@yamanashi.ac.jp [Department of Radiology, University of Yamanashi, 1110 Shimokato, Chuo-shi, Yamanashi (Japan); Sou, Hironobu, E-mail: fffun0300@yahoo.ac.jp [Department of Radiology, University of Yamanashi, 1110 Shimokato, Chuo-shi, Yamanashi (Japan); Morisaka, Hiroyuki, E-mail: morisakahiroyuki@hotmail.co.jp [Department of Radiology, University of Yamanashi, 1110 Shimokato, Chuo-shi, Yamanashi (Japan); Sano, Katsuhiro, E-mail: snkthr@yahoo.co.jp [Department of Radiology, University of Yamanashi, 1110 Shimokato, Chuo-shi, Yamanashi (Japan); Araki, Tsutomu, E-mail: arakit@yamanashi.ac.jp [Department of Radiology, University of Yamanashi, 1110 Shimokato, Chuo-shi, Yamanashi (Japan)

    2012-10-15

    Purpose: To utilize 320-detector row CT in perfusion CT of multiple abdominal organs and to compare the tissue perfusion between patients with and without liver cirrhosis. Materials and methods: This study included 21 patients with cirrhosis and 20 without cirrhosis. The 320-detector row CT scanner enabled multi-organ perfusion CT without requiring the scanner table to be moved. Perfusion was calculated using the maximum slope model for the aorta, the portal vein, the right and left lobes of the liver, the head and body of the pancreas, the spleen, and the corpus and antrum of the stomach. Perfusion in each organ of patients with and without cirrhosis was compared. Results: Portal venous perfusion of the right and left lobes of the liver in patients with cirrhosis (117 and 100 mL min{sup −1} 100 mL{sup −1}, respectively) was significantly less than that in patients without cirrhosis (213 and 174 mL min{sup −1} 100 mL{sup −1}, respectively; p = 0.0081 and 0.0294, respectively). Arterial perfusion of the spleen (111 mL min{sup −1} 100 mL{sup −1}) and the body of the pancreas (112 mL min{sup −1} 100 mL{sup −1}) in patients with cirrhosis was also significantly decreased compared with that in patients without cirrhosis (spleen, 162 mL min{sup −1} 100 mL{sup −1}, p = 0.0020; body of pancreas, 133 mL min{sup −1} 100 mL{sup −1}, p = 0.0405). Conclusion: The results of the perfusion CT suggest that arterial perfusion of the spleen and the body of the pancreas, as well as portal perfusion of the liver, in cirrhotic patients was decreased compared with that in non-cirrhotic patients.

  3. Intra-individual comparison of patient acceptability of multidetector-row CT colonography and double-contrast barium enema

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, S.A. [Department of Intestinal Imaging, St Mark' s and Northwick Park Hospitals, London (United Kingdom)]. E-mail: csytaylor@yahoo.co.uk; Halligan, S. [Department of Intestinal Imaging, St Mark' s and Northwick Park Hospitals, London (United Kingdom); Burling, D. [Department of Intestinal Imaging, St Mark' s and Northwick Park Hospitals, London (United Kingdom); Bassett, P. [Department of Intestinal Imaging, St Mark' s and Northwick Park Hospitals, London (United Kingdom); Bartram, C.I. [Department of Intestinal Imaging, St Mark' s and Northwick Park Hospitals, London (United Kingdom)

    2005-02-01

    AIMS: To compare the subjective acceptability of CT colonography in comparison with barium enema in older symptomatic patients, and to ascertain preferences for future colonic investigation. MATERIALS AND METHODS: The study population comprised 78 persons aged 60 years or over with symptoms suggestive of colorectal neoplasia, who underwent CT colonography followed the same day by barium enema. A 25-point questionnaire was administered after each procedure and an additional follow-up questionnaire a week later. Responses were compared using Wilcoxon matched pairs testing, Mann-Whitney test statistics and binomial exact testing. RESULTS: Participants suffered less physical discomfort during CT colonography (p=0.03) and overall satisfaction was greater compared with barium enema (p=0.03). On follow-up, respondents reported significantly better tolerance of CT colonography (p=0.002), and were less prepared to undergo barium enema again (p<0.001). Of 52 subjects expressing an opinion, all preferred CT to barium enema. CONCLUSION: Patient satisfaction was higher with CT colonography than barium enema. CT colonography caused significantly less physical discomfort and was overwhelmingly preferred by patients.

  4. 320层容积CT心肌灌注成像对心肌灌注缺损的诊断价值%Detection of myocardial perfusion defect with 320-row volume CT myocardial perfusion imaging

    Institute of Scientific and Technical Information of China (English)

    张传臣; 张兆琪; 王蒨; 徐磊; 于薇; 焦健; 王瑞

    2012-01-01

    目的 探讨320层容积CT心肌灌注成像(CT-MPI)的可行性及其对心肌灌注缺损的诊断价值.方法 对14例经SPECT心肌灌注成像(SPECT-MPI)阳性的已知或可疑冠心病患者行静息和腺苷负荷320层容积CT-MPI检查,使用专用心肌灌注软件对CT-MPI进行分析.以心肌16节段标准分段方法(心尖除外)分别分析核素和容积CT-MPI的固定或可逆性灌注缺损.以SPECT-MPI为参考标准评价CT-MPI对心肌灌注缺损诊断的敏感度、特异度.结果 所有患者均成功完成320层容积CT-MPI.SPECT-MPI显示14例患者中共有39段心肌出现固定或可逆性灌注缺损,CT-MPI正确显示了其中12例患者的34段心肌灌注缺损.320层容积CT-MPI诊断心肌灌注缺损的敏感度、特异度分别为87.2%( 34/39)和91.4%(169/185).结论 320层容积CT-MPI对诊断心肌灌注缺损有较高的敏感度和特异度.%Objective To evaluate the feasibility of 320-row volume CT myocardial perfusion imaging (CT-MPI) in detecting myocardial perfusion defect.Methods Fourteen patients with positive single-positron emission computed tomography myocardial perfusion imaging (SPECT-MPI) findings underwent both rest and adenosine stress 320-row volume CT-MPI.Rest and stress CT perfusion images were analyzed by employing dedicated software in 320-row CT workstation.Both SPECT-MPI and CT-MPI were evaluated for fixed and reversible perfusion defects using a 16-segment model (apex was excluded).The sensitivity,specificity of 320-row volume CT-MPI in detecting myocardial perfusion defect were evaluated by taking SPECT-MPI as a reference standard.Results Both rest and stress 320-row volume CT-MPI were successfully performed in all patients.Thirty nine segments with fixed or reversible perfusion defects in all patients were depicted by SPECT-MPI,while 34 perfusion defects in 12 patients were identified by CT-MPI.The sensitivity,specificity of 320-row volume CT-MPI for detection of perfusion defects were 87.2

  5. Adult Moyamoya disease: 320-Multidetector row CT for evaluation of revascularization in STA–MCA bypasses surgery

    Energy Technology Data Exchange (ETDEWEB)

    Tian, Bing; Xu, Bing; Liu, Qi; Hao, Qiang; Lu, Jianping, E-mail: cjr.lujianping@vip.163.com

    2013-12-01

    Purpose: To evaluate the utility of 320-multidetector row whole-brain computed tomography perfusion (WBCTP) and whole-head subtracted dynamic angiography (WHSDCTA) for assessing the revascularization of blood flow after superficial temporal artery (STA) to middle cerebral artery (MCA) bypass surgery in adults with Moyamoya disease (MD) in the short and long term. Patients and methods: 320-multidetector row WBCTP and WHSDCTA were applied in 20 patients with MD before and after surgery (for an average of 3 days and 3 months). The bypass arteries were investigated using WHSDCTA and compared with DSA. The regions of interests (ROIs) in the surgical and mirror sides of the cerebral cortex were drawn on a Vitrea Workstation. Cerebral blood volume (CBV), time to peak (TTP), cerebral blood flow (CBF), mean transit time (MTT), and delay time were recorded. Preoperative and postoperative perfusion parameters in the MCA distribution were compared using the paired t-test. Results: WHSDCTA could clearly demonstrate 24 bypass arteries in 26 arteries for 20 patients, results which were in accordance with the results of digital subtraction angiography (DSA). When comparing preoperative values to those within 3 days after surgery, only TTP and delay time were significantly different (P < 0.05). Values of CBV, TTP, CBF, delay time, and MTT 3 months after surgery were significantly different (P < 0.05) from those of preoperative perfusion. Conclusion: These data suggest that 320-multidetector row WBCTP and WHSDCTA can be used to evaluate the revascularization of blood flow after STA–MCA bypass surgery in patients with MD in the short and long term.

  6. Sensitivity and accuracy of volumetry of pulmonary nodules on low-dose 16- and 64-row multi-detector CT: an anthropomorphic phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Xueqian; Zhao, Yingru; Ooijen, Peter M.A. van; Vliegenthart, Rozemarijn [University of Groningen, University Medical Center Groningen, Department of Radiology, EB44, P.O. Box 30.001, Groningen (Netherlands); University of Groningen, University Medical Center Groningen, Center for Medical Imaging-North East Netherlands, Department of Radiology, Groningen (Netherlands); Snijder, Roland A.; Greuter, Marcel J.W. [University of Groningen, University Medical Center Groningen, Department of Radiology, EB44, P.O. Box 30.001, Groningen (Netherlands); Jong, Pim A. de [University Medical Center Utrecht, Department of Radiology, Utrecht (Netherlands); Oudkerk, Matthijs [University of Groningen, University Medical Center Groningen, Center for Medical Imaging-North East Netherlands, Department of Radiology, Groningen (Netherlands); Bock, Geertruida H. de [University of Groningen, University Medical Center Groningen, Department of Epidemiology, Groningen (Netherlands)

    2013-01-15

    To assess the sensitivity of detection and accuracy of volumetry by manual and semi-automated quantification of artificial pulmonary nodules in an anthropomorphic thoracic phantom on low-dose CT. Fifteen artificial spherical nodules (diameter 3, 5, 8, 10 and 12 mm; CT densities -800, -630 and +100 HU) were randomly placed inside an anthropomorphic thoracic phantom. The phantom was examined on 16- and 64-row multidetector CT with a low-dose protocol. Two independent blinded observers screened for pulmonary nodules. Nodule diameter was measured manually, and volume calculated. For solid nodules (+100 HU), diameter and volume were also evaluated by semi-automated software. Differences in observed volumes between the manual and semi-automated method were evaluated by a t-test. Sensitivity was 100 % for all nodules of >5 mm and larger, 60-80 % for solid and 0-20 % for non-solid 3-mm nodules. No false-positive nodules but high inter-observer reliability and inter-technique correlation were found. Volume was underestimated manually by 24.1 {+-} 14.0 % for nodules of any density, and 26.4 {+-} 15.5 % for solid nodules, compared with 7.6 {+-} 8.5 % (P < 0.01) semi-automatically. In an anthropomorphic phantom study, the sensitivity of detection is 100 % for nodules of >5 mm in diameter. Semi-automated volumetry yielded more accurate nodule volumes than manual measurements. (orig.)

  7. Comparison of 16-row multislice CT angiography with conventional angiography for detection and evaluation of intracranial aneurysms

    Energy Technology Data Exchange (ETDEWEB)

    Donmez, Halil; Serifov, Elman; Kahriman, Guven [University of Erciyes, School of Medicine, Department of Radiology, Kayseri (Turkey); Mavili, Ertugrul, E-mail: ertmavili@yahoo.com [University of Erciyes, School of Medicine, Department of Radiology, Kayseri (Turkey); Durak, Ahmet Candan [University of Erciyes, School of Medicine, Department of Radiology, Kayseri (Turkey); Menkue, Ahmet [University of Erciyes, School of Medicine, Department of Neurosurgery, Kayseri (Turkey)

    2011-11-15

    Purpose: The aim of this study is to compare the diagnostic performance of 16-row computed tomographic angiography (MDCTA) with digital subtraction angiography (DSA) for the detection and characterization of intracranial aneurysms in patients with nontraumatic subarachnoid hemorrhages (SAH). Materials and methods: One-hundred and twelve consecutive patients with suspected intracranial aneurysm underwent both 16-row MDCTA and DSA. The MDCT angiograms were interpreted in a blinded fashion by using combination with VRI, MIP and MPR techniques. Sensitivity specificity and accuracy were calculated for the CTA and DSA. The results were compared with each other. The DSA reader's interpretation was accepted as the reference standard. Results: A total of 164 aneurysms were detected at DSA in 112 patients, no aneurysms were detected by DSA and MDCTA in 16 patients. Eight aneurysms were missed by MDCTA. The overall sensitivity, specificity, and accuracy of MDCTA on a per-aneurysm basis were 95.1%, 94.1%, and 95%, respectively. According to the size of the aneurysm less than 3 mm; sensitivity, specificity and diagnostic accuracy of MDCTA were 86.1%, 94.1%, 88.6%, respectively. Conclusion: This study suggests that MDCTA is equally as sensitive as DSA in the detection of intracranial aneurysms of greater than 3 mm, and it also reveals 100% detection rate for ruptured aneurysms.

  8. 急性脑梗死320排 CT 脑灌注成像分析%The analysis of whole-brain CT perfusion imaging with 320-detector row CT in acute cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    阮志兵; 段庆红

    2014-01-01

    Objective To explore the clinical value of whole-brain CT perfusion imaging with 320-detector row CT in early acute cerebral infarction.Methods The CTP parameters(CBF,CBV,MTT,TTP)and its pseudo color map of 25 patients with early acute cerebral infarction were retrospectively analysed and compared between infarction area,ischemic penumbra (IP)and the con-tralateral normal region.Results The abnormal perfusion area were found on CTP in 25 patients with early acute cerebral infarction. CTP showed cerebral blood flow (CBF)and cerebral blood volume (CBV)decreased significantly,mean transit time (MTT)short-ened significantly,time to peak (TTP)was significantly longer than those of the contralateral normal region in 7 cases of acute cere-bral infarct core.18 cases of IP lesions showed CBF decreased slightly,CBV increased slightly or maintain normal,MTT and TTP extension compared with contralateral.CBF,CBV,MTT,TTP values had significantly differences between infarct region and the contralateral corresponding normal region,between the infarct core area and IP of acute cerebral infarction (P 0.05)between IP region and the contralateral corresponding normal region,but showed a downward trend in blood flow.Parameter color maps of CTP could di-rectly,clearly and sensitively show abnormal changes region about cerebral blood flow.In particular,MTT and TTP maps shows ab-normal region clearer and sensitively.Follow-up 18 cases of IP,active lesions deduced in 6 cases,the lesions disappeared in 5 pa-tients (CT/ MRI showed no abnormal,and the clinical symptoms disappeared)after thrombolytic therapy,7 cases of MRI and CT scans confirmed infarction stove.Conclusion Whole-brain CTP with 320-detector row CT can early show the acute cerebral infarc-tion and its ischemic penumbra,it has significant important clinical value for early acute cerebral infarction.%目的:探讨320排 CT 全脑灌注成像(CTP)在早期急性脑梗死中的临床应用价值。方法回顾性分析25

  9. Evaluation of multiple trauma victims with 16-row multidetector CT (MDCT): a time analysis; Anwendung der 16-Zeilen-Mehrdetektor-CT in der Initialdiagnostik beim Polytrauma: Eine Zeitanalyse

    Energy Technology Data Exchange (ETDEWEB)

    Heyer, C.M.; Nicolas, V. [Bochum Univ. (Germany). Inst. fuer Diagnostische Radiologie, Interventionelle Radiologie und Nuklearmedizin; Rduch, G.J. [Bochum Univ. (Germany). Klinik fuer Chirurgie; Wick, M.; Muhr, G. [Bochum Univ. (Germany). Medizinische Klinik III, Pneumologie, Allergologie und Schlafmedizin; Bauer, T.T. [Berufsgenossenschaftliche Kliniken Bergmannsheil, Ruhr-Univ. Bochum (Germany)

    2005-12-15

    Purpose: Description and time analysis of a 16-row MDCT protocol in the evaluation of multiple trauma patients considering transport, time of scanning, patient positioning, image reconstruction, and image interpretation. Materials and methods: Between May and December 2004, 60 multiple trauma patients underwent 16-row MDCT (Sensation, Siemens, Erlangen, Germany). The protocol included serial scanning of the head, spiral scanning of the cervical spine and contrast-enhanced spiral scanning of the thorax/abdomen with multiplanar reformations (MPR) of the thoracic/lumbar spine and the pelvis. All time intervals including transport, patient positioning, scanning, duration of MPR, total time in the examination room, and time to first and final image interpretation were prospectively evaluated. Furthermore, patient characteristics, trauma profiles, and mortality rates were recorded. Results: 46 male and 14 female patients (mean age 43.6 years) were enrolled in the study. Time analysis of 16-row MDCT revealed the following results (mean time standard deviation): Emergency room treatment and transport 19.2{+-}6.7 min, patient positioning 16.5{+-}6.5 min, scan duration 8.0{+-}3.3 min, total time in examination room 24.5{+-}7.2 min, image reconstruction including MPR 32.0{+-}16.4 min, and time of first (16.4{+-}4.7 min) and final image interpretation (82.5{+-}30.4 min). Trauma profiles revealed thoracic injuries in 35/60 patients (58.3%), head injuries in 23/60 patients (38.3%), abdominal injuries in 15/60 patients (25.0%), injuries of the cervical (9/60 patients, 15.0%), thoracic (12/60 patients, 20.0%), and lumbar spine (19/60 patients, 31.7%), pelvic injuries in 13/60 patients (21.7%), and injuries of extremities in 39/60 patients (65.0%). The mortality rate was 21.7%. (orig.)

  10. Diagnosis of coronary artery disease. Current status of CT; Diagnostik der koronaren Herzkrankheit. Aktueller Stand der CT

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, Martin H.K.; Klass, O.; Brunner, H. [Klinik fuer Diagnostische und Interventionelle Radiologie, Unikliniken Ulm (Germany)

    2010-06-15

    Continuous technical innovations during the last years have established cardiac CT as a modality for noninvasive coronary angiography in clinical routine. 64 detector row generations and beyond have shown high diagnostic accuracy for obstructive stenosis detection in comparison to the standard of reference catheterization angiography. But the high radiation dose exposure associated with helical cardiac CT acquisition has sparked increasing concern in the medical community. The issue has been addressed with the newest releases of technology. Dose reduction by 80% and more is achieved with modified scan techniques rendering the method suitable for clinical routine. Symptomatic patients with an intermediate pre-test probability have been identified as the most suitable candidates for CT coronary angiography. Other appropriate indications include the rapid assessment of bypass grafts and suspected coronary anomalies. CT coronary angiography has been shown to be cost effective for the evaluation of patients with acute chest pain in the emergency department. But CT is able to provide more than coronary morphology, initial feasibility testing has shown that CT first-pass myocardial imaging can visualize perfusion defects with adenosine induced vasodilatation. Coronary morphology and functional perfusion studies have been shown to be complementary providing incremental diagnostic value over either technique alone. In the next few years a lot of comparison trials will establish the best suitable perfusion method (SPECT, MRI or CT) for hybrid imaging with CT coronary angiography. (orig.)

  11. Enhancement patterns of pancreatic adenocarcinoma on conventional dynamic multi-detector row CT: Correlation with angiogenesis and fibrosis

    Institute of Scientific and Technical Information of China (English)

    Yuki Hattori; Toshifumi Gabata; Osamu Matsui; Kentaro Mochizuki; Hirohisa Kitagawa; Masato Kayahara; Tetsuo Ohta; Yasuni Nakanuma

    2009-01-01

    AIM: To evaluate retrospectively the correlation between enhancement patterns on dynamic computed tomography (CT) and angiogenesis and fibrosis in pancreatic adenocarcinoma.METHODS: Twenty-three patients with pancreatic adenocarcinoma underwent dynamic CT and tumor resection. In addition to the absolute and relative enhanced value that was calculated by subtracting the attenuation value on pre-contrast from those on contrast-enhanced CT in each phase, we defined one parameter, "tumor-aorta enhancement ratio", which was calculated by dividing enhancement of pancreatic cancer by enhancement of abdominal aorta in each phase. These enhancement patterns were correlated with the level of vascular endothelial growth factor (VEGF), microvessel density (MVD), and extent of fibrosis.RESULTS: The absolute enhanced value in the arterial phase correlated with the level of VEGF and MVD (P = 0.047, P = 0.001). The relative enhanced value in arterial phase and tumor-aorta enhancement ratio (arterial) correlated with MVD (P = 0.003, P = 0.022). Tumor-aorta enhancement ratio (arterial) correlated negatively with the extent of fibrosis (P = 0.004). The tumors with greater MVD and higher expression of VEGF tended to show high enhancement in the arterial dominant phase. On the other hand, the tumors with a larger amount of fibrosis showed a negative correlation with the grade of enhancement during the arterial phase.CONCLUSION: Enhancement patterns on dynamic CT correlated with angiogenesis and may be modified by the extent of fibrosis.

  12. Quantification of myocardial blood flow using dynamic 320-row multi-detector CT as compared with {sup 15}O-H{sub 2}O PET

    Energy Technology Data Exchange (ETDEWEB)

    Kikuchi, Yasuka; Oyama-Manabe, Noriko; Kudo, Kohsuke [Hokkaido University Hospital, Department of Diagnostic and Interventional Radiology, Sapporo (Japan); Naya, Masanao [Hokkaido University Graduate School of Medicine, Department of Cardiovascular Medicine, Sapporo (Japan); Manabe, Osamu; Tomiyama, Yuuki; Tamaki, Nagara [Hokkaido University Graduate School of Medicine, Department of Nuclear Medicine, Sapporo (Japan); Sasaki, Tsukasa [Hokkaido University Hospital, Department of Radiology, Sapporo (Japan); Katoh, Chietsugu [Hokkaido University Faculty of Health Sciences, Sapporo (Japan); Shirato, Hiroki [Hokkaido University Graduate School of Medicine, Department of Radiation Medicine, Sapporo (Japan)

    2014-07-15

    This study introduces a method to calculate myocardium blood flow (MBF) and coronary flow reserve (CFR) using the relatively low-dose dynamic 320-row multi-detector computed tomography (MDCT), validates the method against {sup 15}O-H{sub 2}O positron-emission tomography (PET) and assesses the CFRs of coronary artery disease (CAD) patients. Thirty-two subjects underwent both dynamic CT perfusion (CTP) and PET perfusion imaging at rest and during pharmacological stress. In 12 normal subjects (pilot group), the calculation method for MBF and CFR was established. In the other 13 normal subjects (validation group), MBF and CFR obtained by dynamic CTP and PET were compared. Finally, the CFRs obtained by dynamic CTP and PET were compared between the validation group and CAD patients (n = 7). Correlation between MBF of MDCT and PET was strong (r = 0.95, P < 0.0001). CFR showed good correlation between dynamic CTP and PET (r = 0.67, P = 0.0126). CFR{sub CT} in the CAD group (2.3 ± 0.8) was significantly lower than that in the validation group (5.2 ± 1.8) (P = 0.0011). We established a method for measuring MBF and CFR with the relatively low-dose dynamic MDCT. Lower CFR was well demonstrated in CAD patients by dynamic CTP. (orig.)

  13. Prosthetic heart valve assessment with multidetector-row CT: imaging characteristics of 91 valves in 83 patients

    Energy Technology Data Exchange (ETDEWEB)

    Habets, Jesse; Mali, Willem P.T.M.; Budde, Ricardo P.J. [UMC Utrecht, Department of Radiology, P.O. Box 85500, E01.132, GA, Utrecht (Netherlands); Symersky, Petr [Onze Lieve Vrouwe Gasthuis, Department of Cardiothoracic Surgery, Amsterdam (Netherlands); Academic Medical Center Amsterdam, Department of Cardiothoracic Surgery, Amsterdam (Netherlands); Herwerden, Lex A. van [University Medical Center Utrecht, Department of Cardiothoracic Surgery, Utrecht (Netherlands); Mol, Bas A.J.M. de [Academic Medical Center Amsterdam, Department of Cardiothoracic Surgery, Amsterdam (Netherlands); Spijkerboer, Anje M. [Academic Medical Center Amsterdam, Department of Radiology, Amsterdam (Netherlands)

    2011-07-15

    Multidetector CT (MDCT) has shown potential for prosthetic heart valve (PHV) assessment. We assessed the image quality of different PHV types to determine which valves are suitable for MDCT evaluation. All ECG-gated CTs performed in our institutions since 2003 were reviewed for the presence of PHVs. After reconstruction in 3 specific PHV planes, image quality of the supravalvular, perivalvular, subvalvular and valvular regions was scored on a four-point scale (1 = non-diagnostic, 2 = moderate, 3 = good and 4 = excellent) by two independent observers. Eighty-four CT examinations (66 cardiac, 18 limited-dose aortic protocols) of 83 patients with a total of 91 PHVs in the aortic (n = 71), mitral (n = 17), pulmonary (n = 1) and tricuspid (n = 2) position were included. CT was performed on a 16-slice (n = 4), 64-slice (n = 28) or 256-slice (n = 52) MDCT system. Median image quality scores for the supra-, peri- and subvalvular regions and valvular detail were (3.5, 3.3, 3.5 and 3.5, respectively) for bileaflet PHV; (3.0, 3.0, 3.5 and 3.0, respectively) for Medtronic Hall PHV; (1.0, 1.0, 1.0 and 1.0, respectively) for Bjoerk-Shiley and Sorin monoleaflet PHV and (3.5, 3.5, 4.0 and 2.0 respectively) for biological PHV. Currently implanted PHVs have good image quality on MDCT and are suitable for MDCT evaluation. (orig.)

  14. Jejunal GIST causing acute massive gastrointestinal bleeding: role of multidetector row helical CT in the preoperative diagnosis and management.

    Science.gov (United States)

    Daldoul, Sami; Moussi, Amir; Triki, Wissem; Baraket, Rym Bennaceur; Zaouche, Abdeljelil

    2012-09-01

    In this report, we describe a 34-year-old man with a jejunal gastrointestinal stromal tumour (GIST) accompanied by an unusual severe haemorrhage. Because oesophagogastroduodenoscopy proved inconclusive in determining the source of the bleeding and also because of gradually dropping haemoglobin levels and persistence of the melena not allowing colonic preparation, colonoscopy was cancelled and a mesenteric angio-computed tomography (angio-CT) was deemed necessary. The results of this analysis showed a 5-cm heterogeneous mass located in the jejunal loop surrounded by abnormal arterial structures. This multidetector computed tomography (MDCT) appearance was highly suggestive of GIST. The patient then underwent an urgent laparotomy and, peroperative findings being compatible with angio-CT descriptions, a small-bowel resection was performed. The results of the histopathological examination confirmed the diagnosis of GIST. Angio-CT helps define the size of GIST as well as its range and location and can be used as the primary routine test for patients suffering from lower-GI bleeding.

  15. Early and Delayed Myocardial Enhancement in Myocardial Infarction Using Two-Phase Contrast-Enhanced Multidetector-Row CT

    Science.gov (United States)

    Kim, Young-Whan; Han, Seong-Wook; Seo, Joon-Beom

    2007-01-01

    Objective The purpose of this study was to describe the myocardial enhancement patterns in patients with myocardial infarction using two-phase contrast-enhanced multidetector-row computed tomography (MDCT). Materials and Methods Twenty-three patients with clinically proven myocardial infarction (17 acute myocardial infarction [AMI] and 6 chronic myocardial infarction [CMI]) were examined with two-phase contrast-enhanced ECG-gated MDCT. The presence, location, and patterns of myocardial enhancement on two-phase MDCT images were compared with infarcted myocardial territories determined by using electrocardiogram, echocardiography, thallium-201 single photon emission computed tomography, catheter and MDCT coronary angiography. Results After clinical assessment, the presence of myocardial infarctions were found in 27 territories (19 AMI and 8 CMI) of 23 patients. Early perfusion defects were observed in 30 territories of all 23 patients. Three territories not corresponding to a myocardial infarction were detected in three patients with AMI and were associated with artifacts. Fourteen of perfusion defects were in the left anterior descending artery territory, four in the left circumflex artery territory, and nine in the right coronary artery territory. Delayed enhancement was observed in 25 territories (17 AMI and 8 CMI) of 21 patients. Delayed enhancement patterns were variable. Transmural early perfusion defects (n =12) were closely associated with transmural late enhancement (n = 5) and subendocardial residual defect with subepicardial late enhancement (n = 5). Conclusion Myocardial infarction showed early perfusion defects and variable delayed enhancement patterns on two-phase contrast-enhanced MDCT. Delayed enhancement technique of MDCT could provide additional information of the location and extent of infarcted myocardium, and could be useful to plan appropriate therapeutic strategies in patients with AMI. PMID:17420626

  16. Early and Delayed Myocardial Enhancement in Myocardial Infarction Using Two-Phase Contrast-Enhanced Multidetector-Row CT

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Sung-Min; Kim, Young-Whan; Han, Seong-Wook [University of Keimyung College of Medicine, Dongsan Medical Center, Daegu (Korea, Republic of); Seo, Joon-Beom [University of Ulsan College of Medicine, Asan Medical Center, Seoul (Korea, Republic of)

    2007-04-15

    The purpose of this study was to describe the myocardial enhancement patterns in patients with myocardial infarction using two-phase contrast enhanced multidetector-row computed tomography (MDCT). Twenty-three patients with clinically proven myocardial infarction (17 acute myocardial infarction [AMI] and 6 chronic myocardial infarction [CMI]) were examined with two-phase contrast-enhanced ECG-gated MDCT. The presence, location, and patterns of myocardial enhancement on two phase MDCT images were compared with infarcted myocardial territories determined by using electrocardiogram, echocardiography, thallium-201 single photon emission computed tomography, catheter and MDCT coronary angiography. After clinical assessment, the presence of myocardial infarctions were found in 27 territories (19 AMI and 8 CMI) of 23 patients. Early perfusion defects were observed in 30 territories of all 23 patients. Three territories not corresponding to a myocardial infarction were detected in three patients with AMI and were associated with artifacts. Fourteen of perfusion defects were in the left anterior descending artery territory, four in the left circumflex artery territory, and nine in the right coronary artery territory. Delayed enhancement was observed in 25 territories (17 AMI and 8 CMI) of 21 patients. Delayed enhancement patterns were variable. Transmural early perfusion defects (n =12) were closely associated with transmural late enhancement (n = 5) and subendocardial residual defect with subepicardial late enhancement (n = 5). Myocardial infarction showed early perfusion defects and variable delayed enhancement patterns on two-phase contrast-enhanced MDCT. Delayed enhancement technique of MDCT could provide additional information of the location and extent of infarcted myocardium, and could be useful to plan appropriate therapeutic strategies in patients with AMI.

  17. Coronary artery anomalies: Assessment with electrocardiography-gate multidetector-row CT at a single center in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Yi, Bo Ram; Sun, Joo Sung; Yang, Hyoung Mo; Kang, Doo Kyoung [Ajou University School of Medicine, Suwon (Korea, Republic of)

    2015-04-15

    To determine the prevalence of coronary anomalies using coronary computed tomography angiography (CCTA) and to evaluate the relationship between coronary artery anomalies and chest pain. A total of 12676 patients underwent CCTA scans at our institution between December 2006 and April 2013 using a 64-slice CT and a 128-slice dual-source CT. We determined the prevalence of coronary artery anomalies according to the classification system proposed by Greenberg. The presence or absence of chest pain with each coronary artery anomaly was also evaluated. Coronary anomalies were found in 176 patients (1.39%) at our institute. Anomalies of origination, course, and termination were detected in 118 (0.93%), 28 (0.22%), and 30 (0.24%) patients, respectively. After the exclusion of 32 patients with combined heart disease, typical (n = 16; 11.1%) or atypical (n = 28; 19.4%) chest pain was present in 44 (30.6%) of the 144 patients at the time of diagnosis. The prevalence of coronary artery anomalies was 1.39% at our hospital. After the exclusion of patients with combined heart disease, 11.1% had typical chest pain at the time of diagnosis.

  18. Accuracy of hydro-multidetector row CT in the local T staging of oesophageal cancer compared to postoperative histopathological results

    Energy Technology Data Exchange (ETDEWEB)

    Ba-Ssalamah, Ahmed; Matzek, Wolfgang; Baroud, Susanne; Bastati, Nina; Weber, Michael; Herold, Christian J. [Medical University of Vienna, Department of Radiology, Vienna (Austria); Zacherl, Johannes; Schoppmann, Sebastian F. [Medical University of Vienna, Department of Radiology, Vienna (Austria); Medical University of Vienna, Department of Surgery, Vienna (Austria); Hejna, Michael [Medical University of Vienna, Department of Radiology, Vienna (Austria); Medical University of Vienna, Department of Oncology, Vienna (Austria); Wrba, Fritz [Medical University of Vienna, Department of Radiology, Vienna (Austria); Medical University of Vienna, Department of Pathology, Vienna (Austria); Gore, Richard M. [University of Chicago Pritzker School of Medicine, Department of Radiology, Chicago, IL (United States)

    2011-11-15

    To evaluate the accuracy of multidetector computed tomography with water filling (Hydro-MDCT) in the T-staging of patients with oesophageal cancer. There were 131 consecutive patients who were preoperatively and prospectively examined in the prone position on arterial phase contrast-enhanced MDCT, after ingestion of 1,000-1,500 ml tap water and effervescent granules. Two readers staged the local tumour growth (T-staging) independently. They assessed tumour location, size, presence of stenosis, and morphology of the outer border of the oesophageal wall and perioesophageal fat planes on CT. CT findings were compared with histopathological results from resected specimens. Data were analyzed using the SPSS statistical package. Both readers obtained a high sensitivity of 95% and a high positive predictive value of 96%. Accurate local staging was achieved in 76.3% and 68.7% for readers 1 and 2, respectively. Inter-reader agreement was excellent (weighted {kappa} value of 0.93 and un-weighted {kappa} of 0.89). Using the hydro-technique and applying specific assessment criteria, MDCT appears to be an accurate, non-invasive diagnostic tool for local tumour staging of oesophageal cancer. (orig.)

  19. Chronic thromboembolic pulmonary hypertension (CTEPH). Potential role of multidetector-row CT (MD-CT) and MR imaging in the diagnosis and differential diagnosis of the disease

    Energy Technology Data Exchange (ETDEWEB)

    Wirth, G.; Brueggemann, K.; Bostel, T.; Dueber, C.; Kreitner, K.F. [Universitaetsmedizin Mainz (Germany). Dept. of Radiology; Mayer, E. [Kerckhoff Hospital, Bad Nauheim (Germany). Dept. of Thoracic Surgery

    2014-08-15

    Chronic thromboembolic pulmonary hypertension (CTEPH) can be defined as pulmonary hypertension (resting mean pulmonary arterial pressure of 25 mm Hg or more determined at right heart catheterization) with persistent pulmonary perfusion defects. It is a rare, but underdiagnosed disease with estimated incidences ranging from 0.5% to 3.8% of patients after an acute pulmonary embolism (PE), and in up to 10% of those with a history of recurrent PE. CTEPH is the only form of pulmonary hypertension that can be surgically treated leading to normalization of pulmonary hemodynamics and exercise capacity in the vast majority of patients. The challenges for imaging in patients with suspected CTEPH are fourfold: the imaging modality should have a high diagnostic accuracy with regard to the presence of CTEPH and allow for differential diagnosis. It should enable detection of patients suitable for PEA with great certainty, and allow for quantification of PH by measuring pulmonary hemodynamics (mPAP and PVR), and finally, it can be used for therapy monitoring. This overview tries to elucidate the potential role of ECG-gated multidetector CT pulmonary angiography (MD-CTPA) and MR imaging, and summarizes the most important results that have been achieved so far. Generally speaking, ECG-gated MD-CTPA is superior to MR in the assessment of parenchymal and vascular pathologies of the lung, and allows for the assessment of cardiac structures. The implementation of iodine maps as a surrogate for lung perfusion enables functional assessment of lung perfusion by CT. MR imaging is the reference standard for the assessment of right heart function and lung perfusion, the latter delineating typical wedge-shaped perfusion defects in patients with CTEPH. New developments show that with MR techniques, an estimation of hemodynamic parameters like mean pulmonary arterial pressure and pulmonary vascular resistance will be possible. CT and MR imaging should be considered as complementary

  20. Feasibility of 320-row area detector CT coronary angiography using 40 mL of contrast material: assessment of image quality and diagnostic accuracy

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Rihyeon; Park, Eun-Ah; Lee, Whal; Chung, Jin Wook [Seoul National University Hospital, Department of Radiology, Seoul (Korea, Republic of)

    2016-11-15

    To assess the image quality and diagnostic accuracy of 320-row area detector CT (320-ADCT) coronary angiography using 40 mL of contrast material in comparison with 60-mL protocol. This retrospective study included 183 patients who underwent 320-ADCT coronary angiography using 40 mL of contrast and additional 183 sex- and body mass index-matched patients using 60 mL of contrast constituting the control group. Both groups used the same 5-mL/sec injection rate. Quantitative image quality measurements and diagnostic accuracies were calculated and compared. Mean attenuation and contrast-to-noise ratio (CNR) at the aorta and all coronary arteries were lower in the 40-mL group than in the 60-mL group (all, p < 0.05), except for the CNR at proximal coronary arteries at 100 kVp (p = 0.073). However, the proportion of coronary segments with vessel attenuation >250 HU was not different between groups (all, p > 0.05), except for distal coronary arteries at 80 kVp (p = 0.001). Furthermore, there were no differences in per-patient and per-segment diagnostic accuracies between the groups (all, p > 0.05). 320-ADCT coronary angiography using 40 mL of contrast showed image quality and diagnostic accuracy comparable to the 60-mL protocol, demonstrating the clinical feasibility of lowering the risk of contrast-induced nephropathy through contrast volume reduction. (orig.)

  1. The emerging role of multidetector row CT angiography in the diagnosis of cervical arterial dissection: preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Elijovich, Lucas [NYU Medical Center, Department of Neurology, New York, NY (United States); Kazmi, Khuram [NYU Medical Center, Department of Neurology, New York, NY (United States); NYU Medical Center, Department of Radiology, New York, NY (United States); Gauvrit, Jean Y. [NYU Medical Center, Department of Radiology, New York, NY (United States); Hopital Salengro, Department of Neuroradiology, Lille (France); Law, Meng [NYU Medical Center, Department of Radiology, New York, NY (United States)

    2006-09-15

    Cervical artery dissection is an important cause of ischemic stroke, particularly in young patients. The diagnosis can be made with invasive catheter angiography or non-invasive imaging, either with MRI in conjunction with MR angiography (MRA) or CT angiography (CTA). Both modalities have been shown to have a high specificity and sensitivity. New developments such as multi-slice CTA (MSCTA) are emerging as an alternative methods for imaging the cervical and intracranial arteries. However, the contribution of modern MSCTA to carotid artery dissection has not been reported. We present a retrospective series of seven patients in whom both MSCTA and cervical axial T1 MRI and MRA were performed in the acute to subacute setting of internal carotid artery dissection. Carotid artery dissection was identified in all seven patients by MSCTA. The combination of MRI and MRA identified dissection in five of the seven patients. Additionally, a pseudoaneurysm was identified by MSCTA that was missed by MRI and MRA. Our findings confirm that MSCTA is a complementary technique in comparison to cervical axial T1 MRI and cervical MRA for diagnosing carotid artery dissection, and at times may provide additional information that can impact patient management. (orig.)

  2. 320-Multidetector row whole-head dynamic subtracted CT angiography and whole-brain CT perfusion before and after carotid artery stenting: Technical note

    Energy Technology Data Exchange (ETDEWEB)

    San Millan Ruiz, Diego, E-mail: dsanmil1@jhmi.ed [Division of Interventional Neuroradiology, Department of Radiology, Johns Hopkins Hospital, 600 North Wolfe Street, B-100, Baltimore, MD 21287 (United States); Murphy, Kieran, E-mail: KMURPHY@jhmi.ed [Division of Interventional Neuroradiology, Department of Radiology, The Johns Hopkins Hospital, 600 North Wolfe Street, B-100, Baltimore, MD 21287 (United States); Gailloud, Philippe, E-mail: pgailloud@cerebrovascular.ne [Division of Interventional Neuroradiology, Department of Radiology, Johns Hopkins Hospital, 600 North Wolfe Street, B-100, Baltimore, MD 21287 (United States)

    2010-06-15

    Introduction: Multidetector CT (MDCT) is increasingly used for the investigation of neurovascular disorders, but restricted z-axis coverage (3.2 cm for 64-MDCT) currently limits perfusion to a small portion of the brain close to the circle of Willis, and precludes dynamic angiographic appreciation of the entire brain circulation. We illustrate the clinical potential of recently developed 320-MDCT extending the z-axis coverage to 16 cm in a patient with symptomatic carotid artery stenosis. Methods: In a 74-year-old patient presenting with critical symptomatic stenosis of the left CCA, pre- and post-carotid artery stenting whole-head subtracted dynamic MDCT angiography and perfusion were obtained in addition to CT angiography of the supra-aortic trunks. Both whole-head subtracted MDCT angiography and perfusion demonstrated delayed left ICA circulation, which normalized after carotid stenting. Discussion: 320-MDCT offers unprecedented z-axis coverage allowing for whole-brain perfusion and subtracted dynamic angiography of the entire intracranial circulation. These innovations can consolidate the role of MDCT as a first intention imaging technique for cerebrovascular disorders, in particular for the acute management of stroke.

  3. Rowing injuries.

    Science.gov (United States)

    Rumball, Jane S; Lebrun, Constance M; Di Ciacca, Stephen R; Orlando, Karen

    2005-01-01

    Participation in the sport of rowing has been steadily increasing in recent decades, yet few studies address the specific injuries incurred. This article reviews the most common injuries described in the literature, including musculoskeletal problems in the lower back, ribs, shoulder, wrist and knee. A review of basic rowing physiology and equipment is included, along with a description of the mechanics of the rowing stroke. This information is necessary in order to make an accurate diagnosis and treatment protocol for these injuries, which are mainly chronic in nature. The most frequently injured region is the low back, mainly due to excessive hyperflexion and twisting, and can include specific injuries such as spondylolysis, sacroiliac joint dysfunction and disc herniation. Rib stress fractures account for the most time lost from on-water training and competition. Although theories abound for the mechanism of injury, the exact aetiology of rib stress fractures remains unknown. Other injuries discussed within, which are specific to ribs, include costochondritis, costovertebral joint subluxation and intercostal muscle strains. Shoulder pain is quite common in rowers and can be the result of overuse, poor technique, or tension in the upper body. Injuries concerning the forearm and wrist are also common, and can include exertional compartment syndrome, lateral epicondylitis, deQuervain's and intersection syndrome, and tenosynovitis of the wrist extensors. In the lower body, the major injuries reported include generalised patellofemoral pain due to abnormal patellar tracking, and iliotibial band friction syndrome. Lastly, dermatological issues, such as blisters and abrasions, and miscellaneous issues, such as environmental concerns and the female athlete triad, are also included in this article.Pathophysiology, mechanism of injury, assessment and management strategies are outlined in the text for each injury, with special attention given to ways to correct

  4. Depiction of variants of the portal confluence venous system using multidetector row CT. Analysis of 916 cases

    Energy Technology Data Exchange (ETDEWEB)

    Krumm, P.; Schraml, C.; Bretschneider, C.; Seeger, A.; Klumpp, B.; Kramer, U.; Claussen, C.D.; Miller, S. [Universitaetsklinikum Tuebingen (Germany). Abt. fuer Diagnostische und Interventionelle Radiologie

    2011-12-15

    Purpose: Detailed knowledge of the venous mesenteric system is important for gastrointestinal surgery, particularly for transplantation planning and surgery and for the comprehension of perioperative complications that may influence patient outcome. Data about the mesenteric venous anatomy in the literature varies substantially. The purpose of this study was to categorize venous mesenteric variants and to determine their incidence. Materials and Methods: We included 916 patients requiring diagnostic abdominal CT in the portal venous phase. The mesenteric vein anatomy was categorized as follows: 1. the inferior mesenteric vein (IMV) enters the splenic vein (SV); 2. the IMV enters into the angle of the confluence of the SV and superior mesenteric vein (SMV) forming the portal vein (PV); 3. the IMV enters the SMV; 4. seven rare variants. We measured the diameters of the veins and distances from the confluence to the IMV origins. Results: The frequency of variants was: 1. 37.6 %, 2. 28.8 %; 3. 19.2 %. The rare variants totaled 14.4 %. The average vessel diameters measured in cm: PV 1.48; SV 1.02; SMV 1.2; IMV 0.5. The mean IMV entering distances were 1.66 cm in variant 1 and 0.75 cm in variant 3. Conclusion: The three common variants (1, 2 and 3) are the most relevant ones. 14.4 % of patients had different anatomic variants. The variability of the mesenteric venous system was higher than previously published. Knowledge of rare variants is important to avoid complications in abdominal surgery. (orig.)

  5. Evaluation of middle cerebral artery stents using multidetector row CT angiography in vivo study: comparison of the three different kernels

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Jin Hee; Lim, Yeon Soo; Lee, Youn Joo; Yoo, Won Jong; Sung, Mi Sook (Dept. of Radiology, Bucheon St Mary' s Hospital, Coll. of Medicine, The Catholic Univ. of Korea, Bucheon (Korea, Republic of)), email: wjyu@catholic.ac.kr; Kim, Bum Soo (Dept. of Radiology, Seoul St Mary' s Hospital, Coll. of Medicine, The Catholic Univ. of Korea, Seoul (Korea, Republic of))

    2012-05-15

    Background: There are very few reports assessing middle cerebral artery (MCA) stents using multidetector computed tomography (MDCT). Purpose: To assess MCA stents using multidetector CT angiography (CTA) in vivo evaluation: the differences in the CTA results according to the three different kernels. Material and Methods: We retrospectively evaluated 27 MCA stents from 26 patients who underwent CTA with 16- and 64-slice MDCT after percutaneous transluminal angioplasty and stenting (PTAS). By CTA, using medium-smooth kernel (B30), medium-sharp kernel (B50), and sharp kernel (B60), the lumen diameter, artificial luminal narrowing (ALN), and subjective visibility score of the stented vessels were evaluated. The subjective visibility score ranged from 1 (poor quality) to 5 (excellent) using a five-point scale. Results: There were excellent inter-observer agreements for the lumen diameter measurements (P < 0.001). The mean diameter of the stented vessels was 2.10 +- 0.31 mm on digital subtraction angiography (DSA), 0.93 +- 0.20 mm on CTA using B30, 1.18 +- 0.27 mm on CTA using B50, and 1.29 +- 0.29 mm on CTA using B60. The mean ALN was 55.7 +- 6.0% on CTA using B30, 43.8 +- 7.5% on CTA using B50, and 38.7 +- 8.3% on CTA using B60. CTA with higher kernels had a smaller ALN than images with smaller kernels. The median subjective visibility score on the CTA using B50 was 3, which was higher than for the other kernels. The differences in the lumen diameter, ALN, and the subjective visibility score of the stented vessels on CTA using the three different kernels was statistically significant (P < 0.001). Conclusion: The sharp kernel was better to assess the lumen diameter and ALN, but was inferior to the medium-sharp kernel for in-stent evaluation due to high image-to-noise. CTA with medium-sharp kernel showed good lumen visibility and acceptable ALN for MCA stents. This could therefore be a non-invasive, readily applicable clinical method for assessing MCA stent patency after

  6. Dose reduction and image quality assessment in 64-detector row computed tomography of the coronary arteries using an automatic exposure control system.

    Science.gov (United States)

    Francone, Marco; Di Castro, Elisabetta; Napoli, Alessandro; Bolzan, Chiara; Carbone, Iacopo; Bertoletti, Linda; Iuliano, Luigi; Catalano, Carlo; Passariello, Roberto

    2008-01-01

    To evaluate dose reduction and image quality in coronary 64-slice multidetector computed tomography using an automatic exposure control system (AECs). A total of 101 patients were divided into 4 groups. Tube current was 600 and 800 mAs in groups A and B and adapted at 600 and 800 quality-reference mAs using an AECs in groups C and D. Effective dose and organ-equivalent dose were evaluated. Image noise was quantified as standard deviation of air-space attenuation. Two observers assessed technical adequacy and image quality using a 4-point scale. Effective dose ranged from 8.6 mSv (group C) to 15 mSv (group B) with significant dose reduction for examinations performed at 600 mAs (21.7%) and 800 mAs (29.4%). Contribution of organ-equivalent doses showed higher exposure for lungs (42%) and breast (22%). Noise was significantly higher in groups studied with AECs. Larger coronary segments resulted in higher image quality scores without differences between groups. Automatic exposure control systems provides images of diagnostic quality with substantial dose reduction.

  7. Volume-rendered hemorrhage-responsible arteriogram created by 64 multidetector-row CT during aortography: utility for catheterization in transcatheter arterial embolization for acute arterial bleeding.

    Science.gov (United States)

    Minamiguchi, Hiroki; Kawai, Nobuyuki; Sato, Morio; Ikoma, Akira; Sanda, Hiroki; Nakata, Kouhei; Tanaka, Fumihiro; Nakai, Motoki; Sonomura, Tetsuo; Murotani, Kazuhiro; Hosokawa, Seiki; Nishioku, Tadayoshi

    2014-01-01

    Aortography for detecting hemorrhage is limited when determining the catheter treatment strategy because the artery responsible for hemorrhage commonly overlaps organs and non-responsible arteries. Selective catheterization of untargeted arteries would result in repeated arteriography, large volumes of contrast medium, and extended time. A volume-rendered hemorrhage-responsible arteriogram created with 64 multidetector-row CT (64MDCT) during aortography (MDCTAo) can be used both for hemorrhage mapping and catheter navigation. The MDCTAo depicted hemorrhage in 61 of 71 cases of suspected acute arterial bleeding treated at our institute in the last 3 years. Complete hemostasis by embolization was achieved in all cases. The hemorrhage-responsible arteriogram was used for navigation during catheterization, thus assisting successful embolization. Hemorrhage was not visualized in the remaining 10 patients, of whom 6 had a pseudoaneurysm in a visceral artery; 1 with urinary bladder bleeding and 1 with chest wall hemorrhage had gaze tamponade; and 1 with urinary bladder hemorrhage and 1 with uterine hemorrhage had spastic arteries. Six patients with pseudoaneurysm underwent preventive embolization and the other 4 patients were managed by watchful observation. MDCTAo has the advantage of depicting the arteries responsible for hemoptysis, whether from the bronchial arteries or other systemic arteries, in a single scan. MDCTAo is particularly useful for identifying the source of acute arterial bleeding in the pancreatic arcade area, which is supplied by both the celiac and superior mesenteric arteries. In a case of pelvic hemorrhage, MDCTAo identified the responsible artery from among numerous overlapping visceral arteries that branched from the internal iliac arteries. In conclusion, a hemorrhage-responsible arteriogram created by 64MDCT immediately before catheterization is useful for deciding the catheter treatment strategy for acute arterial bleeding.

  8. Is aortic atherothrombotic disease detected using multidetector-row CT associated with an increased risk of early ischemic lesion recurrence after acute ischemic stroke?

    Science.gov (United States)

    Ko, Youngchai; Kim, Wook-Joo; Jang, Myung Suk; Yang, Mi Hwa; Park, Jung Hyun; Choi, Sang Il; Chun, Eun Ju; Lee, Soo Joo; Han, Moon-Ku; Bae, Hee-Joon

    2012-03-01

    Multidetector-row CT (MDCT) is emerging as a new tool for diagnosing aortic atherothrombotic disease (AAD). We elucidated whether MDCT-detected AAD is associated with an increased risk of early ischemic lesion recurrence on diffusion-weighted MRI after ischemic stroke. A consecutive series of patients with acute ischemic stroke confirmed using diffusion-weighted MRI who were hospitalized within 48 hours after symptom onset and underwent MDCT were identified in a prospective stroke registry database. AAD on MDCT was defined as the presence of plaque formation that was noncalcified and ≥4 mm thick, ulcerative, or soft and thrombosed (vulnerable) in the proximal aortic arch. Ischemic lesion recurrence on diffusion-weighted MRI was defined as the occurrence of any new lesion separate from the index lesion on follow-up diffusion-weighted MRI performed within 14 days after symptom onset. A total of 138 patients was selected. MDCT detected AAD in 24 of 138 (17.4%); ≥4 mm thickness in 17 of 138 (12.3%); ulcerated plaque in 20 of 138 (14.5%); and vulnerable plaque in 16 of 138 (11.6%). With respect to diffusion-weighted MRI lesion recurrence, the crude ORs (95% CIs) were as follows: AAD, 3.56 (1.43-8.89); vulnerable plaque, 3.21 (1.11-9.30); ulcerated plaque, 3.37 (1.27-8.95); and ≥4 mm thickness of the noncalcified plaque, 4.23 (1.11-16.19). These results remained significant after adjustments for potential confounders were made. This study shows that AAD detected by MDCT increases the risk of early ischemic lesion recurrence after acute ischemic stroke, thus supporting the role of MDCT in diagnosing AAD and assessing its contribution to recurrence.

  9. Primary Experiences in 320-Row-640-Slice Dynamic CT for Checking Acute Chest Pain%320排640层动态容积CT 在急性胸痛检查中的初步探讨

    Institute of Scientific and Technical Information of China (English)

    马国军; 于淑靖; 何翔; 郑婧; 魏书恒; 王燕

    2011-01-01

    Objective: To evaluate the image quality and clinic value of dynamic CT checking triple rule-out.Method:38 patients suffering acute chest pain were continuously selected and accepted 320-row-640-slice dynamic CT examination.The scan protocol was helical scanning the whole chest, under ECG-gate,intelligent and automatically trigger.80~90ml contrast media was needed.Two professional doctors measure the CT value of ascending main aorta,decline main aorta and pulmonary artery separately in pulmonary trunk level .The image quality of coronary artery was evaluated,which was graded in three levels:good,well,bad.The dose of radiation was also evaluated .Result: The average CT value of ascending main aorta, decline main aorta and pulmonary artery was (401 ±57)HU,(397±49) HU,(331 ±31)HU.84.7% of all image quality of coronary artery were good,13.2% were well,2.1% were bad.4 patients were diagnosed lung infection with pleurar effusion, 1 patient was lung cancer,2 patients pulmonary embolism,1 patient dissection of aorta,2 patients artrial myxoma.The degree of stenosis was more than 50% in 12 patients' coronary artery.Average radiation dose was (22 ±2.1)mSv. Conclusion:This scanning protocol can achieve high quality image of main aorta,pulmonary artery and coronary artery comparing with the reports of literature.lt is very valuable for finding pathogen of acute chest pain.The dose of contrast media and radiation were lower.%目的:探讨320 排640 层动态容积CT 胸痛三联检查的图像质量及临床价值.方法:连续选取38 例急性胸痛患者行320 排640 层动态容积CT 检查.扫描方案为心电门控下全胸部螺旋扫描(160 mm×0.5mm),采用智能自动触发技术.对比剂用量为80~90ml( 碘海醇350).分别由2位专业医生测定肺动脉干层面的升主动脉、降主动脉、肺动脉干CT 值并评价冠脉质量,冠脉质量分为优、良、差三级.同时评价辐射剂量.结果:升主动脉、降主动脉、肺动脉平均CT

  10. Localization of bleeding using 4-row detector-CT in patients with clinical signs of acute gastrointestinal hemorrhage; Blutungslokalisation mittels 4-Zeilen-Spiral-CT bei Patienten mit klinischen Zeichen einer akuten gastrointestinalen Haemorrhagie

    Energy Technology Data Exchange (ETDEWEB)

    Ko, H.S.; Tesdal, K.; Dominguez, E.; Kaehler, G.; Sadick, M.; Dueber, C.; Diehl, S. [Universitaetsklinikum Heidelberg (Germany). Kinderklinik

    2005-12-15

    Purpose: There is no gold-standard regarding the diagnostic work-up and therapy of an acute gastrointestinal (GI) hemorrhage. In most cases endoscopy provides the diagnosis but in a low percentage this modality is not feasible or negative. Purpose of this study was to evaluate the role of multi-phase Multi-Slice-Computertomography (MSCT) as a modality to diagnose and locate the site of acute GI hemorrhage in case of unfeasible or technically difficult endoscopy. Materials and methods: 58 patients, presenting with clinical signs of lower GI hemorrhage, were examined through a 24-month period. Preliminary endoscopy was either negative or unfeasible. Images were obtained with a four-detector row CT with an arterial (4 x 1 mm collimation, 0.8 mm increment, 1.25 mm slice width, 120 kV, 165 mAs) and portal venous series (4 x 2,5 mm collimation, 2 mm increment, 3 mm slice width, 120 kV, 165 mAs). Time interval between endoscopy and CT varied between 30 minutes and 3 hours. The results of the MSCT were correlated with clinical course and surgical or endoscopical treatment. Results: 20 of the 58 patients (34%) undergoing MSCT had a bleeding site identified, thus providing decisive information for the following intervention. In case of a following therapeutic intervention there was 100% correlation regarding the bleeding site. In 38 of the 58 patients (66%), a bleeding site was not identified by MSCT. Twenty of these 38 patients (53%) were stable and required no further treatment. In 18 of these 38 patients further interventional therapy was required due to continuing hemorrhage and in all of those patients the bleeding site was detected by intervention. (orig.)

  11. Using 80 kVp on a 320-row scanner for hepatic multiphasic CT reduces the contrast dose by 50 % in patients at risk for contrast-induced nephropathy

    Energy Technology Data Exchange (ETDEWEB)

    Taguchi, Narumi; Oda, Seitaro; Utsunomiya, Daisuke; Nakaura, Takeshi; Imuta, Masanori; Yamamura, Sadahiro; Yuki, Hideaki; Kidoh, Masafumi; Hirata, Kenichiro; Namimoto, Tomohiro; Yamashita, Yasuyuki [Kumamoto University, Department of Diagnostic Radiology, Faculty of Life Sciences, Kumamoto (Japan); Funama, Yoshinori [Kumamoto University, Department of Medical Physics, Faculty of Life Sciences, Kumamoto (Japan); Hatemura, Masahiro; Kai, Noriyuki [Kumamoto University Hospital, Department of Central Radiology, Kumamoto (Japan)

    2017-02-15

    We evaluated the effects of a low contrast material (CM) dose protocol using 80-kVp on the image quality of hepatic multiphasic CT scans acquired on a 320-row CT scanner. We scanned 30 patients with renal insufficiency (eGFR < 45 mL/min/1.73 m{sup 2}) using 80-kVp and a CM dose of 300mgI/kg. Another 30 patients without renal insufficiency (eGFR > 60 mL/min/1.73 m{sup 2}) were scanned with the conventional 120-kVp protocol and the standard CM dose of 600mgI/kg. Quantitative image quality parameters, i.e. CT attenuation, image noise, and the contrast-to-noise ratio (CNR) were compared and the visual image quality was scored on a four-point scale. The volume CT dose index (CTDI{sub vol}) and the size-specific dose estimate (SSDE) recorded with the 80- and the 120-kVp protocols were also compared. Image noise and contrast enhancement were equivalent for the two protocols. There was no significant difference in the CNR of all anatomic sites and in the visual scores for overall image quality. The CTDI{sub vol} and SSDE were approximately 25-30 % lower under the 80-kVp protocol. Hepatic multiphase CT using 80-kVp on a 320-row CT scanner allowed for a decrease in the CM dose and a reduction in the radiation dose without image quality degradation in patients with renal insufficiency. (orig.)

  12. Diagnostic value of 320-detector row CT in patients with intracranial internal carotid artery aneurysms%320排动态容积CT诊断颈内动脉颅内段动脉瘤的价值

    Institute of Scientific and Technical Information of China (English)

    陈友三; 陈信坚; 邹佳妮; 罗金香; 胡纯民; 周佩

    2011-01-01

    Objective : To evaluate the diagnostic value of 320-detector row CT in patients with intracranial internal carotid artery aneurysms. Methods : 48 patients were diagnosed with of intracranial internal carotid artery aneurysms by 320-detector row CT angiography. The image of 48 patients were retrospectivcly analyzed combined with patient history and the results of digital subtraction angiography (DSA). Image quality of CT angiography and position of aneurysms, number, and maximal dimension were recorded. Results : Fineness rate of 320-detector CTA image of intracranial internal carotid artery aneurysms was 94%. A rotal of 53 aneurysms were derected by 320-detector row CT angiography in 48 patients. Among them, 31 patients had single aneurysm. 17 patients had several aneurysms, 45 were saccular aneurysm, and 3 were fusiform aneury. In saccular aneurysms, the number of microaneurysm (<5 mm) was 44, and location in posterior communicating artery section was 25. Conclusion: 320-detector row CT angiography can exactly discover and evaluate intracranial internal carotid artery aneurysms, especially have high value in screening intracranial internal carotid artery aneurysms.%目的:评价320排动态容积CT在颈内动脉颅内段动脉瘤诊断中的价值.方法:2010年4月~2010年11月间经320排动态容积CT检出颈内动脉颅内段动脉瘤48例,回顾性分析其临床资料,评价CTA图像质量及动脉瘤特征,并与DSA结果对照.结果:320排动态容积CT脑血管成像动脉瘤显示优良率为94%.48例患者共检出颈内动脉颅内段动脉瘤53个,其中单发31例,多发17例;囊状动脉瘤45例,梭形动脉瘤3例.囊状动脉瘤中,最大径<5mm的小动脉瘤有44个,发生在交通段数目最多,为25个.结论:320排动态容积CT能够准确发现和评价颈内动脉颅内段动脉瘤,特别在颈内动脉颅内段动脉瘤的筛查中具有重要价值.

  13. Application of 16-detector row CT in the diagnosis and preoperative assessment of pulmonary sequestration%16排CT在肺隔离症诊断和术前评估中的价值

    Institute of Scientific and Technical Information of China (English)

    朱石柱

    2011-01-01

    目的 评估16排CT在肺隔离症(PS)诊断和术前评估中的价值.方法 经手术和病理证实的年龄为1个月~39岁的PS患者32例,纳入本研究,其中2005年3月前收治的22例采用X线胸片、超声、MR或血管造影等方法检查;2005年3月后收治的10例患者行16排CT检查生成多平面重建(MPVR)、最大密度投影(MIP)和容量再现图像(VR).软组织和肺窗设置中观察轴像以评估实质改变.结果 应用16排CT检查前,22例PS中漏诊10例(45.5%),误诊7例(31.8%),术中操作发生大出血11例(50.0%);而应用16排CT检查后,10例PS中仅有漏诊1例(10.0%),无误诊病例,术中大出血1例(10.0%),应用16排CT前后比较差异均有统计学意义(P<0.05).结论 16排CT血管成像能准确显示异常动脉血供和静脉回流,在PS的诊断和术前评估中具有极大价值.%Objective To evaluate the role of 16-detector row CT in the diagnosis and preoperative assessment in pulnonary sequestration( PS ).Methods 32 patients with age range from 1 month to 39 years with PS proved with operation and pathology were included in this study.22 of those patients who were collected before March 2005 underwent chest X-ray film, ultrasound, magnetic resonance or angiography.10 of those patients who were collected after March 2005 underwent 16-detector row CT, and MPVR, MIP and 3D volume rendered images were used for diagnosis.The axial images were also reviewed at soft tissue and lung window settings to evaluate the parenchyma changes.Results The number of missed diagnosis for PS patients, misdiagnosed as PS and occurrence of intra-operative bleeding were 10( 45.5% ),7( 31.8% )and 11( 50.0% )cases separately before application of 16-detector row CT.After usage of 16-detector row CT, only 1 case were missed( 10.0% )in these 10 patients, no misdiagnosed cases were found and intra-operative bleeding were ole case( 10.0% ).Data between before and after application of 16-detector row CT were

  14. Retrospectively ECG-gated multi-detector row CT of the chest: does ECG-gating improve three-dimensional visualization of the bronchial tree?

    Energy Technology Data Exchange (ETDEWEB)

    Schertler, T.; Wildermuth, S.; Willmann, J.K.; Crook, D.W.; Marincek, B.; Boehm, T. [Dept. Medical Radiology, Inst. of Diagnostic Radiology, Univ. Hospital Zurich (Switzerland)

    2004-04-01

    Purpose: To determine the impact of retrospectively ECG-gated multi-detector row CT (MDCT) on three-dimensional (3D) visualization of the bronchial tree and virtual bronchoscopy (VB) as compared to non-ECG-gated data acquisition. Materials and Methods: Contrast-enhanced retrospectively ECG-gated and non-ECG-gated MDCT of the chest was performed in 25 consecutive patients referred for assessment of coronary artery bypass grafts and pathology of the ascending aorta. ECG-gated MDCT data were reconstructed in diastole using an absolute reverse delay of -400 msec in all patients. In 10 patients additional reconstructions at -200 msec, -300 msec, and -500 msec prior to the R-wave were performed. Shaded surface display (SSD) and virtual bronchoscopy (VB) for visualization of the bronchial segments was performed with ECG-gated and non-ECG-gated MDCT data. The visualization of the bronchial tree underwent blinded scoring. Effective radiation dose and signal-to-noise ratio (SNR) for both techniques were compared. Results: There was no significant difference in visualizing single bronchial segments using ECG-gated compared to non-ECG-gated MDCT data. However, the total sum of scores for all bronchial segments visualized with non-ECG-gated MDCT was significantly higher compared to ECG-gated MDCT (P<0.05). The summary scores for visualization of bronchial segments for different diastolic reconstructions did not differ significantly. The effective radiation dose and the SNR were significantly higher with the ECG-gated acquisition technique (P<0.05). Conclusion: The bronchial tree is significantly better visualized when using non-ECG-gated MDCT compared to ECG-gated MDCT. Additionally, non-ECG-gated techniques require less radiation exposure. Thus, the current retrospective ECG-gating technique does not provide any additional benefit for 3D visualization of the bronchial tree and VB. (orig.) [German] Ziel: Untersuchung des Einflusses der retrospektiven EKG-Synchronisierung auf

  15. Analysis of 64-row multidetector CT images for preoperative angiographic evaluation of potential living kidney donors; Analyse der mehrphasigen 64-Zeilen-Multidetektor-Computertomographie zur praeoperativen angiographischen Evaluation potenzieller Lebendnierenspender

    Energy Technology Data Exchange (ETDEWEB)

    Blondin, D.; Andersen, K.; Kroepil, P.; Cohnen, M.; Moedder, U.; Jung, G. [Universitaetsklinikum Duesseldorf, Institut fuer Diagnostische Radiologie, Duesseldorf (Germany); Sandmann, W. [Universitaetsklinikum Duesseldorf, Klinik fuer Gefaesschirurgie und Nierentransplantation, Duesseldorf (Germany); Ivens, K. [Universitaetsklinikum Duesseldorf, Klinik fuer Nephrologie, Duesseldorf (Germany)

    2008-07-15

    Anatomical imaging and the ascertainment of any anomalies in the renal vessels and the ureters are essential in the planning of a kidney donation. The aim of the present study was to assess the value of 64-row multidetector CT in noninvasive examination of the renal vessels and ureters of potential living kidney donors. The evaluation embraced 63 living renal donors (LNS) who underwent preoperative CT examination from December 2004 to January 2007. The examinations were all carried out using a Somatom Sensation -Cardiac 64 (Siemens Medical Solutions, Germany). As well as CT angiography (CTA), a venous phase of the abdomen and a late phase after 15 min using low-dose technique were performed for CT urography (CTU). The radiological findings were compared with the surgical results, or with the angiograms in 2 cases. Sensitivity, specificity and both negative and positive predictive value were calculated. In the 63 (31 female, 32 male) donors CTA had a sensitivity of 100% in examination of the main and accessory renal arteries and of 98.3% when the venous and ureteric anatomy were assessed. The sensitivity of low-dose CTU was also 100%. The findings recorded in this study indicate that noninvasive preoperative planning with 64-row multidetector CTA and CTU is a reliable 'one-stop shopping' method of examination for potential living kidney donors. (orig.) [German] Die anatomische Darstellung und Erfassung moeglicher Anomalien der Nierengefaesse und Ureteren ist fuer die Planung einer Lebendnierenspende von essenzieller Bedeutung. Die vorliegende Untersuchung soll die Wertigkeit der nichtinvasiven Evaluation mit der 64-Zeilen-Multidetektor-CT untersuchen. In die Auswertung wurden 63 Lebendnierenspender (LNS) eingeschlossen, die im Zeitraum 12.2004 bis 01.2007 mit der CT praeoperativ untersucht wurden. Die Untersuchungen erfolgten mit einem Somatom-Sensation-Cardiac-64 (Siemens Medical Solutions, Deutschland). Neben einer CT-Angiographie (CTA) wurden eine

  16. The Value of Multi-detector row CT in Gastroenteropathy and Application of Contrast Agents%MDCT在胃肠道检查中的价值及对比剂的应用

    Institute of Scientific and Technical Information of China (English)

    鲁桂青; 陈克敏; 刘林祥

    2007-01-01

    胃肠道疾患在过去以传统的检查方法 (主要为消化道钡剂透视及纤维内窥镜)为主,随着多层螺旋CT(multi-detector row CT,MDCT)的快速发展以及各种不同腔内对比剂的研究与应用,CT对胃肠道的检查价值显著提高。

  17. Acute pulmonary embolism: prediction of cor pulmonale and short-term patient survival from assessment of cardiac dimensions in routine multidetector-row CT; Mehrschicht-Spiral-CT bei vermuteter und inzidenteller akuter Lungenembolie: prognostischer Wert morpholoqischer Herzparameter

    Energy Technology Data Exchange (ETDEWEB)

    Engeike, C. [Radiologie, Klinikum rechts der Isar der Technischen Univ. Muenchen (Germany); Rummeny, E.; Marten, K. [Inst. fuer Roentgendiagnostik, Klinikum rechts der Isar der Technischen Univ. Muenchen (Germany)

    2006-10-15

    Purpose: evaluation of the prognostic value of morphological cardiac parameters in patients with suspected and incidental acute pulmonary embolism (PE) using multidetector-row chest CT (MSCT). Materials and methods: 2335 consecutive MSCT scans were evaluated for the presence of PE. The arterial enhancement and analysability of pulmonary arteries and the heart were assessed as parameters of the scan quality. The diastolic right and left ventricular short axes (RV{sub D}, LV{sub D}) and the interventricular septal deviation (ISD) were measured in all PE-positive patients and the echocardiography reports were reviewed. The clinical data assessment included cardio-respiratory and other co-morbidities, systemic anticoagulant therapy (ACT), and the 30-day outcome. Predictors of acute cor pulmonale and the short-term outcome were calculated by univariate and multivariate logistic regressions including odds ratios (OR) and ROC analyses using positive (PPV) and negative predictive values (NPV). Results: 90 patients with acute PE were included (36 with clinically suspected PE, 54 with incidental PE). 26 patients had cardio-respiratory co-morbidities. Four patients underwent systemic thrombolysis, 43 underwent anticoagulation in therapeutic doses, 19 underwent anticoagulation in prophylactic doses, and 24 patients did not undergo ACT. 15 of 41 patients had echocardiographic evidence of acute cor pulmonale. 8 patients died within 30 days. The RV{sub D} was the best independent predictor of acute cor pulmonale (p = 0,002, OR = 9.16, PPV = 0.68, NPV=1 at 4.49 cm cut off) and short-term outcome (p= 0,0005, OR = 2.82, PPV = 0.23, NPV = 0.98 at 4.75 cm cut off). The RV{sub D}/LV{sub D} ratio had a PPV of 0.85 for cor pulmonale. (orig.)

  18. Comparison of dynamic contrast-enhanced 3T MR and 64-row multidetector CT angiography for the localization of spinal dural arteriovenous fistulas.

    Science.gov (United States)

    Oda, S; Utsunomiya, D; Hirai, T; Kai, Y; Ohmori, Y; Shigematsu, Y; Iryo, Y; Uetani, H; Azuma, M; Yamashita, Y

    2014-02-01

    For the localization of spinal dural arteriovenous fistulas, it is not determined whether dynamic contrast-enhanced MRA is more reliable than multidetector CTA. The aim of this study was to compare the agreement between intra-arterial DSA, dynamic contrast-enhanced MRA at 3T, and 64-row multidetector CTA for the localization of spinal dural arteriovenous fistulas. We enrolled 12 consecutive patients (11 men, 1 woman; age range, 46-83 years; mean, 65 years) who underwent preoperative dynamic contrast-enhanced MRA at 3T and 64-row multidetector CTA. The spinal dural arteriovenous fistula location was confirmed by intra-arterial DSA as the reference standard. Two reviewers independently evaluated the level of the artery feeding the spinal dural arteriovenous fistula on the basis of continuity between the feeder and abnormal spinal vessels on 3T dynamic contrast-enhanced MRA and 64-row multidetector CTA images. Interobserver and intermodality agreement was determined by calculation of the κ coefficient. On DSA, the vessel feeding the spinal dural arteriovenous fistula was the intercostal artery (7 cases), the lumbar artery (3 cases), and the internal iliac artery or the ascending pharyngeal artery (1 case each). For the fistula level, interobserver agreement was excellent for 3T dynamic contrast-enhanced MRA (κ = 0.97; 95% CI, 0.92-1.00) and very good for 64-row multidetector CTA (κ = 0.84; 95% CI, 0.72-0.96). Intermodality agreement with DSA was good for 3T dynamic contrast-enhanced MRA (κ = 0.78; 95% CI, 0.49-1.00) and moderate for 64-row multidetector CTA (κ = 0.41; 95% CI, 0.020-0.84). For the localization of spinal dural arteriovenous fistulas, 3T dynamic contrast-enhanced MRA may be more reliable than 64-row multidetector CTA.

  19. Dynamic multidetector CT and non-contrast-enhanced MR for right adrenal vein imaging: comparison with catheter venography in adrenal venous sampling.

    Science.gov (United States)

    Ota, Hideki; Seiji, Kazumasa; Kawabata, Masahiro; Satani, Nozomi; Omata, Kei; Ono, Yoshikiyo; Iwakura, Yoshitsugu; Morimoto, Ryo; Matsuura, Tomonori; Kudo, Masataka; Tominaga, Junya; Satoh, Fumitoshi; Ito, Sadayoshi; Takase, Kei

    2016-03-01

    To evaluate visualization of the right adrenal vein (RAV) with multidetector CT and non-contrast-enhanced MR imaging in patients with primary aldosteronism. A total of 125 patients (67 men) scheduled for adrenal venous sampling (AVS) were included. Dynamic 64-detector-row CT and balanced steady-state free precession-based non-contrast-enhanced 3-T MR imaging were performed. RAV visualization based on a four-point score was documented. Both anatomical location and variation on cross-sectional imaging were evaluated, and the findings were compared with catheter venography as the gold standard. The RAV was visualized in 93.2% by CT and 84.8% by MR imaging (p = 0.02). Positive predictive values of RAV visualization were 100% for CT and 95.2% for MR imaging. Imaging score was significantly higher in CT than MR imaging (p 70% of subjects. Success rate of AVS was 99.2%. Dynamic CT is a reliable way to map the RAV prior to AVS. Non-contrast-enhanced MR imaging is an alternative when there is a risk of complication from contrast media or radiation exposure. Dynamic CT and non-contrast-enhanced MR imaging detect the right adrenal vein (RAV). Dynamic CT can visualize the RAV more than non-contrast-enhanced MR imaging. Mapping the RAV helps to achieve successful adrenal venous sampling. Sixteen per cent of RAVs share the common trunk with accessory hepatic veins.

  20. 经胃镜胃黏膜下注射64排螺旋CT胃周淋巴结造影初探%Lymphatic Drainage from Gastric Tract:Preliminary Investigating Feasibility of Endoscopic 64-row Spiral CT Lymphography

    Institute of Scientific and Technical Information of China (English)

    朱建兵; 陈光强; 李勇; 朱江涛; 张伟; 龚建平

    2012-01-01

    目的 初步探讨胃黏膜下注射64排螺旋CT胃周淋巴结造影的应用价值.方法 征集21例志愿患者,进行胃镜下胃黏膜下造影剂注射,然后进行64排螺旋CT扫描.结果 16例患者均在完成64排螺旋CT的扫描获得相应图像.CT图像显示5例患者可见肝脏及血管旁线性致密影呈现;14例非胃癌患者仅8例发现可辨别的淋巴结影,其中2例患者发现胃周淋巴结密度增高.结论 胃镜辅助下64排螺旋CT胃周淋巴结造影作为一种潜在的术前淋巴结造影的选择具有一定优越性,但是应用于临床需要进一步的研究.%Objective To investigate feasibility of endoscopic 64-row spiral CT lymphography of the gastric tract preliminarily.Methods With institutional committee approval,a total of 2mL of undiluted iopamidol was injected into the gastric submucosa by endoscope in 21 volunteer patients,then scanning with 64-row spiral CT. Result 16 patients completed CT scan and got the imaging needed;5 patients were found the line high attenuation nearby liver and vascular;8 of the 14 patients were found lymphatic nodes identified;2 patients were found high attenuation lymphatic nodes nearby stomach.Conclusion Endoscopic 64-row spiral CT lymphography of stomach as a potentially lymphography of the stomach,still needs more investigation for clinic application.

  1. High-concentration contrast media in neurological multidetector-row CT applications: implications for improved patient management in neurology and neurosurgery

    Energy Technology Data Exchange (ETDEWEB)

    Schramm, Peter [University of Heidelberg Medical Center, Department of Neuroradiology, Heidelberg (Germany)

    2007-07-15

    Dynamic CT scanning after intravenous injection of iodine contrast medium (CM) was proposed in the very early days of CT. The goal was to characterize tissue by extracting information from the temporal course of enhancement. In the early 1980s, modeling algorithms were already described in the literature for the quantitative calculation of cerebral blood flow (CBF). However, cerebral applications suffered from the insufficient temporal resolution available at that time and the central nervous system was already seen primarily as an MRI domain. The renaissance of dynamic CT in neurological applications came in the middle of the 1990s with the introduction of thrombolytic therapy in acute stroke. With CT being the primary imaging modality, getting additional hemodynamic information from the same device without having to move the patient appeared attractive. Multimodal CT protocols allow a comprehensive diagnosis of the emergency stroke patient in less than 15 minutes by combining nonenhanced CT (NECT), perfusion CT (PCT) and CT angiography (CTA). Dynamic PCT can also render important information in patients with intraaxial brain tumors, allowing differentiation not only between lymphoma and glioma but also between low-grade and high-grade glioma by quantifying local cerebral blood volume (CBV) and permeability of the blood-brain barrier (BBB). Hoever, even if a shorter imaging time permits a reduction in volume of CM, adequate total iodine levels must be preserved for dynamic CT applications. Increased concentrations of iodine are therefore helpful to obtain adequate total iodine levels for imaging. (orig.)

  2. Sensitivity and accuracy of volumetry of pulmonary nodules on low-dose 16- and 64-row multi-detector CT : an anthropomorphic phantom study

    NARCIS (Netherlands)

    Xie, X.; Zhao, Yingru; Snijder, R.A.; van Ooijen, P.M.; de Jong, P.A.; Oudkerk, M.; de Bock, G.H.; Vliegenthart, R.; Greuter, M.J.

    2013-01-01

    To assess the sensitivity of detection and accuracy of volumetry by manual and semi-automated quantification of artificial pulmonary nodules in an anthropomorphic thoracic phantom on low-dose CT. Fifteen artificial spherical nodules (diameter 3, 5, 8, 10 and 12 mm; CT densities -800, -630 and +100 H

  3. 320排640层CT在耳部畸形诊断中的临床应用价值探讨%Diagnosis of ear malformation by 320-detector row 640-slice CT scanner

    Institute of Scientific and Technical Information of China (English)

    郝晓东; 任方远; 牛娟琴; 罗樱; 强海霞; 高崎炜; 张雅滨; 成满平; 韩月东

    2012-01-01

    Objective;To evaluate the diagnostic value of 320 - detector row 640 - slice dynamic volume CT for ear malformation. Methods: Forty -four ears in 31 patients with congenital ear lesions were examined with Toshiba Aquilion One 320 - detector row 640 - slice dynamic volume CT system (160 ×0. 5 volume scanning mode) from January 2011 to January 2012. The conventional 1.0— mm cross - section reconstruction was performed with high — resolution algorithm (sharp verysharp or bone) based on the collected data. Results:In 16 patients, external auditory canal atresia was found in 18 ears, tympanic cavity paramorphia in 4 ears, auditory ossicle paramorphia in 3 ears,both tympanic cavity and auditory ossicle paramorphia in 1 ear,and diploetic type mastoid in 2 patients. Five ears had external auditory canal stenosis in 4 patients. Ninteen ears had paramorphia or malformation of inner ear in 10 patients. Conclusion;The 320 -detector row 640 -slice dynamic volume CT scanner is an advanced and reliable diagnostic tool for ear malformation.%目的:探讨320排640层动态容积CT在耳部畸形诊断上的临床应用价值.方法:收集2011-01~2012-01间行320排640层动态容积CT耳部检查先天性耳部病变患者31例共44耳,使用Toshiba Aquilion One动态容积CT机,采用160×0.5容积扫描模式.采集到的数据,常规进行1.0 mm横断面重建,高分辨率算法(sharp verysharp或bone).结果:外耳道闭锁16例18耳,同时16例中伴有鼓室形态异常4耳,听小骨形态异常3耳,鼓室并听小骨形态异常1耳,患耳侧乳突呈板障型者2耳.外耳道狭窄4例5耳.内耳形态异常或畸形10例19耳.结论:320排640层动态容积CT先进的软硬件技术,评价内耳畸形可靠性进一步提升.

  4. Use of multidetector-row CT colonography for detection of colorectal neoplasia in patients referred via the Department of Health '2-week-wait' initiative

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, S.A.; Halligan, S. E-mail: s.halligan@ic.ac.uk; Saunders, B.P.; Morley, S.; Riesewyk, C.; Atkin, W.; Bartram, C.I

    2003-11-01

    AIM: Patients referred under the Department of Health 2-week wait initiative with symptoms of colorectal cancer frequently undergo whole-colon examination. We investigated the use of computed tomography (CT) colonography as an alternative to colonoscopy in this scenario. MATERIALS AND METHODS: Fifty-four consecutive patients, referred via the 2-week wait initiative and scheduled for colonoscopy, consented to undergo multidetector CT colonography immediately before endoscopy. The site and morphology of any polyp or cancer detected by CT was noted and comparison made with subsequent colonoscopy. RESULTS: Colonoscopy detected polyps or cancer in 29 patients (53.7%). CT colonography prospectively detected 18 of 41 (44%) polyps of 1-5 mm, three of four (75%) polyps of 6-9 mm, four of four (100%) polyps 10 mm or larger, and five of six (83%) cancers. The missed cancer occurred early in the series and was a perceptive error. The overall sensitivity, specificity, positive predictive value and negative predictive value of CT colonography for cancer and polyps 10 mm or greater on a per patient basis were 90, 100, 100 and 98%, respectively. CT detected one renal cancer and one colonic cancer, initially missed due to incomplete colonoscopy. CONCLUSION: CT colonography is a robust technique for investigation of symptomatic patients. The learning curve must be overcome for optimal performance.

  5. 颅内动脉瘤320排CTA与DSA对照分析%Intracranial aneurysms:comparative analysis of 320-detector row CT angiography and digital subtraction angiography

    Institute of Scientific and Technical Information of China (English)

    汪培英; 陈霞; 王波; 李兴; 刘健; 出良钊

    2012-01-01

    目的 探讨320排CTA对颅内动脉瘤诊断的临床应用价值.方法 收集2010-04-2011-03期间行320排CTA和DSA检查的颅内动脉瘤患者33例.将CTA图像质量按颅底骨质残留及血管显示情况分为4个等级,再以DSA所见为对照,分析320排CTA诊断颅内动脉瘤的敏感性及粗符合率.结果 33例经320排CTA检出颅内动脉瘤30例33个、动静脉畸形(AVM)2例、颅内动脉瘤合并AVM 1例;经DSA证实有颅内动脉瘤30例33个、AVM 3例,其中动脉瘤"假阳性"1例;有22例行手术治疗.320排CTA诊断颅内动脉瘤敏感性为100%,粗符合率为97.0%.结论 与DSA比较,320排CTA诊断颅内动脉瘤有较高的敏感性及粗符合率,在术前筛查方面具有广泛的临床应用前景.%Objective To study the effectiveness of 320-detector row CT angiography(CTA) for intracranial aneurysms. Methods 33 cases of intracranial aneurysms were examined during April 2010 to March 2011 by using 320-detector row CTA and DSA. CTA images were ranked by four grades according to skull remaining and artery displaying. The sensitivity and crude accuracy ol 320-detector row CTA in diagnosis of intracranial aneurysms were analysed,and compared with the results of DSA. Results 33 intracranial aneurysms(30 cases) ,2 arteriovenous malformations (2 cases) and 1 intracranial aneurysm accompanied with arteriovenous malformation(1 case) were found by CTA. 33 intracranial aneurysms(30 cases) and 3 arteriovenous malformations(3 cases) were detected by DSA,among aneurysms,one was false positive;22 cases underwent surgical treatment. The sensitivity and accurate rate of CTA in diagnosis of intracranial aneurysms were 100% and 97. 0% ,respectively. Conclusion In comparison with DSA,320-detector row CTA has higher sensitivity and crude accuracy in diagnosis of intracranial aneurysms,it is of significant applied value in pre-operative screening for intracranial aneurysms.

  6. Dynamic multidetector CT and non-contrast-enhanced MR for right adrenal vein imaging: comparison with catheter venography in adrenal venous sampling

    Energy Technology Data Exchange (ETDEWEB)

    Ota, Hideki; Seiji, Kazumasa; Kawabata, Masahiro; Satani, Nozomi; Matsuura, Tomonori; Tominaga, Junya; Takase, Kei [Tohoku University Hospital, Department of Diagnostic Radiology, Sendai (Japan); Omata, Kei; Ono, Yoshikiyo; Iwakura, Yoshitsugu; Morimoto, Ryo; Kudo, Masataka; Satoh, Fumitoshi; Ito, Sadayoshi [Tohoku University Hospital, Division of Nephrology, Endocrinology and Vascular Medicine, Sendai (Japan)

    2016-03-15

    To evaluate visualization of the right adrenal vein (RAV) with multidetector CT and non-contrast-enhanced MR imaging in patients with primary aldosteronism. A total of 125 patients (67 men) scheduled for adrenal venous sampling (AVS) were included. Dynamic 64-detector-row CT and balanced steady-state free precession-based non-contrast-enhanced 3-T MR imaging were performed. RAV visualization based on a four-point score was documented. Both anatomical location and variation on cross-sectional imaging were evaluated, and the findings were compared with catheter venography as the gold standard. The RAV was visualized in 93.2 % by CT and 84.8 % by MR imaging (p = 0.02). Positive predictive values of RAV visualization were 100 % for CT and 95.2 % for MR imaging. Imaging score was significantly higher in CT than MR imaging (p < 0.01). The RAV formed a common trunk with an accessory hepatic vein in 16 % of patients. The RAV orifice level on cross-sectional imaging was concordant with catheter venography within the range of 1/3 vertebral height in >70 % of subjects. Success rate of AVS was 99.2 %. Dynamic CT is a reliable way to map the RAV prior to AVS. Non-contrast-enhanced MR imaging is an alternative when there is a risk of complication from contrast media or radiation exposure. (orig.)

  7. Row fault detection system

    Science.gov (United States)

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D.; Smith, Brian Edward

    2008-10-14

    An apparatus, program product and method checks for nodal faults in a row of nodes by causing each node in the row to concurrently communicate with its adjacent neighbor nodes in the row. The communications are analyzed to determine a presence of a faulty node or connection.

  8. Assessment of coronary artery aneurysms in paediatric patients with Kawasaki disease by multidetector row CT angiography: feasibility and comparison with 2D echocardiography

    Energy Technology Data Exchange (ETDEWEB)

    Chu, W.C.W.; Lam, W.W.M. [Department of Diagnostic Radiology and Organ Imaging, Chinese Univ. of Hong Kong, Shatin (China); Mok, G.C.F.; Yam, M.; Sung, R.Y.T. [Dept. of Pediatrics, Chinese Univ. of Hong Kong, Shatin (China)

    2006-11-15

    Transthoracic ECHO is the locally accepted method for coronary surveillance of patients with Kawasaki disease but it may have limited visualization in the older child. To assess the feasibility of multidetector CT (MDCT) angiography in the follow-up of coronary artery aneurysms in children with previous Kawasaki disease. Six children (5 boys, 1 girl; mean age 11.5 years) with known Kawasaki disease and coronary artery involvement underwent CT coronary angiography using 16-detector MDCT. The visualized lengths and diameter of all coronary segments were measured. The number, size and location of coronary artery aneurysms were recorded and compared with recent ECHO. Twelve coronary artery aneurysms (seven saccular, five fusiform) were identified by MDCT angiography. One saccular aneurysm at the junction of the distal right coronary artery and posterior descending artery was not detected by ECHO while the remaining six in proximal segments were detected by both modalities. Two of five fusiform aneurysms were not detected by ECHO due to their small sizes. Excellent agreement was found between CT and ECHO for maximal diameter and length of the visualized aneurysms. MDCT angiography accurately defines coronary artery aneurysms. It is more sensitive for detecting aneurysms at distal coronary segments and fusiform aneurysms of small size.

  9. Diagnosis and Treatment Value of 64 Row CT in Children With Secretory Otitis Media%64排CT在儿童分泌性中耳炎诊疗中的作用

    Institute of Scientific and Technical Information of China (English)

    付高尚; 徐艳霞; 韩富根

    2015-01-01

    目的:探讨64排CT在儿童分泌性中耳炎诊断、治疗过程中的意义。方法对2012年8月~2014年8月在本院治疗的76例(131耳)分泌性中耳炎患儿的临床资料进行回顾性分析。结果76例(131耳)分泌性中耳炎患儿当中,其中部分患儿3月后复查CT乳突密度影降低,避免了不必要的手术。结论64排颞骨CT检查对儿童分泌性中耳炎病情严重程度准确诊断提供重要的参考价值。%Objective To investigate the 64 slice CT in the diagnosis of children with secretory otitis media,in the course of treatment significance.Methods From August 2012 to August 2014 in our hospital(76 cases(131 ears)of secretory otitis media in children with clinical data were retrospectively analyzed.Results 76 cases(131 ears)with secretory otitis media in children,including review of CT significantly decreased the mastoid density in march part of the children,to avoid unnecessary operation.Conclusion The diagnostic accuracy of 64 row CT scanning of temporal bone of children with secretory otitis media disease severity and provides an important reference value.

  10. Diagnostic accuracy of 16-slice multidetector-row CT for detection of in-stent restenosis vs detection of stenosis in nonstented coronary arteries.

    Science.gov (United States)

    Kefer, Joelle M; Coche, Emmanuel; Vanoverschelde, Jean-Louis J; Gerber, Bernhard L

    2007-01-01

    The purpose of this study was to assess the diagnostic accuracy of 16-slice multidetector-row computed tomography (MDCT) for detecting in-stent restenosis. Fifty patients with 69 previously implanted coronary stents underwent 16-slice MDCT before quantitative coronary angiography (QCA). Diagnostic accuracy of MDCT for detection of in-stent restenosis defined as >50% lumen diameter stenosis (DS) in stented and nonstented coronary segments >1.5-mm diameter was computed using QCA as reference. According to QCA, 18/69 (25%) stented segments had restenosis. In addition, 33/518 (6.4%) nonstented segments had >50% DS. In-stent restenosis was correctly identified on MDCT images in 12/18 stents, and absence of restenosis was correctly identified in 50/51 stents. Stenosis in native coronary arteries was correctly identified in 22/33 segments and correctly excluded in 482/485 segments. Thus, sensitivity (67% vs 67% p=1.0), specificity (98% vs 99%, p=0.96) and overall diagnostic accuracy (90% vs 97%, p=0.68) was similarly high for detecting in-stent restenosis as for detecting stenosis in nonstented coronary segments. MDCT has similarly high diagnostic accuracy for detecting in-stent restenosis as for detecting coronary artery disease in nonstented segments. This suggests that MDCT could be clinically useful for identification of restenosis in patients after coronary stenting.

  11. Diagnostic accuracy of 16-slice multidetector-row CT for detection of in-stent restenosis vs detection of stenosis in nonstented coronary arteries

    Energy Technology Data Exchange (ETDEWEB)

    Kefer, Joelle M.; Vanoverschelde, Jean-Louis J.; Gerber, Bernhard L. [Cliniques Universitaires St. Luc UCL, Department of Cardiology, Brussels (Belgium); Coche, Emmanuel [Cliniques Universitaires St. Luc UCL, Department of Radiology, Brussels (Belgium)

    2007-01-15

    The purpose of this study was to assess the diagnostic accuracy of 16-slice multidetector-row computed tomography (MDCT) for detecting in-stent restenosis. Fifty patients with 69 previously implanted coronary stents underwent 16-slice MDCT before quantitative coronary angiography (QCA). Diagnostic accuracy of MDCT for detection of in-stent restenosis defined as >50% lumen diameter stenosis (DS) in stented and nonstented coronary segments >1.5-mm diameter was computed using QCA as reference. According to QCA, 18/69 (25%) stented segments had restenosis. In addition, 33/518 (6.4%) nonstented segments had >50% DS. In-stent restenosis was correctly identified on MDCT images in 12/18 stents, and absence of restenosis was correctly identified in 50/51 stents. Stenosis in native coronary arteries was correctly identified in 22/33 segments and correctly excluded in 482/485 segments. Thus, sensitivity (67% vs 67% p=1.0), specificity (98% vs 99%, p=0.96) and overall diagnostic accuracy (90% vs 97%, p=0.68) was similarly high for detecting in-stent restenosis as for detecting stenosis in nonstented coronary segments. MDCT has similarly high diagnostic accuracy for detecting in-stent restenosis as for detecting coronary artery disease in nonstented segments. This suggests that MDCT could be clinically useful for identification of restenosis in patients after coronary stenting. (orig.)

  12. Usefulness of multidetector-row CT (MDCT) for the diagnosis of non-occlusive mesenteric ischemia (NOMI): Assessment of morphology and diameter of the superior mesenteric artery (SMA) on multi-planar reconstructed (MPR) images

    Energy Technology Data Exchange (ETDEWEB)

    Woodhams, Reiko, E-mail: reikow@hotmail.co.j [Department of Radiology, Kitasato University School of Medicine, 1-15-1, Kitasato, Sagamihara, Kanagawa 228-8555 (Japan); Nishimaki, Hiroshi, E-mail: emgrad@yhb.att.ne.j [Department of Radiology, Kitasato University School of Medicine, 1-15-1, Kitasato, Sagamihara, Kanagawa 228-8555 (Japan); Emergency Medicine, Kitasato University School of Medicine, 1-15-1, Kitasato, Sagamihara, Kanagawa, 228-8555 (Japan); Fujii, Kaoru, E-mail: kaorufujii@yahoo.co.j [Department of Radiology, Kitasato University School of Medicine, 1-15-1, Kitasato, Sagamihara, Kanagawa 228-8555 (Japan); Kakita, Satoko, E-mail: skakita@kitasato-u.ac.j [Department of Radiology, Kitasato University School of Medicine, 1-15-1, Kitasato, Sagamihara, Kanagawa 228-8555 (Japan); Hayakawa, Kazushige, E-mail: hayakazu@med.kitasato-u.ac.j [Department of Radiology, Kitasato University School of Medicine, 1-15-1, Kitasato, Sagamihara, Kanagawa 228-8555 (Japan)

    2010-10-15

    Objective: The purpose of this study was to assess the efficacy of multidetector-row CT (MDCT) for the diagnosis of non-occlusive mesenteric ischemia (NOMI) by analyzing morphology and diameter of superior mesenteric artery (SMA). We assessed whether MDCT was as useful as angiography for the diagnosis of NOMI. Materials and methods: Four patients who were diagnosed with NOMI were retrospectively analyzed. All patients had 8-row MDCT followed by laparotomy. Two of them underwent angiography after MDCT. The morphology and diameter of SMA of these cases was analyzed on multi-planar reconstructed (MPR) images. The mean diameter of SMA of NOMI cases was compared to that of 13 control cases. Results: MPR images of all NOMI cases showed irregular narrowing of the SMA, spasm of the arcades of SMA, and poor demonstration of intramural vessels. MPR images of two patients who had angiography were concordant with their angiograms. The mean diameter of SMA of NOMI patients was 3.4 {+-} 1.1 mm, which was statistically smaller than that of 13 control patients, 6.0 {+-} 1.5 mm (P < 0.05, Wilcoxon rank sum tests). Conclusion: Angiography has been recognized essential for the diagnosis of NOMI. This study shows the possibility of MDCT to be an equivalently useful modality compared to angiography for the diagnosis of NOMI by interpreting morphologic appearance and diameter of SMA. Introduction of MDCT in the decision tree of NOMI treatment may bring the benefit of prompt diagnosis and subsequent early and efficient initiation of therapy, which may improve the mortality.

  13. Characterization of Dose in a TC of 64-Detectors used in pediatrics. Evaluation of the effects of the Over beaming and Over ranging; Caracterizacion de dosis en un TC de 64 detectores utilizado en pediatria. Evaluacion de los efectos del Overbeaming y Overranging

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Castanon, P.; Roch Gonzalez, M.; Rodriguez Martin, G.; Espana Lopez, M. L.; Giner Sala, M.

    2013-07-01

    The objective of this study is to evaluate the contribution of effects over beaming and over ranging dose received by the patient in a TC multislice with 64 detectors, installed at a children's hospital, for the different acquisition modes available, in order to assess the adequacy of the protocols pre-set for Pediatrics and more accurately assess the received dose. (Author)

  14. Quantification of coronary flow using dynamic angiography with 320-detector row CT and motion coherence image processing: Detection of ischemia for intermediate coronary stenosis.

    Science.gov (United States)

    Nagao, Michinobu; Yamasaki, Yuzo; Kamitani, Takeshi; Kawanami, Satoshi; Sagiyama, Koji; Yamanouchi, Torahiko; Shimomiya, Yamato; Matoba, Tetsuya; Mukai, Yasushi; Odashiro, Keita; Baba, Shingo; Maruoka, Yasuhiro; Kitamura, Yoshiyuki; Nishie, Akihiro; Honda, Hiroshi

    2016-05-01

    Anatomical coronary stenosis is not always indicative of functional stenosis, particularly for intermediate coronary lesions. The purpose of this study is to propose a new method for quantifying coronary flow using dynamic CT angiography for the whole heart (heart-DCT) and investigate its ability for detecting ischemia from intermediate coronary stenosis. Participants comprised 36 patients with coronary artery disease who underwent heart-DCT using 320-detector CT with tube voltage of 80kV and myocardial perfusion scintigraphy (MPS). Heart-DCT was continuously performed at mid-diastole throughout 15-25 cardiac cycles with prospective ECG-gating after bolus injection of contrast media (12-24ml). Dynamic datasets were computed into 90-100 data sets by motion coherence image processing (MCIP). Next, time-density curves (TDCs) for coronary arteries with a diameter >3mm were automatically calculated for all phases using MCIP. On the basis of the maximum slope method, coronary flow index (CFI) was defined as the ratio of the maximum upslope of coronary artery attenuation to the upslope of ascending aorta attenuation on the TDC, and was used to quantify coronary flow. CFIs for the proximal and distal sites of coronary arteries with mild-to-moderate stenosis were calculated. Coronary territories were categorized as non-ischemic or ischemic by MPS. Receiver-operating-characteristic (ROC) analysis was performed to determine the optimal cutoff for CFI to detect ischemia. Distal CFI was significantly lower for ischemia (0.26±0.08) than for non-ischemia (0.50±0.17, pcoronary flow quantification using heart-DCT. Distal CFI can detect myocardial ischemia derived from intermediate coronary stenosis. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  15. Estudio del oído con TC Multidetector de 64 canales 64 - Detector CT findings in the study of the ear

    OpenAIRE

    2010-01-01

    El oído es una estructura anatómica compleja. Su estudio y comprensión resultan un reto diario para el radiólogo, siendo la tomografía computada una herramienta esencial para su estudio. La tomografía computada convencional con cortes finos en planos axiales y coronales permite una buena visualización de las diferentes estructuras. Sin embargo, se necesitan tiempos prolongados para su realización y posicionamientos incómodos o intolerables para muchos pacientes. Además la visualización de alg...

  16. Estudio del oído con TC Multidetector de 64 canales 64 - Detector CT findings in the study of the ear

    Directory of Open Access Journals (Sweden)

    María Lourdes Mallo

    2010-12-01

    Full Text Available El oído es una estructura anatómica compleja. Su estudio y comprensión resultan un reto diario para el radiólogo, siendo la tomografía computada una herramienta esencial para su estudio. La tomografía computada convencional con cortes finos en planos axiales y coronales permite una buena visualización de las diferentes estructuras. Sin embargo, se necesitan tiempos prolongados para su realización y posicionamientos incómodos o intolerables para muchos pacientes. Además la visualización de algunas de sus estructuras es limitada. La tomografía axial computada multidetector de 64 canales a nuestro medio permite optimizar el estudio de la compleja y pequeña anatomía del oído. La realización de adquisiciones volumétricas con cortes de 0,5 mm, con reconstrucciones multiplanares en los tres planos básicos, en planos curvos y reconstrucciones tridimensionales, hacen posible la visualización detallada de las estructuras en escasos segundos y en condiciones cómodas para el paciente. Nuestro propósito en este artículo es demostrar la utilidad de las reconstrucciones, particularmente en planos oblicuos, para identificar y analizar los diferentes reparos anatómicos del oído y alcanzar la visualización óptima de la anatomía relevante del hueso temporal.The ear is a complex anatomic structure. Its study and understanding represent a constant challenge for the radiologist. As a consequence the computed tomography becomes an essential tool for its examination. Conventional tomographic examination with both axial and coronal reconstruction of the image allows a satisfactory visualization of the different structures. However, the study requires long periods of time for its acquisition and uncomfortable or intolerable positions for the patients. Moreover, the characterization of some structures of the ear becomes limited. Sixty-four slice multidetector computed tomography allows the optimal study of the small and complex ear anatomy. Volumetric acquisitions with 0.5 mm slices, with multiplanar reconstructions in the three basic plans, in tri-dimensional reconstructions and curved plans, allow detailed visualization of structures in a few seconds, thuf avoiding patient discomfort. Our purpose in this article is to demonstrate the utility of reconstructions particularly in oblique planes, and reaching an optimal visualization of the temporal bone.

  17. Diagnostic accuracy of 16-row multislice CT angiography in the evaluation of coronary segments; Accuratezza diagnostica della coronarografia-TC a 16 strati nella valutazione dei segmenti coronarici

    Energy Technology Data Exchange (ETDEWEB)

    Cademartiri, Filippo [Erasmus Medical Center, Rotterdam (Netherlands). Dipartimento di Radiologia; Mollet, Nico R. [Erasmus Medical Center, Rotterdam (Netherlands). Dipartimento di Cardiologia; Runza, Giuseppe [Palermo Univ., Palermo (Italy). DIBIMEL Sezione di Scienze Radiologiche] [and others

    2005-02-01

    Purpose: To evaluate the diagnostic accuracy of 16-row multislice spiral computed tomography coronary angiography (16-MSCT-CA) for the non-invasive assessment of significant coronary artery stenosis. Materials and methods: We enrolled 40 patients (36 male, aged {+-} 11 yrs) with suspected obstructive coronary artery disease and a heart rate <65 bpm during the scan. The 16-MSCT-CA (Sensation 16, Siemens, Forcheim, Germany) was performed with electrocardiographic-gated technique after the intravenous administration of 100 ml of iodinated contrast material followed by a saline bolus chaser. The scan parameters were: collimation 16x0.75 mm, rotation time 0.42 s, feed/rot. 3 mm (pitch 0.25), 120 kVp, 500 mAs. All coronary segments {>=}2 mm in diameter were evaluated by two independent observers for the presence of significant coronary artery stenosis ({>=}50%). Consensus reading was compared to quantitative coronary angiography. Results: The average heart rate was 55{+-}6 bpm. Of the 428 segments of {>=}2.0 diameter 92 were significantly diseased. Without exclusion of any branches (428), the sensitivity, specificity, positive, and negative predictive values to identify {>=}50% obstructed segments were 95.7% (88/92), 95.8% (322/336). 86.3% (88/102), and 98.8% (322/326), respectively. No occluded left main, left anterior descending, circumflex or right coronary artery segments remained undetected. Conclusions: 16-MSCT-CA in a selected low-heart-rate patient population provides high diagnostic accuracy in the evaluation of significant coronary artery stenosis. [Italian] Scopo: Misurare l'accuratezza diagnostica della coronarografia-TC a 16 strati (16-AC-TCMS) nella valutazione non invasiva delle stenosi coronariche significative. Materiale e metodi: Quaranta pazienti (36 maschi, eta' 59{+-}11 anni) con sospetta malattia coronarica ostruttiva e con frequenza cardiaca durante la scansione <65bpm sono stati arruolati per lo studio . La 16-AC-TCMS (Sensation 16

  18. Preoperative volume calculation of the hepatic venous draining areas with multi-detector row CT in adult living donor liver transplantation: impact on surgical procedure

    Energy Technology Data Exchange (ETDEWEB)

    Frericks, Bernd B.J. [Hanover Medical School, Departments of Radiology and Surgery, Hannover (Germany); University of Berlin, Department of Radiology, Berlin (Germany); Charite - University Medicine Berlin, Department of Radiology and Nuclear Medicine, Berlin (Germany); Kirchhoff, Timm D.; Shin, Hoen-Oh; Stamm, Georg; Merkesdal, Sonja; Abe, Takehiko; Galanski, Michael [Hanover Medical School, Departments of Radiology and Surgery, Hannover (Germany); Hanover Medical School, Department of Diagnostic Radiology, Hannover (Germany); Schenk, Andrea; Peitgen, Heinz-Otto [Hanover Medical School, Departments of Radiology and Surgery, Hannover (Germany); MeVis - Center for Medical Diagnostic Systems and Visualization, Bremen (Germany); Klempnauer, Juergen [Hanover Medical School, Departments of Radiology and Surgery, Hannover (Germany); Hanover Medical School, Department of Visceral- and Transplantation Surgery, Hannover (Germany); Nashan, Bjoern [Hanover Medical School, Departments of Radiology and Surgery, Hannover (Germany); Hanover Medical School, Department of Visceral- and Transplantation Surgery, Hannover (Germany); Dalhousie University, Multi Organ Transplant Program, Halifax, Nova Scotia (Canada)

    2006-12-15

    The purpose was to assess the volumes of the different hepatic territories and especially the drainage of the right paramedian sector in adult living donor liver transplantation (ALDLT). CT was performed in 40 potential donors of whom 28 underwent partial living donation. Data sets of all potential donors were postprocessed using dedicated software for segmentation, volumetric analysis and visualization of liver territories. During an initial period, volumes and shapes of liver parts were calculated based on the individual portal venous perfusion areas. After partial hepatic congestion occurring in three grafts, drainage territories with special regard to MHV tributaries from the right paramedian sector, and the IRHV were calculated additionally. Results were visualized three-dimensionally and compared to the intraoperative findings. Calculated graft volumes based on hepatic venous drainage and graft weights correlated significantly (r=0.86,P<0.001). Mean virtual graft volume was 930 ml and drained as follows: RHV: 680 ml, IRHV: 170 ml (n=11); segment 5 MHV tributaries: 100 ml (n=16); segment 8 MHV tributaries: 110 ml (n=20). When present, the mean aberrant venous drainage fraction of the right liver lobe was 28%. The evaluated protocol allowed a reliable calculation of the hepatic venous draining areas and led to a change in the hepatic venous reconstruction strategy at our institution. (orig.)

  19. Biomechanics of Rowing

    Science.gov (United States)

    Hase, Kazunori; Kaya, Motoshi; Yamazaki, Nobutoshi; Andrews, Brian J.; Zavatsky, Amy B.; Halliday, Suzanne E.

    Compared with the other exercise, such as walking and cycling, rowing was expected to have some fitness advantage, while there were some misgivings about the risk of injury. The objectives of this study were to quantify biomechanical characteristics of rowing for fitness and rehabilitation and to offer normative data for the prevention of injury and for determining effective exercise. An experiment was performed to collect the kinematic and kinetic data during rowing by experienced and non-experienced subjects. A three-dimensional whole-body musculo-skeletal model was used to calculate the biomechanical loads, such as the joint moments, the muscular tensions, the joint contact forces and the energy consumption. The results of this study indicate that rowing is an effective exercise for rehabilitation and fitness. However, the non-experienced rower should acquire considerable skill to obtain sufficient exercise. The rowing cadence should be decided according to the purpose of the exercise.

  20. Clinical Value of Combined 320-row CT Volume Scanning and MRI for Sacroiliac Joint Lesion in Patients with Early Ankylosing Spondylitis%320排CT容积扫描结合MRI诊断早期强直性脊柱炎骶髂关节病变的临床价值

    Institute of Scientific and Technical Information of China (English)

    杨林根; 彭晋; 吴贵华; 耿方明; 饶志远

    2012-01-01

    Objective To study CT and MRI features of the sacroiliac joint lesion in the patients with early ankylosing spondylitis(AS) and evaluate the value of combined 320-row CT volume scanning and MRI for early AS. Methods Sixty patients suspected with AS underwent 320-row CT volume scanning for sacroiliac joint, of which, 10 ones diagnosed with AS by CT went through MRI examination. The changes of the sacroiliac joints of the 60 ones were analyzed retrospectively, and the imaging features of the sacroiliac joints of early AS were summarized. Results It's proved that 320-row CT volume scanning could display the minimal changes of bone structure and MRI gained its advantages for the examination of articular cartilage, synovial membrane and hone marrow. Conclusion The combined 320—row CT volume scanning and MRI are of great clinical value for the sacroiliac joint lesion of early AS.%目的:分析早期强直性脊柱炎骶髂关节病变的CT及MRI表现,评价320排CT容积扫描结合MRI对早期强直性脊柱炎的诊断价值.方法:对60例临床拟诊为强直性脊柱炎的患者行骶髂关节320排CT容积扫描,其中10例CT可疑病例行MR检查.回顾分析60例患者的骶髂关节特征性改变,归纳早期强直性脊柱炎骶髂关节病变的影像学特点.结果:320排CT容积扫描能清晰显示骶髂关节微细骨质结构改变,MRI能清晰显示骶髂关节软骨、滑膜、骨髓等异常改变.结论:320排CT容积扫描结合MRI对早期强直性脊柱炎骶髂关节病变的诊断有较高的临床应用价值.

  1. Comparative assessment of image quality for coronary CT angiography with iobitridol and two contrast agents with higher iodine concentrations: iopromide and iomeprol. A multicentre randomized double-blind trial

    Energy Technology Data Exchange (ETDEWEB)

    Achenbach, Stephan [Friedrich-Alexander-Universitaet Erlangen-Nuernberg, Department of Cardiology, Erlangen (Germany); Paul, Jean-Francois [Centre Chirurgical Marie Lannelongue, Department of Radiology, Le Plessis Robinson (France); Laurent, Francois [University of Bordeaux, Centre de Recherche Cardio-Thoracique de Bordeaux, U1045, Bordeaux (France); CHU de Bordeaux, Service d' Imagerie Thoracique et Cardiovasculaire, Pessac (France); Becker, Hans-Christoph [University Hospital Grosshadern, Department of Clinical Radiology, Munich (Germany); Rengo, Marco [Sapienza - University of Rome, ICOT Hospital, Department of Radiological Sciences, Oncology and Pathology, Latina (Italy); Caudron, Jerome [University Hospital of Rouen, Department of Radiology, Rouen (France); Leschka, Sebastian [Saint Gallen Hospital, Department of Radiology, Saint Gallen (Switzerland); Vignaux, Olivier [Cochin Hospital, Department of Radiology, Paris (France); Knobloch, Gesine [La Charite, Department of Radiology, Berlin (Germany); Benea, Giorgio [Ospedale del Delta, Ferrara (Italy); Schlosser, Thomas [Elisabeth-Krankenhaus Hospital, Essen (Germany); Andreu, Jordi [Hospital Vall d' Hebron, Barcelona (Spain); Cabeza, Beatriz [Hospital Clinico San Carlos, Madrid (Spain); Jacquier, Alexis [La Timone Adult Hospital, Department of Radiology, Marseille (France); Souto, Miguel [Complejo Hospitalario Universitario, Santiago de Compostela (Spain); Revel, Didier [Louis Pradel Hospital, Department of Radiology, Lyon (France); Qanadli, Salah Dine [University of Lausanne, Department of Radiology, Lausanne (Switzerland); Cademartiri, Filippo [Giovanni XXIII Hospital, Department of Radiology, Monastier di Treviso (Italy); Collaboration: X-ACT Study Group

    2017-02-15

    To demonstrate non-inferiority of iobitridol 350 for coronary CT angiography (CTA) compared to higher iodine content contrast media regarding rate of patients evaluable for the presence of coronary artery stenoses. In this multicentre trial, 452 patients were randomized to receive iobitridol 350, iopromide 370 or iomeprol 400 and underwent coronary CTA using CT systems with 64-detector rows or more. Two core lab readers assessed 18 coronary segments per patient regarding image quality (score 0 = non diagnostic to 4 = excellent quality), vascular attenuation, signal and contrast to noise ratio (SNR, CNR). Patients were considered evaluable if no segment had a score of 0. Per-patient, the rate of fully evaluable CT scans was 92.1, 95.4 and 94.6 % for iobitridol, iopromide and iomeprol, respectively. Non-inferiority of iobitridol over the best comparator was demonstrated with a 95 % CI of the difference of [-8.8 to 2.1], with a pre-specified non-inferiority margin of -10 %. Although average attenuation increased with higher iodine concentrations, average SNR and CNR did not differ between groups. With current CT technology, iobitridol 350 mg iodine/ml is not inferior to contrast media with higher iodine concentrations in terms of image quality for coronary stenosis assessment. (orig.)

  2. Rowing with FES

    Directory of Open Access Journals (Sweden)

    Davoodi Rahman

    2008-01-01

    Full Text Available People with spinal cord injury (SCI need to increase their level of physical activity to reduce the risk of cardiovascular disease but their exercise options are very limited. Functional electrical stimulation (FES assisted indoor rowing has been developed as a total body exercise option that combines the exercise of the innervated upper body with the exercise of the electrically stimulated leg muscles in a natural manner. An existing indoor rowing machine was modified for use by the paraplegic users and two types of FES controllers were developed to control the level of stimulation to the paralyzed leg muscles. Manual FES controller was operated by the users thumb presses on the two control buttons on the handlebar, was easy to implement and operate, and has been the most widely used form of control in FES rowing. Automatic FES controllers produced rowing movement comparable to manual control strategy but did not require the user's thumb presses, could be used by the users with higher level of SCI, and could potentially be used to control more leg muscles to further increase the intensity and cardiovascular training effects of FES rowing exercise.

  3. Scottish Short Stone Rows

    Science.gov (United States)

    Ruggles, Clive L. N.

    Short stone rows received a good deal of attention during the 1980s and 1990s, at a time when archaeoastronomy in prehistoric Britain and Ireland was moving beyond reassessments of Alexander Thom's "megalithic observatories" by identifying coherent groups of similar monuments with clear orientation trends. Many such rows are found in western Scotland, with the main concentration in Argyll and the island of Mull. Systematic analyses of their orientations produced credible evidence of an awareness of the 18.6-year lunar node cycle, within a "primary-secondary" pattern whereby isolated rows were oriented close to moonrise or moonset at the southern major standstill limit, while others oriented in this way were accompanied by a second row oriented in a declination range that could be interpreted either as lunar or solar. A detailed investigation of the landscape situation of the sites in northern Mull, accompanied by excavations at two of the sites, suggested that they were deliberately placed in locations where critical moonsets would be seen against prominent distant landscape features, but where the distant horizon in most or all other directions was hidden from view. A lack of independent archaeological evidence may help to explain why archaeoastronomical investigations at short stone rows have never progressed beyond "data-driven" studies of orientations and landscape situation. Nonetheless, the work that was done at these sites raised important general methodological issues, and pioneered techniques, that remain relevant across archaeoastronomy today.

  4. Hereditary haemorrhagic telangiectasia: study of hepatic vascular alterations with multi-detector row helical CT and reconstruction programs; Telangiectasia emorragica ereditaria: TC multidetettore multifasica e programmi di ricostruzione nello studio delle alterazioni vascolari epatiche

    Energy Technology Data Exchange (ETDEWEB)

    Memeo, Maurizio; Stabile Ianora, Amato Antonio; Scaldapane, Arnaldo; Rotondo, Antonio; Angelelli, Giuseppe [Policlinico Universitario, Bari (Italy). DiMIMP Sezione di Diagnostica per Immagini; Suppressa, Patrizia; Cirulli, Anna; Sabba' , Carlo [Policlinico Universitario, Bari (Italy). Centro Interdipartimentale per lo studio dell' HHT

    2005-02-01

    Purpose: To evaluate hepatic alterations in patients affected by Hereditary Haemorrhagic Telangiectasia (HHT) by using multidetector row helical CT (MDCT) and new reconstruction programs. Materials and methods: An MDCT multiphasic study of the liver was performed in 105 consecutive patients: 89 considered to be affected by HHT and 16 with suspicion of disease alone. The scan delay was determined by using a test bolus of contrast material. The CT examination was performed with a triphasic technique (double arterial phase and portal venous phase). multiplanar and angiographic reconstructions were then obtained, and the images checked for the presence of shunts, hepatic perfusion disorders, vascular lesions (telangiectasis and large confluent vascular masses), indirect signs of portal hypertension, and anatomical vascular variants. Results: Hepatic vascular alterations were found in 78/105 cases (67/89) patients affected by HHT and 11/16 patients with clinical suspicion alone). Therefore HHT diagnosis was excluded in 5 patients. 78/100 (78%) patients with HHT had intrahepatic vascular alterations: arterioportal shunts in 40/78 (51.2%) arteriosystemic shunts in 16/78 (20.5%) and both shunt types in 22/78 (28.3%). Intraparenchymal perfusion disorders were found in 46/78 (58.9%) patients. Telangiectasis were recognised in 50/78 (64.1%) patients. Large confluent vascular masses (LCVMs) were identified in 20/78 (25.6%) patients. indirect signs of portal hypertension were found in 46/78 (58.9%) cases. Variant hepatic arterial anatomy was present in 38/100 cases (38%). Conclusions: Multiphasic MDCT and the new reconstruction programs enable the identification and characterisation of the complex vascular alterations typical of HHT. [Italian] Scopo: Valutare le alterazioni epatiche nei pazienti affetti da Telangiectasia Emorraica Ereditaria (TEE) utilizzando una TC multidetettore (TCMD) ed in nuovi programmi di ricostruzione. Materiale e metodi: E' stato eseguito uno

  5. Application of Whole-brain Perfusion CT with 320-detector Row CT System in Staging of Cerebral Ischemic Penumbra%320排动态容积CT全脑灌注成像在脑梗死缺血半暗带分期中的应用

    Institute of Scientific and Technical Information of China (English)

    向永华; 王波; 金科; 杨伟; 汪春红

    2012-01-01

    Purpose To investigate the feasibility of staging cerebral ischemic penumbra using 320-detector row CT whole-brain perfusion imaging. Materials and Methods The values of cerebral blood volume (CBV), cerebral blood flow (CBF), mean transit time (MTT) and time to peak (TTP) were measured in infarct core area, ischemic penumbra, and mirror area in 18 cases with ischemic penumbra. The staging of the ischemic penumbra was made according to the criteria of pre-infarction period staging. Results In 18 cases with ischemic penumbra, MTT and TTP were delayed; CBF was decreased; CBV was slightly decreased, normal or slightly increased. Compared with infarct core area, CBV and CBF were increased, MTT was delayed and TTP was shortened in ischemic penumbra (P 0.05). In 18 cases, three cases were in stage I 2, nine cases in stage Ⅱ1, six cases in stage Ⅱ2. Conclusion Application of whole-brain perfusion CT with 320-detector row CT system can identify the area of cerebral lesions and the existence of ischemic penumbra.%目的 应用320排动态容积CT全脑灌注成像探讨脑梗死缺血半暗带分期的可行性.资料与方法 测量18例存在缺血半暗带脑梗死患者的梗死核心区、缺血半暗带区及其镜像对侧脑血容量(CBV)、脑血流量(CBF)、平均通过时间(MTT)及达峰时间(TTP),按脑梗死前期分期标准对缺血半暗带进行分期.结果 18例缺血半暗带区表现为MTT、TTP延长,CBF降低,CBV轻度升高、正常或轻度降低.与梗死核心区比较,缺血半暗带区CBV、CBF升高,MTT延长,TTP缩短(P<0.05);与健侧对应区比较,CBF降低,MTT及TTP延长(P<0.05),而CBV无显著差异(P>0.05).缺血半暗带分期:Ⅰ2期3例,Ⅱ1期9例,Ⅱ2期6例.结论 应用320排动态容积CT全脑灌注成像可明确脑梗死患者的病变部位、范围以及有无缺血半暗带存在,并可对缺血半暗带进行分期.

  6. Application and its clinical significance of 16 row spiral CT enhanced scanning in the diagnosis of pulmonary embolism%16排螺旋CT增强扫描在肺动脉栓塞诊断中的应用及其临床意义

    Institute of Scientific and Technical Information of China (English)

    杨震杰

    2015-01-01

    Objective:To explore the application and its clinical significance of 16 row spiral CT enhanced scanning in the diagnosis of pulmonary embolism.Methods:28 patients with pulmonary embolism were selected from May 2011 to April 2014.They were diagnosed using 16 slice spiral CT enhanced scan.We evaluated the clinical application.Results:By 16 slice spiral CT scan, we could find out the exact location and morphology of pulmonary embolism.Conclusion:The 16 row spiral CT scan can clearly diagnose pulmonary embolism,and timely provide the advantageous basis for treatment,and it has important clinical significance.%目的:探讨16排螺旋CT增强扫描在肺动脉栓塞诊断中的应用及其临床意义.方法:2011年5月-2014年4月收治肺动脉栓塞患者28例,采用16排螺旋CT增强扫描后进行肺动脉栓塞的诊断,并对其在临床上的应用进行评价.结果:经过16排螺旋CT扫描能准确找出肺动脉栓塞发生的部位和形态.结论:采用16排螺旋CT增强扫描能明确诊断肺动脉栓塞的情况,并为治疗提供及时有利的依据,具有重要的临床意义.

  7. Evaluation of retrospectively ECG-gated 4-row multidetector CT in patients planned for minimal invasive coronary artery bypass grafting; Die EKG-getriggerte 4-Zeilen-Spiral-CT des Herzens in der praeoperativen Bildgebung vor minimalinvasiver koronarer Bypass-Operation

    Energy Technology Data Exchange (ETDEWEB)

    Begemann, P.G.C.; Ittrich, H.; Koops, A.; Adam, G.; Weber, C. [Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie, Radiologisches Zentrum, Universitaetsklinikum, Hamburg (Germany); Arnold, M.; Detter, C.; Boehm, D.H.; Reichenspurner, H. [Universitaetsklinikum Hamburg-Eppendorf, Herzzentrum, Herz und Gefaesschirurgie, Hamburg (Germany)

    2005-08-01

    Purpose: Minimal invasive direct coronary artery bypass grafting (MIDCAB) or off-pump coronary artery bypass grafting (OPCAB) on the beating heart with full or mini-sternotomy are becoming more common in coronary bypass surgery of the left anterior descending (LAD). In the decision, which surgical approach (MIDCAB, OPCAB or conventional surgery with cardiopulmonary bypass) will be best used, knowledge of the anatomical field is of major importance. The aim of the study was to evaluate retrospective ECG-gated 4-row multidetector CT (MDCT) in patients planned for MIDCAB as additional imaging to coronary angiography. Material and methods: The study included 25 consecutive patients. MSCT was performed as unenhanced (collimation 4 x 2.5 mm) and contrast-enhanced examination (140-170 ml, 300 mg Iodine/ml, collimation 4 x 1 mm). The evaluation included presence of LAD calcifications, distance of LAD and left internal mammarian artery (LIMA), coursek of LAD and LIMA, the presence or absence of bridging through myocardium or epicardial fat and the presence of pleural fibrosis. The MDCT results were correlated with intra-operative findings. Results: All MDCTs could be assessed with reference to the demands. In 20/25 operations, MDCT had direct influence as to the selection of the surgical approach (11 MIDCAB, 7 OPCAB with mini-sternotomy and 5 with full sternotomy, 2 conventional surgeries). The distance of LAD and LIMA varied from 0.9 to 4.5 cm in MDCT. As to calcifications, 3/25 correlated patients had calcifications and 10 patients had no calcifications in the middle LAD. Seven patients had intraoperative fibrosis of the vessel wall without calcification of the middle LAD, which could not be detected with MDCT. Another 5 patients had single calcified plaques in the middle LAD, 4 of these had a fibrosis of the vessel and 1 had a normal vessel at surgery. In these cases, the anastomosis was done between the calcified plaques. No myocardial bridging was detected by MDCT and

  8. 64 row CT cerebral perfusion applied research of brain ischemia%64排CT脑灌注对脑组织缺血程度的应用研究

    Institute of Scientific and Technical Information of China (English)

    刘贯清; 肖新兰; 李晓; 黄小宁; 李五根

    2015-01-01

    Objective Application of 64 row CT cerebral perfusion brain tissue ischemia. Methods 40 cases of clinical diag-nosis of acute cerebral infarction,patients with unilateral lobe brain perfusion CT perfusion showed abnormal,in combination with MRI to determine infarct,according to the cerebral blood flow group,group A (low perfusion group) and group B (infarction group), respectively,evaluation of two groups of cerebral blood flow perfusion parameters and comparison analysis. Results Of 40 cases, 18 cases of group A,CTP anomaly low perfusion of figure is determined by MTT extend approximately 1.28 (R),decreased CBF mild,CBV basic no change Or moderately reduced,only determined by MTT extension was statistically significant (P<0.01);Infarc-tion group,22 cases of group B,infarction area surrounding IP abnormal perfusion is determined by MTT extend approximately 1. 48(R),CBF significantly decreased approximately 0.45(R),CBV moderately reduced,which extended determined by MTT was sta-tistically significant (P<0.001),decrease CBF was statistically significant (P<0.01);Infarction district performance is determined by MTT extend approximately 1.64(R),CBF significantly decreased approximately 0.36(R),significantly lower CBV (approximately 0. 37)R. Which determined by MTT extension was statistically significant (P<0.001),CBF decline was statistically significant(P<0.01). Conclusion Brain tissue hypoperfusion area with the infarction in central and peripheral IP area the perfusion parameters have significant differences,according to the variation of perfusion parameters characteristics can make the image on the degree of is-chemic infarction assessment,when rCBF<0.5,suggesting infarction risk is extremely high,the clinical guidance for early interven-tion treatment.%目的:探讨应用64排CT脑灌注评价脑组织缺血程度。方法40例临床诊断急性脑梗塞,CT灌注显示单侧脑叶灌注异常患者,结合MRI判断梗塞,根据脑血流量进行分组,A

  9. Study on the decrease in scanning radiation of 64 Row of Spiral CT in the Skull & brain of newborn%多排 CT 低剂量不同扫描方法在新生儿颅脑检查中应用

    Institute of Scientific and Technical Information of China (English)

    赵明增

    2013-01-01

    Objective Study the lowest parameter of scanning radiation in 64 Row of Spiral CT used in Skull& brain of newborn ,aiming to decrease radiation .Methods To find the best method and the lowest parameter used in Skull& brain of newborn ,spiral scanning and section scan-ning were used by gradually decreasing scanning parameter .KVP was fixed at 120 KV ,other scanning parameter were gradually decreased by 10mAs .low dose group of section scanning began from 120KV .60mAs ,low dose group of spiral scanning began from120KV .90mAs .20 newborn were scanned at each group ,images of each group were by three image diagnosis expert with senior title ,according to image definition ,gradation and contrast ,concrete anatomy structure in brain tissue ,ventricle ,sulcus as well as detectabilities of lesions ,divided into five levels ,named as high ,good ,general ,poor ,worse quality . ,scored 5 ,4 ,3 ,2 ,1respectively .3 and above 3 were thought as qualified .Results 120KVP .70mAs is the lowest scanning parameter accesable in 64 Row of Spiral CT .120KVP .30mAs is the lowest scanning parameter accesable in section scanning . cmin section scanning .the scanning parameter of two group is 47% and 40% to general scanning respectively .Theparameter in section scanning is 31% to that of spiral scanning .Accordingly ,.Conclusion The best method in 64 Row of Spiral CT used in skull& brain of newborn is section scanning .the lowest scanning parameter is 120KV .40mAs.%目的:探讨多排CT低剂量不同扫描方法在新生儿颅脑检查中的应用,用最佳的检查方法,最小辐射剂量,减少辐射损害。方法用螺旋和横断两种不同扫描方式,采用逐渐降低扫描参数方法,得出新生儿颅脑多排C T扫描可用的最佳方法和最低扫描参数。固定KVP值120 KV和其他扫描参数,每次降低10 mAs。横断法低剂量组扫描参数从120 KVP .60 mAs开始,螺旋法低剂量组扫描参数从120 KV .90 mAs开始。每组扫描20例

  10. Measures of rowing performance.

    Science.gov (United States)

    Smith, T Brett; Hopkins, Will G

    2012-04-01

    Accurate measures of performance are important for assessing competitive athletes in practi~al and research settings. We present here a review of rowing performance measures, focusing on the errors in these measures and the implications for testing rowers. The yardstick for assessing error in a performance measure is the random variation (typical or standard error of measurement) in an elite athlete's competitive performance from race to race: ∼1.0% for time in 2000 m rowing events. There has been little research interest in on-water time trials for assessing rowing performance, owing to logistic difficulties and environmental perturbations in performance time with such tests. Mobile ergometry via instrumented oars or rowlocks should reduce these problems, but the associated errors have not yet been reported. Measurement of boat speed to monitor on-water training performance is common; one device based on global positioning system (GPS) technology contributes negligible extra random error (0.2%) in speed measured over 2000 m, but extra error is substantial (1-10%) with other GPS devices or with an impeller, especially over shorter distances. The problems with on-water testing have led to widespread use of the Concept II rowing ergometer. The standard error of the estimate of on-water 2000 m time predicted by 2000 m ergometer performance was 2.6% and 7.2% in two studies, reflecting different effects of skill, body mass and environment in on-water versus ergometer performance. However, well trained rowers have a typical error in performance time of only ∼0.5% between repeated 2000 m time trials on this ergometer, so such trials are suitable for tracking changes in physiological performance and factors affecting it. Many researchers have used the 2000 m ergometer performance time as a criterion to identify other predictors of rowing performance. Standard errors of the estimate vary widely between studies even for the same predictor, but the lowest

  11. Honor on Death Row

    Directory of Open Access Journals (Sweden)

    Judy Eaton

    2014-04-01

    Full Text Available The Southern United States is described as having a culture of honor, an argument that has been used to explain higher crime rates in the Southern United States than in the rest of the country. This research explored whether the combination of honor-related violence and traditional southern politeness norms is related to regional differences in the degree of remorse expressed by those who have committed violent crimes. It was proposed that different social norms regarding politeness and apologies in the Southern United States would be reflected in the narratives provided by offenders. The data came from the final statements that offenders on death row made before they were executed. Results showed that, compared with offenders executed in the non-Southern United States, offenders executed in the South more often apologized for their crimes in their final statements, but they were not necessarily more remorseful.

  12. Clinical Application Value of 64 Row Multislice CT Three-Dimensional and Reconstruction Techniques in the Diagnosis of Rib Fracture%64排多层螺旋CT三维及重建技术在诊断肋骨骨折中的临床应用价值

    Institute of Scientific and Technical Information of China (English)

    高英超; 邹璨

    2016-01-01

    Objective To study the diagnostic value of 64 row multislice CT three-dimensional and reconstruction techniques in the diagnosis of rib fracture.MethodsUsing MSCT scanning on 117 cases of patients with chest trauma, and conducted image reconstruction by CT, MPR and VR technologies, and compared with common CT scan and DR.Results MSCT diagnosed rib fractures correctly in 176 cases, the detection rate was 100%. ConclusionMSCT, MPR and 3 D reconstruction can show the morphology, content and displacement of rib fractures clearly.%目的:评定对肋骨骨折患者诊断工作中,推行64排多层螺旋CT三维及重建技术的可行性。方法采取MSCT方案对117例胸部外伤患者进行扫描,运用CT、MPR及VR等技术进行图像重建并观察和分析,并与DR及普通CT所见进行对照分析。结果 MSCT正确诊断肋骨176处骨折,检出率100%。结论 MSCT、MPR及三维重建能够立体地显示肋骨骨折的部分、形态、骨折程度、骨折移位的特点等空间信息。

  13. MR angiography and determination of the flow reserve after minimal invasive direct coronary artery bypass (MIDCAB) surgery of the left internal mammary arteria in comparison to the multidetector-row CT; MR-Angiographie und Flussreservenbestimmung nach minimalinvasiver direkter Koronararterien-Bypass(MIDCAB)-Operation der linken Arteria mammaria interna im Vergleich zur Mehrzeilen-CT

    Energy Technology Data Exchange (ETDEWEB)

    Stauder, N.I.; Fenchel, M.; Kuettner, A.; Kramer, U.; Claussen, C.D.; Miller, S. [Abt. Radiologische Diagnostik, Universitaetsklinik Tuebingen (Germany); Stauder, H.; Scheule, A.M. [Abt. Thorax-, Herz- und Gefaesschirurgie, Universitaetsklinik Tuebingen (Germany)

    2005-08-01

    Purpose: To evaluate graft patency, flow and flow reserve in patients with minimal invasive direct coronary artery bypass (MIDCAB) of internal mammary artery (IMA) grafts using a combined MR protocol with phase-contrast technique and MR angiography. Material and methods: At a 1.5T Magnetom Sonata (SIEMENS), 19 symptomatic (angina CCS I-III, intermittent thoracic discomfort, scar disorders) patients (59.9{+-}7.9 years old) with 19 left internal mammary artery (LIMA) grafts implanted in minimal invasive technique were examined 6.9{+-}1.5 years post surgery. Contrast enhanced MR angiography (TR 2.5 ms, TE 1 ms, flip angle 20 , spatial resolution 1.4 x 0.9 x 1.0 mm{sup 3}, breath hold technique, no ECG-triggering, 25 ml Gd-DTPA) was performed to assess bypass patency. Phase-contrast flow measurements with retrospective gating (TR 41 msec, TE 3.2 msec, flip angle 30 , spatial resolution 1.1 x 1.1 x 5 mm{sup 3}, temporal resolution 42 msec, venc 90 cm/sec) were applied in the IMA grafts at rest and after stress induction with dipyridamole (0.56 mg/kg/BW). For comparison, graft patency was evaluated by multidetector-row computed tomography (16-row CT). In 9 patients a selective catheter angiography was performed. Results: MIDCAB grafts were occluded in 4/19 patients. In 4 patients the anastomosis to LAD was highly stenotic (>70%) at MDCT (2 experienced investigators in consensus reading). In MRA 9 grafts could be delineated completely including the distal anastomosis to LAD (47%). In 9 patients the distal part could not be evaluated. In patients with patent grafts (MDCT), a significant improvement of graft flow (at rest 75.4{+-}33.3 ml/min; after stress 202.7{+-}49.6; P<0.002) and flow reserve (patent grafts 3.0{+-}1.1; stenotic grafts 1.5{+-}0.2, P<0.02; occluded grafts 0.9{+-}0.2, P<0.01) after stress induction was detected. Diastolic-to-systolic peak velocity ratios (D/S-PVR) at baseline were not significant between patent and stenotic grafts. Mean flow at baseline and

  14. Training Rowing with Virtual Environments

    Directory of Open Access Journals (Sweden)

    Gopher Daniel

    2011-12-01

    Full Text Available This paper presents the results of the design, implementation and evaluation of a platform for rowing training in Virtual Reality called SPRINT. The paper discusses how various aspects of the rowing skill can be analyzed and trained over a single common methodology and system platform. The result is a vision for new directions in the domain of sport training with Virtual Reality.

  15. 64排螺旋CT在诊断成人冠状动脉-肺动脉瘘中的应用价值%Application Value of 64-Row Spiral CT in the Diagnosis of Coronary Artery-Pulmonary Artery Fistula in Adults

    Institute of Scientific and Technical Information of China (English)

    朱红伟

    2014-01-01

    Objective To explore the application value of 64-row spiral CT in the diagnosis of coronary artery-pulmonary artery ifstula in adults.Methods The CT images of 28 adults with coronary artery-pulmonary artery ifstula were retrospectively analyzed.Results Among 28 patients, 10 patients suffered from unilateral vessel lesions, while 18 patients suffered with bilateral vessel lesions. There were 24 patients whose diameter of artery ifstula blood vessels were smaller than that of initial coronary artery, accounting for 85.71%.While 4 patients whose diameter of artery fistula blood vessels were larger than that of initial coronary artery, accounting for 14.29%.Conclusion The 64-Row spiral CT which can clearly show the origin, course and termination of blood vessels, has a great clinical value in the diagnosis of coronary artery-pulmonary artery ifstula.%目的:探讨64排螺旋CT在诊断成人冠状动脉-肺动脉瘘中的应用价值。方法回顾性分析我院28例成人冠状动脉-肺动脉瘘的CT图像。结果28例冠状动脉-肺动脉瘘患者中,单侧分支血管参与者10例,双侧分支血管参与者18例。动脉瘘血管直径较起始冠状动脉直径小的患者有24例,占85.71%;动脉瘘血管直径较起始冠状动脉直径大的患者有4例,占14.29%。结论64排螺旋CT可清晰地显示血管的起源、走行和终止等情况,对冠状动脉-肺动脉瘘的诊断具有重要的临床应用价值。

  16. Clinical application with 16-row spiral CT in diagnosis of esophageal hiatal hernia%16层螺旋CT在食管裂孔疝诊断中的应用

    Institute of Scientific and Technical Information of China (English)

    黄婷

    2013-01-01

    目的:探讨16层螺旋CT在食管裂孔疝诊断中的应用价值.方法:回顾25例经胃镜、手术或上消化道造影证实的食管裂孔疝患者的16层螺旋CT资料并加以分析.结果:16层螺旋CT可以清晰显示食管裂孔疝的疝囊大小、部位、形态、密度、膈肌裂孔情况及病变与邻近结构的关系.结论:16层螺旋CT通过薄层断面和多平面重建技术(MPR)可以多角度显示疝囊及内容物,可为肿瘤性病变及其他不明原因膈肌膨隆的鉴别诊断提供有价值的诊断信息.%Objective: To investigate diagnostic value of 16 slice spiral CT in esophageal hiatal hernia. Methods: We reviewed 25 cases by gastroscope, operation or upper gastrointestinal radiography confirmed esophageal hiatal hernia in patients with 16 slice spiral CT data, and analyzed. Results: Image of 16 slice spiral CT could clearly show the esophageal hiatal hernia hernia sac size, position, shape, density, the diaphragmatic hiatus and pathological relationship with adjacent structures. Conclusion: 16 slice spiral CT through thin section and multiplanar reconstruction (MPR) can be multi-angle display hernia sac and contents, especially in the display of the diaphragmatic hiatus of broadening and lesions and their relation to the adjacent tissues have irreplaceable role.At the same time and neoplastic lesions and other unexplained diaphragm bulge in the differential diagnosis of provide valuable diagnostic information.

  17. Louisiana farm discussion: 8 foot row spacing

    Science.gov (United States)

    This year several tests in growers’ fields were used to compare traditional 6-foot row spacing to 8-foot row spacing. Cane is double-drilled in the wider row spacing. The wider row spacing would accommodate John Deere 3522 harvester. Field data indicate the sugarcane yields are very comparable in 8-...

  18. 320-row CT coronary angiography predicts freedom from revascularisation and acts as a gatekeeper to defer invasive angiography in stable coronary artery disease: a fractional flow reserve-correlated study

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Brian S.; Wong, Dennis T.L.; Cameron, James D.; Leung, Michael; Meredith, Ian T.; Nerlekar, Nitesh; Antonis, Paul; Harper, Richard; Malaiapan, Yuvaraj; Seneviratne, Sujith K. [Southern Health and Monash University, Monash Cardiovascular Research Centre, MonashHEART, Department of Medicine Monash Medical Centre (MMC), Melbourne (Australia); Leong, Darryl P. [University of Adelaide, Discipline of Medicine, Adelaide (Australia); Flinders University, Adelaide (Australia); Crossett, Marcus; Troupis, John [Southern Health and Monash University, Monash Cardiovascular Research Centre, MonashHEART, Department of Medicine Monash Medical Centre (MMC), Melbourne (Australia); Southern Health and Monash University, Department of Diagnostic Imaging, MMC, Melbourne (Australia)

    2014-03-15

    To determine the accuracy of 320-row multidetector coronary computed tomography angiography (M320-CCTA) to detect functional stenoses using fractional flow reserve (FFR) as the reference standard and to predict revascularisation in stable coronary artery disease. One hundred and fifteen patients (230 vessels) underwent M320-CCTA and FFR assessment and were followed for 18 months. Diameter stenosis on invasive angiography (ICA) and M320-CCTA were assessed by consensus by two observers and significant stenosis was defined as ≥50 %. FFR ≤0.8 indicated functionally significant stenoses. M320-CCTA had 94 % sensitivity and 94 % negative predictive value (NPV) for FFR ≤0.8. Overall accuracy was 70 %, specificity 54 % and positive predictive value 65 %. On receiver operating characteristic (ROC) curve analysis, the area under the curve (AUC) for CCTA to predict FFR ≤0.8 was 0.74 which was comparable with ICA. The absence of a significant stenosis on M320-CCTA was associated with a 6 % revascularisation rate. M320-CCTA predicted revascularisation with an AUC of 0.71 which was comparable with ICA. M320-CCTA has excellent sensitivity and NPV for functional stenoses and therefore may act as an effective gatekeeper to defer ICA and revascularisation. Like ICA, M320-CCTA lacks specificity for functional stenoses and only has moderate accuracy to predict the need for revascularisation. (orig.)

  19. Advanced Gastric Cancer: Differentiation of Borrmann Type IV versus Borrmann Type III by Two-Phased Dynamic Multi-Detector Row CT with Use of the Water Filling Method

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Dae Jung; Yu, Jeong Sik; Lee, Sang Min; Kim, Joo Hee; Chung, Jae Joon; Kim, Ki Whang [Dept. of Radiology, Yonsei University College of Medicine, Gangnam Severance Hospital, Seoul (Korea, Republic of); Kang, Hae Youn [CHA Bundang Medical Center, CHA University, Seongnam (Korea, Republic of)

    2013-02-15

    To characterize Borrmann type IV from Borrmann type III advanced gastric cancer (AGC) by two-phased multi-detector row computed tomography (MDCT) using the water filling method. A total of 143 patients (pathologically confirmed Borrmann type III and IV - 100 and 43 patients), who underwent preoperative MDCT, were enrolled. Two radiologists, retrospectively and independently, determined tumor enhancement pattern using a 5-grade scale without clinical information. A weighted kappa test was applied for interobserver variability. The score of tumor enhancement pattern correlated with Borrmann type as determined by Spearman's correlation coefficient. The accuracy of differentiation of Borrmann type using MDCT was determined by receiver operating characteristic curves. Interobserver agreement (weighted kappa = 0.683) was substantial. The tumor enhancement pattern score showed a significant correlation with Borrmann type (reviewer 1, r = 0.591, p < 0.001; reviewer 2, r = 0.616, p < 0.001). The accuracy for differentiation of Borrmann type on MDCT was 0.86 (p < 0.001) in both reviewers. The sensitivity and specificity of the diagnosis of Borrmann type IV were 79% and 82% in reviewer 1, and 88% and 78% in reviewer 2, respectively. Dual-phased MDCT using the water filling method can differentiate between Borrmann type IV and III AGC with high accuracy.

  20. Clinical application value of 64 row spiral CT to hypertension patients with coronary lesions and left heart function%64排螺旋CT对高血压患者冠脉病变及左心功能的临床应用价值

    Institute of Scientific and Technical Information of China (English)

    饶志荣; 李建胜; 傅晖; 杨友祥; 王宁生; 方快发

    2012-01-01

    Objective To explore the clinical value of 64 row spiral CT to disease characteristics of hypertension patients with coronary artery and evaluation of left heart function. Methods 120 patients with high blood pressure from September 2009 to December 2010 in our hospital were selected. According to the patient's blood pressure levels, all the patients were divided into three groups, high blood pressure level 1, level 2 and level 3 with 40 cases in each group, 40 healthy check-up patients were chosen as control group. 64 row spiral CT were used to cardiac imaging scan, the relationship on the disease characteristics of coronary artery, blood pressure and coronary artery disease and left heart function were analyzed. Results Mild and single pathological changes were found in high blood pressure level 1 group chiefly; double and three teams of lesions were found in high blood pressure level 3 group chiefly, the differences of LVEF.LVEDV.LVESV and LVMM among high blood pressure level 3 group and other groups were all statistically significant (all P < 0.05), except the LVSV. Conclusion The examination of 64 row spiral CT can make accurate judgement to the smooth and narrow degree of coronary artery patients, and can accurately evaluate left cardiac function, and can screen the patients in high blood pressure combined with suspected coronary heart disease.%目的 探讨64排螺旋CT对高血压患者冠状动脉病变特点以及左心功能评估的临床价值.方法 选择2009年9月~2010年12月我院收治的高血压患者120例,根据患者的血压水平将患者分为高血压1级、高血压2级以及高血压3级三组,每组各40例,另外选取健康体检者40例为对照组.使用64排螺旋CT进行心脏成像扫描,分析其冠状动脉的病变特点、血压与冠状动脉病变和左心功能的关系.结果 高血压1级组患者以轻度和单支病变为主,高血压3级阻患者双支和三支病变最多,且除

  1. Hemobilia in a child due to right hepatic artery pseudoaneurysm: Multidetector-row computed tomography demonstration

    Directory of Open Access Journals (Sweden)

    Nisar A Wani

    2011-01-01

    Full Text Available We present a case of a 12-year-old boy who developed upper gastrointestinal bleeding in the form of hematemesis and melena 1 month after blunt trauma to liver. Computed tomography (CT angiography with multidetector-row CT demonstrated pseudoaneurysm of right hepatic artery related to old liver laceration to be the cause of the bleeding. Pseudoaneurysm was resected using the roadmap provided by CT angiography findings.

  2. 多排螺旋CT对腮腺肿瘤的诊断价值(附13例报告)%Multiple Row Spiral CT Diagnostic Value of Parotid Tumors(with 13 Cases Report)

    Institute of Scientific and Technical Information of China (English)

    万玉珍; 董楠; 贾永庚

    2014-01-01

    目的:提高对腮腺肿瘤的CT诊断与鉴别诊断水平。方法回顾性分析13例腮腺肿瘤的CT表现和病理结果。结果腮腺混合瘤10例(共18个病灶),黏液表皮样癌1例,非霍奇金淋巴瘤1例,嗜酸性淋巴肉芽肿瘤1例。结论 CT征象可以为腮腺肿瘤的良恶性鉴别诊断提供有价值的依据,位于浅叶、边界清楚、类圆形或椭圆形的腮腺肿瘤多为良性肿瘤;反之,多为恶性肿瘤。%Objective To raise the level of diagnosis and differential diagnosis of parotid tumors.Methods The CT findings of 13 parotid tumors were retrospectively analyzed.Results 10 cases of parotid mixed tumor with 18 lesions, mucoepidermoid carcinoma in 1 case, non-Hodgkin's lymphoma in 1 case, eosinophilic lymphoid granuloma in 1 case.Conclusion CT imaging is can provide valuable basis on the benign and malignant differential diagnosis of parotid tumors. A parotid tumor located in the superficial lobe, with a round or oval contour and sharp margin, is more likely to be a benign tumor. Otherwise, it might be a malignant tumor.

  3. Application of 64-row spiral CT in the evaluation of invasion of trachea,bronchi,and hilar vessels in central type of lung cancer%MSCT在判断中央型肺癌对气管、支气管及肺门血管侵犯中的价值

    Institute of Scientific and Technical Information of China (English)

    黄宝泉; 郑悦; 张庆武; 曾向廷; 林惠如

    2013-01-01

    Objective: To investigate the value of 64 row spiral computed tomography (MSCT) in the diagnosis of tra chea,bronchi and hilar vascular invasion by central type of lung cancer (CLC). Methods:Seventy five cases of CLC under went MSCT examination with post processing techniques including multiplanar reformation (MPR) ,curved planar reforma tion (CPR) ,volume rendering (VR) ,minimum intensity projection (MinIP) ,maximum intensity projection (MIP) and CT virtual endoscopy (CTVE). The relationship of trachea,bronchi,pulmonary hilar vessels with the neoplasm was studied. Results :Invasion of trachea and bronchi by CLC included extraluminal compression type (38 cases,50. 7%) ,which was showed on CT as compression and/or invasion of bronchi led to uneven stenosis;infiltration of bronchial wall(28 cases,37.3%)12. 0%) showed as protruding of neoplasm into the lumen which led to eccentric stenosis of trachea/bronchi. Altogether 117 hilar vessels were invaded by CLC,of which,95 (81. 2%) could be assessed on CT,showing obvious narrowing or oblitera tion; blood vessels encircled by tumor (n = 12,10. 3%) , and tumor thrombosis (n=10,8. 5%). Conclusion: The anatomic features of trachea,bronchi,and hilar vessels and their spacial relationship with CLC could be accurately assessed on 64 row spiral CT with post processing techniques, which provides significant information in judging whether there are trachea, bronchi, and hilar vessel invasion by CLC.%目的:探讨64排螺旋CT及后处理技术在判断中央型肺癌(CLC)对气管、支气管及肺门血管侵犯中的价值.方法:75例经纤支镜或病理确诊的CLC患者行64排螺旋CT扫描,运用多平面重组、曲面重组、容积再现、最大密度投影、CT仿真内窥镜等后处理技术观察肿瘤与气管、支气管及肺门血管的关系.结果:肿瘤对气管、支气管的侵犯表现为管外压迫型38例(50.7%),CT表现为肿瘤压迫并侵犯支气管,管腔内呈不均匀狭窄;管壁浸润型(28

  4. 320排CT血管造影筛查老年消化道出血并冠心病的应用价值%Diagnostic value for gastrointestinal hemorrhage senile patients with potential coronary artery disease using 320-row coronary angiography with CT

    Institute of Scientific and Technical Information of China (English)

    刘琦; 郎勇; 陈晓琴; 李雪莲; 王岚; 周力

    2011-01-01

    Objective To assess the diagnostic value for gastrointestinal hemorrhage senile patients with potential coronary artery disease using 320-row coronary angiography with CT (CTA). Methods A total of 71 gastrointestinal bleeding senile patients without coronary heart disease (CHD) history were successively accepted conventional 12-director electrocardiogram (ECG) and 320-row CTA in two weeks from being admitted to hospital. Among those patients, 26 accepted the X-ray coronary angiography (CAG) examination in six weeks. The diagnostic values of each method were compared in diagnosing gastrointestinal hemorrhage patients with potential coronary artery disease. Results In all 71 patients, 29 (40.84%) who positive coronary heart disease (CHD) test results were obtained using 320-row CTA and only 19 ( 26. 76% ) were gotten using ECG. There was statistical significance between the two methods ( P 0.05 ) . For diagnosing CHD, CTA gained an accuracy of 96.15% ( sensitivity 100% and specificity 90. 91 % ). Conclusions Coronary 320-row CTA angiography can be used as one of the preferred method in diagnosing gastrointestinal hemorrhage senile patients with potential coronary artery disease.%目的 探讨心脏320排CT血管造影(CTA)筛查老年消化道出血并冠心病(CHD)的临床价值.方法 选择71例无CHD病史的老年消化道出血患者,入院后2周内依次行常规12导联心电图(ECG)、心脏320排CTA检查,其中26例入院6周内行冠脉造影(CAG)检查;比较各种方法筛查CHD的临床价值.结果 71例患者中,CTA检查示CHD阳性29例(40.84%),ECG检查示CHD阳性19例(26 76%),CTA检查诊断CHD的阳性率明显高于ECG(P <0.05).行CAG检查的26例患者中,CAG检查示CHD阳性15例(57.69%),CTA检查示CHD阳性16例(61 53%),两种方法诊断CHD的阳性率无统计学差异(P>0.05);CTA检查诊断CHD的灵敏度为100%,特异度为90.91%,阳性预测值为93.75%,阴性预测值为100%.结论 心脏320排CTA可作

  5. Slide-based ergometer rowing

    DEFF Research Database (Denmark)

    Vinther, Anders; Alkjær, T; Kanstrup, I-L

    2012-01-01

    Force production profile and neuromuscular activity during slide-based and stationary ergometer rowing at standardized submaximal power output were compared in 14 male and 8 female National Team rowers. Surface electromyography (EMG) was obtained in selected thoracic and leg muscles along...

  6. Comparison between multi-detector row CT angiography and Doppler ultrasound on detecting carotid artery wall thickness%多层螺旋CT与Doppler超声对颈动脉壁层厚度的对比性研究

    Institute of Scientific and Technical Information of China (English)

    赵刚; 查云飞; 王弘; 洪玮; 邱晓明; 王珍; 肖友梅

    2013-01-01

    Objective To explore the relationship and consistency between multi-detector row computed tomography angiography (MDCTA) and color Doppler ultrasound (CD-US) in measuring carotid artery wall thickness (CAWT) and intima-media thickness (IMT). Methods CAWT and IMT of 38 subjects were measured using MDCTA and CD-US, respectively. Linear correlation analysis was performed to analyze the correlation between the results from CAWT and IMT,and Bland-Altman statistics was employed to analyze the consistency between them. Results The IMT value measured by CD-US was (0.85+0.16) mm, and the CAWT value measured by MDCTA was (0.87.± 0.18) mm (P > 0.05), and there was a high degree of correlation between them (correlation coefficient was 0.958,P< 0.01). An excellent consistency between CAWT and IMT was found by Bland-Altman plot, with a bias of 0.026 mm and the limit of consistency from -0.023 to 0.075. Conclusions There were significant correlation and consistency between MDCTA and CD-US in detecting CAWT and IMT. As a more objective and comprehensive new method, MDCTA can replace CD-US in the evaluation of early carotid atherosclerosis.%目的:探讨多层螺旋CT血管造影(MDCTA)和彩色多普勒超声(CD-US)在检测颈总动脉壁厚度(CAWT)和颈总动脉内膜-中层厚度(IMT)中的相关性和一致性.方法:应用MDCTA和CD-US分别对38例受试者颈总动脉的CAWT和IMT进行检测,用Pearson直线相关分析比较CAWT和IMT的相关性,用Bland-Altman分析比较两者的一致性.结果:MDCTA测量的颈总动脉CAWT为(0.87±0.18)mm,CD-US测量的颈总动脉IMT为(0.85±0.16)mm,两者比较无统计学差异,有高度相关性,相关系数为0.958,P<0.01,Bland-Altman分析两者间存在良好一致性,偏倚为0.026 mm,一致性界限为-0.023 ~ 0.075.结论:MDCTA和CD-US在检测颈总动脉CAWT和IMT时存在良好的相关性和一致性,MDCTA可以替代CD-US,作为一种评价颈动脉早期粥样硬化的更加客观全面的新方法.

  7. 320排CT灌注成像在头面部皮瓣移植前血供评价方面的应用价值%Value of 320-detector row perfusion CT in the pre-transplantation evaluation of head and facial skin flaps

    Institute of Scientific and Technical Information of China (English)

    许开元; 肖丹丹; 王彬; 王春梅; 杨思奋; 张雪林; 高芳琴

    2014-01-01

    目的:应用320排动态容积灌注CT扫描技术分析其在评估头颈面部皮瓣血供中的价值。方法研究对象为2011年8月~2013年4月间行全脑灌注的患者,共576例患者行320排CT全脑灌注CT检查。所有纳入研究的患者均无颈外动脉系统异常,因其他原因行头颅灌注CT检查的患者。获得的容积灌注数据通过体部灌注软件进行分析,并测量扫描区域内不同皮瓣的血流量值。皮瓣的供血动脉也可同时获得。获得的容积扫描数据经后处理后得到伪彩图,可进行兴趣区灌注血流(BF)值测量,测量时尽可能避开血管。动态容积扫描技术同时可获得扫描区域的血管信息,为穿支皮瓣移植提供基本信息。结果测量所有患者头面部皮瓣的BF值,包括额部、眼睑、鼻背部、颊部、颞部、枕部、颈部皮瓣,BF值分别为(127±7.7)、(268.0±31.1)、(229.0±50.9)、(67.8±9.5)、(140.3±5.5)、(163.8±15.5)、(123.5±12.5)ml/min。不同区域的皮瓣血供差别较大,眼睑与鼻背部皮瓣BF值较高,颊部BF值较低。检查同时也可获得不同期相皮瓣供血动静脉的图像,显示率为100%。结论320排动态容积灌注扫描技术可为接受头面部自体皮瓣移植患者提供有效的术前血供评估。灌注与解剖图像的融合有助于皮瓣术前设计。%Objective To investigate the value of 320-detector row perfusion CT in the pre-transplantation evaluation of blood supply of head and facial flaps.Methods Whole-head perfusion CT was performed on 576 patients with normal external carotid arteries using a 320-detector row CT system from August 2011 to April 2013.The number of visible feeding arteries and draining veins in the skin flaps on CTA was recorded.Pseudo color map was generated from the volume data using the body perfusion software.Blood flow of each skin flap within the scan region was measured.Results The blood flow

  8. On row-by-row coding for 2-D constraints

    CERN Document Server

    Tal, Ido; Roth, Ron M

    2008-01-01

    A constant-rate encoder--decoder pair is presented for a fairly large family of two-dimensional (2-D) constraints. Encoding and decoding is done in a row-by-row manner, and is sliding-block decodable. Essentially, the 2-D constraint is turned into a set of independent and relatively simple one-dimensional (1-D) constraints; this is done by dividing the array into fixed-width vertical strips. Each row in the strip is seen as a symbol, and a graph presentation of the respective 1-D constraint is constructed. The maxentropic stationary Markov chain on this graph is next considered: a perturbed version of the corresponding probability distribution on the edges of the graph is used in order to build an encoder which operates in parallel on the strips. This perturbation is found by means of a network flow, with upper and lower bounds on the flow through the edges. A key part of the encoder is an enumerative coder for constant-weight binary words. A fast realization of this coder is shown, using floating-point arith...

  9. A New Submaximal Rowing Test to Predict 2,000-m Rowing Ergometer Performance

    NARCIS (Netherlands)

    Otter, Ruby T. A.; Brink, Michel S.; Lamberts, Robert P.; Lemmink, Koen A. P. M.

    2015-01-01

    Otter, RTA, Brink, MS, Lamberts, RP, and Lemmink, KAPM. A new submaximal rowing test to predict 2,000-m rowing ergometer performance. J Strength Cond Res 29(9): 2426-2433, 2015-The purpose of this study was to assess predictive value of a new submaximal rowing test (SmRT) on 2,000-m ergometer rowing

  10. Ergometer rowing with and without slides

    DEFF Research Database (Denmark)

    Larsen, Anders Holsgaard; Jensen, K

    2010-01-01

    A rowing ergometer can be placed on a slide to imitate 'on-water' rowing. The present study examines I) possible differences in biomechanical and physiological variables of ergometer rowing with and without slides and II) potential consequences on training load during exercise. 7 elite oars......-women rowed in a randomized order in a slide or stationary ergometer at 3 predefined submaximal and at maximal intensity. Oxygen uptake was measured and biomechanical variables of the rowing were calculated based upon handle force (force transducer) and velocity/length (potentiometer) of the stroke. Stroke...

  11. 64-Row Detector CT Angiography of Aortoiliac and Lower Extremity Arteries:Effect of Using a Monitoring Scan at Knee Level on Image Quality%64层螺旋CT下肢动脉血管造影:腘动脉监测触发对图像质量的影响

    Institute of Scientific and Technical Information of China (English)

    周淑琴; 彭振鹏; 周旭辉; 严超贵; 高樱; 林少春; 李树荣

    2011-01-01

    Purpose: To evaluate the effect of using a monitoring scan at knee level on image quality for 64 - row detector CT angiography of aortoiliac and lower extremity arteries.Methods: The study was performed with approval of the institutional review board and with informed consent of the subjects.A total of 62 subjects were included in this prospective study.The monitoring trigger was sited at knee level of the popliteal artery for CT angiography.Image analysis was performed as follows: Subjective evaluation of the image quality of aorto - iliac area, femoro - popliteal district and run - off vessels with VR and MIP reconstruction respectively; Calculation of the CT value of aorto - iliac area, femoro -popliteal district and run - off vessels; and evaluation of the data by variance analysis; Evalution of the distal arterial and venous visibility.Results: The monitoring scan at the level of the popliteal artery was unavailable in 1 case.The overall quality of VR images in 33 of the 61 patients (54.1%) were categorized as excellent, in 23(37.7% ) as good, in 4(6.6% ) as fair, and in 1(1.6% ) as poor, the rate of excellent and good was 91.8%; MIP images in 41(67.2%)as excellent, in 17(27.9%)as good, for 2(3.3%)as fair, and for 1(1.6%) as poor, the rate of excellent and good was 95.1%.There was a high consistency between two observers (VR: Kappa = 0.719; MIP: Kappa = 0.678).The mean CT values measured at aorto - iliac area, femoro - popliteal district and run - off vessels were 536.42Hu ± 99.68 Hu(352.43 ~ 742.71Hu),541.72Hu ± 119.05 Hu(338.38 ~ 800.75Hu) and 421.29Hu ± 97.15 Hu(264.58 ~ 739.00Hu), respectively.There were significant differences among these three segments(F = 25.25, P = 0.00).The rate of distal arterial and venous visibility were 98.9% (1531/1549)and 22.9% (14/61), respectively.Conclusion: Using a monitoring scan at knee level was useful for 64- row detector CT angiography of aortoiliac and lower extremity arteries

  12. 多排螺旋CT双动脉期增强扫描对比剂浓度对肝癌检出率的影响%Detection of Hepatocellular Carcinoma with Multi - detector Row CT by Using Double- arterial Phase Enhanced Scanning: Effect of Iodine Concentration of Contrast Material

    Institute of Scientific and Technical Information of China (English)

    周建收; 宦怡; 景建梅

    2011-01-01

    目的:通过多排螺旋CT双动脉期及门脉期增强扫描,以评估对比剂浓度对肝癌检出率的影响.方法:95例肝癌患者随机分为两组行多排螺旋CT肝脏平扫及双动脉期、门脉期增强扫描,其中一组(48例)注射碘帕醇370 mgI/ml( 1.5 ml/kg),另外一组(47例)注射碘帕醇300 mgI/ml (1.85ml/kg),均于30 s注射完毕.扫描后图像由放射科医生阅片并与病理结果进行对比,统计分析两组患者> 2cm及≤2cm的肝癌病灶的诊断敏感性.结果:95例患者中共证实有259个肝癌病灶,其中87个≤2cm,172个>2cm.对于≤2cm的病灶及所有病灶动脉早期及晚期370 mgI/ml组诊断敏感性高于300 mgI/ml组,差别有统计学意义;在门脉期两组患者的诊断敏感性无显著性差异.结论:高浓密度对比剂在动脉早期、晚期可提高肝癌的检出率,特别是对于较小的肝癌病灶(≤2cm).%Purpose: To evaluate the effect of iodine concentration of contrast material on detection of hepatocellular carcinoma (HCC) with multi - detector row CT by using double - arterial phase and portal venous phase enhanced scanning. Methods: Ninety - five patients with HCC were examined by hepatic plain CT and contrast - enhanced CT including early arterial phase(EAP), late arterial phase (LAP) and hepatic parenchymal phase (HPP) scanning prospectively. Patients were randomized into two groups to receive Iopamidol 370 mgl/ml (48 patients, 1.5 ml/kg body weight) and 300 mg I/ml (47 patients, 1.85 ml/ kg body weight) respectively with a fixed injection duration of 30 seconds. The images were interpreted by radiologists and the CT results were compared with the pathological results. The detection sensitivity for tumors of two size categories (=£ 2 cm or > 2 cm) and iodine concentration groups were calculated and analyzed.Results: A total of 259 lesions were detected with 87 less than 2 cm in size and 172 larger than 2cm in size.For EAP and LAP, the sensitivity of Iopamidol 370

  13. Comparison of the Diagnostic Image Quality of the Canine Maxillary Dentoalveolar Structures Obtained by Cone Beam Computed Tomography and 64-Multidetector Row Computed Tomography.

    Science.gov (United States)

    Soukup, Jason W; Drees, Randi; Koenig, Lisa J; Snyder, Christopher J; Hetzel, Scott; Miles, Chanda R; Schwarz, Tobias

    2015-01-01

    The objective of this blinded study was to validate the use of cone beam computed tomography (C) for imaging of the canine maxillary dentoalveolar structures by comparing its diagnostic image quality with that of 64-multidetector row CT Sagittal slices of a tooth-bearing segment of the maxilla of a commercially purchased dog skull embedded in methylmethacrylate were obtained along a line parallel with the dental arch using a commercial histology diamond saw. The slice of tooth-bearing bone that best depicted the dentoalveolar structures was chosen and photographed. The maxillary segment was imaged with cone beam CT and 64-multidetector row CT. Four blinded evaluators compared the cone beam CT and 64-multidetector row CT images and image quality was scored as it related to the anatomy of dentoalveolar structures. Trabecular bone, enamel, dentin, pulp cavity, periodontal ligament space, and lamina dura were scored In addition, a score depicting the evaluators overall impression of the image was recorded. Images acquired with cone beam CT were found to be significantly superior in image quality to images acquired with 64-multidetector row CT overall, and in all scored categories. In our study setting cone beam CT was found to be a valid and clinically superior imaging modality for the canine maxillary dentoalveolar structures when compared to 64-multidetector row CT.

  14. Wannseebahn row houses, Berlin, Germany

    Energy Technology Data Exchange (ETDEWEB)

    Erhorn, H.

    1999-07-01

    The energy-saving concept of the four Wannseebahn row houses in Berlin comprises a compact construction method, good thermal insulation of the building envelope, deliberate use of solar energy with south-facing windows and sunspaces, and a solar air system. The energy gained by the air collectors is led through a closed cycle and released to the middle wall of the building. So that the stored energy is used in a controlled manner, there is a second closed air cycle with an active discharge. (author)

  15. CT urography

    Energy Technology Data Exchange (ETDEWEB)

    Korobkin, M. [Dept. of Radiology, Univ. of Michigan, Ann Arbor, MI (United States)

    2005-11-15

    With the advent of multidetector row CT scanners, evaluation of the urothelium of the entire urinary tract with high-resolution thin sections during a single breath-hold has become a reality. Multidetector CT urography (MDCTU) is a single examination that allows evaluation of potential urinary tract calculi, renal parenchymal masses, and both benign and malignant urothelial lesions. Initial results with this new technique are encouraging. Current investigations of MDCTU focus on methods to improve opacification and distension of the upper urinary tract - the collecting systems, pelvis, and ureters. The role of abdominal compression, infusion of saline and/or furosemide, and optimal time delay of excretory phase imaging is being explored. Upper tract urothelial malignancies, including small lesions less the 5 mmin diameter, can be detected with high sensitivity. Methods to reduce radiation exposure are being explored, including split-bolus contrast injection techniques that combine nephrographic and excretory phases into a single phase. It is likely that in the near future, radiological evaluation of significant unexplained hematuria or of known or prior urothelial malignancy will consist of a single examination - MDCTU. (orig.)

  16. Hepatocellular carcinoma: prediction of blood supply from an intercostal artery with multidetector row computed tomography.

    Science.gov (United States)

    Kim, Min-Uk; Kim, Hyo-Cheol; Chung, Jin Wook; An, Sangbu; Seong, Nak Jong; Jae, Hwan Jun; Park, Jae Hyung

    2011-10-01

    To evaluate the ability of multidetector row computed tomography (CT) to detect blood supply from the intercostal artery in patients with hepatocellular carcinoma (HCC). Between January 2003 and December 2007, angiography of the intercostal artery was performed in 93 patients (76 men and 17 women, mean age 58 years) with HCC who had also undergone multidetector row CT. CT scans and digital subtraction angiograms of these patients were retrospectively reviewed by two investigators in consensus to evaluate tumor feeding vessels. Multiple logistic regression analysis was used to identify factors that predict the presence of an HCC blood supply from an intercostal artery. Tumor staining fed by an intercostal artery was noted in 65 patients (70%; 112 tumor feeding vessels) by intercostal angiography. Readers interpreted that tumor feeding vessels were evident by CT in 35 (54%) of these 65 patients with tumor staining supplied by an intercostal artery by angiography. Multiple logistic regression analysis showed that a visible tumor feeding vessel by CT (P = .003) and hepatic artery attenuation by angiography (P = .014) were significantly related to the presence of a blood supply from an intercostal artery. Visualization of a tumor feeding vessel from the intercostal artery by multidetector row CT is an important sign of parasitic supply to an HCC. Copyright © 2011 SIR. Published by Elsevier Inc. All rights reserved.

  17. 320排动态容积CT冠状动脉成像在川崎病冠状动脉瘤远期随访中应用%Application of 320-detector row dynamic volume CT angiography in follow up of coronary artery aneurysms caused by Kawasaki disease

    Institute of Scientific and Technical Information of China (English)

    刘俊; 于明华; 许开元; 向峰; 周乾潮

    2015-01-01

    目的:探讨320排动态容积CT冠状动脉成像(CTA)及经胸超声心动图(TTE)对川崎病(KD)合并冠状动脉瘤(CAA)中远期随访的应用价值。方法采用320排CTA、TTE进行中远期追踪随访8例KD合并CAA患儿。结果8例患儿平均发病年龄(41.63±22.70)月,随访时间(43.50±10.99)月。急性期TTE诊断冠状动脉巨大瘤(GCAA)3例,中小瘤5例,共累及冠状动脉16/32支(50.0%)。随访观察终点时TTE示GCAA 3例及中小瘤2例仍存在,另3例小瘤消退,仍累及冠状动脉6/32支(18.6%)。随访观察终点时320排CTA检查示累及冠状动脉7/32支(21.9%),分布部位与TTE基本一致;另发现左回旋支扩张1例,右冠状动脉(RCA)远段GCAA 1处、血栓2处、狭窄1处、钙化2处。结论KD引起的CAA可长期存在, GCAA后期可发生冠状动脉血栓、狭窄或钙化。TTE观察近中段冠脉改变敏感可靠,但对于中远段冠脉损害的观察有局限性。320排CTA能较全面地观察各支冠状动脉的病变,尤其对急性期后冠状动脉血栓,钙化及近、远端狭窄的观察敏感可靠。%ObjectiveTo assess the values of 320-detector row dynamic volume CT angiography (CTA) and transthoracic echocardiography (TTE) in follow up of coronary artery aneurysm (CAA) caused by Kawasaki disease (KD).Methods320-de-tector row CTA and TTE were applied in long-term follow-up of 8 patients with CAA caused by KD.ResultsIn 8 patients, the mean age at onset was 41.63±22.70 months and the mean follow up time was 43.50±10.99 months. In acute phase, 3 cases of giant coronary artery aneurysms (GCAA) and 5 cases of mid-small CAA were diagnosed by TTE. A total of 16/32 arteries (50%) were involved. At the end of follow-up, 3 cases of GCAA and 2 cases of mid-small CAA were still diagnosed by TTE, and small CAAs were regressed in another 3 cases. A total of 6/32 arteries (18.75%) were involved. Simultaneously at the end of follow-up, a total of 7/32 arteries (21

  18. Initial study of optimal reconstruction windows in 320-detector row CT coronary angiography%320排容积CT冠状动脉血管成像前瞻性心电门控最佳重建时相的初步研究

    Institute of Scientific and Technical Information of China (English)

    李敏; 孙钢; 彭兆辉; 李国英; 李海军; 李理; 姜相森

    2011-01-01

    Objective To investigate the optimal reconstruction windows for coronary angiography using 320-detector row dynamic volume CT (DVCT) and evaluate their effects on image quality,radiation dose and diagnostic accuracy.Methods From 77 patients [mean heart rate (70 + 13) bpm,range:46-102 bmp] were scanned with retrospective ECG-gating 320-detector row DVCT.The relationship between heart rate and optimal reconstruction windows was analyzed.From 53 patients [mean heart rate ( 75 ±11 ) bpm,range:57-114 bpm] were scanned with prospective ECG-gating 320-detector row DVCT.The effects of prospective ECG-gating on image quality,radiation dose and diagnostic accuracy were evaluated.Friedman test was performed for image quality scores in random groups.Linear regression and Spearman correlation were performed to test bivariate data.Results The proportion of systolic duration in the cardiac cycle increased significantly with higher heart rate (r =0.78,P <0.01 ).The image quality in systolic and diastolic phases were significantly influenced by heart rate ( r =0.38,0.82 ; P < 0.01 ).According to the regression analysis of image quality score in different heart rate groups,the optimal reconstruction windows were determined as followed:when heart rate was < 70 bpm,the optimal reconstruction windows should be preset at 65%-80% ; 70 to 80 bpm,70%-85% ; 81 to 90 bpm,70%-90% ; >90 bpm,35%-50%.Compared with retrospective ECG-gating,prospective ECG-gating which preset reconstruction windows according to the phases mentioned above,could decrease radiation dose [(6.1 ± 3.8 )vs (12.4 ± 7.0) mSv],without deteriorating the image quality (t =6.5,P < 0.01 ).However,in higher heart rate,the radiation dose of prospective ECG-gating DVCT was still higher ( r =0.64,P < 0.01 ).Conclusions DVCT can provide high image quality in a wide range of heart rate with prospective ECG gating.It is still recommended to control heart rate strictly since the radiation dose increases

  19. The value of multidetector row CT in evaluating left renal vein anatomy in living renal transplantation donors%多层螺旋CT在活体肾移植术前左肾静脉解剖评估中的价值

    Institute of Scientific and Technical Information of China (English)

    陶舒敏; 张喆; 吉秋; 孔祥; 张龙江

    2016-01-01

    Objective To discuss the left renal vein anatomy at multi-detector row CT and the implications for living renal transplantation.Methods The left renal vein anatomy and the branches in79 living renal transplantation donors who underwent contrast-enhanced CT angiography were analyzed retrospectively in this study. Maximum intensity projection, curve planar reformation and volume renderings were used for displaying the left renal vein anatomy. Anomalies of left renal vein and branches were recorded and classified.Results Left renal veins were all visualized on late arterial and venous phase CT images in all subjects. There were one case of circumaortic renal vein(n=1) and one case of left inferior vena cava(n=1).0 or1 adrenal vein,0 to2 lumbar veins and0 to 2 gonadal veins were found in each donor.Conclusion Among the left renal vein branches, the number of lumbar vein varied more frequently,multiple gonadal veins were detected in some subjects. Left renal vein branches should be handled carefully to avoid massive haemorrhage in left nephrectomy.%目的:探讨左肾静脉解剖变异及其属支在多层螺旋CT中的表现及其对活体肾移植的意义。方法回顾性分析79例行多层螺旋CT增强的肾移植供者左肾静脉的解剖结构及汇入左肾静脉的属支情况。采用最大密度投影、曲面重组和容积再现后处理技术,总结左肾静脉解剖变异及属支情况并分类讨论。结果多层螺旋CT动脉晚期和静脉期图像均显示左肾静脉主干,发现环主动脉左肾静脉解剖变异1例,左侧下腔静脉1例。每例供者发现肾上腺静脉0~1根,腰静脉0~2根,生殖静脉0~2根。结论左肾静脉属支中,腰静脉数目变异较多,生殖静脉肾有时会出现多根。在左肾切除术中要仔细处理静脉属支,避免大出血的发生。

  20. 64层螺旋CT脑灌注成像联合CT血管造影评价颅内外血管搭桥术后疗效%Assessment of cerebral internal and external vascular bypass graft in patients with single middle cerebral artery stenosis or occlusion by combining 64-row CT cerebral perfusion with angiography

    Institute of Scientific and Technical Information of China (English)

    陈天金; 朱栓庄; 温有信; 王耀彬; 韩向东; 白莹; 于旋

    2012-01-01

    Objective To assess the curative effect of cerebral internal and external vascular bypass graft in patients with sin -gle middle cerebral artery (MCA) stenosis or occlusion by combining 64 -row CT cerebral perfusion (CTP) with angiography ( CTA ). Methods Patients with middle cerebral artery stenosis or occlusion were recruited and underwent superficial temporal artery and mid -die cerebral artery(STA -MCA) bypass graft between March 2009 and Mar 2011. CTP and CTA examinations were performed in all patients before and after operation. The cerebral perfusion parameters were analyzed quantitatively and qualitatively . The origin, travel and anastomotic stoma of bypass grafts were evaluated by reconstructed CTA images . Results 46 patients were found with severe MCA stenosis or occlusion. The time to peak (TTP) and relative mean transit time (rMTT) images before therapy displayed the existence of perfusion delay. The relative cerebral blood flow (rCBF) and relative cerebral blood volume (rCRV) images did not change significantly. The decrease of TTP and rMTT after therapy was of statistical significance ( P 0.05). In reconstructed CTA images , 82 bridge vessels were well displayed, including double bridges in 39 patients. The accuracy of CTA examination was 96.5%. All the bypass grafts were well shown and the anastomotic stomas were unobstructed. Conclusions It is feasible to evaluate the curative effects of cerebral internal and ex — ternal vascular bypass graft by combining CTP images of cerebral perfusion after therapy with CTA images of cerebral internal and exter -nal bypass grafts.%目的 探讨64层螺旋CT脑灌注成像(CT perfusion,CTP)联合CT血管造影(CT angiography,CTA)评价单侧大脑中动脉(middle cerebral artery,MCA)重度狭窄(闭塞)颅内外血管搭桥术后疗效的可行性.方法 46例拟行颅内外血管搭桥术患者,术前、后均行CTP及CTA检查.计算脑灌注参数图,对治疗前后脑灌注参数进行定量和定性对

  1. Advances and perspectives in lung cancer imaging using multidetector row computed tomography.

    Science.gov (United States)

    Coche, Emmanuel

    2012-10-01

    The introduction of multidetector row computed tomography (CT) into clinical practice has revolutionized many aspects of the clinical work-up. Lung cancer imaging has benefited from various breakthroughs in computing technology, with advances in the field of lung cancer detection, tissue characterization, lung cancer staging and response to therapy. Our paper discusses the problems of radiation, image visualization and CT examination comparison. It also reviews the most significant advances in lung cancer imaging and highlights the emerging clinical applications that use state of the art CT technology in the field of lung cancer diagnosis and follow-up.

  2. Detection and classification of different liver lesions: Comparison of Gd-EOB-DTPA-enhanced MRI versus multiphasic spiral CT in a clinical single centre investigation

    Energy Technology Data Exchange (ETDEWEB)

    Böttcher, Joachim [Institute of Diagnostic and Interventional Radiology, SRH Clinic Gera, Str. des Friedens 122, 07548 Gera (Germany); Hansch, Andreas [Institute of Diagnostic and Interventional Radiology, Friedrich-Schiller-University, Jena University Hospital, Erlanger Allee 101, 07740 Jena (Germany); Pfeil, Alexander [Department of Internal Medicine III, Friedrich-Schiller-University, Jena University Hospital, Erlanger Allee 101, 07740 Jena (Germany); Schmidt, Peter [Institute of Diagnostic and Interventional Radiology, Friedrich-Schiller-University, Jena University Hospital, Erlanger Allee 101, 07740 Jena (Germany); Malich, Ansgar [Institute of Diagnostic Radiology, Suedharz Clinic Nordhausen, Dr. Robert-Koch-Str. 39, 99734 Nordhausen (Germany); Schneeweiss, Albrecht [Institute of Diagnostic and Interventional Radiology, Friedrich-Schiller-University, Jena University Hospital, Erlanger Allee 101, 07740 Jena (Germany); Maurer, Martin H.; Streitparth, Florian [Department of Radiology, Charité University Medicine Berlin, Campus Virchow Clinic, Augustenburger Platz 1, 13353 Berlin (Germany); Teichgräber, Ulf K. [Institute of Diagnostic and Interventional Radiology, Friedrich-Schiller-University, Jena University Hospital, Erlanger Allee 101, 07740 Jena (Germany); Renz, Diane M., E-mail: diane.renz@charite.de [Department of Radiology, Charité University Medicine Berlin, Campus Virchow Clinic, Augustenburger Platz 1, 13353 Berlin (Germany)

    2013-11-01

    Objective: To compare the diagnostic efficacy of Gd-EOB-DTPA-enhanced magnetic resonance imaging (MRI) vs. multidetector computed tomography (MDCT) for the detection and classification of focal liver lesions, differentiated also for lesion entity and size; a separate analysis of pre- and postcontrast images as well as T2-weighted MRI sequences of focal and exclusively solid lesions was integrated. Methods: Twenty-nine patients with 130 focal liver lesions underwent MDCT (64-detector-row; contrast medium iopromide; native, arterial, portalvenous, venous phase) and MRI (1.5-T; dynamic and tissue-specific phase 20 min after application of Gd-EOB-DTPA). Hepatic lesions were verified against a standard of reference (SOR). CT and MR images were independently analysed by four blinded radiologists on an ordinal 6-point-scale, determining lesion classification and diagnostic confidence. Results: Among 130 lesions, 68 were classified as malignant and 62 as benign by SOR. The detection of malignant and benign lesions differed significantly between combined and postcontrast MRI vs. MDCT; overall detection rate was 91.5% for combined MRI and 80.4% for combined MDCT (p < 0.05). Considering all four readers together, combined MDCT achieved sensitivity of 66.2%, specificity of 79.0%, and diagnostic accuracy of 72.3%; combined MRI reached superior diagnostic efficacy: sensitivity 86.8%, specificity 94.4%, accuracy 90.4% (p < 0.05). Differentiated for lesion size, in particular lesions <20 mm revealed diagnostic benefit by MRI. Postcontrast MRI also achieved higher overall sensitivity, specificity, and accuracy compared to postcontrast MDCT for focal and exclusively solid liver lesions (p < 0.05). Conclusion: Combined and postcontrast Gd-EOB-DTPA-enhanced MRI provided significantly higher overall detection rate and diagnostic accuracy, including low inter-observer variability, compared to MDCT in a single centre study.

  3. On Row Rank Equal Column Rank

    Science.gov (United States)

    Khalili, Parviz

    2009-01-01

    We will prove a well-known theorem in Linear Algebra, that is, for any "m x n" matrix the dimension of row space and column space are the same. The proof is based on the subject of "elementary matrices" and "reduced row-echelon" form of a matrix.

  4. Rasch models with exchangeable rows and columns

    DEFF Research Database (Denmark)

    Lauritzen, Steffen Lilholt

    The article studies distributions of doubly infinite binary matrices with exchangeable rows and columns which satify the further property that the probability of any $m \\times n$ submatrix is a function of the row- and column sums of that matrix. We show that any such distribution is a (unique...... of existence of measures with given marginals....

  5. Colin Rowe and ' Dynamic Equilibrium'

    Directory of Open Access Journals (Sweden)

    Pablo López Marín

    2015-05-01

    Full Text Available AbstractIn 1944 Gyorgy Kepes published what undoubtless will be his most influential text, "The language of vision". What Kepes tried to do was a guide of grammar and syntax of vision, which allows to face art as purely sensory experience or just visual, devisted of any literary , semantic or sentimental meaning.Among all the concepts that Kepes developes in his essay perhaps the most decisive one is the so called dynamic equilibrium, which is introduced in this work for fi rst time, verbalizing something that was in the air, orbiting around the entire modern plastic but far only explained in an empirical way.Colin Rowe reverberates the recent readed kepesian ideas on his own writings Transparency: Literal and Phenomenal and Neo-'Classicism' and Modern Architecture I and II, when the author tries to highlight the founding principles of the modern movement refusing the plastic  dimension of the discipline . The article will try to expose and explain this influence.

  6. Memory hierarchy using row-based compression

    Science.gov (United States)

    Loh, Gabriel H.; O'Connor, James M.

    2016-10-25

    A system includes a first memory and a device coupleable to the first memory. The device includes a second memory to cache data from the first memory. The second memory includes a plurality of rows, each row including a corresponding set of compressed data blocks of non-uniform sizes and a corresponding set of tag blocks. Each tag block represents a corresponding compressed data block of the row. The device further includes decompression logic to decompress data blocks accessed from the second memory. The device further includes compression logic to compress data blocks to be stored in the second memory.

  7. Effect of row-to-row shading on the output of flat-plate south-facing photovoltaic arrays

    Energy Technology Data Exchange (ETDEWEB)

    Goswami, D.Y.; Hassan, A.Y.; Collis, J. (North Carolina Agricultural and Technical State Univ., Greensboro, NC (USA)); Stefanakos, E.K. (University of South Florida, Tampa, FL (USA))

    1989-08-01

    When solar arrays (photovoltaic, thermal, etc.) are arranged in multiple rows of modules, all but the first row suffer reduction in (power) output, even when sufficient spacing between rows is provided. The reduction in output power occurs because the first row prevents some of the diffuse and reflected radiation from reaching the row directly behind it. This work presents estimates of the effect of shading on the amounts of solar radiation received by consecutive rows of flat-plate arrays.

  8. Is metabolic syndrome predictive of prevalence, extent, and risk of coronary artery disease beyond its components? Results from the multinational coronary CT angiography evaluation for clinical outcome: an international multicenter registry (CONFIRM.

    Directory of Open Access Journals (Sweden)

    Amir Ahmadi

    Full Text Available Although metabolic syndrome is associated with increased risk of cardiovascular disease and events, its added prognostic value beyond its components remains unknown. This study compared the prevalence, severity of coronary artery disease (CAD, and prognosis of patients with metabolic syndrome to those with individual metabolic syndrome components. The study cohort consisted of 27125 consecutive individuals who underwent ≥ 64-detector row coronary CT angiography (CCTA at 12 centers from 2003 to 2009. Metabolic syndrome was defined as per NCEP/ATP III criteria. Metabolic syndrome patients (n = 690 were matched 1:1:1 to those with 1 component (n = 690 and 2 components (n = 690 of metabolic syndrome for age, sex, smoking status, and family history of premature CAD using propensity scoring. Major adverse cardiac events (MACE were defined by a composite of myocardial infarction (MI, acute coronary syndrome, mortality and late target vessel revascularization. Patients with 1 component of metabolic syndrome manifested lower rates of obstructive 1-, 2-, and 3-vessel/left main disease compared to metabolic syndrome patients (9.4% vs 13.8%, 2.6% vs 4.5%, and 1.0% vs 2.3%, respectively; p 0.05. At 2.5 years, metabolic syndrome patients experienced a higher rate of MACE compared to patients with 1 component (4.4% vs 1.6%; p = 0.002, while no difference observed compared to individuals with 2 components (4.4% vs 3.2% p = 0.25 of metabolic syndrome. In conclusion, Metabolic syndrome patients have significantly greater prevalence, severity, and prognosis of CAD compared to patients with 1 but not 2 components of metabolic syndrome.

  9. Is Metabolic Syndrome Predictive of Prevalence, Extent, and Risk of Coronary Artery Disease beyond Its Components? Results from the Multinational Coronary CT Angiography Evaluation for Clinical Outcome: An International Multicenter Registry (CONFIRM)

    Science.gov (United States)

    Ahmadi, Amir; Leipsic, Jonathon; Feuchtner, Gudrun; Gransar, Heidi; Kalra, Dan; Heo, Ran; Achenbach, Stephan; Andreini, Daniele; Al-Mallah, Mouaz; Berman, Daniel S.; Budoff, Matthew; Cademartiri, Filippo; Callister, Tracy Q.; Chang, Hyuk-Jae; Chinnaiyan, Kavitha; Chow, Benjamin; Cury, Ricardo C.; Delago, Augustin; Gomez, Millie J.; Hadamitzky, Martin; Hausleiter, Joerg; Hindoyan, Niree; Kaufmann, Philipp A.; Kim, Yong-Jin; Lin, Fay; Maffei, Erica; Pontone, Gianluca; Raff, Gilbert L.; Shaw, Leslee J.; Villines, Todd C.; Dunning, Allison; Min, James K.

    2015-01-01

    Although metabolic syndrome is associated with increased risk of cardiovascular disease and events, its added prognostic value beyond its components remains unknown. This study compared the prevalence, severity of coronary artery disease (CAD), and prognosis of patients with metabolic syndrome to those with individual metabolic syndrome components. The study cohort consisted of 27125 consecutive individuals who underwent ≥64-detector row coronary CT angiography (CCTA) at 12 centers from 2003 to 2009. Metabolic syndrome was defined as per NCEP/ATP III criteria. Metabolic syndrome patients (n=690) were matched 1:1:1 to those with 1 component (n=690) and 2 components (n=690) of metabolic syndrome for age, sex, smoking status, and family history of premature CAD using propensity scoring. Major adverse cardiac events (MACE) were defined by a composite of myocardial infarction (MI), acute coronary syndrome, mortality and late target vessel revascularization. Patients with 1 component of metabolic syndrome manifested lower rates of obstructive 1-, 2-, and 3-vessel/left main disease compared to metabolic syndrome patients (9.4% vs 13.8%, 2.6% vs 4.5%, and 1.0% vs 2.3%, respectively; p0.05). At 2.5 years, metabolic syndrome patients experienced a higher rate of MACE compared to patients with 1 component (4.4% vs 1.6%; p=0.002), while no difference observed compared to individuals with 2 components (4.4% vs 3.2% p=0.25) of metabolic syndrome. In conclusion, Metabolic syndrome patients have significantly greater prevalence, severity, and prognosis of CAD compared to patients with 1 but not 2 components of metabolic syndrome. PMID:25734639

  10. Machine learning analysis of binaural rowing sounds

    DEFF Research Database (Denmark)

    Johard, Leonard; Ruffaldi, Emanuele; Hoffmann, Pablo F.

    2011-01-01

    Techniques for machine hearing are increasing their potentiality due to new application domains. In this work we are addressing the analysis of rowing sounds in natural context for the purpose of supporting a training system based on virtual environments. This paper presents the acquisition metho...... methodology and the evaluation of different machine learning techniques for classifying rowing-sound data. We see that a combination of principal component analysis and shallow networks perform equally well as deep architectures, while being much faster to train.......Techniques for machine hearing are increasing their potentiality due to new application domains. In this work we are addressing the analysis of rowing sounds in natural context for the purpose of supporting a training system based on virtual environments. This paper presents the acquisition...

  11. Neutron camera employing row and column summations

    Science.gov (United States)

    Clonts, Lloyd G.; Diawara, Yacouba; Donahue, Jr, Cornelius; Montcalm, Christopher A.; Riedel, Richard A.; Visscher, Theodore

    2016-06-14

    For each photomultiplier tube in an Anger camera, an R.times.S array of preamplifiers is provided to detect electrons generated within the photomultiplier tube. The outputs of the preamplifiers are digitized to measure the magnitude of the signals from each preamplifier. For each photomultiplier tube, a corresponding summation circuitry including R row summation circuits and S column summation circuits numerically add the magnitudes of the signals from preamplifiers for each row and for each column to generate histograms. For a P.times.Q array of photomultiplier tubes, P.times.Q summation circuitries generate P.times.Q row histograms including R entries and P.times.Q column histograms including S entries. The total set of histograms include P.times.Q.times.(R+S) entries, which can be analyzed by a position calculation circuit to determine the locations of events (detection of a neutron).

  12. Machine learning analysis of binaural rowing sounds

    DEFF Research Database (Denmark)

    Johard, Leonard; Ruffaldi, Emanuele; Hoffmann, Pablo F.

    2011-01-01

    Techniques for machine hearing are increasing their potentiality due to new application domains. In this work we are addressing the analysis of rowing sounds in natural context for the purpose of supporting a training system based on virtual environments. This paper presents the acquisition metho...... methodology and the evaluation of different machine learning techniques for classifying rowing-sound data. We see that a combination of principal component analysis and shallow networks perform equally well as deep architectures, while being much faster to train....

  13. Machine Learning Analysis of Binaural Rowing Sounds

    Directory of Open Access Journals (Sweden)

    Filippeschi Alessandro

    2011-12-01

    Full Text Available Techniques for machine hearing are increasing their potentiality due to new application domains. In this work we are addressing the analysis of rowing sounds in natural context for the purpose of supporting a training system based on virtual environments. This paper presents the acquisition methodology and the evaluation of different machine learning techniques for classifying rowing-sound data. We see that a combination of principal component analysis and shallow networks perform equally well as deep architectures, while being much faster to train.

  14. Thoracic CT

    Science.gov (United States)

    ... lungs; CT scan - chest Images CT scan Thyroid cancer - CT scan Pulmonary nodule, solitary - CT scan Lung mass, right upper ... Chest Injuries and Disorders CT Scans Emphysema Lung Cancer Lung Diseases Pleural Disorders Pneumonia Pulmonary Embolism Tuberculosis Browse the Encyclopedia A.D.A. ...

  15. Flexible frontiers for text division into rows

    Directory of Open Access Journals (Sweden)

    Dan L. Lacrămă

    2009-01-01

    Full Text Available This paper presents an original solution for flexible hand-written text division into rows. Unlike the standard procedure, the proposed method avoids the isolated characters extensions amputation and reduces the recognition error rate in the final stage.

  16. Can nontriggered thoracic CT be used for coronary artery calcium scoring? A phantom study

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Xueqian [Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9700RB Groningen, The Netherlands and Center for Medical Imaging – North East Netherlands, Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9700RB Groningen (Netherlands); Greuter, Marcel J. W. [Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9700RB Groningen (Netherlands); Groen, Jaap M. [Department of Radiology, Zaans Medical Center, 1500EE Zaandam (Netherlands); Bock, Geertruida H. de [Department of Epidemiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9700RB Groningen (Netherlands); Oudkerk, Matthijs [Center for Medical Imaging – North East Netherlands, Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9700RB Groningen (Netherlands); Jong, Pim A. de [Department of Radiology, University Medical Center Utrecht, University of Utrecht, 3584CX Utrecht (Netherlands); Vliegenthart, Rozemarijn [Department of Radiology, University Medical Center Groningen, University of Groningen, Hanzeplein 1, 9700RB Groningen, The Netherlands and Center for Medical Imaging – North East Netherlands, Department of Radiology, University of Groningen, University Medical Center Groningen, Hanzeplein 1, 9700RB Groningen (Netherlands)

    2013-08-15

    Purpose: Coronary artery calcium score, traditionally based on electrocardiography (ECG)-triggered computed tomography (CT), predicts cardiovascular risk. However, nontriggered CT is extensively utilized. The study-purpose is to evaluate the in vitro agreement in coronary calcium score between nontriggered thoracic CT and ECG-triggered cardiac CT.Methods: Three artificial coronary arteries containing calcifications of different densities (high, medium, and low), and sizes (large, medium, and small), were studied in a moving cardiac phantom. Two 64-detector CT systems were used. The phantom moved at 0–90 mm/s in nontriggered low-dose CT as index test, and at 0–30 mm/s in ECG-triggered CT as reference. Differences in calcium scores between nontriggered and ECG-triggered CT were analyzed by t-test and 95% confidence interval. The sensitivity to detect calcification was calculated as the percentage of positive calcium scores.Results: Overall, calcium scores in nontriggered CT were not significantly different to those in ECG-triggered CT (p > 0.05). Calcium scores in nontriggered CT were within the 95% confidence interval of calcium scores in ECG-triggered CT, except predominantly at higher velocities (≥50 mm/s) for the high-density and large-size calcifications. The sensitivity for a nonzero calcium score was 100% for large calcifications, but 46%± 11% for small calcifications in nontriggered CT.Conclusions: When performing multiple measurements, good agreement in positive calcium scores is found between nontriggered thoracic and ECG-triggered cardiac CT. Agreement decreases with increasing coronary velocity. From this phantom study, it can be concluded that a high calcium score can be detected by nontriggered CT, and thus, that nontriggered CT likely can identify individuals at high risk of cardiovascular disease. On the other hand, a zero calcium score in nontriggered CT does not reliably exclude coronary calcification.

  17. Usefulness of 320-Row Area Detector Computed Tomography for the Diagnosis of Cystic Falx Meningioma

    Directory of Open Access Journals (Sweden)

    Sadaharu Tabuchi

    2013-07-01

    Full Text Available We present a case of cystic falx meningioma. Cystic meningioma is rare and not easy to diagnose preoperatively; it is often misdiagnosed as other tumors, including glial or metastatic tumors with cystic or necrotic changes. This study showed the potential impact of 320-row computed tomography (CT on image-based diagnostic evaluation of cystic meningioma with special attention to the novel techniques of 4-dimensional CT angiography (4D-CTA and CT whole-brain perfusion (CTP. 4D-CTA showed the arterial supply feeding the tumor and late enhancement of the tumor nodule, similar to that seen in meningioma by conventional angiography. CTP showed that the tumor had a higher cerebral blood flow and cerebral blood volume and a longer mean transit time than adjacent brain tissue. These findings were consistent with meningioma and reinforced the other imaging findings, resulting in the correct preoperative diagnosis. The new techniques available for 320-row CT can potentially be used to improve differential diagnosis and preoperative assessment of cystic tumors with nodules.

  18. Row reduced representations of behaviors over finite rings

    NARCIS (Netherlands)

    Kuijper, Margreta; Pinto, Raquel; Polderman, Jan W.

    2007-01-01

    Row reduced representations of behaviors over fields posses a number of useful properties. Perhaps the most important feature is the predictable degree property. This property allows a finite parametrization of the module generated by the rows of the row reduced matrix with prior computable bounds.

  19. A spectral directional reflectance model of row crops

    NARCIS (Netherlands)

    Zhao, F.J.; Gu, X.F.; Verhoef, W.; Wang, Q.; Yu, T.; Liu, Q.; Huang, H.A.; Qin, W.; Chen, Liangfu; Zhao, H.

    2010-01-01

    A computationally efficient reflectance model for row planted canopies is developed in this paper through separating the contributions of incident direct and diffuse radiation scattered by row canopies. The row model allows calculating the reflectance spectrum in any given direction for the optical

  20. A spectral directional reflectance model of row crops

    NARCIS (Netherlands)

    Zhao, F.J.; Gu, X.F.; Verhoef, W.; Wang, Q.; Yu, T.; Liu, Q.; Huang, H.A.; Qin, W.; Chen, Liangfu; Zhao, H.

    2010-01-01

    A computationally efficient reflectance model for row planted canopies is developed in this paper through separating the contributions of incident direct and diffuse radiation scattered by row canopies. The row model allows calculating the reflectance spectrum in any given direction for the optical

  1. Interactive motion tracing for Rowing Training

    DEFF Research Database (Denmark)

    Dai, Zheng

    2011-01-01

    This paper studies motion tracking and team coordination for the training of rowers. The design research is drawn upon the division of contribution between the designers input and the user input in a design process. We built a training system that can record and show the action of a rower’s hand...... can correct the path immediately and save the corrected path for the rower to try to imitate and train. The members in a rowing team train with the same path from to coordinate and synchronize their actions for the best performance. The training system was developed through a user-centered design...... process with Danske Studenters Roklub. It was designed in iterations to provide a new experience for rowing sport training by coaching in real-time, training interactively, and perceiving directly....

  2. SVD row or column symmetric matrix

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A new architecture for row or column symmetric matrix called extended matrix is defined, and a precise correspondence of the singular values and singular vectors between the extended matrix and its original (namely, the mother matrix) is derived. As an illustration of potential, we show that, for a class of extended matrices, the singular value decomposition using the mother matrix rather than the extended matrix per se can save the CPU time and memory without loss of numerical precision.

  3. Integrated control of annual weeds by inter-row hoeing and intra-row herbicide treatment in spring oilseed rape

    Directory of Open Access Journals (Sweden)

    Nilsson, Anders

    2014-02-01

    Full Text Available The aim of this project is to develop an integrated weed control strategy against annual weeds in spring oilseed rape by means of a combined mechanical and chemical weed control which will be performed concurrently and separately. The project encompasses field experiments in which different combinations of inter-row hoeing and intra-row herbicide treatments will be evaluated and compared to conventional weed control treatments with broadcast spraying of herbicides, and experiments in which an implement for concurrent inter-row hoeing and intra-row herbicide treatment will be refined and evaluated. In 2012, an implement for intra-row spraying combined with row hoeing was developed and evaluated in two field experiments in spring oilseed rape in the southern part of Sweden. The effects of inter-row hoeing, intra row spraying, and combination of the two methods were compared with conventional broadcast spraying. Preliminary results showed that the best weed control effects were obtained with the combination of inter-row hoeing and intra-row spraying in both experiments. Regarding crop yield, the yield was significantly higher in the combined treatment in one of the experiments while no effects on the yields were obtained in the other experiment. We envisage that the inter-row hoeing and intra-row herbicide treatment will diminish the overall use of herbicides to less than one third in comparison with the more conventional chemical weed control methods, while having the same weed control effect.

  4. Diagnostic performance of combined noninvasive coronary angiography and myocardial perfusion imaging using 320 row detector computed tomography

    DEFF Research Database (Denmark)

    Vavere, Andrea L; Simon, Gregory G; George, Richard T

    2013-01-01

    Multidetector coronary computed tomography angiography (CTA) is a promising modality for widespread clinical application because of its noninvasive nature and high diagnostic accuracy as found in previous studies using 64 to 320 simultaneous detector rows. It is, however, limited in its ability...... to detect myocardial ischemia. In this article, we describe the design of the CORE320 study ("Combined coronary atherosclerosis and myocardial perfusion evaluation using 320 detector row computed tomography"). This prospective, multicenter, multinational study is unique in that it is designed to assess...... the diagnostic performance of combined 320-row CTA and myocardial CT perfusion imaging (CTP) in comparison with the combination of invasive coronary angiography and single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI). The trial is being performed at 16 medical centers located in 8...

  5. Extended abstract: Partial row projection methods

    Energy Technology Data Exchange (ETDEWEB)

    Bramley, R.; Lee, Y. [Indiana Univ., Bloomington, IN (United States)

    1996-12-31

    Accelerated row projection (RP) algorithms for solving linear systems Ax = b are a class of iterative methods which in theory converge for any nonsingular matrix. RP methods are by definition ones that require finding the orthogonal projection of vectors onto the null space of block rows of the matrix. The Kaczmarz form, considered here because it has a better spectrum for iterative methods, has an iteration matrix that is the product of such projectors. Because straightforward Kaczmarz method converges slowly for practical problems, typically an outer CG acceleration is applied. Definiteness, symmetry, or localization of the eigenvalues, of the coefficient matrix is not required. In spite of this robustness, work has generally been limited to structured systems such as block tridiagonal matrices because unlike many iterative solvers, RP methods cannot be implemented by simply supplying a matrix-vector multiplication routine. Finding the orthogonal projection of vectors onto the null space of block rows of the matrix in practice requires accessing the actual entries in the matrix. This report introduces a new partial RP algorithm which retains advantages of the RP methods.

  6. Diagnostic accuracy of noninvasive coronary angiography with 320-detector row computed tomography.

    Science.gov (United States)

    Nasis, Arthur; Leung, Michael C; Antonis, Paul R; Cameron, James D; Lehman, Sam J; Hope, Sarah A; Crossett, Marcus P; Troupis, John M; Meredith, Ian T; Seneviratne, Sujith K

    2010-11-15

    We sought to evaluate the diagnostic accuracy of noninvasive coronary angiography using 320-detector row computed tomography, which provides 16-cm craniocaudal coverage in 350 ms and can image the entire coronary tree in a single heartbeat, representing a significant advance from previous-generation scanners. We evaluated 63 consecutive patients who underwent 320-detector row computed tomography and invasive coronary angiography for the investigation of suspected coronary artery disease. Patients with known coronary artery disease were excluded. Computed tomographic (CT) studies were assessed by 2 independent observers blinded to results of invasive coronary angiography. A single observer unaware of CT results assessed invasive coronary angiographic images quantitatively. All available coronary segments were included in the analysis, regardless of size or image quality. Lesions with >50% diameter stenoses were considered significant. Mean heart rate was 63 ± 7 beats/min, with 6 patients (10%) in atrial fibrillation during image acquisition. Thirty-three patients (52%) and 70 of 973 segments (7%) had significant coronary stenoses on invasive coronary angiogram. Seventeen segments (2%) were nondiagnostic on computed tomogram and were assumed to contain significant stenoses on an "intention-to-diagnose" analysis. Sensitivity, specificity, and positive and negative predictive values of computed tomography for detecting significant stenoses were 94%, 87%, 88%, and 93%, respectively, by patient (n = 63), 89%, 95%, 82%, and 97%, respectively, by artery (n = 260), and 87%, 97%, 73%, and 99%, respectively, by segment (n = 973). In conclusion, noninvasive 320-detector row CT coronary angiography provides high diagnostic accuracy across all coronary segments, regardless of size, cardiac rhythm, or image quality.

  7. Study on the law of radiant directionality of row crops

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The style of crops planting is frequently in row-structure,the row-structure style may result in big difference among the sunlit,shaded soil surface and foliage temperatures and cause pixel component to vary in azimuth orientation,these further lead to the change of radiant directionality of row crops in the zenith and azimuth orientations.Since the row crops are often tackled as isotropic in the azimuth orientation based on continuous vegetation assumption,big errors will be brought about.In order to eliminate the errors,it is necessary to study the law of radiant directionality of the row crops.In this paper,Monte Carlo method has been employed to simulate the angular effects on radiation caused by row architecture parameters.The simulated results show that the parameters,for example,row height,row width,row interval between the neighbor rows and the leaf area index have significant influences on the radiant directionality,but the azimuth orientation ranks the first among the parameters.

  8. Multidetector row computed tomography in bowel obstruction. Part 2. Large bowel obstruction

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, R. [Department of Radiology, Glenfield Hospital, Leicester (United Kingdom)]. E-mail: rakesh.sinha@uhl-tr.nhs.uk; Verma, R. [Department of Radiology, Glenfield Hospital, Leicester (United Kingdom)

    2005-10-01

    Large bowel obstruction may present as an emergency as high-grade colonic obstruction and can result in perforation. Perforated large bowel obstruction causes faecal peritonitis, which can result in high morbidity and mortality. Multidetector row computed tomography (MDCT) has the potential of providing an accurate diagnosis of large bowel obstruction. The rapid acquisition of images within one breath-hold reduces misregistration artefacts than can occur in critically ill or uncooperative patients. The following is a review of the various causes of large bowel obstruction with emphasis on important pathogenic factors, CT appearances and the use of multiplanar reformatted images in the diagnostic workup.

  9. Cardiac imaging by means of four-detector row computed tomography and cardiac gating; Imagerie cardiaque en tomodensitometrie a quatre canaux d'acquisition et synchronisation cardiaque

    Energy Technology Data Exchange (ETDEWEB)

    Ketelslegers, E.; Coche, E.; Goffette, P.; Maldague, B.; Be, Van Beers [Clinique Universitaires UCL Saint-Luc, Bruxelles (Belgium); Gerber, B. [Clinique Universitaires UCL Saint-Luc, Dept. d' Imagerie Medicale, Bruxelles (Belgium)

    2003-09-01

    Electrocardiographically-assisted imaging is a recent development in multislice spiral computed tomography, In this article, we summarize the principles of four-detector row CT for cardiac applications. Following is an overview of the potential of this technique to evaluate the heart, the thoracic aorta, and the para-cardiac pulmonary parenchyma. Technical considerations for optimal imaging are highlighted. (authors)

  10. Myocardial perfusion 320-row multidetector computed tomography-guided treatment strategy for the clinical management of patients with recent acute-onset chest pain: Design of the CArdiac cT in the treatment of acute CHest pain (CATCH)-2 randomized controlled trial.

    Science.gov (United States)

    Sørgaard, Mathias; Linde, Jesper J; Hove, Jens D; Petersen, Jan R; Jørgensen, Tem B S; Abdulla, Jawdat; Heitmann, Merete; Kragelund, Charlotte; Hansen, Thomas Fritz; Udholm, Patricia M; Pihl, Christian; Kühl, J Tobias; Engstrøm, Thomas; Jensen, Jan Skov; Høfsten, Dan E; Kelbæk, Henning; Kofoed, Klaus F

    2016-09-01

    Patients admitted with chest pain are a diagnostic challenge because the majority does not have coronary artery disease (CAD). Assessment of CAD with coronary computed tomography angiography (CCTA) is safe, cost-effective, and accurate, albeit with a modest specificity. Stress myocardial computed tomography perfusion (CTP) has been shown to increase the specificity when added to CCTA, without lowering the sensitivity. This article describes the design of a randomized controlled trial, CATCH-2, comparing a clinical diagnostic management strategy of CCTA alone against CCTA in combination with CTP. Patients with acute-onset chest pain older than 50 years and with at least one cardiovascular risk factor for CAD are being prospectively enrolled to this study from 6 different clinical sites since October 2013. A total of 600 patients will be included. Patients are randomized 1:1 to clinical management based on CCTA or on CCTA in combination with CTP, determining the need for further testing with invasive coronary angiography including measurement of the fractional flow reserve in vessels with coronary artery lesions. Patients are scanned with a 320-row multidetector computed tomography scanner. Decisions to revascularize the patients are taken by the invasive cardiologist independently of the study allocation. The primary end point is the frequency of revascularization. Secondary end points of clinical outcome are also recorded. The CATCH-2 will determine whether CCTA in combination with CTP is diagnostically superior to CCTA alone in the management of patients with acute-onset chest pain. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. A New Hoe Blade for Inter-Row Weeding

    DEFF Research Database (Denmark)

    Green, O.; Znova, L.; Melander, Bo

    2016-01-01

    , for example uncontrollable sideward soil movement causing injurious coverage of crop plants. Based on feedbacks from researchers and practioners, a new device has been designed to overcome most of the problems associated with ‘Ducksfoot’ blades. The device consists of a stiff shank mounted on a curved VCO......New camera-based systems for automatic steering of inter-row cultivators have made it possible to conduct inter-row weeding in small inter-row spaces at reasonable work rates. This has motivated organic growers to shift from full-width weed harrowing of small grain cereals to inter-row hoeing....... The aim is mainly to improve weeding effectiveness against tall-growing and tap-rooted weed species. The ‘Ducksfoot’ hoe blade is commonly used for traditional inter-row weeding in row crops such as sugar beets and maize. This blade usually provides satisfactory weed control, if soils are not too wet...

  12. Nonparallelism of cambium cells in neighboring rows

    Directory of Open Access Journals (Sweden)

    Wiesław Włoch

    2014-02-01

    Full Text Available The periclinal walls of cambial cells in neighboring lineages (rows may not be parallel when viewed in their radial aspect. This lack of longitudinal parallelism may be so extensive that in active cambium pairs of cells from neighboring rows may be in contact only along restricted segments. This means that the initial cells, rather than farming a continuous layer, may be arranged in an irregular network pattern from which some parts project inward or outward from the layer of their mutual cantacts. The longitudinal nonparallelism of cambial cells becomes more pronounced during symplasitic radial growth. Unequal periclinal divisions counteract this, and in initial cells abscission of the parts projecting from the layer of mutual contact occurs. When the cambium passes from a period of activity to a Period of rest a continuous layer of initials is reestabhshed. This involves elongation by intrusive growth of those cells previously shortened as the result of irregular periclinal divisions. The division walls in cambial cells may be warped, that is they change their orientation along the longitudinal direction perhaps even similar to an aircraft propeller. A division wall may thus be periclinal in one part of the cell and anticlinal in another.

  13. NUMERICAL MODEL APPLICATION IN ROWING SIMULATOR DESIGN

    Directory of Open Access Journals (Sweden)

    Petr Chmátal

    2016-04-01

    Full Text Available The aim of the research was to carry out a hydraulic design of rowing/sculling and paddling simulator. Nowadays there are two main approaches in the simulator design. The first one includes a static water with no artificial movement and counts on specially cut oars to provide the same resistance in the water. The second approach, on the other hand uses pumps or similar devices to force the water to circulate but both of the designs share many problems. Such problems are affecting already built facilities and can be summarized as unrealistic feeling, unwanted turbulent flow and bad velocity profile. Therefore, the goal was to design a new rowing simulator that would provide nature-like conditions for the racers and provide an unmatched experience. In order to accomplish this challenge, it was decided to use in-depth numerical modeling to solve the hydraulic problems. The general measures for the design were taken in accordance with space availability of the simulator ́s housing. The entire research was coordinated with other stages of the construction using BIM. The detailed geometry was designed using a numerical model in Ansys Fluent and parametric auto-optimization tools which led to minimum negative hydraulic phenomena and decreased investment and operational costs due to the decreased hydraulic losses in the system.

  14. 64排螺旋 CT 及三维容积测量系统对肺叶容积的定量研究%The quantitative measurement of pulmonary lobar volume using 3-dimensional volumetric diagnosis system and 64 row MDCT

    Institute of Scientific and Technical Information of China (English)

    刘斋; 何丽; 贾立镯; 任庆云

    2016-01-01

    Objective To explore the value of 3‐dimensional volumetric diagnosis system in quantitative measurement of pulmona‐ry lobar volumetry using a 64 row MDCT .Methods Seventy‐seven adult volunteers were scanned twice on a 64 row MDCT at the end of the maximum inspiratory and maximum expiratory end respectively .On a volumetric computer‐aided diagnosis system ,the en‐tire lung was semiautomatically separated into 5 anatomy lobes including the right upper lobe ,right middle lobe ,right lower lobe ,left upper lobe ,and left lower lobe .Each lobar volume was measured .Results The lung volume of left upper lobe ,right lower lobe ,left lower lobe ,right upper lobe ,right middle lobe in male volunteers were 1 303 .90 mL and 938 .31 mL ,1 276 .90 mL and 737 .69 mL , 1 204 .47 mL and 678 .67 mL ,1 048 .49 mL and 754 .83 mL ,519 .53 mL and 407 .86 mL at the end of the inspiratory and expiratory respectively .The lung volume of left upper lobe ,right lower lobe ,left lower lobe ,right upper lobe ,right middle lobe in female volun‐teers were 915 .78 mL and 666 .23 mL ,913 .87 mL and 576 .62 mL ,822 .17 mL and 509 .30 mL ,734 .20 mL and 530 .23 mL ,389 .13 mL and 316 .70 mL at the end of the inspiratory and expiratory respectively .The values of each lobe volume between the full inspiration phase and expiration phase group showed significant difference the same sex group (P<0 .05) .The values of each lobe volume in the man group were significantly larger than those of female group in both respiratory phase (P<0 .05) .Of the D‐value in the each lobe volume in 5 anatomy lobe at full inspiration phase and expiration phase in both sex group ,both of the lower lobes were the largest , followed by the left upper lobe ,right upper lobe and right middle lobe .The D‐value in the each lobe volume at full inspiration phase and expiration phase in the man group were significantly larger than those of female group .Conclusion Three‐dimensional volumet‐ric diagnosis system

  15. Head CT scan

    Science.gov (United States)

    Brain CT; Cranial CT; CT scan - skull; CT scan - head; CT scan - orbits; CT scan - sinuses; Computed tomography - cranial; CAT scan - brain ... hold your breath for short periods. A complete scan usually take only 30 seconds to a few ...

  16. Characteristics of paraesophageal varices: A study with 64-row multidetector computed tomograghy portal venography

    Institute of Scientific and Technical Information of China (English)

    Li-Qin Zhao; Wen He; Guang Chen

    2008-01-01

    AIM:To identify the charactedsUcs of morphology,location and collateral circulation involved in paraesophageal varices (para-EV) of portal hypertension patients with 64-row multidetector computed tomograghy (MDCT).METHODS:Fifty-two of 501 patients with portal hypertensive cirrhosis accompanied with esophageal varices were selected for 64-row MDCT examination after the observation of para-EV.The CT protocol included unenhanced,arterial and portal phases with a slice thickness of 0.625 mm and a scanning field of 2 cm above the bifurcation to the lower edge of kidney.The CT portal venography (CTPV) was reformatted on AW4.3 workstation.The characteristics of origination,location,morphology and collateral circulation in para-EV were observed.RESULTS:Among the 52 cases of para-EV,50 showed the originations from the posterior branch of left gastric vein,while the others from the anterior branch.Fifty cases demonstrated their locations close to the esophagealgastric junction,and the other two cases were extended to the inferior bifurcation of the trachea.The circuitous pattern was observed in 16 cases,while reticulated pattern was seen in 36 cases.Collateral circulation identified 4 cases of single periesophageal varices (peri-EV) communication,3 cases of single hemiazygous vein,one case of single inferior vena cava,41 cases of mixed type (collateral communications of at least 2 of above mentioned types) and 3 cases of undetermined communications.Among all the cases,43 patients showed the communications between para-EV and peri-EV,while hemiazygous vein (43 cases) and inferior vena cava (5 cases) were also involved.CONCLUSION:Sixty-four-row multidetector computed tomograghy portal venography could display the location,morphology,origin,and collateral types of paraEV,which provides important and referable information for clinical management and disease prognosis.

  17. System manual for the University of Pennsylvania retrofitted solar heated Philadelphia row home (SolaRow)

    Energy Technology Data Exchange (ETDEWEB)

    Zinnes, I.; Lior, N.

    1980-05-01

    The University of Pennsylvania SolaRow house, an urban row home retrofitted for comfort and domestic hot water heating, was extensively instrumented for performance monitoring and acquisition of weather and solar radiation data. This report describes the heating and instrumentation systems, provides the details for instrumentation, piping and valve identification, and specifies the operation and maintenance of the heating and data acquisition systems. The following are included: (1) system flow diagrams; (2) valve and cable identification tables; (3) wiring diagrams; and (4) start-up, normal operation, shut-down, maintenance and trouble-shooting procedures. It thus provides the necessary technical information to permit system operation and monitoring, overall system performance analysis and optimization, and acquisition of climatological data.

  18. Improving Spectral Results Using Row-by-Row Fourier Transform of Spatial Heterodyne Raman Spectrometer Interferogram.

    Science.gov (United States)

    Barnett, Patrick D; Strange, K Alicia; Angel, S Michael

    2016-12-12

    This work describes a method of applying the Fourier transform to the two-dimensional Fizeau fringe patterns generated by the spatial heterodyne Raman spectrometer (SHRS), a dispersive interferometer, to correct the effects of certain types of optical alignment errors. In the SHRS, certain types of optical misalignments result in wavelength-dependent and wavelength-independent rotations of the fringe pattern on the detector. We describe here a simple correction technique that can be used in post-processing, by applying the Fourier transform in a row-by-row manner. This allows the user to be more forgiving of fringe alignment and allows for a reduction in the mechanical complexity of the SHRS.

  19. Rows of Dislocation Loops in Aluminium Irradiated by Aluminium Ions

    DEFF Research Database (Denmark)

    Henriksen, L.; Johansen, A.; Koch, J.

    1967-01-01

    Single-crystal aluminium specimens, irradiated with 50-keV aluminium ions, contain dislocation loops that are arranged in regular rows along <110 > directions. ©1967 The American Institute of Physics......Single-crystal aluminium specimens, irradiated with 50-keV aluminium ions, contain dislocation loops that are arranged in regular rows along directions. ©1967 The American Institute of Physics...

  20. Giant missing row reconstruction of Au on Ge(001)

    NARCIS (Netherlands)

    van Houselt, Arie; Fischer, Marinus; Poelsema, Bene; Zandvliet, Henricus J.W.

    2008-01-01

    We report on a giant missing row reconstruction emerging upon the adsorption and subsequent annealing of (sub)monolayer amounts of Au on Ge(001). The emerging microfacets are of (111) type and reminiscent of those in the well-known (2×1) missing row reconstruction of the clean (110) surfaces of the

  1. Analysis of indoor rowing motion using wearable inertial sensors

    NARCIS (Netherlands)

    Bosch, Stephan; Shoaib, Muhammad; Geerlings, Stephen; Buit, Lennart; Meratnia, Nirvana; Havinga, Paul

    2015-01-01

    In this exploratory work the motion of rowers is analyzed while rowing on a rowing machine. This is performed using inertial sensors that measure the orientation at several positions on the body. Using these measurements, this work provides a preliminary analysis of the differences between experienc

  2. Effect of BMI on Knee Joint Torques in Ergometer Rowing

    NARCIS (Netherlands)

    Roemer, Karen; Hortobagyi, Tibor; Richter, Chris; Munoz-Maldonado, Yolanda; Hamilton, Stephanie

    2013-01-01

    Although an authoritative panel recommended the use of ergometer rowing as a non-weight-bearing form of exercise for obese adults, the biomechanical characterization of ergometer rowing is strikingly absent. We examined the interaction between body mass index (BMI) relative to the lower extremity bi

  3. Effect of BMI on Knee Joint Torques in Ergometer Rowing

    NARCIS (Netherlands)

    Roemer, Karen; Hortobagyi, Tibor; Richter, Chris; Munoz-Maldonado, Yolanda; Hamilton, Stephanie

    2013-01-01

    Although an authoritative panel recommended the use of ergometer rowing as a non-weight-bearing form of exercise for obese adults, the biomechanical characterization of ergometer rowing is strikingly absent. We examined the interaction between body mass index (BMI) relative to the lower extremity bi

  4. Biomechanical determinants of elite rowing technique and performance.

    Science.gov (United States)

    Buckeridge, E M; Bull, A M J; McGregor, A H

    2015-04-01

    In rowing, the parameters of injury, performance, and technique are all interrelated and in dynamic equilibrium. Whilst rowing requires extreme physical strength and endurance, a high level of skill and technique is essential to enable an effective transfer of power through the rowing sequence. This study aimed to determine discrete aspects of rowing technique, which strongly influence foot force production and asymmetries at the foot-stretchers, as these are biomechanical parameters often associated with performance and injury risk. Twenty elite female rowers performed an incremental rowing test on an instrumented rowing ergometer, which measured force at the handle and foot-stretchers, while three-dimensional kinematic recordings of the ankle, knee, hip, and lumbar-pelvic joints were made. Multiple regression analyses identified hip kinematics as a key predictor of foot force output (R(2)  = 0.48), whereas knee and lumbar-pelvic kinematics were the main determinants in optimizing the horizontal foot force component (R(2)  = .41). Bilateral asymmetries of the foot-stretchers were also seen to significantly influence lumbar-pelvic kinematics (R(2)  = 0.43) and pelvic twisting (R(2)  = 0.32) during the rowing stroke. These results provide biomechanical evidence toward aspects of technique that can be modified to optimize force output and performance, which can be of direct benefit to coaches and athletes.

  5. Homeless alcoholic women on skid row.

    Science.gov (United States)

    Corrigan, E M; Anderson, S C

    1984-01-01

    Studies of homeless alcoholic women remain rare. Women on Skid Row in New York City were sought out at the Women's Shelter for a study of homeless women alcoholics. The findings in this study of 31 homeless alcoholic women tend to confirm an earlier study by Garrett and Bahr in most respects. A major difference relates to the population's lack of homogeneity. A life-long pattern of marginality does not exist for most of the women. All judged to be alcoholic, some lived with their families, husbands, or a male partner prior to coming to the shelter. Almost a third lived alone. Sometimes the death of someone close or other crisis precipitated homelessness. In many instances there was no apparent crisis. For a substantial group of these women there did seem to be a long-standing pattern of instability and transient living in the two years preceding their move to the shelter. Public resources invested in shelter care are much needed either for individuals whose limited resources run out or where a crisis results in the loss of safe, adequate shelter.

  6. 16-Detector row computed tomographic coronary angiography in patients undergoing evaluation for aortic valve replacement: comparison with catheter angiography

    Energy Technology Data Exchange (ETDEWEB)

    Manghat, N.E.; Morgan-Hughes, G.J.; Broadley, A.J.; Undy, M.B.; Wright, D.; Marshall, A.J.; Roobottom, C.A

    2006-09-15

    Aim: To evaluate the diagnostic accuracy of 16-detector row computed tomography (CT) in assessing haemodynamically significant coronary artery stenoses in patients under evaluation for aortic stenosis pre-aortic valve replacement. Subjects and methods: Forty consecutive patients under evaluation for severe aortic stenosis and listed for cardiac catheterization before potential aortic valve replacement underwent coronary artery calcium (CAC) scoring and retrospective electrocardiogram (ECG)-gated multi-detector row computed tomographic coronary angiography (MDCTA) using a GE Lightspeed 16-detector row CT within 1 month of invasive coronary angiography (ICA) for comparative purposes. All 13 major coronary artery segments of the American Heart Association model were evaluated for the presence of {>=}50% stenosis and compared to the reference standard. Data were analysed on a segment-by-segment basis and also in 'whole patient' terms. Results: A total of 412/450 segments from 35 patients were suitable for analysis. The overall accuracy of MDCTA for detection of segments with {>=}50% stenosis was high, with a sensitivity of 81.3%, specificity 95.0%, positive predictive value (PPV) 57.8%, and negative predictive value (NPV) 98.4%. On a 'whole-patient' basis, 100% (19/19) of patients with significant coronary disease were correctly identified and there were no false-negatives. Excluding patients with CAC >1000 from the analysis improved the accuracy of MDCTA to: sensitivity 90%, specificity 98.1%, PPV 60%, NPV 99.7%. Conclusion: Non-invasive 16-detector row MDCTA accurately excludes significant coronary disease in patients with severe aortic stenosis undergoing evaluation before aortic valve replacement and in whom ICA can therefore be avoided. Its segment-by-segment accuracy is improved further if CAC > 1000 is used as a gatekeeper to MDCTA.

  7. A Spider That Lays Its Eggs in Rows

    Directory of Open Access Journals (Sweden)

    Robert L. Edwards

    2000-01-01

    Full Text Available The small (2.5-3.0 mm, colorful metine spider, Homalometa nigritarsis Simon 1897, Family Tetragnathidae, has previously been reported from northern Mexico, Panama and the southern islands of the Lesser Antilles (Levi 1986. In the rain forest of northeastern Puerto Rico it is most frequently found with webbing on the larger outer concave surfaces of pendulous leaves. H. nigritarsis typically makes a circular, relatively flat retreat within which the female deposits two parallel rows of naked eggs. The rows are produced at intervals; as one row hatches another replaces it shortly thereafter. Evidence of up to four generations of rows has been observed. Above the retreat, and closely aligned with it, the spider builds a nearly invisible, delicate orb web, typically from edge to edge of the leaf (Fig. 1a and b. While retaining the traditional orb-web, H. nigritarsis has adopted a unique habitat and set of life history features.

  8. Effect of BMI on knee joint torques in ergometer rowing.

    Science.gov (United States)

    Roemer, Karen; Hortobagyi, Tibor; Richter, Chris; Munoz-Maldonado, Yolanda; Hamilton, Stephanie

    2013-12-01

    Although an authoritative panel recommended the use of ergometer rowing as a non-weight-bearing form of exercise for obese adults, the biomechanical characterization of ergometer rowing is strikingly absent. We examined the interaction between body mass index (BMI) relative to the lower extremity biomechanics during rowing in 10 normal weight (BMI 18-25), 10 overweight (BMI 25-30 kg·m⁻²), and 10 obese (BMI > 30 kg·m⁻²) participants. The results showed that BMI affects joint kinematics and primarily knee joint kinetics. The data revealed that high BMI leads to unfavorable knee joint torques, implying increased loads of the medial compartment in the knee joint that could be avoided by allowing more variable foot positioning on future designs of rowing ergometers.

  9. Rectal cancer staging: Multidetector-row computed tomography diagnostic accuracy in assessment of mesorectal fascia invasion.

    Science.gov (United States)

    Ippolito, Davide; Drago, Silvia Girolama; Franzesi, Cammillo Talei; Fior, Davide; Sironi, Sandro

    2016-05-28

    To assess the diagnostic accuracy of multidetector-row computed tomography (MDCT) as compared with conventional magnetic resonance imaging (MRI), in identifying mesorectal fascia (MRF) invasion in rectal cancer patients. Ninety-one patients with biopsy proven rectal adenocarcinoma referred for thoracic and abdominal CT staging were enrolled in this study. The contrast-enhanced MDCT scans were performed on a 256 row scanner (ICT, Philips) with the following acquisition parameters: tube voltage 120 KV, tube current 150-300 mAs. Imaging data were reviewed as axial and as multiplanar reconstructions (MPRs) images along the rectal tumor axis. MRI study, performed on 1.5 T with dedicated phased array multicoil, included multiplanar T2 and axial T1 sequences and diffusion weighted images (DWI). Axial and MPR CT images independently were compared to MRI and MRF involvement was determined. Diagnostic accuracy of both modalities was compared and statistically analyzed. According to MRI, the MRF was involved in 51 patients and not involved in 40 patients. DWI allowed to recognize the tumor as a focal mass with high signal intensity on high b-value images, compared with the signal of the normal adjacent rectal wall or with the lower tissue signal intensity background. The number of patients correctly staged by the native axial CT images was 71 out of 91 (41 with involved MRF; 30 with not involved MRF), while by using the MPR 80 patients were correctly staged (45 with involved MRF; 35 with not involved MRF). Local tumor staging suggested by MDCT agreed with those of MRI, obtaining for CT axial images sensitivity and specificity of 80.4% and 75%, positive predictive value (PPV) 80.4%, negative predictive value (NPV) 75% and accuracy 78%; while performing MPR the sensitivity and specificity increased to 88% and 87.5%, PPV was 90%, NPV 85.36% and accuracy 88%. MPR images showed higher diagnostic accuracy, in terms of MRF involvement, than native axial images, as compared to the

  10. Modeling of competitive distances qualified rowing and canoeing (illustrated man rowing

    Directory of Open Access Journals (Sweden)

    Samuylenko V.E.

    2013-05-01

    Full Text Available The aim of the study is to identify the best models of the race distance in rowing and canoeing. The study involved 12 highly skilled paddlers. Used heart rate monitors Polar RS800 G3, biochemical analyzer Dr. Lange LP-420. The possibility of individual simulations passage race distance. The factors that affect the distribution of forces on the distance. The optimal model of the passage of the 500 and 1000 meters. It was revealed that the distance of 200 meters has its own characteristics. The necessity of a separate simulation race distance in the non-Olympic rowing distances, length of more than 1000 meters. It is noted that in the competitive microcycle pay particular attention to the prelaunch workout consistent with the mobilization of the two leading mechanisms that ensure optimum energy supply at a distance. Recommended an increase in the volume of training loads in V (4b intensity zone in the current control to monitor the index of hemoglobin, which should not significantly decrease.

  11. QR factorization for row or column symmetric matrix

    Institute of Scientific and Technical Information of China (English)

    ZOU; Hongxing(邹红星); WANG; Dianjun(王殿军); DAI; Qionghai(戴琼海); LI; Yanda(李衍达)

    2003-01-01

    The problem of fast computing the QR factorization of row or column symmetric matrix isconsidered. We address two new algorithms based on a correspondence of Q and R matrices between the rowor column symmetric matrix and its mother matrix. Theoretical analysis and numerical evidence show that, fora class of row or column symmetric matrices, the QR factorization using the mother matrix rather than therow or column symmetric matrix per se can save dramatically the CPU time and memory without loss of anynumerical precision.

  12. Double row repair: is it worth the hassle?

    Science.gov (United States)

    Papalia, Rocco; Franceschi, Francesco; Del Buono, Angelo; Zampogna, Biagio; Maffulli, Nicola; Denaro, Vincenzo

    2011-12-01

    In the operative management of rotator cuff disease, comparable functional results have been reported after open or mini-open repair and arthroscopic fixation. Surgical repair aims to re-establish an anatomical configuration of the tendon-bone construct for restoring its mechanical performance. Single row repair is the most commonly used technique, but recently some authors have proposed to re-establish the rotator cuff footprint with 2 rows of suture anchors ("double row" repair). In regard to imaging assessment, at time zero double row repair results being more anatomic and allows for structurally sound restoration of the rotator cuff footprint. However, this does not seem to translate into superior clinical outcomes for the double row repair when evaluating all different sizes of rotator cuff tears as a whole. The scientific basis for recommending single or double row repair as preferred treatment for patients with rotator cuff tear is questionable, as minimal differences have been measured on clinical and functional rating scales.

  13. Gross efficiency during rowing is not affected by stroke rate.

    Science.gov (United States)

    Hofmijster, Mathijs J; Van Soest, Arthur J; De Koning, Jos J

    2009-05-01

    It has been suggested that the optimal stroke rate in rowing is partly determined by the stroke-rate dependence of internal power losses. This should be reflected in a stroke-rate dependency of gross efficiency (e(gross)). The purpose of this study was to investigate if e(gross) is affected by stroke rate. A second aim was to determine whether internal power losses can be estimated by the negative power output during the stroke cycle (P(negative)). Seventeen well-trained female rowers participated in this study. They rowed three trials on a modified rowing ergometer on slides at a submaximal intensity, with a respiratory exchange ratio of 1 or close to 1. Stroke rates were 28, 34, and 40 strokes per minute. The trials were fully randomized. Power transfer to the flywheel was kept constant whereas e(gross) was determined during each trial. No significant differences in e(gross) were found between conditions. This finding suggests that in rowing internal power losses are not influenced by stroke rate. Furthermore, although P(negative) increased at increasing stroke rate (P measure to estimate internal power losses. This study shows that within the range of stroke rates applied in competitive rowing, internal power losses are unrelated to rowing cycle frequency.

  14. 64-row MDCT perfusion of head and neck squamous cell carcinoma: technical feasibility and quantitative analysis of perfusion parameters

    Energy Technology Data Exchange (ETDEWEB)

    Faggioni, Lorenzo; Neri, Emanuele; Cerri, Francesca; Picano, Eugenia; Bartolozzi, Carlo [University of Pisa, Diagnostic and Interventional Radiology, Pisa (Italy); Seccia, Veronica; Muscatello, Luca; Franceschini, Stefano Sellari [University of Pisa, Division of Otorhinolaryngology, Pisa (Italy)

    2011-01-15

    To evaluate the technical feasibility of 64-row computed tomography (CT) quantitative perfusion imaging of head and neck squamous cell carcinoma (SCC). Twenty-nine patients with a total of 29 pathologically proven SCC underwent a cine-mode CT perfusion acquisition covering the lesion site. The acquisition started 10 s after intravenous injection of iodinated contrast material and lasted 50 s. On a dedicated workstation, regions of interest (ROI) were traced within the SCC, on a healthy portion of tissue (H), and on the ipsilateral sternocleidomastoid muscle (M). Blood flow (BF), blood volume (BV), mean transit time (MTT) and permeability-surface product (PS) were calculated. In SCC, BF, BV and PS were higher compared with H (p < 0.0001, p = 0.002 and p = 0.004, respectively) and M (p < 0.0001). Conversely, MTT was lower in SCC than in H (p = 0.0009) and M (p = 0.0003). All datasets were free from substantial motion artefacts and ROI misregistration phenomena. No substantial discomfort or adverse events were experienced by any of the patients. 64-row CT quantitative perfusion imaging allows head and neck SCC to be distinguished from normal tissues. (orig.)

  15. Biphasic contrast medium injection in cardiac CT: moderate versus high concentration contrast material at identical iodine flux and iodine dose.

    NARCIS (Netherlands)

    Rutten, A.; Meijs, M.F.; Vos, A.M.C.; Seidensticker, P.R.; Prokop, M.

    2010-01-01

    OBJECTIVE: To prospectively investigate the influence of contrast material concentration on enhancement in cardiac CT by using a biphasic single-injection protocol. METHODS: Sixty-four-row multidetector cardiac CT angiography was performed in 159 patients randomised to a moderate or high contrast me

  16. A Theoretical Study of Clusters: Realizing Differences between the Second-Row and the Third-Row Elements

    Institute of Scientific and Technical Information of China (English)

    XU Ya-Ge; JI Dong; SHEN Xu-Yang; WANG Xiao-Lu; LI Jia-Ming

    2006-01-01

    @@ Based on the characteristics of valence bonds and the first-principle molecular dynamics simulation we present an optimum valence bond scheme to study properties of important critical clusters with limited computational effort. The differences between the second-row and the third-row elements belonging to the same families can be understood by examining electronic structures and geometric structures even for small size clusters.

  17. Swiftness movement evaluation criteria in women's rowing

    Directory of Open Access Journals (Sweden)

    Volodymyr Bogush

    2017-08-01

    Full Text Available Purpose: to develop criteria for assessing the speed capabilities of the pace of movement, time and speed of one movement, the frequency of movements that ensure the performance of motor actions in certain conditions of a specific period of time. Material & Methods: the girls, students of the Higher School of Physical Culture and university students, specializing in rowing, various age groups and sports qualification were surveyed, all 73 athletes. According to the method of measuring the effect of the training action developed by us, we studied the speed capabilities that characterize the manifestation of the quality of swiftness. On a special stand athletes made hand movements from the target to target. In the first period of the test, with a duration of 15 seconds, the athletes were to gain maximum speed; In the second period, with a duration of 60 s, it was necessary to maintain the achieved speed – distance velocity was investigated; in the third period – 15 seconds, speed endurance was determined – the athletes were supposed to perform the motor task with the maximum speed. The pace, time and speed of single movement, the frequency of movements were determined, and sensorimotor responses to sound and light stimuli were studied in modeling the conditions of training and competitive activity. Result: formation and improvement of motor abilities in specific age ranges is caused by high rates of development of morphological and functional indicators in sensitive periods. Obtained results characterize the individual psycho-physiological characteristics of the athlete's body in the context of modeling sports activities, show a different reaction in the observed age groups, a different level of sports qualification, which makes it possible to make adjustments in improving the speed abilities and effectively manage the training process. Conclusion: based on a comparative analysis of the studies that carried out, criteria were developed for

  18. Don't Rock the Boat : How Antiphase Crew Coordination Affects Rowing

    NARCIS (Netherlands)

    de Brouwer, Anouk J.; de Poel, Harjo J.; Hofmijster, Mathijs J.

    2013-01-01

    It is generally accepted that crew rowing requires perfect synchronization between the movements of the rowers. However, a long-standing and somewhat counterintuitive idea is that out-of-phase crew rowing might have benefits over in-phase (i.e., synchronous) rowing. In synchronous rowing, 5 to 6% of

  19. Don't Rock the Boat : How Antiphase Crew Coordination Affects Rowing

    NARCIS (Netherlands)

    de Brouwer, Anouk J.; de Poel, Harjo J.; Hofmijster, Mathijs J.

    2013-01-01

    It is generally accepted that crew rowing requires perfect synchronization between the movements of the rowers. However, a long-standing and somewhat counterintuitive idea is that out-of-phase crew rowing might have benefits over in-phase (i.e., synchronous) rowing. In synchronous rowing, 5 to 6% of

  20. Right heart on multidetector CT

    Science.gov (United States)

    Gopalan, D

    2011-01-01

    Right ventricular function plays an integral role in the pathogenesis and outcome of many cardiovascular diseases. Imaging the right ventricle has long been a challenge because of its complex geometry. In recent years there has been a tremendous expansion in multidetector row CT (MDCT) and its cardiac applications. By judicious modification of contrast medium protocol, it is possible to achieve good opacification of the right-sided cardiac chambers, thereby paving the way for exploring the overshadowed right heart. This article will describe the key features of right heart anatomy, review MDCT acquisition techniques, elaborate the various morphological and functional information that can be obtained, and illustrate some important clinical conditions associated with an abnormal right heart. PMID:22723537

  1. CT Enterography

    Science.gov (United States)

    ... You may also be asked to remove hearing aids and removable dental work. Women will be asked to remove bras ... kind, unlike MRI. No radiation remains in a patient's body after a CT ... side effects. Risks There is always a slight chance of cancer ...

  2. Detection of Dental Pathologies in Routine Paranasal CT Scans: A Retrospective Study.

    Science.gov (United States)

    Bulbul, Erdogan; Yanik, Bahar; Demirpolat, Gulen

    2017-07-01

    Multidetector Computed Tomography (MDCT) is a widespread method for evaluating paranasal sinuses and nasal cavity in daily practice. The maxillary teeth are in field of view in a paranasal sinus CT scan and it is possible to detect dental pathologies with CT. To determine the incidence of maxillary teeth pathologies in routine paranasal sinus CT scans. A retrospective study was conducted. Consecutive 395 paranasal sinus CT scans were evaluated. All CT images were obtained with a 64 detector-CT. Patients with previous facial trauma, operation, invasive tumors and repeated exams were excluded. Detected findings were classified as "tooth loss, dental restorations or procedures and dental pathologies (carious lesions, dental developmental anomalies, periapical lesions and periodontal diseases). The proportion of findings was reported as simple percentiles. Three hundred and eighty-four CT scans were included in the study. Dental restorations or procedures were determined in 129 (33.5%) patients. A total of 34 (8.8%) patients had normal teeth count and morphology. A total of 264 (64.3%) patients had at least one tooth loss. A total of 195 (51%) patients had at least one or more dental pathology. Number of dental carious lesions, dental developmental anomalies, periapical lesions and periodontal disease were 104 (27.0%), 78 (14.3%), 46 (11.9%), 44 (11.4%), respectively. Dental pathologies were encountered in more than half of the patients. Detecting dental pathologies may prevent tooth loss and improve oral health. The radiologist should keep in mind dental pathologies while evaluating paranasal sinus CT in daily practice.

  3. Plant population and row spacing on biomass sorghum yield performance

    Directory of Open Access Journals (Sweden)

    Andre May

    2015-01-01

    Full Text Available ABSTRACT: Biomass sorghum is one of the most promising crops for the production of electricity through the burning in high-pressure boilers, due to its high calorific value, high yield, seed propagation, short cycle, and to the possibility of full mechanization of its agricultural processes. However, there is still a lack of information about its cultural practices. To this end, this research aimed to evaluate the influence of row spacing and plant population on the yield performance of biomass sorghum. The experimental design was a randomized block, in factorial scheme of 4 x 4, with four row spacings (0.5, 0.7, 0.9 and 1.1m, and four plant populations (80,000; 100,000; 120,000 and 140,000 plants ha-1, with three replications. The characteristics evaluated were: plant height, stem diameter, number of leaves, number of tillers per plant, fresh weight per plant and biomass. Total biomass yield was greatly influenced by the row spacing, showing a sharp reduction when row spacing increased, in the two years of study, changing from 180.27 to 114.42t ha-1 in the 2012/13 crop year, and from 146.50 to 102.56t ha-1 in the 2013/14 crop year, for 0.5 and 1.1m between rows, respectively. The lowest yields observed in the second year of the study were due to unfavorable weather conditions in the period.

  4. Developmental venous anomalies: appearance on whole-brain CT digital subtraction angiography and CT perfusion

    Energy Technology Data Exchange (ETDEWEB)

    Hanson, Eric H. [Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); University of Nevada Las Vegas, Department of Health Physics and Diagnostic Sciences, 4505 Maryland Parkway, Box 453037, Las Vegas, NV (United States); Amigenics, Inc, Las Vegas, NV (United States); Roach, Cayce J. [Advanced Medical Imaging and Genetics (Amigenics), Las Vegas, NV (United States); University of Nevada Las Vegas, School of Life Sciences, Las Vegas, NV (United States); Ringdahl, Erik N. [University of Nevada Las Vegas, Department of Psychology, Las Vegas, NV (United States); Wynn, Brad L. [Family Medicine Spokane, Spokane, WA (United States); DeChancie, Sean M.; Mann, Nathan D. [Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); Diamond, Alan S. [CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); Orrison, William W. [Touro University Nevada College of Osteopathic Medicine, Henderson, NV (United States); University of Nevada Las Vegas, Department of Health Physics and Diagnostic Sciences, 4505 Maryland Parkway, Box 453037, Las Vegas, NV (United States); CHW Nevada Imaging Company, Nevada Imaging Centers, Spring Valley, Las Vegas, NV (United States); University of Nevada School of Medicine, Department of Medical Education, Reno, NV (United States)

    2011-05-15

    Developmental venous anomalies (DVA) consist of dilated intramedullary veins that converge into a large collecting vein. The appearance of these anomalies was evaluated on whole-brain computed tomography (CT) digital subtraction angiography (DSA) and CT perfusion (CTP) studies. CT data sets of ten anonymized patients were retrospectively analyzed. Five patients had evidence of DVA and five age- and sex-matched controls were without known neurovascular abnormalities. CT angiograms, CT arterial-venous views, 4-D CT DSA and CTP maps were acquired on a dynamic volume imaging protocol on a 320-detector row CT scanner. Whole-brain CTP parameters were evaluated for cerebral blood flow (CBF), cerebral blood volume (CBV), time to peak (TTP), mean transit time (MTT), and delay. DSA was utilized to visualize DVA anatomy. Radiation dose was recorded from the scanner console. Increased CTP values were present in the DVA relative to the unaffected contralateral hemisphere of 48%, 32%, and 26%; and for the control group with matched hemispheric comparisons of 2%, -10%, and 9% for CBF, CBV, and MTT, respectively. Average effective radiation dose was 4.4 mSv. Whole-brain DSA and CTP imaging can demonstrate a characteristic appearance of altered DVA hemodynamic parameters and capture the anomalies in superior cortices of the cerebrum and the cerebellum. Future research may identify the rare subsets of patients at increased risk of adverse outcomes secondary to the altered hemodynamics to facilitate tailored imaging surveillance and application of appropriate preventive therapeutic measures. (orig.)

  5. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... a stroke, especially with a new technique called Perfusion CT. brain tumors. enlarged brain cavities (ventricles) in ... X-Ray and CT Exams Blood Clots CT Perfusion of the Head CT Angiography (CTA) Stroke Brain ...

  6. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... Professions Site Index A-Z Computed Tomography (CT) - Head Computed tomography (CT) of the head uses special ... the Head? What is CT Scanning of the Head? Computed tomography, more commonly known as a CT ...

  7. Nutrition and Supplements for Elite Open-Weight Rowing.

    Science.gov (United States)

    Boegman, Susan; Dziedzic, Christine E

    2016-01-01

    Competitive rowing events are raced over 2,000 m requiring athletes to have highly developed aerobic and anaerobic systems. Elite rowers therefore undertake training sessions focused on lactate tolerance, strength and power as well as aerobic and anaerobic capacity development, that can amount to a 24-h training week. The training stimuli and consequent metabolic demands of each session in a rowing training program differ depending on type, length, and intensity. Nutrition guidelines for endurance- and power-based sports should be drawn upon; however, individualized and flexible nutrition plans are critical to successfully meet the daily, weekly, and cyclic nutrient requirements of a rower. This review will provide an overview of key nutritional strategies to optimize training and enhance adaptation, and briefly discuss supplement strategies that may support health and enhance performance in elite rowing.

  8. Hydrodynamic characteristics of three rows of vertical slotted wall breakwaters

    Science.gov (United States)

    Alsaydalani, Majed O.; Saif, Mohammed A. N.; Helal, Medhat M.

    2017-09-01

    In this study, we examine the hydrodynamic characteristics of three rows of vertical slotted wall breakwaters in which the front and middle walls are permeable and partially immersed in a water channel of constant depth, whereas the third wall is impermeable. The wave-structure interaction and flow behavior of this type of breakwater arrangement are complicated and must be analyzed before breakwaters can be appropriately designed. To study the hydrodynamic breakwater performance, we developed a mathematical model based on the eigenfunction expansion method and a least squares technique for predicting wave interaction with three rows of vertical slotted wall breakwaters. We theoretically examined the wave transmission, reflection, energy loss, wave runup, and wave force under normal regular waves. Comparisons with experimental measurements show that the mathematical model results adequately reproduce most of the important features. The results of this investigation provide a better understanding of the hydrodynamic performance of triple-row vertical slotted wall breakwaters.

  9. Clontarf to Curtin: Row AHEAD and Tertiary Affinity

    Directory of Open Access Journals (Sweden)

    Cameron Thorn

    2015-10-01

    Full Text Available In Western Australia, and around the world, rowing is a sport that is often associated with elite private schools and tertiary institutions (Cambridge University Boat Club, 2013; Yale Athletics, 2010; Oxford University Boat Club, 2015; Melbourne University Boat Club, 2015. Events like the Boat Race, an annual rowing event for the top Oxford and Cambridge University crews, and the Henley Royal Regatta, held on the Thames River since 1839, serve to reinforce the elitist history of the sport. In a more local context, rowing in Western Australia is predominantly facilitated by a number of high-fee-paying secondary schools running their own competitions for male and female students throughout the year. Despite the majority of these schools supporting Indigenous students via full academic and boarding scholarships, it is estimated that a maximum of 20 Indigenous students have participated in rowing in some way over the past 10 years. On a national level, Indigenous participation is estimated to be about 0.01% (L. Callier, pers. comm. May 8, 2014. The program designers believed it was worth noting that Indigenous higher education students make up around 2% of the national higher education student body (Australian Bureau of Statistics, 2011. The designers believed that these participation rates were worth highlighting, given the historical development of the sport of rowing, and could add value to the delivery of the program and narrative of the participant journey, resulting from an increase in engagement. A program was designed to engage Indigenous students in the sport of rowing, and support them through an aspiration and awareness-raising curriculum.

  10. Self-dual interval orders and row-Fishburn matrices

    CERN Document Server

    Yan, Sherry H F

    2011-01-01

    Recently, Jel\\'{i}nek derived that the number of self-dual interval orders of reduced size $n$ is twice the number of row-Fishburn matrices of size $n$ by using generating functions. In this paper, we present a bijective proof of this relation by establishing a bijection between two variations of upper-triangular matrices of nonnegative integers. Using the bijection, we provide a combinatorial proof of the refined relations between self-dual Fishburn matrices and row-Fishburn matrices in answer to a problem proposed by Jel\\'{i}nek.

  11. Evaluation of multimodal feedback effects on improving rowing competencies

    Directory of Open Access Journals (Sweden)

    Korman Maria

    2011-12-01

    Full Text Available This study focused on the selection and preliminary evaluation of different types of modal and information feedback in virtual environment to facilitate acquisition and transfer of a complex motor-cognitive skill of rowing. Specifically, we addressed the effectiveness of immediate information feedback provided visually as compared to sensory haptic feedback on the improvement in hands kinematics and changes in cognitive load during the course of learning the basic rowing technique. Several pilot experiments described in this report lead to the evaluation and optimization of the training protocol, to enhance facilitatory effects of adding visual and haptic feedback during training.

  12. Low-dose triple-rule-out using 320-row-detector volume MDCT--less contrast medium and lower radiation exposure.

    Science.gov (United States)

    Durmus, Tahir; Rogalla, Patrik; Lembcke, Alexander; Mühler, Matthias R; Hamm, Bernd; Hein, Patrick A

    2011-07-01

    To investigate image quality of triple-rule-out (TRO) computed tomography (CT) using a 320-row-detector CT system with substantially reduced contrast medium volume at 100 kV. Forty-six consecutive patients with noncritical, acute chest pain underwent 320-row-detector CT using a two-step TRO protocol consisting of a non-spiral, non-gated chest CT acquisition (150 mA) followed by a non-spiral, electrocardiography-gated cardiac acquisition (200-500 mA based on body mass index (BMI)). Data were acquired using a biphasic injection protocol with a total iodinated contrast medium volume of 60 ml (370 mg/ml). Vessel attenuation and effective doses were recorded. Image quality was scored independently by two readers. Mean attenuation was 584 ± 114 Hounsfield units (HU) in the ascending aorta, 335 ± 63HU in the aortic arch, 658 ± 136HU in the pulmonary trunk, and 521 ± 97HU and 549 ± 102HU in the right and left coronary artery, respectively. In all but one patient, attenuation and image quality allowed accurate visualization of the pulmonary arteries, thoracic aorta, and coronary arteries in a single examination. Ninety-six percent of all coronary artery segments were rated diagnostic. Radiation exposure ranged between 2.0 and 3.3 mSv. Using 320-row-detector CT the investigated low-dose TRO protocol resulted in excellent opacification and image quality with substantial reduction of contrast medium volume compared to recently published TRO protocols.

  13. Feasibility of coronary calcium and stent image subtraction using 320-detector row CT angiography

    DEFF Research Database (Denmark)

    Fuchs, Andreas; Kühl, J Tobias; Chen, Marcus Y;

    2015-01-01

    . We defined target segments on CCTAconv as motion-free coronary segments with calcification or stent and low reader confidence. The effect of CCTAsub was assessed. No approval from the ethics committee was required according to Danish law. RESULTS: A total of 76 target segments were identified....... The use of coronary calcium image subtraction improved the reader confidence in 66% of these segments. In target segments, specificity (86% vs 65%; P

  14. Low-dose multidetector-row CT-angiography of abdominal aortic aneurysm after endovascular repair

    Energy Technology Data Exchange (ETDEWEB)

    Iezzi, R., E-mail: iezzir@virgilio.it [Department of Bioimaging and Radiological Sciences, Institute of Radiology, ' A. Gemelli' Hospital - Catholic University, L.go A Gemelli 8, 00168 Rome (Italy); Department of Clinical Science and Bioimaging, Section of Radiology, University ' G. D' Annunzio' , Chieti (Italy); Cotroneo, A.R.; Giammarino, A. [Department of Clinical Science and Bioimaging, Section of Radiology, University ' G. D' Annunzio' , Chieti (Italy); Spigonardo, F. [Department of Vascular Surgery, University ' G. D' Annunzio' , Chieti (Italy); Storto, M.L. [Department of Clinical Science and Bioimaging, Section of Radiology, University ' G. D' Annunzio' , Chieti (Italy)

    2011-07-15

    Purpose: To investigate the possibility of reducing radiation dose exposure while maintaining image quality using multidetector computed tomography angiography (MDCTA) with high-concentration contrast media in patients undergoing follow-up after endovascular aortic repair (EVAR) to treat abdominal aortic aneurysm. Materials and methods: In this prospective, single center, intra-individual study, patients underwent two consecutive MDCTA scans 6 months apart, one with a standard acquisition protocol (130 mAs/120 kV) and 120 mL of iomeprol 300, and one using a low dose protocol (100 mAs/80 kV) and 90 mL of iomeprol 400. Images acquired during the arterial phase of contrast enhancement were evaluated both qualitatively and quantitatively for image noise and intraluminal contrast enhancement. Results: Thirty adult patients were prospectively enrolled. Statistically significantly higher attenuation values were measured in the low-dose acquisition protocol compared to the standard protocol, from the suprarenal abdominal aorta to the common femoral artery (p < 0.0001; all vascular segments). Qualitatively, image quality was judged significantly (p = 0.0002) better with the standard protocol than with the low-dose protocol. However, no significant differences were found between the two protocols in terms of contrast-to-noise ratio (CNR) (13.63 {+-} 6.97 vs. 11.48 {+-} 8.13; p = 0.1058). An overall dose reduction of up to 74% was observed for the low-dose protocol compared with the standard protocol. Conclusion: In repeat follow-up examinations of patients undergoing EVAR for abdominal aortic aneurysm, a low-dose radiation exposure acquisition protocol provides substantially reduced radiation exposure while maintaining a constant CNR and good image quality.

  15. Illinois Occupational Skill Standards: Row Crop Production Cluster.

    Science.gov (United States)

    Illinois Occupational Skill Standards and Credentialing Council, Carbondale.

    This document, which is intended as a guide for work force preparation program providers, details the Illinois occupational skill standards for programs preparing students for employment in occupations in the row crop production cluster. The document begins with a brief overview of the Illinois perspective on occupational skill standards and…

  16. Strip tillage for single and twin-row peanut

    Science.gov (United States)

    Soil degradation and rising production costs have prompted grower interest in conservation tillage with high residue cover crops for peanut (Arachis hypogaea L.). The objective was to evaluate single and twin-row peanut production across three different strip tillage implements with and without a c...

  17. Cooperative catalysis with first-row late transition metals

    NARCIS (Netherlands)

    J.I. van der Vlugt

    2012-01-01

    Cooperative catalysis with first-row transition metals holds much promise for future developments regarding sustainable, selective transformations, including e.g. alkenes, dienes and a variety of small molecules such as CO2, N2 and water. This non-exhaustive analysis of the current state-of-the-art

  18. Reduced dosages of atrazine and narrow rows can provide ...

    African Journals Online (AJOL)

    hope&shola

    2010-11-08

    Nov 8, 2010 ... weeding to keep the crop weed-free and avert yield losses (Mashingaidze and ..... (1998) who reported little benefit in maize to narrow row spacings as a .... analysis of crop rotation effects on weed seed banks. Am. J. Bot. 82:.

  19. A CMOS image sensor with row and column profiling means

    NARCIS (Netherlands)

    Xie, N.; Theuwissen, A.J.P.; Wang, X.; Leijtens, J.A.P.; Hakkesteegt, H.; Jansen, H.

    2008-01-01

    This paper describes the implementation and firstmeasurement results of a new way that obtains row and column profile data from a CMOS Image Sensor, which is developed for a micro-Digital Sun Sensor (μDSS).The basic profiling action is achieved by the pixels with p-type MOS transistors which realize

  20. Rowing Crew Coordination Dynamics at Increasing Stroke Rates

    NARCIS (Netherlands)

    Cuijpers, Laura S.; Zaal, Frank T. J. M.; de Poel, Harjo J.

    2015-01-01

    In rowing, perfect synchronisation is important for optimal performance of a crew. Remarkably, a recent study on ergometers demonstrated that antiphase crew coordination might be mechanically more efficient by reducing the power lost to within-cycle velocity fluctuations of the boat. However, couple

  1. PET/CT: underlying physics, instrumentation, and advances.

    Science.gov (United States)

    Torres Espallardo, I

    2017-01-12

    Since it was first introduced, the main goal of PET/CT has been to provide both PET and CT images with high clinical quality and to present them to radiologists and specialists in nuclear medicine as a fused, perfectly aligned image. The use of fused PET and CT images quickly became routine in clinical practice, showing the great potential of these hybrid scanners. Thanks to this success, manufacturers have gone beyond considering CT as a mere attenuation corrector for PET, concentrating instead on design high performance PET and CT scanners with more interesting features. Since the first commercial PET/CT scanner became available in 2001, both the PET component and the CT component have improved immensely. In the case of PET, faster scintillation crystals with high stopping power such as LYSO crystals have enabled more sensitive devices to be built, making it possible to reduce the number of undesired coincidence events and to use time of flight (TOF) techniques. All these advances have improved lesion detection, especially in situations with very noisy backgrounds. Iterative reconstruction methods, together with the corrections carried out during the reconstruction and the use of the point-spread function, have improved image quality. In parallel, CT instrumentation has also improved significantly, and 64- and 128-row detectors have been incorporated into the most modern PET/CT scanners. This makes it possible to obtain high quality diagnostic anatomic images in a few seconds that both enable the correction of PET attenuation and provide information for diagnosis. Furthermore, nowadays nearly all PET/CT scanners have a system that modulates the dose of radiation that the patient is exposed to in the CT study in function of the region scanned. This article reviews the underlying physics of PET and CT imaging separately, describes the changes in the instrumentation and standard protocols in a combined PET/CT system, and finally points out the most important

  2. Design, Construction and Evaluation of a Row Crop Thinning Machine

    Directory of Open Access Journals (Sweden)

    M Gol Mohammadi

    2014-04-01

    Full Text Available Equipment availability is necessary in the development of Agriculture mechanization. Crop thinning is one of the most important stages in row crop production which is laborious and costly. The objective of this project is design and construction of a row crop thinning machine. Four main system units are plant sensors, ground sensors, control and thinning platforms. In this machine the unwanted plants on the rows are randomly removed by employing a pneumatically system. A blade on a vertical arm with pendulum motion removes the plant from the rows. The machine control system consists of an arm and a blade which is activated by a double acting cylinder and equipped with a relay and a timer. The pneumatic cylinder is controlled via a solenoid valve. Laboratory tests were conducted to validate the machine performance. Some other preliminary tests also were performed for optimization of parameters such as cinematic index and cutting length of blades. The laboratory tests (totally 9 tests were performed with a constant forward speed and three levels of plant density, using artificial plants. The data were analyzed using SPSS software. The results show that satisfactory performance of the machine is achieved when the plant density is moderate i.e. the thinning performance reduces with higher plant distance in the row. The other effective variable on machine performance is the adjustment of sensor sensitivity, which is used to distinguish between week and strong plants. In general the machine performance is sensitive to plant shape and morphology, plant distribution pattern in the field, growing stage of the plants, time of thinning and the effectiveness of previous weeding operations

  3. Entrance surface dose measurements using a small OSL dosimeter with a computed tomography scanner having 320 rows of detectors.

    Science.gov (United States)

    Takegami, Kazuki; Hayashi, Hiroaki; Yamada, Kenji; Mihara, Yoshiki; Kimoto, Natsumi; Kanazawa, Yuki; Higashino, Kousaku; Yamashita, Kazuta; Hayashi, Fumio; Okazaki, Tohru; Hashizume, Takuya; Kobayashi, Ikuo

    2017-03-01

    Entrance surface dose (ESD) measurements are important in X-ray computed tomography (CT) for examination, but in clinical settings it is difficult to measure ESDs because of a lack of suitable dosimeters. We focus on the capability of a small optically stimulated luminescence (OSL) dosimeter. The aim of this study is to propose a practical method for using an OSL dosimeter to measure the ESD when performing a CT examination. The small OSL dosimeter has an outer width of 10 mm; it is assumed that a partial dose may be measured because the slice thickness and helical pitch can be set to various values. To verify our method, we used a CT scanner having 320 rows of detectors and checked the consistencies of the ESDs measured using OSL dosimeters by comparing them with those measured using Gafchromic™ films. The films were calibrated using an ionization chamber on the basis of half-value layer estimation. On the other hand, the OSL dosimeter was appropriately calibrated using a practical calibration curve previously proposed by our group. The ESDs measured using the OSL dosimeters were in good agreement with the reference ESDs from the Gafchromic™ films. Using these data, we also estimated the uncertainty of ESDs measured with small OSL dosimeters. We concluded that a small OSL dosimeter can be considered suitable for measuring the ESD with an uncertainty of 30 % during CT examinations in which pitch factors below 1.000 are applied.

  4. Optimization of Inter-Row Spacing and Nitrogen Rate for the Application of Vision Guided Inter-Row weeding in Organic Spring Cereals

    DEFF Research Database (Denmark)

    Melander, Bo; Green, O.; Znova, L.

    2016-01-01

    tall-growing and tap-rooted weed species have been major drawbacks. New camera technology capable of detecting crop rows makes it possible to employ selective weed control in spring cereals. Normally cereals are grown at 12.5 cm row spacing in Northern Europe but even a moderate extension of the row...... spacing can make enough room for implementing automatically steered inter-row hoeing. Experiences from practice have shown that camera-based steering systems can guide a hoe blade accurately in a 20-25 cm wide inter-row space. The steering systems have also improved work rates by increasing implement...... not been optimized to the usage of inter-row cultivation. Intra-row weeds, i.e. those growing in the crop lines, are not controlled and increasing the row spacing to 25 cm or more may cause a yield penalty. The aim of this study was to investigate the interaction between inter-row cultivation, inter-row...

  5. Diagnostic performance of combined noninvasive coronary angiography and myocardial perfusion imaging using 320 row detector computed tomography: design and implementation of the CORE320 multicenter, multinational diagnostic study.

    Science.gov (United States)

    Vavere, Andrea L; Simon, Gregory G; George, Richard T; Rochitte, Carlos E; Arai, Andrew E; Miller, Julie M; Di Carli, Marcello; Arbab-Zadeh, Armin; Zadeh, Armin A; Dewey, Marc; Niinuma, Hiroyuki; Laham, Roger; Rybicki, Frank J; Schuijf, Joanne D; Paul, Narinder; Hoe, John; Kuribyashi, Sachio; Sakuma, Hajime; Nomura, Cesar; Yaw, Tan Swee; Kofoed, Klaus F; Yoshioka, Kunihiro; Clouse, Melvin E; Brinker, Jeffrey; Cox, Christopher; Lima, Joao A C

    2011-01-01

    Multidetector coronary computed tomography angiography (CTA) is a promising modality for widespread clinical application because of its noninvasive nature and high diagnostic accuracy as found in previous studies using 64 to 320 simultaneous detector rows. It is, however, limited in its ability to detect myocardial ischemia. In this article, we describe the design of the CORE320 study ("Combined coronary atherosclerosis and myocardial perfusion evaluation using 320 detector row computed tomography"). This prospective, multicenter, multinational study is unique in that it is designed to assess the diagnostic performance of combined 320-row CTA and myocardial CT perfusion imaging (CTP) in comparison with the combination of invasive coronary angiography and single-photon emission computed tomography myocardial perfusion imaging (SPECT-MPI). The trial is being performed at 16 medical centers located in 8 countries worldwide. CT has the potential to assess both anatomy and physiology in a single imaging session. The co-primary aim of the CORE320 study is to define the per-patient diagnostic accuracy of the combination of coronary CTA and myocardial CTP to detect physiologically significant coronary artery disease compared with (1) the combination of conventional coronary angiography and SPECT-MPI and (2) conventional coronary angiography alone. If successful, the technology could revolutionize the management of patients with symptomatic CAD.

  6. Simulation of design-unbiased point-to-particle sampling compared to alternatives on plantation rows

    Science.gov (United States)

    Thomas B. Lynch; David Hamlin; Mark J. Ducey

    2016-01-01

    Total quantities of tree attributes can be estimated in plantations by sampling on plantation rows using several methods. At random sample points on a row, either fixed row lengths or variable row lengths with a fixed number of sample trees can be assessed. Ratio of means or mean of ratios estimators can be developed for the fixed number of trees option but are not...

  7. Using the 64-slice Perfusion CT to Evaluate the Oxygen Tension(pO2) in the Rabbit VX2 Tumor Model: An Experimental Study%64层灌注CT评价兔VX2体部肿瘤模型氧分压的实验研究

    Institute of Scientific and Technical Information of China (English)

    孙昌进; 肖明勇; 阴俊; 于金明; 郞锦义; 王光辉; 李超; 李涛; 罗云秀; 吕海波; 张德康; 李彦; 黄建鸣

    2013-01-01

    Objective: To investigate the role of the 64-slice perfusion CT in the evaluation of the oxygen tension ( pO2 ) in the rabbit VX2 tumor model. Methods: Forty-five rabbit VX2 brain tumor model established successfully were examined with 64-detector row CT. Tumor specimens were assessed for the oxygen tension ( pO2 ) , perfusion, blood volume ( BV) , peak enhancement intensity ( PEI) and time to peak (TTP) , and Pearson correlation coefficients were conducted to represent the relationships between the perfusion parameters and pO2 of the tumor. pO2was measured by oxygen-sensitive electrodes guided by perfusion CT images. Results: Mean values for perfusion,BV,PEI, TTP and pO2 of the 45 tumors were 27. 102 ± 26. 723ml/min, 22. 1 96 ± 13. 680ml/100g,43. 456 ±28.73 HU, 38.823 ±14.759 sec,and 15.981 ± 14.815mmHg, respectively. BV,PEI, TTP were not significant correlated with pO2 (r =0.271, 0. 253 、- 0. 18 , P > 0. 05 ) , whereas positively correlation was found between perfusion with pO2 ( r = 0. 673, P = 0. 00 ). Conclusion: The perfusion value from 64-slice spiral CT perfusion imaging might to have ability to evaluate the tumor pO2%目的:利用64层灌注CT评价兔VX2肿瘤模型氧分压并与氧微电极法对照.方法:对45只成功建模兔VX2脑瘤模型行灌注CT检查.测量脑瘤兴趣区灌注值(perfusion)、血容量(blood volume,BV)、达峰时间(time to peak TTP)、最大峰值(peak enhancement intensity,PEI).结果与该兴趣区氧微电极法测得氧分压(PO2)对照.结果:45例成功建模兔VX2脑瘤兴趣区灌注值范围为1.3 ml/min~127.0 ml/min,平均为27.102 ml/min±26.723 ml/min;BV为1.2 ml/100g~53.1ml/100g,平均为22.196 ml/100g±13.680ml/100g,PEI为8.7 HU~124.6HU,平均为43.456 HU±28.73 HU; TTP为8.2 sec~62.5 sec,平均为38.823 sec±14.759 sec;对应区域PO2为0.14 mmHg~46.70mmHg,平均为15.981 mmHg±14.815mmHg.灌注值与对应区域PO2相关系数为0.673,有统计学意义(P=0.00).BV

  8. Effects of stroke resistance on rowing economy in club rowers post-season.

    Science.gov (United States)

    Kane, D A; Mackenzie, S J; Jensen, R L; Watts, P B

    2013-02-01

    In the sport of rowing, increasing the impulse applied to the oar handle during the stroke can result in greater boat velocities; this may be facilitated by increasing the surface area of the oar blade and/or increasing the length of the oars. The purpose of this study was to compare the effects of different rowing resistances on the physiological response to rowing. 5 male and 7 female club rowers completed progressive, incremental exercise tests on an air-braked rowing ergometer, using either low (LO; 100) or high (HI; 150) resistance (values are according to the adjustable "drag factor" setting on the ergometer). Expired air, blood lactate concentration, heart rate, rowing cadence, and ergometer power output were monitored during the tests. LO rowing elicited significantly greater cadences (P<0.01) and heart rates (P<0.05), whereas rowing economy (J · L O(2) equivalents(-1)) was significantly greater during HI rowing (P<0.05). These results suggest that economically, rowing with a greater resistance may be advantageous for performance. Moreover, biomechanical analysis of ergometer rowing support the notion that the impulse generated during the stroke increases positively as a function of rowing resistance. We conclude that an aerobic advantage associated with greater resistance parallels the empirical trend toward larger oar blades in competitive rowing. This may be explained by a greater stroke impulse at the higher resistance.

  9. Row-Sum of a Class of M-Bonomial Coefficients

    Science.gov (United States)

    Asiru, Muniru A.

    2011-01-01

    Formulae for row-sum of M-bonomial coefficients [image omitted] where G is an mth g-gonal number is developed from a study of the ratio between consecutive terms of the sequence of row-sum. The result generalizes the formula for row-sum of binomial coefficients: [image omitted].

  10. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... a relatively short time, especially when compared to magnetic resonance imaging (MRI). CT scanning is painless, noninvasive and accurate. A ... CT is less sensitive to patient movement than MRI. CT can be performed if you have an ...

  11. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... CT is less sensitive to patient movement than MRI. CT can be performed if you have an implanted medical device of any kind, unlike MRI. A diagnosis determined by CT scanning may eliminate ...

  12. Abdominal and Pelvic CT

    Medline Plus

    Full Text Available ... CT Scanning of the Abdomen and Pelvis? What is CT Scanning of the Abdomen/Pelvis? Computed tomography, ... the body being studied. top of page How is the CT scan performed? The technologist begins by ...

  13. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... additional view capabilities. Modern CT scanners are so fast that they can scan through large sections of ... after the procedure? CT exams are generally painless, fast and easy. With multidetector CT, the amount of ...

  14. Abdominal and Pelvic CT

    Medline Plus

    Full Text Available ... Professions Site Index A-Z Computed Tomography (CT) - Abdomen and Pelvis Computed tomography (CT) of the abdomen ... and Pelvis? What is CT Scanning of the Abdomen/Pelvis? Computed tomography, more commonly known as a ...

  15. Abdominal and Pelvic CT

    Science.gov (United States)

    ... Professions Site Index A-Z Computed Tomography (CT) - Abdomen and Pelvis Computed tomography (CT) of the abdomen ... and Pelvis? What is CT Scanning of the Abdomen/Pelvis? Computed tomography, more commonly known as a ...

  16. Generalized Row-Action Methods for Tomographic Imaging

    DEFF Research Database (Denmark)

    Andersen, Martin Skovgaard; Hansen, Per Christian

    2014-01-01

    initial convergence which is desirable in applications where a low-accuracy solution is acceptable. In this paper, we propose relaxed variants of a class of incremental proximal gradient methods, and these variants generalize many existing row-action methods for tomographic imaging. Moreover, they allow......Row-action methods play an important role in tomographic image reconstruction. Many such methods can be viewed as incremental gradient methods for minimizing a sum of a large number of convex functions, and despite their relatively poor global rate of convergence, these methods often exhibit fast...... us to derive new incremental algorithms for tomographic imaging that incorporate different types of prior information via regularization. We demonstrate the efficacy of the approach with some numerical examples....

  17. Optimizing ROW Vegetation Management for Wildlife, Farmers, and Taxpayers

    OpenAIRE

    Cotter, Steve

    2017-01-01

    Invasive plants cause ecological and economic damage to Indiana’s agricultural and natural areas. Best management practices for right-ofways (ROWs) can not only minimize the damage to both sectors but also provide real benefits on both fronts. Through the establishment of corridors of habitat for Indiana’s colorful families of native insects, especially bees and butterflies, pollinators can continue to play their increasingly important role in the landscape. Join us for a discussion.

  18. On development of CFD platform for blade rows

    OpenAIRE

    Nishizawa, Toshio; Nozaki, Osamu; Nakamura, Takashi; Fukuda, Masahiro; Kato, Akifumi; Sukemura, Shuniti; Kawasaki, Takuji; 西澤 敏雄; 野崎 理; 中村 孝; 福田 正大; 加藤 昭史; 助村 俊一; 川崎 琢治

    2000-01-01

    The present paper shows a CFD (Computational Fluid Dynamics) platform for blade rows, which realize efficient engineering environment for aerodynamic designers of turbomachine for aircraft engines, ships and electric power plants. The platform consists of PCs, WSs (Workstations) and supercomputers on network. It provides graphic user interfaces on these computers to control the CFD programs, so that the designers can operate very easily their tasks such as generating the computational grids, ...

  19. Row, Row, Row Your Boat...

    Institute of Scientific and Technical Information of China (English)

    PHILIP JONES

    2010-01-01

    @@ My afternoon plans to go dragon boat racing on Houhai Lake in downtown Beijing could have started better. Cycling across town, a pedal snapped off my bicycle as I was aggressively building up speed across a Second Ring Road junction.

  20. Optimization of Rowing Specific Training by Studying the Stages Evaluation

    Directory of Open Access Journals (Sweden)

    Sanda T Urichianu

    2011-01-01

    Full Text Available Problem statement: We intended to analyze and systematize the most valuable ways through which is achieved the optimization in rowing training by the evaluation of control norms, trials and tests during some stages of the training plan. We consider that the sports performances can become better and better thanks to a continuous improvement of the working methodology during the main periods of training. Approach: The study was conducted over a period of 10 months (December 1, 2009-September 1, 2010 within the Sports Clubs, Juniors Department, men, of Falticeni and Iasi and it was made during the pre-competitive and competitive training period. The subjects of our research represent a group of 24 athletes from the two clubs: CS Falticeni and CS Iasi, out of which only 9 subjects have been able to obtained significant results. The study emphasizes the performances achieved during the control tests on ergometer rowing machines and on water (6000 and 2000 m events. Results: The study results confirmed that there is a significant relationship of the control tests results, erg and the competitive performance. The athletes’ performance is determined by the level of physical training specific to the rowing. Conclusion: To further enhance the performances, one should not neglect the study of any side which could help coaches and methods specialists in their work with the athletes.

  1. Colin Rowe: Space as well-composed illusion

    Directory of Open Access Journals (Sweden)

    Christoph Schnoor

    2011-12-01

    Full Text Available Architectural historian Colin Rowe, although well known for his intriguing analytical writings on modern architecture, rarely examined architectural space as a scholarly subject-matter. Historians examining Rowe’s writings rarely refer to the issue of space, either. Anthony Vidler, Werner Oechslin, Alexander Caragonne and others have examined Rowe’s investigations into urban space, his analyses of formal principles in architecture, or his critical stance towards the myths of modernism, but have not singled out architectural space as subject matter. Nevertheless, this paper argues that Rowe is indeed one of the few post-war historians writing in the English language to have conveyed analyses of architectural space, particularly in the volume The Mathematics of the Ideal Villa (1976. The paper examines how Rowe understood architectural space as relevant only when not seen as ‘pure’ but ‘contaminated’ with ambiguity and active character: notions of flatness versus depth and horizontal versus vertical, as well as the overlapping of conflicting scales or whole structural or spatial systems are central for Rowe’s reading of architectural space, which is also always infused with an idea of movement. Further, the paper traces influences of Rowe’s approach beyond the obvious influence by Rudolf Wittkower to Heinrich Wölfflin’s style and method, partially conveyed through the translation of Sigfried Giedion’s writings.

  2. Vision-GPS Fusion for Guidance of an Autonomous Vehicle in Row Crops

    DEFF Research Database (Denmark)

    Bak, Thomas

    2001-01-01

    at a constant rate ignoring the spatial variability in weed, soil, and crop. Sensing with a guided vehicle allow cost effective mapping of field variability and inputs may be adjusted accordingly. Essential to such a vehicle is real-time localization. GPS allow precise absolute sensing but it is not practical...... to guide the vehicle relative to the crop rows on an absolute coordinate. A row guidance sensor is therefore included to sense the position relative to the rows. The vehicle path in the field is re-planned online in order to allow for crop row irregularities sensed by the row sensor. The path generation...

  3. Imaging of cochlear implant electrode array with flat-detector CT and conventional multislice CT: comparison of image quality and radiation dose.

    Science.gov (United States)

    Struffert, Tobias; Hertel, Victoria; Kyriakou, Yannis; Krause, Jens; Engelhorn, Tobias; Schick, Bernhard; Iro, Heinrich; Hornung, Joachim; Doerfler, Arnd

    2010-04-01

    Cochlear implantation assessment is possible using commercially available standard flat-detector computed tomography (FD-CT) protocols. Image quality is superior to multislice CT (MSCT). The radiation dose of FD-CT is lower in comparison with MSCT standard protocols and may therefore overcome the limitations of MSCT in the evaluation of cochlear implants. FD-CT offers higher spatial resolution than MSCT. Our objective was to compare the image quality of FD-CT to conventional MSCT in the visualization of a cochlear implant electrode array with respect to radiation exposure. An isolated temporal bone specimen was scanned using a commercially available FD-CT system and a 4 and 64 row MSCT scanner. Different scanning protocols were used. Image quality was assessed by four independent readers using a scoring system with different criteria describing delineation of the cochlea and the electrode array, image noise and spatial resolution. Radiation dose was measured using the CT dose index (CTDI) and a 16 cm acrylic phantom. Image quality was rated superior for FD-CT for all criteria by all readers. Single electrode contacts were only visible in FD-CT and assessment of implant position was improved by FD-CT. The radiation dose of FD-CT was half that of MSCT standard protocols.

  4. Correlation of 64 row MDCT, echocardiography and cardiac catheterization angiography in assessment of pulmonary arterial anatomy in children with cyanotic congenital heart disease

    Energy Technology Data Exchange (ETDEWEB)

    Chandrashekhar, Guruprasadh, E-mail: cguruprasadh@gmail.com [Departments of Radiodiagnosis and Imaging, Post Graduate Institute of Medical Education and Research, Sector-12, Chandigarh 160012 (India); Sodhi, Kushaljit Singh, E-mail: sodhiks@gmail.com [Departments of Radiodiagnosis and Imaging, Post Graduate Institute of Medical Education and Research, Sector-12, Chandigarh 160012 (India); Saxena, Akshay Kumar, E-mail: fatakshay@yahoo.com [Departments of Radiodiagnosis and Imaging, Post Graduate Institute of Medical Education and Research, Sector-12, Chandigarh 160012 (India); Rohit, Manoj Kumar, E-mail: rohitmanoj@gmail.com [Department of Pediatric Cardiology, Post Graduate Institute of Medical Education and Research, Sector-12, Chandigarh 160012 (India); Khandelwal, Niranjan, E-mail: khandelwaln@hotmail.com [Departments of Radiodiagnosis and Imaging, Post Graduate Institute of Medical Education and Research, Sector-12, Chandigarh 160012 (India)

    2012-12-15

    Objective: To study the correlation of low-dose 64-row multi-detector computed tomography (MDCT) with echocardiography and cardiac catheterization angiography (CCA) in the assessment of pulmonary arterial anatomy in children with cyanotic congenital heart disease (CCHD). Materials and methods: This prospective study included 105 children (74 males, 31 females) with CCHD, in the age group of 2 months to 20 years, who underwent 64-row MDCT examination (low-dose CT protocol), echocardiography and CCA for the assessment of pulmonary arteries, including visualization, presence of confluence, stenosis and collaterals. Statistical analysis was performed using the non-parametric statistical analysis test to evaluate the concordance or discordance between echocardiography, MDCT and CCA. Results: 64-row MDCT detected significantly more main and branch pulmonary arteries, patent pulmonary confluences, and more cases of pulmonary artery stenosis. CCA detected more major aorto-pulmonary collaterals than MDCT, whereas echocardiography failed to identify these major aorto-pulmonary collaterals. The effective CT radiation dose to patients less than 2 years of age was in the range of 0.7–2.5 mSv, where as the dose in patients more than 2 years of age ranged from that of 2.1 to 4.2 mSv, which is much less than the radiation dose reported in cardiac catheterization angiography. Conclusion: In cases where cardiac MRI cannot be performed, or is not sufficiently informative, low-dose 64-row MDCT correlates well with CCA and can provide adequate information about pulmonary arterial anatomy in children with cyanotic congenital heart disease, and can replace invasive cardiac catheterization angiography with markedly reduced radiation dosage to the patient.

  5. Vision-GPS Fusion for Guidance of an Autonomous Vehicle in Row Crops

    DEFF Research Database (Denmark)

    Bak, Thomas

    2001-01-01

    This paper presents a real-time localization system for an autonomous vehicle passing through 0.25 m wide crop rows at 6 km/h. Localization is achieved by fusion of mea-surements from a row guidance sensor and a GPS receiver. Conventional agricultural practice applies inputs such as herbicide...... at a constant rate ignoring the spatial variability in weed, soil, and crop. Sensing with a guided vehicle allow cost effective mapping of field variability and inputs may be adjusted accordingly. Essential to such a vehicle is real-time localization. GPS allow precise absolute sensing but it is not practical...... to guide the vehicle relative to the crop rows on an absolute coordinate. A row guidance sensor is therefore included to sense the position relative to the rows. The vehicle path in the field is re-planned online in order to allow for crop row irregularities sensed by the row sensor. The path generation...

  6. Accuracy of multidetector row computed tomography for the diagnosis of acute bowel ischemia in a non-selected study population

    Energy Technology Data Exchange (ETDEWEB)

    Wiesner, Walter [University Hospital Basel, Institute of Diagnostic Radiology, Basel (Switzerland); Clinic Stephanshorn, Medical Radiology Center, St. Gallen (Switzerland); Hauser, Andreas; Steinbrich, Wolfgang [University Hospital Basel, Institute of Diagnostic Radiology, Basel (Switzerland)

    2004-12-01

    The diagnostic accuracy of multidetector row computed tomography for the prospective diagnosis of acute bowel ischemia in the daily clinical routine was analyzed. Two hundred ninety-one consecutive patients with an acute or subacute abdomen, examined by MDCT over a time period of 5 months, were included in the study. All original CT diagnoses made during the daily routine by radiological generalists were compared to the final diagnoses made by using all available medical information from endoscopies, surgical interventions, autopsies and follow-up. Finally, all CT examinations of patients with an initial CT diagnosis or a final diagnosis of bowel ischemia were reread by a radiologist specialized in abdominal imaging in order to analyze the CT findings and the reasons for initially false negative or false positive CT readings. Twenty-four patients out of 291 (8.2%) had acute bowel ischemia. The age of affected patients ranged from 50 to 94 years (mean age: 75.7 years). Eleven patients were male, and 13 female. Reasons for acute bowel ischemia were: arterio-occlusive (n=11), non-occlusive (n=5), strangulation (n=2), over-distension (n=3) and radiation (n=3). The prospective sensitivity, specificity, PPV and NPV of MDCT for the diagnosis of acute bowel ischemia in the daily routine were 79.17, 98.51, 90.48 and 98.15%. MDCT reaches a similarly high sensitivity in diagnosing acute bowel as angiography. Furthermore, it has the advantage of being helpful in most of its clinical differential diagnoses and of being less invasive with the consecutive possibility of being used earlier in the diagnostic process with all the resulting positive effects on the patients prognosis. Therefore, nowadays MDCT should probably be used as the first step imaging modality of choice in patients with suspected acute bowel ischemia. (orig.)

  7. Flat-panel volume CT: fundamental principles, technology, and applications.

    Science.gov (United States)

    Gupta, Rajiv; Cheung, Arnold C; Bartling, Soenke H; Lisauskas, Jennifer; Grasruck, Michael; Leidecker, Christianne; Schmidt, Bernhard; Flohr, Thomas; Brady, Thomas J

    2008-01-01

    Flat-panel volume computed tomography (CT) systems have an innovative design that allows coverage of a large volume per rotation, fluoroscopic and dynamic imaging, and high spatial resolution that permits visualization of complex human anatomy such as fine temporal bone structures and trabecular bone architecture. In simple terms, flat-panel volume CT scanners can be thought of as conventional multidetector CT scanners in which the detector rows have been replaced by an area detector. The flat-panel detector has wide z-axis coverage that enables imaging of entire organs in one axial acquisition. Its fluoroscopic and angiographic capabilities are useful for intraoperative and vascular applications. Furthermore, the high-volume coverage and continuous rotation of the detector may enable depiction of dynamic processes such as coronary blood flow and whole-brain perfusion. Other applications in which flat-panel volume CT may play a role include small-animal imaging, nondestructive testing in animal survival surgeries, and tissue-engineering experiments. Such versatility has led some to predict that flat-panel volume CT will gain importance in interventional and intraoperative applications, especially in specialties such as cardiac imaging, interventional neuroradiology, orthopedics, and otolaryngology. However, the contrast resolution of flat-panel volume CT is slightly inferior to that of multidetector CT, a higher radiation dose is needed to achieve a comparable signal-to-noise ratio, and a slower scintillator results in a longer scanning time.

  8. Imaging features of solid pseudopapillary tumor of the pancreas on multi-detector row computed tomography

    Institute of Scientific and Technical Information of China (English)

    Deng-Bin Wang; Qing-Bing Wang; Wei-Min Chai; Ke-Min Chen; Xia-Xing Deng

    2009-01-01

    AIM:To retrospectively analyze the imaging features of solid-pseudopapillary tumors (SPTs) of the pancreas on multi-detector row computed tomography (MDCT) and define the imaging findings suggestive of malignant potential.METHODS: A total of 24 consecutive cases with surgically and pathologically confirmed SPTs of the pancreas underwent preoperative abdominal MDCT studies in our hospital. All axial CT images, CT angiographic images, and coronally and sagittally reformed images were obtained. The images were retrospectively reviewed at interactive picture archiving and communication system workstations. RESULTS: Of the 24 cases of SPTs, 11 cases (45.8%) occurred in the pancreatic head and seven (29.1%) in the tail. Eighteen were pathologically diagnosed as benign and six as malignant. MDCT diagnosis of SPTs was well correlated with the surgical and pathological results (Kappa = 0.6, P < 0.05). The size of SPTs ranged from 3 to 15 cm (mean, 5.8 cm). When the size of the tumor was greater than 6 cm (including 6cm), the possibilities of vascular (8 vs 1) and capsular invasion (9 vs 0) increased significantly ( P < 0.05). Two pathologically benign cases with vascular invasion and disrupted capsule on MDCT presented with local recurrence and hepatic metastases during follow-up about 1 year after the resection of the primary tumors.CONCLUSION: Vascular and capsular invasion with superimposed spread into the adjacent pancreatic parenchyma and nearby structures in SPTs of the pancreas can be accurately revealed by MDCTpreoperatively. These imaging findings are predictive of the malignant potential associated with the aggressive behavior of the tumor, even in the pathologically benign cases.

  9. Mode of inheritance and combining abilities for kernel row number, kernel number per row and grain yield in maize (Zea mays L.)

    NARCIS (Netherlands)

    Bocanski, J.; Sreckov, Z.; Nastasic, A.; Ivanovic, M.; Djalovic, I.; Vukosavljev, M.

    2010-01-01

    Bocanski J., Z. Sreckov, A. Nastasic, M. Ivanovic, I.Djalovic and M. Vukosavljev (2010): Mode of inheritance and combining abilities for kernel row number, kernel number per row and grain yield in maize (Zea mays L.) - Genetika, Vol 42, No. 1, 169- 176. Utilization of heterosis requires the study of

  10. Mode of inheritance and combining abilities for kernel row number, kernel number per row and grain yield in maize (Zea mays L.)

    NARCIS (Netherlands)

    Bocanski, J.; Sreckov, Z.; Nastasic, A.; Ivanovic, M.; Djalovic, I.; Vukosavljev, M.

    2010-01-01

    Bocanski J., Z. Sreckov, A. Nastasic, M. Ivanovic, I.Djalovic and M. Vukosavljev (2010): Mode of inheritance and combining abilities for kernel row number, kernel number per row and grain yield in maize (Zea mays L.) - Genetika, Vol 42, No. 1, 169- 176. Utilization of heterosis requires the study of

  11. Brain perfusion CT for acute stroke using a 256-slice CT: improvement of diagnostic information by large volume coverage

    Energy Technology Data Exchange (ETDEWEB)

    Dorn, F. [Technical University, Department of Radiology, Klinikum rechts der Isar, Munich (Germany); Institut fuer Radiologie, Klinikum rechts der Isar der Technischen Universitaet Muenchen, Muenchen (Germany); Muenzel, D.; Meier, R.; Rummeny, E.J.; Huber, A. [Technical University, Department of Radiology, Klinikum rechts der Isar, Munich (Germany); Poppert, H. [Technical University, Department of Neurology, Klinikum rechts der Isar, Munich (Germany)

    2011-09-15

    To compare a 256-slice CT with a simulated standard CT for brain CT perfusion (CTP). CTP was obtained in 51 patients using a 256-slice CT (128 detector rows, flying z-focus, 8-cm detector width, 80 kV, 120mAs, 20 measurements, 1 CT image/2.5 s). Signal-to-noise ratios (SNR) were compared in grey and white matter. Perfusion maps were evaluated for cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) in hypoperfused areas and corresponding contralateral regions. Two reconstructed 10-mm slices for simulation of a standard CT (SDCT) were compared with the complete data sets (large-volume CT, LVCT). Adequate image quality was achieved in 50/51 cases. SNR were significantly different in grey and white matter. A perfusion deficit was present in 27 data sets. Differences between the hypoperfusions and the control regions were significant for MTT and CBF, but not for CBV. Three lesions were missed by SDCT but detected by LVCT; 24 lesions were covered incompletely by SDCT, and 6 by LVCT. 21 lesions were detected completely by LVCT, but none by SDCT. CTP imaging of the brain using an increased detector width can detect additional ischaemic lesions and cover most ischaemic lesions completely. (orig.)

  12. [Weighted-averaging multi-planar reconstruction method for multi-detector row computed tomography].

    Science.gov (United States)

    Aizawa, Mitsuhiro; Nishikawa, Keiichi; Sasaki, Keita; Kobayashi, Norio; Yama, Mitsuru; Sano, Tsukasa; Murakami, Shin-ichi

    2012-01-01

    Development of multi-detector row computed tomography (MDCT) has enabled three-dimensions (3D) scanning with minute voxels. Minute voxels improve spatial resolution of CT images. At the same time, however, they increase image noise. Multi-planar reconstruction (MPR) is one of effective 3D-image processing techniques. The conventional MPR technique can adjust slice thickness of MPR images. When a thick slice is used, the image noise is decreased. In this case, however, spatial resolution is deteriorated. In order to deal with this trade-off problem, we have developed the weighted-averaging multi-planar reconstruction (W-MPR) technique to control the balance between the spatial resolution and noise. The weighted-average is determined by the Gaussian-type weighting function. In this study, we compared the performance of W-MPR with that of conventional simple-addition-averaging MPR. As a result, we could confirm that W-MPR can decrease the image noise without significant deterioration of spatial resolution. W-MPR can adjust freely the weight for each slice by changing the shape of the weighting function. Therefore, W-MPR can allow us to select a proper balance of spatial resolution and noise and at the same time produce suitable MPR images for observation of targeted anatomical structures.

  13. Assessment of regional left ventricular function with multidetector-row computed tomography versus magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Fischbach, Roman; Juergens, Kai U.; Ozgun, Murat; Maintz, David; Seifarth, Harald; Heindel, Walter [University of Muenster, Department of Clinical Radiology, Muenster (Germany); Grude, Matthias; Wichter, Thomas [University of Muenster, Department of Cardiology and Angiology, Muenster (Germany)

    2007-04-15

    This study compares quantitative and qualitative information on global and regional left ventricular (LV) function obtained with multidetector-row computed tomography (MDCT) with that obtained with magnetic resonance imaging (MRI) in patients with a high prevalence of LV wall motion abnormalities. Thirty patients (19 male, 63.7{+-}15.1 years) with myocardial infarction (n=12), coronary artery disease (n=9), arrhythmogenic right ventricular cardiomyopathy (n=6), and dilation cardiomyopathy (n=3) were included. Segmental LV wall motion (LV-WM) was assessed using a 4-point scale. Wall thickness measurements were calculated in diastolic and systolic short axis images. Two hundred and fifty-two out of 266 (94.7%) normal and 189 out of 214 (88.3%) segments with decreased wall motion were correctly identified by MDCT, yielding a sensitivity of 88% and specificity of 95% for identification of wall motion abnormalities. LV-WM scores were identical in 86.7% of 480 segments ({kappa}=0.809). MDCT had a tendency to underestimate the degree of wall motion impairment. Interobserver agreement was lower in MDCT (66.5%) than in MRI (89.1%; p<0.01). Normokinetic segments are reliably identified with MDCT. Sensitivity for detection and accurate classification of LV wall motion abnormalities need to be improved. Better temporal resolution of the CT system seems to be the most important factor for enhancing MDCT performance. (orig.)

  14. Commercial software upgrades may significantly alter Perfusion CT parameter values in colorectal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Goh, Vicky [Mount Vernon Hospital, Paul Strickland Scanner Centre, Northwood, Middlesex (United Kingdom); Shastry, Manu; Endozo, Raymondo; Groves, Ashley M. [University College Hospital, Institute of Nuclear Medicine, London (United Kingdom); Engledow, Alec; Peck, Jacqui [University College Hospital, Department of Surgery, London (United Kingdom); Reston, Jonathan; Wellsted, David M. [University of Hertfordshire, Centre for Lifespan and Chronic Illness Research (CLiCIR), Hatfield (United Kingdom); Rodriguez-Justo, Manuel [University College Hospital, Department of Histopathology, London (United Kingdom); Taylor, Stuart A.; Halligan, Steve [University College Hospital, Specialist Radiology, London (United Kingdom)

    2011-04-15

    To determine how commercial software platform upgrades impact on derived parameters for colorectal cancer. Following ethical approval, 30 patients with suspected colorectal cancer underwent Perfusion CT using integrated 64 detector PET/CT before surgery. Analysis was performed using software based on modified distributed parameter analysis (Perfusion software version 4; Perfusion 4.0), then repeated using the previous version (Perfusion software version 3; Perfusion 3.0). Tumour blood flow (BF), blood volume (BV), mean transit time (MTT) and permeability surface area product (PS) were determined for identical regions-of-interest. Slice-by-slice and 'whole tumour' variance was assessed by Bland-Altman analysis. Mean BF, BV and PS was 20.4%, 59.5%, and 106% higher, and MTT 14.3% shorter for Perfusion 4.0 than Perfusion 3.0. The mean difference (95% limits of agreement) were +13.5 (-44.9 to 72.0), +2.61 (-0.06 to 5.28), -1.23 (-6.83 to 4.36), and +14.2 (-4.43 to 32.8) for BF, BV, MTT and PS respectively. Within subject coefficient of variation was 36.6%, 38.0%, 27.4% and 60.6% for BF, BV, MTT and PS respectively indicating moderate to poor agreement. Software version upgrades of the same software platform may result in significantly different parameter values, requiring adjustments for cross-version comparison. (orig.)

  15. Ambichronous historiography: Colin Rowe and the teaching of architectural history

    Directory of Open Access Journals (Sweden)

    Braden Engel

    2016-06-01

    Full Text Available Ianus Architectus is the Latin combination of the Architect with the ancient Roman god of beginnings and ends, pasts and futures, Janus. It represents the dual act of both seeing past-and-future (Janus’ two faces, and producing (architecture, simultaneously. Twentieth century American schools of architecture received an influx of European art historians who transformed the way students viewed buildings of the past and their own design work. Trained in architectural design and art history, Colin Rowe was the most active participant in the interface between histories and practices of architecture. Rowe’s practice was ambichronous, as he attempted to engage with history while liberating innovation in design.

  16. Quality Function Deployment For Row House Construction In Real Estate

    Directory of Open Access Journals (Sweden)

    Sukhlal Mujalda

    2015-06-01

    Full Text Available Abstract House construction for real state is the current demand to satisfy the different categories of customer. Various techniques are available to satisfy the customer demand like QFD. Using the QFD house of quality modal we were able to understand the fundamental customer quality and care requirement within the real estate construction. This paper represent a simple case using QFD on the design phase of a real estate construction project as a tool of improvement for feature of middle class row house unit.

  17. [Study of renal veins by multidetector-row computed tomography scans].

    Science.gov (United States)

    Bouali, O; Mouttalib, S; Labarre, D; Munzer, C; Lopez, R; Lauwers, F; Moscovici, J

    2014-12-01

    To determine the prevalence of renal vein variants. To investigate the distribution of renal veins. We retrospectively reviewed spiral computed tomography (CT) scans of the abdomen performed during a two-month period. The same protocol was used for all CT scans: same multidetector-row CT scanner (Siemens(®)), 1 to 2-mm section thickness, injection of intravenous iomeprol. The study group included 121 patients, aged 21.7 to 93.4 years (mean age 60.9 ± 15.4 years). The sex ratio was 2/1, with 80 men and 41 women. Seventy-three percent of the study group (88 patients) had no variants of the renal veins. Indeed almost 40% (48 patients) had one artery and one vein on each side, with typical course, and 33% (40 patients) had course and/or number variants of the renal arteries. Variants of the right renal vein consisted in multiple veins in 20.6% (25 cases). We detected no case of multiple left renal veins, but we described variations of its course in 9.1% (11 cases): 5 cases of retroaortic left renal vein (4.1%) and 6 cases of circumaortic left renal vein (5%). Three of these 11 patients had an associated double right renal vein. The probability to have a right renal vein variant was significantly higher than a left one (OR = 2.6, P = 0.01). And we found a significantly higher risk of having a venous variant in women (OR = 2.4, P = 0.04). We detected no case of inferior vena cava variant. In our study, prevalence of a circum- or retroaortic left renal vein appeared higher than previously reported in the literature (9.1%). Knowledge of anatomical variants of renal vasculature is crucial and this study puts the emphasis on variations of course and number of renal vessels. Those variations are not so uncommon and should be known by radiologists and also by surgeons. Their knowledge has major clinical implications in practice and it contributes to the safety of renal and retroperitoneal surgery. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  18. Urbanization: the pipelines ROW (Right-of-Way) future

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Gilberto; Malzone, Vivian de Araujo Oliveira [TRANSPETRO - PETROBRAS Transporte S.A., Rio de Janeiro, RJ (Brazil)

    2009-07-01

    The accelerated process of urbanization that is shifting the aspects of Brazilian cities - most clearly in South East and South region states - is inherently involved with decayed levels of quality of life and little or any concern at all with the sustainability of such urban expansion. Besides the social difficulties generated from this non-planned growth - mainly in the cities' outskirts - there are many questions related to urbanization that should be reconsidered such as water, soil and air pollution; lack of water resources; floods, insufficient public transport and traffic problems; urban infra-structure and lodging privations and inadequate soil installment. This paper aims at showing how this disordered urban growth plays an important role on PETROBRAS' pipeline right of way located at the great cities urban areas, more specifically the Urban Right Of Way that cross the metropolitan region of the city of Sao Paulo. Also, it is an objective to express how such urbanization propitiate the execution of basic infra-structure in a way of integrating habitation, sanitation, environment and geotechnical sectors with the purposes of PETROBRAS of maintaining as priority the integrity of the pipelines located on the ROW as well as the integrity of these ROW themselves. (author)

  19. Development of Magnetorheological Resistive Exercise Device for Rowing Machine

    Directory of Open Access Journals (Sweden)

    Vytautas Grigas

    2016-01-01

    Full Text Available Training equipment used by professional sportsmen has a great impact on their sport performance. Most universal exercisers may help only to improve the general physical condition due to the specific kinematics and peculiar resistance generated by their loading units. Training of effective techniques and learning of psychomotor skills are possible only when exercisers conform to the movements and resistance typical for particular sports kinematically and dynamically. Methodology of developing a magnetorheological resistive exercise device for generating the desired law of passive resistance force and its application in a lever-type rowing machine are described in the paper. The structural parameters of a controllable hydraulic cylinder type device were found by means of the computational fluid dynamics simulation performed by ANSYS CFX software. Parameters describing the magnetorheological fluid as non-Newtonian were determined by combining numerical and experimental research of the resistance force generated by the original magnetorheological damper. A structural scheme of the device control system was developed and the variation of the strength of magnetic field that affects the magnetorheological fluid circulating in the device was determined, ensuring a variation of the resistance force on the oar handle adequate for the resistance that occurs during a real boat rowing stroke.

  20. Development of Magnetorheological Resistive Exercise Device for Rowing Machine.

    Science.gov (United States)

    Grigas, Vytautas; Šulginas, Anatolijus; Žiliukas, Pranas

    2015-01-01

    Training equipment used by professional sportsmen has a great impact on their sport performance. Most universal exercisers may help only to improve the general physical condition due to the specific kinematics and peculiar resistance generated by their loading units. Training of effective techniques and learning of psychomotor skills are possible only when exercisers conform to the movements and resistance typical for particular sports kinematically and dynamically. Methodology of developing a magnetorheological resistive exercise device for generating the desired law of passive resistance force and its application in a lever-type rowing machine are described in the paper. The structural parameters of a controllable hydraulic cylinder type device were found by means of the computational fluid dynamics simulation performed by ANSYS CFX software. Parameters describing the magnetorheological fluid as non-Newtonian were determined by combining numerical and experimental research of the resistance force generated by the original magnetorheological damper. A structural scheme of the device control system was developed and the variation of the strength of magnetic field that affects the magnetorheological fluid circulating in the device was determined, ensuring a variation of the resistance force on the oar handle adequate for the resistance that occurs during a real boat rowing stroke.

  1. Effects of drag factor on physiological aspects of rowing.

    Science.gov (United States)

    Kane, D A; Jensen, R L; Williams, S E; Watts, P B

    2008-05-01

    This study examined the effects of two resistances, or "drag factors" on selected physiological variables during incremental progressive rowing tests (seven 3-min stages) on a Concept2 ergometer. Subjects were seven male and seven female university club rowers. Their mean age, body mass and height were 19.6 +/- 1.5 years, 72.7 +/- 8.0 kg, and 172.2 +/- 7.5 cm, respectively. Progressive tests were conducted using drag factors 100 (D100) and 150 (D150) before the spring racing season. Values were determined for the following physiological variables: ventilation (V.E), oxygen uptake (V.O2), heart rate (HR), blood lactate concentration (BLC), respiratory exchange ratio (R) and rowing economy (W/V.O2). Comparisons across all six submaximal stages showed no significant difference between D(100) and D(150) for any of the variables measured (p > .05). Maximal V.E(max) was significantly greater at D100 than D150 (p D100 than at D150, though not significantly so. The mean D100-D150 differences in V.E and SR for each stage were significantly correlated (r = 0.76, p < .01), suggesting drag factor may affect V.E via SR.

  2. Mastering Energy Management During Rowing Using Virtual Reality

    Directory of Open Access Journals (Sweden)

    Verbrugge Luc

    2011-12-01

    Full Text Available This study focused on one of the most important factors in rowing performance which is the ability demonstrated by elite rowers to regulate their effort during a 2000m race in order to produce their best performance. Experts are known to adopt a particular pacing strategy with a fast-start profile. The purpose of our study was to test by using virtual reality whether novice rowers were able to acquire this energy management skill during a 2000m race, with positive consequences for their rowing performance. Participants from the Avatar group were instructed to track a virtual boat, which velocity was previously calibrated to follow the appropriate to-be-learned velocity profile. This group was contrasted with a control group, which followed a classic training procedure. Our results indicate that the avatar group improved its performance (decrease in race duration, learned and maintained the expert profile. These effects were absent in the control group. Together, these results indicate that virtual reality can be used to accelerate the learning of energy-related skills.

  3. CT and MR imaging of the thoracic aorta

    Directory of Open Access Journals (Sweden)

    Di Cesare Ernesto

    2016-01-01

    Full Text Available At present time, both CT and MRI are valuable techniques in the study of the thoracic aorta. Nowadays, CT represents the most widely employed technique for the study of the thoracic aorta. The new generation CTs show sensitivities up to 100% and specificities of 98-99%. Sixteen and wider row detectors provide isotropic pixels, mandatory for the ineludible longitudinal reconstruction. The main limits are related to the X-ray dose expoure and the use of iodinated contrast media. MRI has great potential in the study of the thoracic aorta. Nevertheless, if compared to CT, acquisition times remain longer and movement artifact susceptibility higher. The main MRI disadvantages are claustrophobia, presence of ferromagnetic implants, pacemakers, longer acquisition times with respect to CT, inability to use contrast media in cases of renal insufficiency, lower spatial resolution and less availability than CT. CT is preferred in the acute aortic disease. Nevertheless, since it requires iodinated contrast media and X-ray exposure, it may be adequately replaced by MRI in the follow up of aortic diseases. The main limitation of MRI, however, is related to the scarce visibility of stents and calcifications.

  4. Muscle Synergies of Untrained Subjects during 6 min Maximal Rowing on Slides and Fixed Ergometer

    Directory of Open Access Journals (Sweden)

    Shazlin Shaharudin

    2014-12-01

    Full Text Available The slides ergometer (SE was an improvisation from fixed ergometer (FE to bridge the gap of mechanics between ergometer rowing and on-water rowing. The specific mechanical constraints of these two types of ergometers may affect the pattern of muscle recruitment, coordination and adaptation. The main purpose of this study was to evaluate the muscle synergy during 6 minutes maximal rowing on slides (SE and fixed ergometers (FE. The laterality of muscle synergy was also examined. Surface electromyography activity, power output, heart rate, stroke length and stroke rate were analyzed from nine physically active subjects to assess the rowing performance. Physically active subjects, who were not specifically trained in rowing, were chosen to exclude the training effect on muscle synergy. Principal component analysis (PCA with varimax rotation was applied to extract muscle synergy. Three muscle synergies were sufficient to explain the majority of variance in SE (94.4 ± 2.2 % and FE (92.8 ± 1.7 %. Subjects covered more rowing distance, exerted greater power output and attained higher maximal heart rate during rowing on SE than on FE. The results proved the flexibility of muscle synergy to adapt to the mechanical constraints. Rowing on SE emphasized on bi-articular muscles contrary to rowing on FE which relied on cumulative effect of trunk and upper limb muscles during propulsive phase.

  5. Biomechanical comparison of double-row versus transtendon single-row suture anchor technique for repair of the grade Ⅲ partial articular-sided rotator cuff tears

    Institute of Scientific and Technical Information of China (English)

    ZHANG Chun-gang; ZHAO De-wei; WANG Wei-ming; REN Ming-fa; LI Rui-xin; YANG Sheng; LIU Yu-peng

    2010-01-01

    Background For partial-thickness tears of the rotator cuff, double-row fixation and transtendon single-row fixation restore insertion site anatomy, with excellent results. We compared the biomechanical properties of double-row and transtendon single-row suture anchor techniques for repair of grade Ⅲ partial articular-sided rotator cuff tears.Methods In 10 matched pairs of fresh-frozen sheep shoulders, the infraspinatus tendon from 1 shoulder was repaired with a double-row suture anchor technique. This comprised placement of 2 medial anchors with horizontal mattress sutures at an angle of .≤45° into the medial margin of the infraspinatus footprint, just lateral to the articular surface, and 2 lateral anchors with horizontal mattress sutures. Standardized, 50% partial, articular-sided infraspinatus lesions were created in the contralateral shoulder. The infraspinatus tendon from the contralateral shoulder was repaired using two anchors with transtendon single-row mattress sutures. Each specimen underwent cyclic loading from 10 to 100 N for 50 cycles, followed by tensile testing to failure. Gap formation and strain over the footprint area were measured using a motion capture system; stiffness and failure load were determined from testing data.Results Gap formation for the transtendon single-row repair was significantly smaller (P <0.05) when compared with the double-row repair for the first cycle ((1.74±0.38) mm vs. (2.86±0.46) mm, respectively) and the last cycle ((3.77±0.45) mm vs. (5.89±0.61) mm, respectively). The strain over the footprint area for the transtendon single-row repair was significantly smaller (P <0.05) when compared with the double-row repair. Also, it had a higher mean ultimate tensile load and stiffness.Conclusions For grade Ⅲ partial articular-sided rotator cuff tears, transtendon single-row fixation exhibited superior biomechanical properties when compared with double-row fixation.

  6. Abdominal and Pelvic CT

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    Full Text Available ... the scanner at one time such as with MRI. If an intravenous contrast material is used, you ... CT is less sensitive to patient movement than MRI. CT can be performed if you have an ...

  7. Computed Tomography (CT) -- Head

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    Full Text Available ... of the Head? What is CT Scanning of the Head? Computed tomography, more commonly known as a ... of page What are some common uses of the procedure? CT scanning of the head is typically ...

  8. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... the Sinuses? What is CT (Computed Tomography) of the Sinuses? Computed tomography, more commonly known as a ... of page What are some common uses of the procedure? CT of the sinuses is primarily used ...

  9. Computed Tomography (CT) -- Head

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    Full Text Available ... view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ... lives. CT has been shown to be a cost-effective imaging tool for a wide range of ...

  10. Computed Tomography (CT) -- Sinuses

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  11. Abdominal and Pelvic CT

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  12. Computed Tomography (CT) -- Head

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  13. Computed Tomography (CT) -- Sinuses

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  14. Abdominal and Pelvic CT

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  15. Computed Tomography (CT) -- Head

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  16. Computed Tomography (CT) -- Sinuses

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  17. Abdominal and Pelvic CT

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    Full Text Available ... scanners to obtain multiple slices in a single rotation. These scanners, called multislice CT or multidetector CT, ... prescribed procedure with your doctor, the medical facility staff and/or your insurance provider to get a ...

  18. Computed Tomography (CT) -- Head

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    Full Text Available ... scanners to obtain multiple slices in a single rotation. These scanners, called multislice CT or multidetector CT, ... prescribed procedure with your doctor, the medical facility staff and/or your insurance provider to get a ...

  19. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... scanners to obtain multiple slices in a single rotation. These scanners, called multislice CT or multidetector CT, ... prescribed procedure with your doctor, the medical facility staff and/or your insurance provider to get a ...

  20. CT Grading of Otosclerosis

    National Research Council Canada - National Science Library

    Lee, T.C; Aviv, R.I; Chen, J.M; Nedzelski, J.M; Fox, A.J; Symons, S.P

    2009-01-01

    ...: The CT grading system for otosclerosis was proposed by Symons and Fanning in 2005. The purpose of this study was to determine if this CT grading system has high interobserver and intraobserver agreement...

  1. Abdominal and Pelvic CT

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    Full Text Available ... CT scanner technique will be adjusted to their size and the area of interest to reduce the ... Patient undergoing computed tomography (CT) scan View full size with caption Pediatric Content Some imaging tests and ...

  2. Computed Tomography (CT) -- Head

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    Full Text Available ... CT scanner technique will be adjusted to their size and the area of interest to reduce the ... Patient undergoing computed tomography (CT) scan. View full size with caption Pediatric Content Some imaging tests and ...

  3. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... CT scanner technique will be adjusted to their size and the area of interest to reduce the ... Patient undergoing computed tomography (CT) scan. View full size with caption Pediatric Content Some imaging tests and ...

  4. Abdominal and Pelvic CT

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    Full Text Available ... page How should I prepare for the CT scan? You should wear comfortable, loose-fitting clothing to ... studied. top of page How is the CT scan performed? The technologist begins by positioning you on ...

  5. Computed Tomography (CT) -- Head

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    Full Text Available ... be viewed on a computer monitor, printed on film or transferred to a CD or DVD. CT ... distinguished from one another on an x-ray film or CT electronic image. In a conventional x- ...

  6. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... be viewed on a computer monitor, printed on film or transferred to a CD or DVD. CT ... distinguished from one another on an x-ray film or CT electronic image. In a conventional x- ...

  7. Abdominal and Pelvic CT

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    Full Text Available ... be viewed on a computer monitor, printed on film or transferred to a CD or DVD. CT ... distinguished from one another on an x-ray film or CT electronic image. In a conventional x- ...

  8. Computed Tomography (CT) -- Head

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    Full Text Available ... top of page What are the benefits vs. risks? Benefits CT scanning is painless, noninvasive and accurate. ... CT scans should have no immediate side effects. Risks There is always a slight chance of cancer ...

  9. Abdominal and Pelvic CT

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    Full Text Available ... top of page What are the benefits vs. risks? Benefits Viewing a CT scan, an experienced radiologist ... CT scans should have no immediate side effects. Risks There is always a slight chance of cancer ...

  10. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... top of page What are the benefits vs. risks? Benefits A CT scan is one of the ... CT scans should have no immediate side effects. Risks There is always a slight chance of cancer ...

  11. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... scanners to obtain multiple slices in a single rotation. These scanners, called multislice CT or multidetector CT, ... special pediatric considerations. The teddy bear denotes child-specific content. Related Articles and Media Magnetic Resonance Imaging ( ...

  12. Computed Tomography (CT) -- Head

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    Full Text Available ... scanners to obtain multiple slices in a single rotation. These scanners, called multislice CT or multidetector CT, ... special pediatric considerations. The teddy bear denotes child-specific content. Related Articles and Media Radiation Dose in ...

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    Full Text Available ... scanners to obtain multiple slices in a single rotation. These scanners, called multislice CT or multidetector CT, ... special pediatric considerations. The teddy bear denotes child-specific content. Related Articles and Media Ultrasound - Abdomen X- ...

  14. Abdominal and Pelvic CT

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    Full Text Available ... CT scanning is fast, painless, noninvasive and accurate. In emergency cases, it can reveal internal injuries and ... generated during a CT scan can be reformatted in multiple planes, and can even generate three-dimensional ...

  15. Computed Tomography (CT) -- Sinuses

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  16. Abdominal and Pelvic CT

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    Full Text Available ... the cause of unexplained pain. CT scanning is fast, painless, noninvasive and accurate. In emergency cases, it ... additional view capabilities. Modern CT scanners are so fast that they can scan through large sections of ...

  17. Computed Tomography (CT) -- Head

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    Full Text Available ... which may be causing hearing problems. determine whether inflammation or other changes are present in the paranasal ... CT scans . CT is not sensitive in detecting inflammation of the meninges —the membranes covering the brain. ...

  18. Computed Tomography (CT) -- Head

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    Full Text Available ... a stroke. a stroke, especially with a new technique called Perfusion CT. brain tumors. enlarged brain cavities ( ... brain. assess aneurysms or arteriovenous malformations through a technique called CT angiography. For more information, see the ...

  19. Computed Tomography (CT) -- Head

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    Full Text Available ... view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ... to urinate; however, this is actually a contrast effect and subsides quickly. When you enter the CT ...

  20. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ... to urinate; however, this is actually a contrast effect and subsides quickly. When you enter the CT ...

  1. Cardiac CT Scan

    Science.gov (United States)

    ... combine these pictures to create a three-dimensional (3D) model of the whole heart. This imaging test ... findings from earlier chest x rays. Different CT scanners are used for different purposes. A multidetector CT ...

  2. Computed Tomography (CT) -- Head

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    Full Text Available ... of the Head? What is CT Scanning of the Head? Computed tomography, more commonly known as a ... of page What are some common uses of the procedure? CT scanning of the head is typically ...

  3. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... the Sinuses? What is CT (Computed Tomography) of the Sinuses? Computed tomography, more commonly known as a ... of page What are some common uses of the procedure? CT of the sinuses is primarily used ...

  4. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... benefits vs. risks? Benefits A CT scan is one of the safest means of studying the sinuses. ... CT scanning provides very detailed images of many types of tissue as well as the lungs, bones, ...

  5. Gallstone ileus: CT findings

    Energy Technology Data Exchange (ETDEWEB)

    Delabrousse, E.; Bartholomot, B.; Sohm, O.; Kastler, B. [Dept. of Radiology A, CHU Jean Minjoz, University of Besancon (France); Wallerand, H. [Dept. of Surgery, CHU Jean Minjoz, University of Besancon (France)

    2000-06-01

    Gallstone ileus is a rare complication of recurrent gallstone cholecystitis. The classic radiographic triad of small bowel obstruction, pneumobilia and ectopic gallstone on abdominal plain radiograph is described with CT imaging. Because of the better resolution of CT compared with abdominal radiography and its recent accession to emergency use, radiologists should be aware of CT findings of gallstone ileus. We report a case in which gallstone ileus was initially diagnosed by CT. (orig.)

  6. Abdominal and Pelvic CT

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    Full Text Available ... microphone. top of page How does the procedure work? In many ways CT scanning works very much like other x-ray examinations. Different ... scanners to obtain multiple slices in a single rotation. These scanners, called multislice CT or multidetector CT, ...

  7. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... microphone. top of page How does the procedure work? In many ways CT scanning works very much like other x-ray examinations. Different ... scanners to obtain multiple slices in a single rotation. These scanners, called multislice CT or multidetector CT, ...

  8. Computed Tomography (CT) -- Head

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    Full Text Available ... microphone. top of page How does the procedure work? In many ways CT scanning works very much like other x-ray examinations. Different ... scanners to obtain multiple slices in a single rotation. These scanners, called multislice CT or multidetector CT, ...

  9. Computed Tomography (CT) -- Head

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    Full Text Available ... a sudden severe headache. a blood clot or bleeding within the brain shortly after a patient exhibits symptoms of a stroke. a ... CT scanning may eliminate the need for exploratory surgery and surgical biopsy. No radiation remains in a patient's body after a CT examination. X-rays used in CT ...

  10. CT angiography and CT perfusion in acute ischemic stroke

    NARCIS (Netherlands)

    Seeters, T. van

    2016-01-01

    CT angiography and CT perfusion are used in patients with acute ischemic stroke for diagnostic purposes and to select patients for treatment. In this thesis, the reproducibility of CT angiography and CT perfusion is examined, the additional value of CT angiography and CT perfusion for stroke outcome

  11. Role of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography in diagnosis and management of pancreatic cancer; comparison with multidetector row computed tomography, magnetic resonance imaging and endoscopic ultrasonography.

    Science.gov (United States)

    Ergul, N; Gundogan, C; Tozlu, M; Toprak, H; Kadıoglu, H; Aydin, M; Cermik, T F

    2014-01-01

    We aimed to analyze the contribution of (18)F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) imaging to the diagnosis and management of pancreatic cancer compared with multidetector row computed tomography (MDCT), magnetic resonance imaging (MRI) and endoscopic ultrasonography (EUS). We retrospectively scanned the data of 52 patients who were referred for FDG PET/CT imaging for evaluation of pancreatic lesions greater than 10mm. The diagnostic performances of 4 imaging methods and the impact of PET/CT on the management of pancreatic cancer were defined. Pancreatic adenocarcinoma was diagnosed in 33 of 52 patients (63%), 15 patients had benign diseases of pancreas (29%), and 4 patients were normal (8%). Sensitivity and NPV of EUS and PET/CT were equal (100%) and higher than MDCT and MRI. Specificity, PPV and NPV of PET/CT were significantly higher than MDCT. However, sensitivities of two imaging methods were not significantly different. There was no significant difference between PET/CT and MRI and EUS for these values. When the cut-off value of SUVmax was 3.2, the most effective sensitivity and specificity values were obtained. PET/CT contributed to the management of pancreatic cancer in 30% of patients. FDG PET/CT is a valuable imaging method for the diagnosis and management of pancreatic cancer, especially when applied along with EUS as first line diagnostic tools. Copyright © 2013 Elsevier España, S.L. and SEMNIM. All rights reserved.

  12. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... News Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography (CT) ... are the limitations of Children's CT? What is Children's CT? Computed tomography, more commonly known as a ...

  13. Your Radiologist Explains CT Colonography

    Medline Plus

    Full Text Available ... CT Angiography Video: Myelography Video: CT of the Heart Video: Radioiodine I-131 Therapy Radiology and You ... CT Angiography Video: Myelography Video: CT of the Heart Video: Radioiodine I-131 Therapy Radiology and You ...

  14. Row Spacing in Relation to Competition for Limited Resources in Soybean (Glycine Max L.Merrill)

    Institute of Scientific and Technical Information of China (English)

    LIU Xiao-bing; S J Herbert; JIN Jian; M Hashemi; WANG Guang-hua

    2004-01-01

    Growing soybeans in different row-spacings introduces competition. Competition begins when the immediate supply of a single necessary factor falls below the combined demands of all plants. This paper reviews the main competition factors of genotypes, light, water, nutrients and weed in responses to row spacings for the past four decades. It demonstrated that responses of soybean genotypes to row width differ among cultivars, which depend on seasonal rainfall and irrigation. Determinate types produce more yield in narrow-rows, and cultivars with lodging resistance should be adopted in narrow-spacings, but indeterminate soybean should also be used to optimize yields in certain system. Narrow-compared with wide-row soybean (Glycine max) cultivation increases light interception (LI) and dominant components for the increase come from LAI, light extinction coefficients and branch types. Water use efficiency (WUE) and evapotranspiration are not influenced by row spacing, but seed yield could be increased if irrigation is applied. Nutrient uptake is significantly affected by row spacing, seed yields and uptake of N, P, K in plants increases with decreasing row spacing, and the effects depend on the fertilizer levels. Other factors rather than row spacing affect nitrogen fixation. Weed density, peak time and periodicity of weed emergence are not affected by row spacing, but better complementary weed control by the herbicides at the used doses can be obtained in narrow spacing due to the reduced weed number and dry weight. More researches are required to investigate the physiological responses, nutrient and water uptake and translocation, light utilization at different layers of canopy and soil environment changes in different row-spacings.

  15. The Effect of Performing Bi- and Unilateral Row Exercises on Core Muscle Activation.

    Science.gov (United States)

    Saeterbakken, A; Andersen, V; Brudeseth, A; Lund, H; Fimland, M S

    2015-11-01

    The purpose of the study was to compare core muscle activation in 3 different row exercises (free-weight bent-over row, seated cable row and machine row) performed unilaterally and bilaterally, at matched effort levels. 15 resistance-trained men (26.0±4.4 years, 81.0±9.5 kg, 1.81±0.07 m) performed the exercises in randomized order. For erector spinae and multifidus, EMG activities in unilateral machine- and cable row were 60-63% and 74-78% of the bilateral performance (P≤0.036). For external oblique, the EMG activities recorded during bilateral exercises were 37-41% of the unilateral performance (P≤0.010). In unilateral cable- and machine rows, the EMG activities in external oblique and multifidus were 50-57% and 70-73% of the free-weight row (P≤0.002). In bilateral free-weight row, EMG activity in erector spinae was greater than bilateral machine- (+34%, P=0.004) and unilateral free-weight rows (+12%, P=0.016). For rectus abdominis there were no significant differences between conditions. In conclusion, 1) free-weight row provided greater EMG activity in erector spinae (bilaterally and unilaterally) and multifidus (unilaterally) than machine row; 2) unilateral performance of exercises activated the external oblique more than bilateral performance, regardless of exercise; and 3) generally bilateral performance of exercises provided higher erector spinae and multifidus EMG activity compared to unilateral performance.

  16. Transfer of complex skill learning from virtual to real rowing.

    Directory of Open Access Journals (Sweden)

    Georg Rauter

    Full Text Available Simulators are commonly used to train complex tasks. In particular, simulators are applied to train dangerous tasks, to save costs, and to investigate the impact of different factors on task performance. However, in most cases, the transfer of simulator training to the real task has not been investigated. Without a proof for successful skill transfer, simulators might not be helpful at all or even counter-productive for learning the real task. In this paper, the skill transfer of complex technical aspects trained on a scull rowing simulator to sculling on water was investigated. We assume if a simulator provides high fidelity rendering of the interactions with the environment even without augmented feedback, training on such a realistic simulator would allow similar skill gains as training in the real environment. These learned skills were expected to transfer to the real environment. Two groups of four recreational rowers participated. One group trained on water, the other group trained on a simulator. Within two weeks, both groups performed four training sessions with the same licensed rowing trainer. The development in performance was assessed by quantitative biomechanical performance measures and by a qualitative video evaluation of an independent, blinded trainer. In general, both groups could improve their performance on water. The used biomechanical measures seem to allow only a limited insight into the rowers' development, while the independent trainer could also rate the rowers' overall impression. The simulator quality and naturalism was confirmed by the participants in a questionnaire. In conclusion, realistic simulator training fostered skill gains to a similar extent as training in the real environment and enabled skill transfer to the real environment. In combination with augmented feedback, simulator training can be further exploited to foster motor learning even to a higher extent, which is subject to future work.

  17. Biomechanical Performance of Medial Row Suture Placement Relative to the Musculotendinous Junction in Transosseous Equivalent Suture Bridge Double-Row Rotator Cuff Repair.

    Science.gov (United States)

    Virk, Mandeep S; Bruce, Benjamin; Hussey, Kristen E; Thomas, Jacqueline M; Luthringer, Tyler A; Shewman, Elizabeth F; Wang, Vincent M; Verma, Nikhil N; Romeo, Anthony A; Cole, Brian J

    2017-02-01

    To compare the biomechanical performance of medial row suture placement relative to the musculotendinous junction (MTJ) in a cadaveric transosseous equivalent suture bridge (TOE-SB) double-row (DR) rotator cuff repair (RCR) model. A TOE-SB DR technique was used to reattach experimentally created supraspinatus tendon tears in 9 pairs of human cadaveric shoulders. The medial row sutures were passed either near the MTJ (MTJ group) or 10 mm lateral to the MTJ (rotator cuff tendon [RCT] group). After the supraspinatus repair, the specimens underwent cyclic loading and load to failure tests. The localized displacement of the markers affixed to the tendon surface was measured with an optical tracking system. The MTJ group showed a significantly higher (P = .03) medial row failure (5/9; 3 during cyclic testing and 2 during load to failure testing) compared with the RCT group (0/9). The mean number of cycles completed during cyclic testing was lower in the MTJ group (77) compared with the RCT group (100; P = .07) because 3 specimens failed in the MTJ group during cyclic loading. There were no significant differences between the 2 study groups with respect to biomechanical properties during the load to failure testing. In a cadaveric TOE-SB DR RCR model, medial row sutures through the MTJ results in a significantly higher rate of medial row failure. In rotator cuff tears with tendon tissue loss, passage of medial row sutures through the MTJ should be avoided in a TOE-SB RCR technique because of the risk of medial row failure. Copyright © 2016. Published by Elsevier Inc.

  18. Marketing cardiac CT programs.

    Science.gov (United States)

    Scott, Jason

    2010-01-01

    There are two components of cardiac CT discussed in this article: coronary artery calcium scoring (CACS) and coronary computed tomography angiography (CCTA).The distinctive advantages of each CT examination are outlined. In order to ensure a successful cardiac CT program, it is imperative that imaging facilities market their cardiac CT practices effectively in order to gain a competitive advantage in this valuable market share. If patients receive quality care by competent individuals, they are more likely to recommend the facility's cardiac CT program. Satisfied patients will also be more willing to come back for any further testing.

  19. Application of large aperture spiral CT in radiotherapy simulation positioning%大孔径螺旋CT在放疗模拟定位中的应用研究

    Institute of Scientific and Technical Information of China (English)

    李雪南; 修霞; 李高峰

    2013-01-01

    目的:探讨大孔径16排螺旋CT在放疗模拟定位中的应用。方法:应用大孔径16排螺旋CT进行乳腺癌保乳术后根治性放疗乳腺切线野的CT模拟定位,并对CT模拟定位技术与传统X射线模拟定位技术进行比较,同时与单排螺旋CT的图像进行比较。结果:大孔径16排螺旋CT在放疗模拟定位中的应用避免了因患者体位受限而造成的误差;大孔径16排螺旋CT模拟机的定位验证误差均优于传统X射线模拟机;其图像质量优于单排螺旋CT。结论:大孔径16排螺旋CT模拟定位机的应用,使得放疗定位更加精确,计划和治疗更加准确。%Objective:To discuss application of large aperture 16 row spiral CT in radiotherapy simulation positioning. Methods: To apply CT simulation positioning with large aperture 16 row spiral CT for the breast tangential field by early breast cancer after breast conserving surgery and radical radiotherapy. Compare CT-simulation and X-ray conventional positioning technique and Compare large aperture 16 row spiral CT and single row spiral CT image. Results: The application of large aperture 16 row spiral CT avoided the error because of body limited. Large aperture 16 row spiral CT simulation position validation error is superior to X-ray positioning. Its image quality is better than that of single row spiral CT. Conclusion:The application of large aperture 16 row spiral CT make simulation positioning more accurate, planned and treatment more accurate, it can provide guarantee of accurate simulation positioning for accurate plan and treatment.

  20. Building Generalized Inverses of Matrices Using Only Row and Column Operations

    Science.gov (United States)

    Stuart, Jeffrey

    2010-01-01

    Most students complete their first and only course in linear algebra with the understanding that a real, square matrix "A" has an inverse if and only if "rref"("A"), the reduced row echelon form of "A", is the identity matrix I[subscript n]. That is, if they apply elementary row operations via the Gauss-Jordan algorithm to the partitioned matrix…

  1. Building Generalized Inverses of Matrices Using Only Row and Column Operations

    Science.gov (United States)

    Stuart, Jeffrey

    2010-01-01

    Most students complete their first and only course in linear algebra with the understanding that a real, square matrix "A" has an inverse if and only if "rref"("A"), the reduced row echelon form of "A", is the identity matrix I[subscript n]. That is, if they apply elementary row operations via the Gauss-Jordan algorithm to the partitioned matrix…

  2. Looking at Row and its Functions in the Khaghani’s Poem

    Directory of Open Access Journals (Sweden)

    Dr. M. Ruhani

    Full Text Available According to researchers, rows can be one of the main components of the ancient Persian poetry as Iranian-made talent and initiative. Row as one of the pillars of the musin aside, has played a major role in classical Persian poetry, and the past Persian chorus According to compose poems of rows shown. In the early Persian poetry, little of the row is used but the evolution of the Persian poetry to the inputs, Application of the row will have more go to the review of the application of the simple parts of the hard parts.One of the poets who have shown special attention to the row and application forms are high-frequency line in his poems, is khaghani. In these essays, is trying to hit the angle of the line in the poem is Khaghani. We provide accurate statistics of the poem with row and without row and types of rows was investigated across the court poet. His poems have a row and was much more than non row poems.Statistical analysis shows that 815 of 1212 khaghani`s poem have rows that this number are included 20/68% of all poems. Study of row in different form is show that poem with row appreciably higher than poem without row. 81/77% of sonnets, 39/64% of odes, 88/54% of the quetrains, 22/64% parts and 66/79% of his small odes have row. The types of row in Khaghani`s poem include: verb, noun (noun phrase, letters, adverbs, pronouns, adjectives and phrases, or sentences (such as overnight. But the verbical row (70% are mostly used in his poetry. In this article we will discuss the functions of the rows in the poem of khaghani and concluded that the main functions of the poet`s row are as follows:1-Create unity between poet and audienceWhen the reader can to guess the word or phrase in a particular situation after a couplet, its sure that he is partner with poet in lyrics creation2- Row coordinate with the theme of the poemCoordination the row and poetry Thread is important near the great poets such as khaghani. Ofcourse creating of this

  3. Row Reduction Applied to Decoding of Rank Metric and Subspace Codes

    DEFF Research Database (Denmark)

    Puchinger, Sven; Nielsen, Johan Sebastian Rosenkilde; Li, Wenhui

    2017-01-01

    We show that decoding of ℓ-Interleaved Gabidulin codes, as well as list-ℓ decoding of Mahdavifar–Vardy (MV) codes can be performed by row reducing skew polynomial matrices. Inspired by row reduction of F[x] matrices, we develop a general and flexible approach of transforming matrices over skew...

  4. Rowing increases stroke volume and cardiac output to a greater extent than cycling.

    Science.gov (United States)

    Horn, P; Ostadal, P; Ostadal, B

    2015-01-01

    Exercise stimulates increases in heart rate (HR), stroke volume (SV) and cardiac output (CO). These adaptive mechanisms are strongly dependent on the type of exercise. Both rowing and cycling are widely used for physical training worldwide; however, evidence regarding the differences in major hemodynamic parameters during rowing and cycling remains insufficient. Ten healthy male volunteers were randomly assigned to perform either a rowing or cycling exercise. After 20 min rest, the group who had rowed first performed the cycling exercise and vice versa. Exercise was performed at a power-to-weight ratio of 2 W/kg for 2 min. HR, SV, CO and blood pressure (BP) were measured noninvasively using pulse-wave analysis at baseline and immediately after each exercise. HR, SV and CO were significantly higher after exercise than at rest. Whereas HR was comparable between rowing and cycling, SV and CO were significantly higher after rowing than after cycling. BP was comparable among all three measurements. Rowing increased SV and CO to a greater extent than cycling, whereas HR and BP were not influenced by the type of exercise. Our data suggest that rowing leads to more extensive stimulation of cardiac contractility and/or decreases in peripheral vascular resistance compared with cycling.

  5. Influence of space of double row piles on soil arching effect

    Directory of Open Access Journals (Sweden)

    Zhao bo

    2015-02-01

    Full Text Available FLAC3d software, based on continuous theory, is used to analysis influence of space of double row piles on soil arching effect. The result shows that different from single row pile, double row piles will produce soil arching effect at front pile and rear pile severally, this phenomenon is called multiple soil arching effect; the residual load of front of front row pile will increase,the soil arch zone and the soil arching effect will decrease with the continuous increase of double row pile spacing.At the same time the soil arching effect of rear pile decreases, while the soil arching effect of front pile increases and finally the soil arching effect between front pile and rear pile will be equal.

  6. A bi-directional gap model for simulating the directional thermal radiance of row crops

    Institute of Scientific and Technical Information of China (English)

    CHEN; Liangfu; (陈良富); LIU; Qinhuo; (柳钦火); FAN; Wenjie; (范闻捷); LI; Xiaowen; (李小文); XIAO; Qing; (肖青); YAN; Guangjian; (闫广建); TIAN; Guoliang; (田国良)

    2002-01-01

    Row crops are a kind of typical vegetation canopy between discrete canopy and continuous canopy. Kimes et al. studied the directional thermal radiation of row crops using the geometrical optical model, which simplified row structure as "box" and neglected the gap among foliage and did not consider the emissivity effects. In this work we take account of the gaps along illumination and viewing directions and propose a bi-direction gap model on the basis of the idea of gap probability of discrete vegetation canopy introduced by "Li-Strahler" and inter-correlation of continuous vegetation developed by Kuusk. It can be used to explain "hot spot" effects in thermal infrared region. The gap model has been validated by field experiment on winter wheat planted in shape of rows and results show that the gap model is better than Kimes' model in describing the directionality of thermal infrared emission for row crops.

  7. Organisational and methodological aspects of experimental training programs for athletes lightweights in academic rowing

    Directory of Open Access Journals (Sweden)

    Omelchenko E.S.

    2014-03-01

    Full Text Available Purpose: develop an experimental training program for lightweight rowers in academic rowing. Material: the study involved 27 qualified athletes who are engaged in academic rowing over 6 years, age 19-22 years, with sports qualifications KMS and MS. To better design the training program was conducted to study this physical condition of athletes also took into account the opinion of the leading coaches in academic rowing that are engaged with lightweight rowers. Results: as a result of an experimental study was designed training program in academic rowing. Conclusions: Experimental training program rowing provided its use for a year and was designed in the form of blocks and aims to developing and improving endurance (speed and power, strength and maximum strength. The experimental technique that was used in the training process, was designed with the preparation phase and plan on mesocycles and microcycle.

  8. Significance of agricultural row structure on the microwave emissivity of soils

    Science.gov (United States)

    Promes, P. M.; Jackson, T. J.; O'Neill, P. E.

    1987-01-01

    A series of field experiments was carried out to extend the data base available for verifying agricultural row effect models of emissivity. The row effects model was used to simulate a data base from which an algorithm could be developed to account for row effects when the scene dielectric constant and small-scale roughness are unknown. One objective of the study was to quantify the significance of row structure and to develop a practical procedure for removing the effects of periodic row structure on the microwave emissivity of a soil in order to use the emissivity values to estimate the soil moisture. A second objective was to expand the data set available for model verification through field observations using a truck-mounted 1.4-GHz microwave radiometer.

  9. Positive ions of the first- and second-row transition metal hydrides

    Science.gov (United States)

    Pettersson, Lars G. M.; Bauschlicher, Charles W., Jr.; Langhoff, Stephen R.; Partridge, Harry

    1987-01-01

    Theoretical dissociation energies for the first- and second-row transition metal hydride positive ions are critically compared against recent experimental values obtained from ion beam reactive scattering methods. Theoretical spectroscopic parameters and dipole moments are presented for the ground and several low-lying excited states. The calculations employ large Gaussian basis sets and account for electron correlation using the single-reference single- and double-excitation configuration interaction and coupled-pair-functional methods. The Darwin and mass-velocity contributions to the relativistic energy are included in the all-electron calculations on the first-row systems using first-order perturbation theory, and in the second-row systems using the Hay and Wadt relativistic effective core potentials. The theoretical D(0) values for the second-row transition metal hydride positive ions should provide a critical measure of the experimental values, which are not as refined as many of those in the first transition row.

  10. Don't rock the boat: how antiphase crew coordination affects rowing.

    Directory of Open Access Journals (Sweden)

    Anouk J de Brouwer

    Full Text Available It is generally accepted that crew rowing requires perfect synchronization between the movements of the rowers. However, a long-standing and somewhat counterintuitive idea is that out-of-phase crew rowing might have benefits over in-phase (i.e., synchronous rowing. In synchronous rowing, 5 to 6% of the power produced by the rower(s is lost to velocity fluctuations of the shell within each rowing cycle. Theoretically, a possible way for crews to increase average boat velocity is to reduce these fluctuations by rowing in antiphase coordination, a strategy in which rowers perfectly alternate their movements. On the other hand, the framework of coordination dynamics explicates that antiphase coordination is less stable than in-phase coordination, which may impede performance gains. Therefore, we compared antiphase to in-phase crew rowing performance in an ergometer experiment. Nine pairs of rowers performed a two-minute maximum effort in-phase and antiphase trial at 36 strokes min(-1 on two coupled free-floating ergometers that allowed for power losses to velocity fluctuations. Rower and ergometer kinetics and kinematics were measured during the trials. All nine pairs easily acquired antiphase rowing during the warm-up, while one pair's coordination briefly switched to in-phase during the maximum effort trial. Although antiphase interpersonal coordination was indeed less accurate and more variable, power production was not negatively affected. Importantly, in antiphase rowing the decreased power loss to velocity fluctuations resulted in more useful power being transferred to the ergometer flywheels. These results imply that antiphase rowing may indeed improve performance, even without any experience with antiphase technique. Furthermore, it demonstrates that although perfectly synchronous coordination may be the most stable, it is not necessarily equated with the most efficient or optimal performance.

  11. New frontiers in CT imaging of airway disease

    Energy Technology Data Exchange (ETDEWEB)

    Grenier, Philippe A.; Beigelman-Aubry, Catherine [Department of Radiology, University Pierre et Marie Curie, Paris (France); Fetita, Catalin; Preteux, Francoise [Institut National des Telecommunications, Department ARTEMIS, Evry (France); Brauner, Michel W. [Avicenne Hospital, UFR SMBH Paris XIII, Bobigny (France); Lenoir, Stephane [Institut Mutualiste Montsouris, Paris (France)

    2002-05-01

    Combining helical volumetric CT acquisition and thin-slice thickness during breath hold provides an accurate assessment of both focal and diffuse airway diseases. With multiple detector rows, compared with single-slice helical CT, multislice CT can cover a greater volume, during a simple breath hold, and with better longitudinal and in-plane spatial resolution and improved temporal resolution. The result in data set allows the generation of superior multiplanar and 3D images of the airways, including those obtained from techniques developed specifically for airway imaging, such as virtual bronchography and virtual bronchoscopy. Complementary CT evaluation at suspended or continuous full expiration is mandatory to detect air trapping that is a key finding for depicting an obstruction on the small airways. Indications for CT evaluation of the airways include: (a) detection of endobronchial lesions in patients with an unexplained hemoptysis; (b) evaluation of extent of tracheobronchial stenosis for planning treatment and follow-up; (c) detection of congenital airway anomalies revealed by hemoptysis or recurrent infection; (d) detection of postinfectious or postoperative airway fistula or dehiscence; and (e) diagnosis and assessment of extent of bronchiectasis and small airway disease. Improvement in image analysis technique and the use of spirometrically control of lung volume acquisition have made possible accurate and reproducible quantitative assessment of airway wall and lumen areas and lung density. This contributes to better insights in physiopathology of obstructive lung disease, particularly in chronic obstructive pulmonary disease and asthma. (orig.)

  12. Dynamic Multidetector CT Findings of Left Atrial Myxomas Causing Mitral Valve Obstruction

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Ji Yeon [Dept. of Radiology, Soonchunhyang University College of Medicine, Bucheon (Korea, Republic of); Kim, Dong Hun [Dept. of Radiology, Chosun University College of Medicine, Gwangju (Korea, Republic of); Seo, Hye Sun [Dept. of Radiology, Soonchunhyang University College of Medicine, Bucheon (Korea, Republic of); Her, Keun [Dept. of Radiology, Soonchunhyang University College of Medicine, Bucheon (Korea, Republic of); Kim, Hee Kyung [Dept. of Radiology, Soonchunhyang University College of Medicine, Bucheon (Korea, Republic of)

    2011-07-15

    We report multidetector row CT (MDCT) findings of two left atrial myxomas causing mitral valve obstruction and dyspnea of patients. Cardiac MDCT showed well-defined left atrial masses attached to the interatrial septum and shifting of tumors into the left ventricle causing mitral valve obstruction during diastole in a 37-year-old male and in a 69-year-old female. Also, we observed intratumoral hemorrhage in the second case. Myxomas were resected and the patients were discharged without dyspnea.

  13. Multidetector CT imaging of mechanical prosthetic heart valves: quantification of artifacts with a pulsatile in-vitro model

    Energy Technology Data Exchange (ETDEWEB)

    Symersky, Petr [Onze Lieve Vrouwe Gasthuis, Department of Cardiothoracic Surgery, Oosterpark 9, P.O box 95500, Amsterdam (Netherlands); Academic Medical Center, Department of Cardiothoracic Surgery, Amsterdam (Netherlands); Budde, Ricardo P.J. [University Medical Center, Department of Radiology, Utrecht (Netherlands); Westers, Paul [Julius Center for Health Sciences and Primary Care, Department of Biostatistics, Utrecht (Netherlands); Mol, Bas A.J.M. de [Academic Medical Center, Department of Cardiothoracic Surgery, Amsterdam (Netherlands); University of Technology Eindhoven, Department of Biomedical Engineering, Eindhoven (Netherlands); Prokop, Mathias [Radboud University Nijmegen Medical Center, Department of Radiology, Nijmegen (Netherlands)

    2011-10-15

    Multidetector computed tomography (MDCT) can detect the cause of prosthetic heart valve (PHV) dysfunction but is hampered by valve-induced artifacts. We quantified artifacts of four PHV using a pulsatile in-vitro model and assessed the relation to leaflet motion and valve design. A Medtronic Hall tilting disc (MH), and Carbomedics (CM), St Jude (SJM), and ON-X bileaflet valves underwent CT in an in-vitro model using retrospective gating with a 64 detector CT system in stationary and pulsatile conditions. Artifacts and radiopaque component volumes were quantified with thresholds based on surrounding structures and valvular components. Hypodense artifacts volumes (mm{sup 3}) were 1,029 {+-} 147, 535 {+-} 53, 371 {+-} 16, and 366 {+-} 18 for the SJM, MH, CM and ON-X valves (p < 0.001 except for the latter two valves p = 0.43). Hyperdense artifact volumes were 3,546 {+-} 141, 2,387 {+-} 103, 2,003 {+-} 102, and 3,033 {+-} 31 for the SJM, MH, CM and ON-X valve, respectively (all differences p < 0.001). Leaflet motion affected hypodense (F = 41.5, p < 0.001) and hyperdense artifacts (F = 53.7, p < 0.001). Closed and moving leaflets were associated with the least and the most artifacts respectively (p < 0.001, both artifact types). Both valve design and leaflet motion affect PHV-induced artifacts. Best imaging results may be expected for the CM valve during phases in which the leaflets are closed. (orig.)

  14. Coronary CT angiography in symptomatic patients

    Energy Technology Data Exchange (ETDEWEB)

    Becker, C.R. [Inst. of Radiologic Diagnostic, Univ. of Munich, Klinikum Grosshadern, Munich (Germany)

    2005-02-01

    The currently best available spatial and temporal resolution for retrospectively ECG gated coronary multi-detector-row CT angiography is 0.4 mm and 165 ms, respectively. These acquisition parameters are already rather close to cardiac catheter. Studies so far compared non-invasive coronary CT and convention angiography for the detection of coronary artery stenoses. The most promising result reported by all authors was the high negative predictive value of the CTA. It now needs to be determined if CTA is a reliable tool to rule out coronary artery stenoses in a patient cohort with low likelihood of CAD, such as those with atypical chest pain or ambiguous stress test. CTA may furthermore establish as a rapid and widely available tool to detect vulnerable plaques or intracoronary thrombus in patients with acute coronary syndrome and unstable angina. In patients with chronic stable angina, tools that determine myocardial ischemia under stress such as SPECT and MRI are probably better suited to determine the relevance of coronary artery stenoses. In this particular cohort, by displaying the extent and morphology of coronary atherosclerosis, CTA may help to direct the therapy to either intervention or surgery. (orig.)

  15. Colin Rowe y el equilibrio dinámico

    Directory of Open Access Journals (Sweden)

    Pablo López Martín

    2015-05-01

    Full Text Available ResumenEn 1944 Gyorgy Kepes publica el que sin duda será su texto más influyente, El lenguaje de la visión. En él Kepes trata de llevar a cabo una guía que explique la gramática y la sintaxis del fenómeno de la visión, y que sirva como herramienta para enfrentarse al arte como experiencia puramente sensorial, desprovista de toda carga literaria, semántica o sentimental.De todos los conceptos que Kepes desgrana en su ensayo quizá el más determinante de todos sea el denominado como equilibrio dinámico y que aparece por primera vez en esta obra . Este término logra verbalizar algo que estaba en el aire, orbitando alrededor de toda la plástica moderna, pero que hasta el momento sólo había sido explicado de forma empírica.En Colin Rowe reverbera la lectura reciente de las ideas kepesianas cuando escribe sus artículos Transparencia literal y fenomenal y Neo-“clasicismo” y arquitectura moderna I y II tratando de poner en evidencia los principios fundacionales del movimiento moderno que negaban la dimensión plástica de la disciplina . El artículo tratará sacar de a la luz y explicar esta influencia. AbstractIn 1944 Gyorgy Kepes published what undoubtless will be his most influential text, "The language of vision". What Kepes tried to do was a guide of grammar and syntax of vision, which allows to face art as purely sensory experience or just visual, devisted of any literary , semantic or sentimental meaning.Among all the concepts that Kepes developes in his essay perhaps the most decisive one is the so called dynamic equilibrium, which is introduced in this work for fi rst time, verbalizing something that was in the air, orbiting around the entire modern plastic but far only explained in an empirical way.Colin Rowe reverberates the recent readed kepesian ideas on his own writings Transparency: Literal and Phenomenal and Neo-'Classicism' and Modern Architecture I and II, when the author tries to highlight the founding

  16. PET/CT Artifacts

    OpenAIRE

    Blodgett, Todd M.; Mehta, Ajeet S.; Mehta, Amar S.; Laymon, Charles M; Carney, Jonathan; Townsend, David W.

    2011-01-01

    There are several artifacts encountered in PET/CT imaging, including attenuation correction (AC) artifacts associated with using CT for attenuation correction. Several artifacts can mimic a 2-deoxy-2-[18F] fluoro-D-glucose (FDG) avid malignant lesions and therefore recognition of these artifacts is clinically relevant. Our goal was to identify and characterize these artifacts and also discuss some protocol variables that may affect image quality in PET/CT.

  17. Emergencies in the retroperitoneum: assessment of spread of disease by helical CT

    Energy Technology Data Exchange (ETDEWEB)

    Scialpi, M. E-mail: michelescialpi@libero.it; Scaglione, M.; Angelelli, G.; Lupattelli, L.; Resta, M.C.; Resta, M.; Rotondo, A

    2004-04-01

    Acute pancreatitis, leaking abdominal aortic aneurysm, and renal trauma frequently occur in the setting of patients with abdominal nontraumatic and traumatic injury; it represents the most urgent conditions that may determine the presence of fluid collections or haematoma in the retroperitoneum. Single spiral CT and multidetector-row CT (MDCT) play an important role in diagnosis of retroperitoneal emergencies, providing useful informations on the type, site, extent and management of the fluid collections. An accurate CT assessment requires the awareness of the existence of dissectable retroperitoneal fascial planes. Fluid collections or haematoma tends to escape the retroperitoneal site of origin into planes extend from the diaphragm to the pelvic floor. We assess the multicompartimental anatomy of the retroperitoneum and the pathway of spread of the most frequent retroperitoneal fluid collections or haematoma by helical CT.

  18. Evaluation of an autonomous GPS-based system for intra-row weed control by assessing the tilled area

    DEFF Research Database (Denmark)

    Nørremark, Michael; Griepentrog, Hans W.; Nielsen, Jon;

    2012-01-01

    -1 and at even plant spacing. A double pass, once on each side of the row in opposite directions, provided higher soil disturbance intensity and resulted in tillage of 31–58% of the intra-row area with highest coverage at a speed of 0.32 m s-1. The intra-row weed control effect was predicted to be up...

  19. Static and dynamic loads on the bottom row of armour units: A theoretical and physical model study

    NARCIS (Netherlands)

    Van de Koppel, M.A.; Muilwijk, M.; Verhagen, H.J.

    2012-01-01

    A physical model study on the row averaged static and dynamic load on the bottom row of single layer armour units in order to investigate the influence of various parameters such as the number of rows on the slope of a breakwater and the initial relative packing density.

  20. 78 FR 25572 - Special Local Regulation; Wy-Hi Rowing Regatta, Trenton Channel; Detroit River, Wyandotte, MI

    Science.gov (United States)

    2013-05-02

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation; Wy-Hi Rowing Regatta, Trenton... navigable waters immediately prior to, during, and immediately after the Wy-Hi Rowing Regatta. This special... to read as follows: Sec. 100.T09-0287 Special Local Regulation; Wy-Hi Rowing Regatta, Wyandotte,...

  1. 77 FR 25077 - Special Local Regulation; Wy-Hi Rowing Regatta, Trenton Channel; Detroit River, Wyandotte, MI

    Science.gov (United States)

    2012-04-27

    ... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation; Wy-Hi Rowing Regatta, Trenton... navigable waters immediately prior to, during, and immediately after the Wy-Hi Rowing Regatta. This special....35T09-0342 Special Local Regulation; Wy-Hi Rowing Regatta, Wyandotte, MI. (a) Regulated Area....

  2. Static and dynamic loads on the bottom row of armour units: A theoretical and physical model study

    NARCIS (Netherlands)

    Van de Koppel, M.A.; Muilwijk, M.; Verhagen, H.J.

    2012-01-01

    A physical model study on the row averaged static and dynamic load on the bottom row of single layer armour units in order to investigate the influence of various parameters such as the number of rows on the slope of a breakwater and the initial relative packing density.

  3. Stiffness matrix formulation for double row angular contact ball bearings: Analytical development and validation

    Science.gov (United States)

    Gunduz, Aydin; Singh, Rajendra

    2013-10-01

    Though double row angular contact ball bearings are widely used in industrial, automotive, and aircraft applications, the scientific literature on double row bearings is sparse. It is also shown that the stiffness matrices of two single row bearings may not be simply superposed to obtain the stiffness matrix of a double row bearing. To overcome the deficiency in the literature, a new, comprehensive, analytical approach is proposed based on the Hertzian theory for back-to-back, face-to-face, and tandem arrangements. The elements of the five-dimensional stiffness matrix for double row angular contact ball bearings are computed given either the mean bearing displacement or the mean load vector. The diagonal elements of the proposed stiffness matrix are verified with a commercial code for all arrangements under three loading scenarios. Some changes in stiffness coefficients are investigated by varying critical kinematic and geometric parameters to provide more insight. Finally, the calculated natural frequencies of a shaft-bearing experiment are successfully compared with measurements, thus validating the proposed stiffness formulation. For double row angular contact ball bearings, the moment stiffness and cross-coupling stiffness terms are significant, and the contact angle changes under loads. The proposed formulation is also valid for paired (duplex) bearings which behave as an integrated double row unit when the surrounding structural elements are sufficiently rigid.

  4. The Effect of Row Structure on Soil Moisture Retrieval Accuracy from Passive Microwave Data

    Directory of Open Access Journals (Sweden)

    Zheng Xingming

    2014-01-01

    Full Text Available Row structure causes the anisotropy of microwave brightness temperature (TB of soil surface, and it also can affect soil moisture retrieval accuracy when its influence is ignored in the inversion model. To study the effect of typical row structure on the retrieved soil moisture and evaluate if there is a need to introduce this effect into the inversion model, two ground-based experiments were carried out in 2011. Based on the observed C-band TB, field soil and vegetation parameters, row structure rough surface assumption (Qp model and discrete model, including the effect of row structure, and flat rough surface assumption (Qp model, ignoring the effect of row structure, are used to model microwave TB of soil surface. Then, soil moisture can be retrieved, respectively, by minimizing the difference of the measured and modeled TB. The results show that soil moisture retrieval accuracy based on the row structure rough surface assumption is approximately 0.02 cm3/cm3 better than the flat rough surface assumption for vegetated soil, as well as 0.015 cm3/cm3 better for bare and wet soil. This result indicates that the effect of row structure cannot be ignored for accurately retrieving soil moisture of farmland surface when C-band is used.

  5. Arthroscopic double-row suture anchor fixation of minimally displaced greater tuberosity fractures.

    Science.gov (United States)

    Ji, Jong-Hun; Kim, Weon-Yoo; Ra, Ki-Hang

    2007-10-01

    In cases of displaced greater tuberosity fractures, treatments by arthroscopic-assisted reduction and percutaneous screw fixation have been reported. However, in cases in which there is a comminuted fracture or a minimally displaced fracture combined with concomitant lesions such as rotator cuff tear or labral pathology, it is difficult to reduce the fracture and to treat other pathologies by use of a percutaneous screw. Recently, many surgeons have used the double-row repair method in rotator cuff repair, which provides a tendon-bone interface better suited for biologic healing and restoring normal anatomy. In accordance with this method, we used the arthroscopic technique of double-row suture anchor fixation for a minimally displaced greater tuberosity fracture without additional incision. Initially, debridement was performed on the fracture surface by use of a shaver, and the medial-row anchor was inserted through the anterior portal or the intact cuff. Two lateral-row anchors were inserted just anterior and posterior to the lower margin of the fractured fragment under C-arm guidance. The medial-row sutures and lateral-row sutures were then placed. Arthroscopic double-row suture anchor fixation of a displaced greater tuberosity fracture restores the original footprint of the rotator cuff and normal tendon-bone interface of the displaced greater tuberosity fracture.

  6. The effect of row structure on soil moisture retrieval accuracy from passive microwave data.

    Science.gov (United States)

    Xingming, Zheng; Kai, Zhao; Yangyang, Li; Jianhua, Ren; Yanling, Ding

    2014-01-01

    Row structure causes the anisotropy of microwave brightness temperature (TB) of soil surface, and it also can affect soil moisture retrieval accuracy when its influence is ignored in the inversion model. To study the effect of typical row structure on the retrieved soil moisture and evaluate if there is a need to introduce this effect into the inversion model, two ground-based experiments were carried out in 2011. Based on the observed C-band TB, field soil and vegetation parameters, row structure rough surface assumption (Q p model and discrete model), including the effect of row structure, and flat rough surface assumption (Q p model), ignoring the effect of row structure, are used to model microwave TB of soil surface. Then, soil moisture can be retrieved, respectively, by minimizing the difference of the measured and modeled TB. The results show that soil moisture retrieval accuracy based on the row structure rough surface assumption is approximately 0.02 cm(3)/cm(3) better than the flat rough surface assumption for vegetated soil, as well as 0.015 cm(3)/cm(3) better for bare and wet soil. This result indicates that the effect of row structure cannot be ignored for accurately retrieving soil moisture of farmland surface when C-band is used.

  7. Validity of blood flow measurement using 320 multi-detectors CT and first-pass distribution theory: a phantom study

    Science.gov (United States)

    Chen, Jun; Yu, Xuefang; Xu, Shaopeng; Zhou, Kenneth J.

    2015-03-01

    To evaluate the feasibility of measuring the myocardial blood flow using 320 row detector CT by first-pass technique. Heart was simulated with a container that was filled with pipeline of 3mm diameter; coronary artery was simulated with a pipeline of 2 cm diameter and connected with the simulated heart. The simulated coronary artery was connected with a big container with 1500 ml saline and 150ml contrast agent. One pump linking with simulated heart will withdraw with a speed of 10 ml/min, 15 ml/min, 20 ml/min, 25 ml/min and 30 ml/min. First CT scan starts after 30 s of pumpback with certain speed. The second CT scan starts 5 s after first CT scans. CT images processed as follows: The second CT scan images subtract first CT scan images, calculate the increase of CT value of simulated heart and the CT value of the unit volume of simulated coronary artery and then to calculate the total inflow of myocardial blood flow. CT myocardial blood flows were calculated as: 0.94 ml/s, 2.09 ml/s, 2.74 ml/s, 4.18 ml/s, 4.86 ml/s. The correlation coefficient is 0.994 and r2 = 0.97. The method of measuring the myocardial blood flow using 320 row detector CT by 2 scans is feasible. It is possible to develop a new method for quantitatively and functional assessment of myocardial perfusion blood flow with less radiation does.

  8. Dynamic blade row compression component model for stability studies

    Science.gov (United States)

    Tesch, W. A.; Steenken, W. G.

    1976-01-01

    This paper describes a generalized dynamic model which has been developed for use in compression component aerodynamic stability studies. The model is a one-dimensional, pitch-line, blade row, lumped volume system. Arbitrary placement of blade free volumes upstream, within, and downstream of the compression component as well as the removal of bleed flow from the exit of any rotor or stator are model options. The model has been applied to a two-stage fan and an eight-stage compressor. The clean inlet pressure ratio/flow maps and the surge line have been reproduced, thereby validating the capability of the dynamic model to reproduce the steady-flow characteristics of the compression component. A method for determining the onset of an aerodynamic instability which is associated with surge is described. Sinusoidally time-varying inlet and exit boundary conditions have been applied to the eight stage compressor as examples of the manner in which this model may be used for stability studies.

  9. Numerical investigation of flow past a row of rectangular rods

    Directory of Open Access Journals (Sweden)

    S.Ul. Islam

    2016-09-01

    Full Text Available A numerical study of uniform flow past a row of rectangular rods with aspect ratio defined as R = width/height = 0.5 is performed using the Lattice Boltzmann method. For this study the Reynolds number (Re is fixed at 150, while spacings between the rods (g are taken in the range from 1 to 6. Depending on g, the flow is classified into four patterns: flip-flopping, nearly unsteady-inphase, modulated inphase-antiphase non-synchronized and synchronized. Sudden jumps in physical parameters were observed, attaining either maximum or minimum values, with the change in flow patterns. The mean drag coefficient (Cdmean of middle rod is higher than the second and fourth rod for flip-flopping pattern while in case of nearly unsteady-inphase the middle rod attains minimum drag coefficient. It is also found that the Strouhal number (St of first, second and fifth rod decreases as g increases while that of other two have mixed trend. The results further show that there exist secondary interaction frequencies together with primary vortex shedding frequency due to jet in the gap between rods for 1 ⩽ g ⩽ 3. For the average values of Cdmean and St, an empirical relation is also given as a function of gap spacing. This relation shows that the average values of Cdmean and St approach to those of single rectangular rod with increment in g.

  10. Mechanical efficiency of the elbow flexors in rowing.

    Science.gov (United States)

    Bompa, T O; Borms, J; Hebbelinck, M

    1990-06-01

    Biomechanical and especially kinesiological investigations of the mechanical efficiency of rowers are rarely found in today's literature. The coach frequently relates to skills or technical movements in terms of their aesthetic appearance rather than their mechanical effectiveness. The force output of the elbow flexors appears to be a function of the forearm position. The literature referring to the mechanical efficiency of the elbow flexors seems to favor both semiprone and supine positions, whereas the prone position appears to be discredited. It is the latter grip position that is actually employed and traditionally accepted in the sport of rowing. In fact, this technique was never challenged or scientifically researched to see whether a modified one might lead to better efficiency. Consequently, the purpose of this investigation was to analyze whether athletes' force output differed if the gripping technique was changed from pronation to a semiprone grip (one arm prone, the other semiprone). Under the specific conditions of this investigation, it was demonstrated that the semiprone position was generating greater force output and higher electrical activity, thus being superior to the classical prone grip.

  11. Characterization of Genome-Wide Variation in Four-Row Wax, a Waxy Maize Landrace with a Reduced Kernel Row Phenotype.

    Science.gov (United States)

    Liu, Hanmei; Wang, Xuewen; Wei, Bin; Wang, Yongbin; Liu, Yinghong; Zhang, Junjie; Hu, Yufeng; Yu, Guowu; Li, Jian; Xu, Zhanbin; Huang, Yubi

    2016-01-01

    In southwest China, some maize landraces have long been isolated geographically, and have phenotypes that differ from those of widely grown cultivars. These landraces may harbor rich genetic variation responsible for those phenotypes. Four-row Wax is one such landrace, with four rows of kernels on the cob. We resequenced the genome of Four-row Wax, obtaining 50.46 Gb sequence at 21.87× coverage, then identified and characterized 3,252,194 SNPs, 213,181 short InDels (1-5 bp) and 39,631 structural variations (greater than 5 bp). Of those, 312,511 (9.6%) SNPs were novel compared to the most detailed haplotype map (HapMap) SNP database of maize. Characterization of variations in reported kernel row number (KRN) related genes and KRN QTL regions revealed potential causal mutations in fea2, td1, kn1, and te1. Genome-wide comparisons revealed abundant genetic variations in Four-row Wax, which may be associated with environmental adaptation. The sequence and SNP variations described here enrich genetic resources of maize, and provide guidance into study of seed numbers for crop yield improvement.

  12. Characterization of genome-wide variation in Four-row Wax, a waxy maize landrace with a reduced kernel row phenotype

    Directory of Open Access Journals (Sweden)

    Hanmei eLiu

    2016-05-01

    Full Text Available In southwest China, some maize landraces have long been isolated geographically, and have phenotypes that differ from those of widely grown cultivars. These landraces may harbor rich genetic variation responsible for those phenotypes. Four-row Wax is one such landrace, with four rows of kernels on the cob. We resequenced the genome of Four-row Wax, obtaining 50.46 Gb sequence at 21.87× coverage, then identified and characterized 3,252,194 SNPs, 213,181 short InDels (1-5 bp and 39,631 structural variations (greater than 5 bp. Of those, 312,511 (9.6% of SNPs were novel compared to the most detailed haplotype map (HapMap SNP database of maize. Characterization of variations in reported kernel row number (KRN related genes and KRN QTL regions revealed potential causal mutations in fea2, td1, kn1 and te1. Genome-wide comparisons revealed abundant genetic variations in Four-row Wax, which may be associated with environmental adaptation. The sequence and SNP variations described here enrich genetic resources of maize, and provide guidance into study of seed numbers for crop yield improvement.

  13. Monitoring of smoking-induced emphysema with CT in a lung cancer screening setting : Detection of real increase in extent of emphysema

    NARCIS (Netherlands)

    Gietema, Hester A.; Schilham, Arnold M.; van Ginneken, Bram; van Klaveren, Rob J.; Lammers, Jan Willem J.; Prokop, Mathias

    2007-01-01

    Purose: To retrospectively establish the minimum increase in emphysema score (ES) required for detection of real Increased extent of emphysema with 95% confidence by using multi-detector row computed tomography (CT) in a lung cancer screening setting. Materials and Methods The study was a substudy o

  14. Single-row vs. double-row arthroscopic rotator cuff repair: clinical and 3 Tesla MR arthrography results.

    Science.gov (United States)

    Tudisco, Cosimo; Bisicchia, Salvatore; Savarese, Eugenio; Fiori, Roberto; Bartolucci, Dario A; Masala, Salvatore; Simonetti, Giovanni

    2013-01-27

    Arthroscopic rotator cuff repair has become popular in the last few years because it avoids large skin incisions and deltoid detachment and dysfunction. Earlier arthroscopic single-row (SR) repair methods achieved only partial restoration of the original footprint of the tendons of the rotator cuff, while double-row (DR) repair methods presented many biomechanical advantages and higher rates of tendon-to-bone healing. However, DR repair failed to demonstrate better clinical results than SR repair in clinical trials. MR imaging at 3 Tesla, especially with intra-articular contrast medium (MRA), showed a better diagnostic performance than 1.5 Tesla in the musculoskeletal setting. The objective of this study was to retrospectively evaluate the clinical and 3 Tesla MRA results in two groups of patients operated on for a medium-sized full-thickness rotator cuff tear with two different techniques. The first group consisted of 20 patients operated on with the SR technique; the second group consisted of 20 patients operated on with the DR technique. All patients were evaluated at a minimum of 3 years after surgery. The primary end point was the re-tear rate at 3 Tesla MRA. The secondary end points were the Constant-Murley Scale (CMS), the Simple Shoulder Test (SST) scores, surgical time and implant expense. The mean follow-up was 40 months in the SR group and 38.9 months in the DR group. The mean postoperative CMS was 70 in the SR group and 68 in the DR group. The mean SST score was 9.4 in the SR group and 10.1 in the DR group. The re-tear rate was 60% in the SR group and 25% in the DR group. Leakage of the contrast medium was observed in all patients. To the best of our knowledge, this is the first report on 3 Tesla MRA in the evaluation of two different techniques of rotator cuff repair. DR repair resulted in a statistically significant lower re-tear rate, with longer surgical time and higher implant expense, despite no difference in clinical outcomes. We think that

  15. Single-row vs. double-row arthroscopic rotator cuff repair: clinical and 3 Tesla MR arthrography results

    Directory of Open Access Journals (Sweden)

    Tudisco Cosimo

    2013-01-01

    Full Text Available Abstract Background Arthroscopic rotator cuff repair has become popular in the last few years because it avoids large skin incisions and deltoid detachment and dysfunction. Earlier arthroscopic single-row (SR repair methods achieved only partial restoration of the original footprint of the tendons of the rotator cuff, while double-row (DR repair methods presented many biomechanical advantages and higher rates of tendon-to-bone healing. However, DR repair failed to demonstrate better clinical results than SR repair in clinical trials. MR imaging at 3 Tesla, especially with intra-articular contrast medium (MRA, showed a better diagnostic performance than 1.5 Tesla in the musculoskeletal setting. The objective of this study was to retrospectively evaluate the clinical and 3 Tesla MRA results in two groups of patients operated on for a medium-sized full-thickness rotator cuff tear with two different techniques. Methods The first group consisted of 20 patients operated on with the SR technique; the second group consisted of 20 patients operated on with the DR technique. All patients were evaluated at a minimum of 3 years after surgery. The primary end point was the re-tear rate at 3 Tesla MRA. The secondary end points were the Constant-Murley Scale (CMS, the Simple Shoulder Test (SST scores, surgical time and implant expense. Results The mean follow-up was 40 months in the SR group and 38.9 months in the DR group. The mean postoperative CMS was 70 in the SR group and 68 in the DR group. The mean SST score was 9.4 in the SR group and 10.1 in the DR group. The re-tear rate was 60% in the SR group and 25% in the DR group. Leakage of the contrast medium was observed in all patients. Conclusions To the best of our knowledge, this is the first report on 3 Tesla MRA in the evaluation of two different techniques of rotator cuff repair. DR repair resulted in a statistically significant lower re-tear rate, with longer surgical time and higher implant

  16. [CT coronary angiography: indications, image acquisition, and interpretation].

    Science.gov (United States)

    Schoepf, U J; Thilo, C; Fernández, M J; Costello, P

    2008-01-01

    Intense scientific and clinical evaluation have brought about great improvements in cardiac CT. This is no longer merely an experimental technique, rather it has become a clinical application that is ready to fulfill its promise of replacing invasive cardiac catheterization in certain patient populations. Among the proven indications is the evaluation of patients with atypical chest pain, the morphological evaluation of the coronary arteries in cases of suspected congenital anomalies, and before surgical intervention, as well as the evaluation of coronary revascularizations. The use of CT angiography for the exhaustive evaluation of cardiac and non-cardiac pathology in patients with acute chest pain in the emergency department is currently being investigated. Because the heart is continuously moving, CT coronary angiography represents a greater technical challenge than other applications of CT. On the other hand, rapid technical development requires acquisition protocols to be adjusted constantly. However, users that know the general techniques of computed tomography can overcome these challenges. The aim of this article is to provide those interested and involved in CT angiography with a manual to enable them to follow our method step by step. We include considerations regarding the correct selection of patients, patient medication, radiological protection, contrast enhancement, acquisition and reconstruction parameters, image display, image analysis techniques, and the radiological report. Our recommendations are based on our experience, which runs from the evolution of multiple-row detector CT scanners for cardiac applications from its beginnings to the most modern presentations of advanced acquisition modalities, including dual-source CT, which we consider to be the precursor of this test in routine clinical practice.

  17. Rowing, the ultimate challenge to the human body - implications for physiological variables

    DEFF Research Database (Denmark)

    Volianitis, S.; Secher, Niels H.

    2009-01-01

    Clinical diagnoses depend on a variety of physiological variables but the full range of these variables is seldom known. With the load placed on the human body during competitive rowing, the physiological range for several variables is illustrated. The extreme work produced during rowing...... is explained by the seated position and the associated ability to increase venous return and, thus, cardiac output. This review highlights experimental work on Olympic rowing that presents a unique challenge to the human capacities, including cerebral metabolism, to unprecedented limits, and provides a unique...

  18. Robotic intra-row weed hoeing in maize and sugar beet

    Directory of Open Access Journals (Sweden)

    Gerhards, Roland

    2016-02-01

    Full Text Available A prototype of robotic intra-row weed hoeing in maize and sugar beet is presented in this study. Weeds in the crop rows were identified using a bi-spectral image analysis system and shape analysis. Positions of weeds in the images were recorded. Selective weed control in the row was performed with a modified finger weeder driven by electrical motors. Speed of the finger weeder was increased at positions where only weeds were classified. The system was triggered by an encoder and controlled by a micro-controller.

  19. CT of Gastric Emergencies.

    Science.gov (United States)

    Guniganti, Preethi; Bradenham, Courtney H; Raptis, Constantine; Menias, Christine O; Mellnick, Vincent M

    2015-01-01

    Abdominal pain, nausea, and vomiting are common presenting symptoms among adult patients seeking care in the emergency department, and, with the increased use of computed tomography (CT) to image patients with these complaints, radiologists will more frequently encounter a variety of emergent gastric pathologic conditions on CT studies. Familiarity with the CT appearance of emergent gastric conditions is important, as the clinical presentation is often nonspecific and the radiologist may be the first to recognize gastric disease as the cause of a patient's symptoms. Although endoscopy and barium fluoroscopy remain important tools for evaluating patients with suspected gastric disease in the outpatient setting, compared with CT these modalities enable less comprehensive evaluation of patients with nonspecific complaints and are less readily available in the acute setting. Endoscopy is also more invasive than CT and has greater potential risks. Although the mucosal detail of CT is relatively poor compared with barium fluoroscopy or endoscopy, CT can be used with the appropriate imaging protocols to identify inflammatory conditions of the stomach ranging from gastritis to peptic ulcer disease. In addition, CT can readily demonstrate the various complications of gastric disease, including perforation, obstruction, and hemorrhage, which may direct further clinical, endoscopic, or surgical management. We will review the normal anatomy of the stomach and discuss emergent gastric disease with a focus on the usual clinical presentation, typical imaging appearance, and differentiating features, as well as potential imaging pitfalls.

  20. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... images or pictures of the inside of the body. The cross-sectional images generated during a CT scan can be reformatted ... of data to create two-dimensional cross-sectional images of your body, which are then displayed on a monitor. CT ...

  1. Abdominal and Pelvic CT

    Medline Plus

    Full Text Available ... images or pictures of the inside of the body. The cross-sectional images generated during a CT scan can be reformatted ... of data to create two-dimensional cross-sectional images of your body, which are then displayed on a monitor. CT ...

  2. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... images or pictures of the inside of the body. The cross-sectional images generated during a CT scan can be reformatted ... of data to create two-dimensional cross-sectional images of your body, which are then displayed on a monitor. CT ...

  3. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... the best way to see if treatment is working or if a finding is stable or changed over time. top of page What are the benefits vs. risks? Benefits A CT scan is one of the safest means of studying the sinuses. CT is the most reliable imaging ...

  4. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... you have a hard time staying still, are claustrophobic or have chronic pain, you may find a CT exam to be stressful. The technologist or nurse, under the direction of a physician, may offer you some medication to help you tolerate the CT scanning procedure. If an ...

  5. Computed Tomography (CT) -- Head

    Medline Plus

    Full Text Available ... you have a hard time staying still, are claustrophobic or have chronic pain, you may find a CT exam to be stressful. The technologist or nurse, under the direction of a physician, may offer you some medication to help you tolerate the CT scanning procedure. If an ...

  6. Computed Tomography (CT) -- Head

    Science.gov (United States)

    ... of a stroke. a stroke, especially with a new technique called Perfusion CT. brain tumors. enlarged brain ... be asked to remove hearing aids and removable dental work. Women will be asked to remove bras ... does the equipment look like? The CT scanner is typically a ...

  7. Spreadsheet Calculations for Jets in Crossflow: Opposed Rows of Inline and Staggered Holes and Single and Opposed Rows with Alternating Hole Sizes

    Science.gov (United States)

    Holdeman, James D.; Clisset, James R.; Moder, Jeffrey P.

    2010-01-01

    The primary purpose of this jet-in-crossflow study was to calculate expected results for two configurations for which limited or no experimental results have been published: (1) cases of opposed rows of closely-spaced jets from inline and staggered round holes and (2) rows of jets from alternating large and small round holes. Simulations of these configurations were performed using an Excel (Microsoft Corporation) spreadsheet implementation of a NASA-developed empirical model which had been shown in previous publications to give excellent representations of mean experimental scalar results suggesting that the NASA empirical model for the scalar field could confidently be used to investigate these configurations. The supplemental Excel spreadsheet is posted with the current report on the NASA Glenn Technical Reports Server (http://gltrs.grc.nasa.gov) and can be accessed from the Supplementary Notes section as TM-2010-216100-SUPPL1.xls. Calculations for cases of opposed rows of jets with the orifices on one side shifted show that staggering can improve the mixing, particularly for cases where jets would overpenetrate slightly if the orifices were in an aligned configuration. The jets from the larger holes dominate the mixture fraction for configurations with a row of large holes opposite a row of smaller ones although the jet penetration was about the same. For single and opposed rows with mixed hole sizes, jets from the larger holes penetrated farther. For all cases investigated, the dimensionless variance of the mixture fraction decreased significantly with increasing downstream distance. However, at a given downstream distance, the variation between cases was small.

  8. CT of tracheal agenesis

    Energy Technology Data Exchange (ETDEWEB)

    Strouse, Peter J.; Hernandez, Ramiro J. [C.S. Mott Children' s Hospital, Department of Radiology, Ann Arbor, MI (United States); Newman, Beverley [Children' s Hospital of Pittsburgh, PA (United States). Department of Pediatric Radiology; Afshani, Ehsan [Children' s Hospital of Buffalo, NY (United States). Departments of Radiology and Pediatrics; Bommaraju, Mahesh [Women' s and Children' s Hospital of Buffalo, Division of Neonatology, University Pediatrics Associates, Buffalo, NY (United States)

    2006-09-15

    Tracheal agenesis is a rare and usually lethal anomaly. In the past, opaque contrast medium was injected via the esophagus to demonstrate the anatomy. To demonstrate the utility of helical and multidetector CT in delineating the aberrant anatomy in newborns with tracheal agenesis. Four newborns with tracheal agenesis were identified from three institutions. Imaging studies and medical records were reviewed. Each child was imaged with chest radiography. One child was imaged on a single-detector helical CT scanner and the other three on multidetector scanners. Helical and multidetector CT with 2D and 3D reconstructions clearly delineated the aberrant tracheobronchial and esophageal anatomy in each infant. Minimum intensity projection reformatted CT images were particularly helpful. One infant each had type I and type II tracheal agenesis. Two infants had type III tracheal agenesis. All four infants died. CT is a useful tool for delineating the aberrant anatomy of newborns with tracheal agenesis and thus helps in making rational clinical decisions. (orig.)

  9. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... CT is less sensitive to patient movement than MRI. CT can be performed if you have an implanted medical device of any kind, unlike MRI. CT imaging provides real-time imaging, making it ...

  10. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography (CT) is ... a CT scan. View full size with caption Pediatric Content Some imaging tests and treatments have special ...

  11. Children's (Pediatric) CT (Computed Tomography)

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    Full Text Available ... of page What are some common uses of the procedure? CT is used to help diagnose a ... the CT examination. top of page What does the equipment look like? The CT scanner is typically ...

  12. Children's (Pediatric) CT (Computed Tomography)

    Science.gov (United States)

    ... Physician Resources Professions Site Index A-Z Children's (Pediatric) CT (Computed Tomography) Pediatric computed tomography (CT) is ... a CT scan. View full size with caption Pediatric Content Some imaging tests and treatments have special ...

  13. Children's (Pediatric) CT (Computed Tomography)

    Medline Plus

    Full Text Available ... scanner. top of page How does the procedure work? In many ways, CT scanning is like other ... scanners to obtain multiple slices in a single rotation. These scanners, called "multislice CT" or "multidetector CT," ...

  14. Impact of UV radiation on the physical properties of polypropylene floating row covers

    National Research Council Canada - National Science Library

    rej, Demscaron ar; Dragan, Žnidarčič; Diana, Gregor Svetec

    2011-01-01

    ... and the cheapest form of protected area is agrotextile, which can be laid directly over vegetable crops (row cover). Agrotextiles are nonwovens which are manufactured from textile fibres which are usually...

  15. Railroad Lines, Railroad ROW, Published in 2009, Polk County Assessor's Office.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Railroad Lines dataset as of 2009. It is described as 'Railroad ROW'. Data by this publisher are often provided in State Plane coordinate system; in a Albers...

  16. A NEW DNA BASED APPROACH OF GENERATING KEYDEPENDENT SHIFT ROWS TRANSFORMATION

    Directory of Open Access Journals (Sweden)

    Auday H. Al-Wattar

    2015-01-01

    Full Text Available The use of key-dependent shiftRows can be considered as one of the applied methods for altering the quality of a cryptographic algorithm. This article describes one approach for changing the ShiftRows transformation employed in the algorithm AES. The approach employs methods inspired from DNA processes and structure which depended on the key while the parameters of the created new ShiftRows have characteristics identical to those of the original algorithm AES in addition to increase its resistance against attacks. The proposed new ShiftRows were tested for coefficient correlation for dynamic and static independence between the input and output. The NIST Test Suite tests were used to test the randomness for the block cipher that used the new transformation.

  17. Numerical Study on the Effect of Tube Rows on the Heat Transfer Characteristic of Dimpled Fin

    Directory of Open Access Journals (Sweden)

    Xuehong Wu

    2014-09-01

    Full Text Available The dimpled fin has excellent heat transfer performance and has attracted a lot of attention to apply on the fin and tube heat exchanger. A study presents to investigate the effects of number of tube rows on the air-side heat transfer characteristics of dimpled fin for velocity ranging from 1 to 3 m/s. The Q/ΔP and Q/((ΔP × V are used to evaluate the heat transfer performance of the heat exchanger. The results show that the dimpled arrangement can change the mainstream direction, increase the disturbance, and enhance the heat transfer. With the increase of the number of tube rows, the average Nusselt number decreases and Q/ΔP and Q/((ΔP × V increase gradually. Compared with the multipipe tube rows, the performance of two-row tube is better.

  18. Influence of Intra row spacing on growth and fodder yield of Lablab ...

    African Journals Online (AJOL)

    that 30 cm intra row spacing produced the highest dry matter yield of Lablab ... increasing livestock production in Nigeria is to increase ..... A tropical forage solution to poor quality ruminant diets: A review of Lablab ... Agriculture and Forest.

  19. Passive microwave remote sensing of soil moisture - The effect of tilled row structure

    Science.gov (United States)

    Wang, J. R.; Newton, R. W.; Rouse, J. W., Jr.

    1980-01-01

    The tilled row structure in agricultural fields is one of the important factors affecting observations of microwave emission from such fields. Measurements of this effect were performed with L-band and X-band radiometers mounted on a mobile truck on a bare 40 m x 45 m row tilled field; the soil moisture content during measurements ranged from 10 to 30% by dry weight. Results showed that the variations of the antenna temperatures with incident angle changed with the azimuth angle measured from the row direction. It is found that the observed difference between horizontally and vertically polarized antenna temperatures is due to the change in the local angle of field emission within the antenna field of view caused by the large-scale row structure.

  20. ROWS wave spectral data collected in SAXON-FPN, November 1990

    Science.gov (United States)

    Jackson, F.; Vandemark, D.; Bailey, S.; Vaughn, C.; Hines, D.; Ward, J.; Stewart, K.; Chapron, B.

    1993-01-01

    High-resolution directional wave spectra obtained with the NASA Ku-band radar ocean wave spectrometer (ROWS) on the Naval Research Laboratory P-3 aircraft during SAXON-FPN (SAR and X-Band Ocean Nonlinearities Experiment-Forschungsplattform Nordsee) experiments in the North Sea in November 1990 are presented. This experiment was the first in which the ROWS was operated with its new pc-based high-speed digital data acquisition system.

  1. CT perfusion scanning of the brain in stroke and beyond; Kranielle CT-Perfusion. Beim Schlaganfall und ueber den Schlaganfall hinaus

    Energy Technology Data Exchange (ETDEWEB)

    Riedel, Christian [UKSH Campus Kiel (Germany). Inst. fuer Neuroradiologie

    2011-06-15

    CT perfusion scanning (CTP) allows for quantitative analysis of cerebral blood flow (CBF) and cerebral blood volume (CBV). Until recently, it was only possible to study brain perfusion parameters in a small stack of CT-slices close to the skull base. With the introduction of multidetector CT scanners with 64 and more detector rows it has become possible to assess perfusion of the entire brain. An optimal choice of scanning parameters like the new 'shuttle'-technique combined with a well adapted regimen for contrast administration is required to guarantee reliable perfusion measurements while still keeping the X-ray dose absorbed by the patient at a minimum. With these techniques, CTP is not only an important modality in the work-up of patients suffering from acute ischemic stroke but can also be valuable in other emergency situations such as in prolonged epileptic seizures or to monitor patients with subacute subarachnoid hemorrhage. (orig.)

  2. Effect of seed rate and row spacing in seed production of Festulolium

    DEFF Research Database (Denmark)

    Deleuran, L C; Gislum, R; Boelt, B

    2010-01-01

    in seed yield. No effect of row spacing on seed yield was observed in Paulita. Neither of the two types was affected in seed yield by seed rate. The fact that row spacing in both types can be increased to 24 cm without having a concomitant negative effect on seed yield implies that mechanical weed control......-type festulolium, Paulita, and in a fescue-type festulolium, Hykor. The objectives were to examine the influence of row spacing (12, 24, and 36 cm) and seed rate (8, 12, or 16 kg ha-1) on plant establishment, development, and seed yield. Observations of autumn and spring in-row plant densities indicated...... satisfactory plant establishment in all combinations of seed rate and row spacing. The number of reproductive tillers was in the range from 800 to 2200 m-2 in Paulita and from 500 to 1300 m-2 in Hykor. Row spacing had an effect on the number of reproductive tillers and in both cultivars the highest number...

  3. Double row spacing and drip irrigation as technical options in energy sorghum management

    Directory of Open Access Journals (Sweden)

    Neri Roncucci

    2014-02-01

    Full Text Available The effect of two row spacing configurations and four water supply levels was investigated on sweet and fibre sorghum in Central Italy for two consecutive years. Results highlighted the influence of both irrigation and row spatial configuration on crop productivity. Indeed, several studies have pointed out the positive response of sorghum to irrigation in Mediterranean climate, as in this environment water stress represents one of the main limiting factors on crop productivity. On the other hand, few attempts have been made to explore the role of row spacing on energy sorghum productivity. Results outlined an average increase in sorghum dry biomass yield ranging from +23% to +79% at variable rates of water supply as compared to rainfed control. The positive effect of irrigation was also observed on leaf area index and radiation use efficiency. Moreover, we observed a crop yield increase, from 9% to 20%, under double row spacing compared to the standard planting pattern (i.e. single row spacing. Finally, it was confirmed the efficient use of water by sorghum and the great ability of sorghum to increase its biomass yield in response to increasing volumes of water supplied. Therefore, this work suggests how row spacing configuration and drip irrigation could be feasible technical options to increase sorghum biomass yields in Mediterranean environments. These techniques should be experienced by farmers towards a sustainable intensification of current cropping systems.

  4. Archaeogenetic evidence of ancient nubian barley evolution from six to two-row indicates local adaptation.

    Directory of Open Access Journals (Sweden)

    Sarah A Palmer

    Full Text Available BACKGROUND: Archaeobotanical samples of barley (Hordeum vulgare L. found at Qasr Ibrim display a two-row phenotype that is unique to the region of archaeological sites upriver of the first cataract of the Nile, characterised by the development of distinctive lateral bracts. The phenotype occurs throughout all strata at Qasr Ibrim, which range in age from 3000 to a few hundred years. METHODOLOGY AND FINDINGS: We extracted ancient DNA from barley samples from the entire range of occupancy of the site, and studied the Vrs1 gene responsible for row number in extant barley. Surprisingly, we found a discord between the genotype and phenotype in all samples; all the barley had a genotype consistent with the six-row condition. These results indicate a six-row ancestry for the Qasr Ibrim barley, followed by a reassertion of the two-row condition. Modelling demonstrates that this sequence of evolutionary events requires a strong selection pressure. CONCLUSIONS: The two-row phenotype at Qasr Ibrim is caused by a different mechanism to that in extant barley. The strength of selection required for this mechanism to prevail indicates that the barley became locally adapted in the region in response to a local selection pressure. The consistency of the genotype/phenotype discord over time supports a scenario of adoption of this barley type by successive cultures, rather than the importation of new barley varieties associated with individual cultures.

  5. Prediction of Rowing Ergometer Performance from Functional Anaerobic Power, Strength and Anthropometric Components

    Directory of Open Access Journals (Sweden)

    Akça Firat

    2014-07-01

    Full Text Available The aim of this research was to develop different regression models to predict 2000 m rowing ergometer performance with the use of anthropometric, anaerobic and strength variables and to determine how precisely the prediction models constituted by different variables predict performance, when conducted together in the same equation or individually. 38 male collegiate rowers (20.17 ± 1.22 years participated in this study. Anthropometric, strength, 2000 m maximal rowing ergometer and rowing anaerobic power tests were applied. Multiple linear regression procedures were employed in SPSS 16 to constitute five different regression formulas using a different group of variables. The reliability of the regression models was expressed by R2 and the standard error of estimate (SEE. Relationships of all parameters with performance were investigated through Pearson correlation coefficients. The prediction model using a combination of anaerobic, strength and anthropometric variables was found to be the most reliable equation to predict 2000 m rowing ergometer performance (R2 = 0.92, SEE= 3.11 s. Besides, the equation that used rowing anaerobic and strength test results also provided a reliable prediction (R2 = 0.85, SEE= 4.27 s. As a conclusion, it seems clear that physiological determinants which are affected by anaerobic energy pathways should also get involved in the processes and models used for performance prediction and talent identification in rowing.

  6. The Double-Row Suture Technique: A Better Option for the Treatment of Haglund Syndrome.

    Science.gov (United States)

    Jiang, Yiqiu; Li, Yang; Tao, Tianqi; Li, Wang; Zhang, Kaibin; Gui, Jianchao; Ma, Yong

    2016-01-01

    Purpose. The purpose of this study is to investigate whether double-row suture technique is a better option for the treatment of Haglund syndrome than single-row suture technique regarding the surgical outcomes. Methods. Thirty-two patients with Haglund syndrome were recruited in this study. Patients were divided into Group 1 (treated with single-row suture technique) and Group 2 (treated with double-row suture technique). There were 16 patients in each group. The AOFAS-ankle-hindfoot scale, VISA-A scores, and Arner-Lindholm standard were used to assess the clinical outcomes. The pre- and postoperative X-rays were used to assess the radiological outcome. Results. Both AOFAS-ankle-hindfoot scale score and VISA-A score had varying degrees of improvement in both groups. In latest follow-up assessment, the Arner-Lindholm standard investigation showed there were 7 excellent, 7 good, and 2 bad outcomes in Group 1 and 12 excellent and 4 good outcomes in Group 2. In Group 2 patients, there were no more posterosuperior bony prominence of the calcaneum in post-op X-rays and there were no recurrent cases. The ankle-related scale score was statistically significantly higher in Group 2 than in Group 1 (P = 0.029). Conclusion. The double-row suture technique seems to be a better option to treat Haglund syndrome than single-row suture technique.

  7. The Double-Row Suture Technique: A Better Option for the Treatment of Haglund Syndrome

    Directory of Open Access Journals (Sweden)

    Yiqiu Jiang

    2016-01-01

    Full Text Available Purpose. The purpose of this study is to investigate whether double-row suture technique is a better option for the treatment of Haglund syndrome than single-row suture technique regarding the surgical outcomes. Methods. Thirty-two patients with Haglund syndrome were recruited in this study. Patients were divided into Group 1 (treated with single-row suture technique and Group 2 (treated with double-row suture technique. There were 16 patients in each group. The AOFAS-ankle-hindfoot scale, VISA-A scores, and Arner-Lindholm standard were used to assess the clinical outcomes. The pre- and postoperative X-rays were used to assess the radiological outcome. Results. Both AOFAS-ankle-hindfoot scale score and VISA-A score had varying degrees of improvement in both groups. In latest follow-up assessment, the Arner-Lindholm standard investigation showed there were 7 excellent, 7 good, and 2 bad outcomes in Group 1 and 12 excellent and 4 good outcomes in Group 2. In Group 2 patients, there were no more posterosuperior bony prominence of the calcaneum in post-op X-rays and there were no recurrent cases. The ankle-related scale score was statistically significantly higher in Group 2 than in Group 1 (P=0.029. Conclusion. The double-row suture technique seems to be a better option to treat Haglund syndrome than single-row suture technique.

  8. Influence of foot-stretcher height on rowing technique and performance.

    Science.gov (United States)

    Buckeridge, Erica M; Weinert-Aplin, Robert A; Bull, Anthony M J; McGregor, Alison H

    2016-11-01

    Strength, technique, and coordination are crucial to rowing performance, but external interventions such as foot-stretcher set-up can fine-tune technique and optimise power output. For the same resultant force, raising the height of foot-stretchers on a rowing ergometer theoretically alters the orientation of the resultant force vector in favour of the horizontal component. This study modified foot-stretcher heights and examined their instantaneous effect on foot forces and rowing technique. Ten male participants rowed at four foot-stretcher heights on an ergometer that measured handle force, stroke length, and vertical and horizontal foot forces. Rowers were instrumented with motion sensors to measure ankle, knee, hip, and lumbar-pelvic kinematics. Key resultant effects of increased foot-stretcher heights included progressive reductions in horizontal foot force, stroke length, and pelvis range of motion. Raising foot-stretcher height did not increase the horizontal component of foot force as previously speculated. The reduced ability to anteriorly rotate the pelvis at the front of the stroke may be a key obstacle in gaining benefits from raised foot-stretcher heights. This study shows that small changes in athlete set-up can influence ergometer rowing technique, and rowers must individually fine-tune their foot-stretcher height to optimise power transfer through the rowing stroke on an ergometer.

  9. Row Sampling for Matrix Algorithms via a Non-Commutative Bernstein Bound

    CERN Document Server

    Magdon-Ismail, Malik

    2010-01-01

    We focus the use of \\emph{row sampling} for approximating matrix algorithms. We give applications to matrix multipication; sparse matrix reconstruction; and, \\math{\\ell_2} regression. For a matrix \\math{\\matA\\in\\R^{m\\times d}} which represents \\math{m} points in \\math{d\\ll m} dimensions, all of these tasks can be achieved in \\math{O(md^2)} via the singular value decomposition (SVD). For appropriate row-sampling probabilities (which typically depend on the norms of the rows of the \\math{m\\times d} left singular matrix of \\math{\\matA} (the \\emph{leverage scores}), we give row-sampling algorithms with linear (up to polylog factors) dependence on the stable rank of \\math{\\matA}. This result is achieved through the application of non-commutative Bernstein bounds. We then give, to our knowledge, the first algorithms for computing approximations to the appropriate row-sampling probabilities without going through the SVD of \\math{\\matA}. Thus, these are the first \\math{o(md^2)} algorithms for row-sampling based appro...

  10. Arthroscopic Double-Row Suture Anchor Repair of Acute Posterior Bony Bankart Lesion.

    Science.gov (United States)

    Ly, Justin A; Coleman, Erin M; Kropf, Eric J

    2016-08-01

    The treatment of anterior shoulder instability is well described with various techniques, including arthroscopic double-row repair, an alternative to open stabilization procedures in high-risk groups. The surgical management of posterior instability in high-risk and athletic populations is a less-explored entity. We describe our technique for an all arthroscopic double-row suture anchor repair of a large posterior bony Bankart lesion. We prefer this technique over percutaneous cannulated screw fixation because the double-row suture technique allows for incorporation of capsular plication with bony fixation in an effort to better restore normal anatomy for capsulolabral complex. Double-row repair capsulolabral repair or fixation of the bony Bankart is performed via a suture-bridge technique. Medial row anchors are placed down the glenoid neck and shuttled around the bony fragment and labrum. The lateral-row anchor is placed at the rim of the native glenoid. This repair technique has been shown to increase the surface area for healing and more closely reconstruct the native anatomic capsulolabral complex footprint, improve force distribution, and potentially impart enhanced posterior stability to the glenohumeral joint.

  11. Feasibility and accuracy of coronary imaging in elderly patients using the 64-row multi-detector computed tomography: a correlation study with conventional coronary angiography

    Institute of Scientific and Technical Information of China (English)

    Wei Ling CHAN; Kui Hian SIM; Chee Khoon LIEW; Sze Piaw CHIN; Tiong Kiam ONG; Seyfarth Tobias; Yean Yip FONG; Choon Kiat ANG; Houng Bang LIEW; Rapaee ANNUAR

    2006-01-01

    Background Elderly patients generally have higher occurrence of coronary calcification, increased heart rate and difficulty with prolonged breath-holding. The aim of our study was to investigate the feasibility and accuracy of using 64-row multi-detector computed tomography (MDCT) in the assessment of coronary artery stenoses in elderly patients. Methods One hundred and fifty two patients with suspected or known coronary artery disease were divided into 4 groups according to their age (Group A: 40-49 years,n=34; Group B: 50-59 years, n=57; Group C: 60-69 years, n=48; Group D: 70 years and above; n=13). Coronary CT angiography (CTA) using a 64-row MDCT was performed and the findings were compared with that of conventional coronary angiography (CCA).Using axial images, multi-planar reconstructions (MPR) and maximum intensity projections (MIP), coronary segments of lumen diameter = 1.5mm were analyzed for the presence of significant stenosis (= 50% ). Results Percentages of poor image quality from coronary CTA preventing reliable correlations with CCA were 21%, 14%, 19% and 62% in Groups A to D respectively. Patients in Group D had significantly higher calcium scores compared with the other groups (P<0.001). In patients where CTA images were of acceptable quality, percentages of accurate correlations with CCA were 89.8%, 93.4%, 86.6% and 78.0% for Groups A to D respectively.There were no significant difference in serum creatinine, heart rate and contrast volume between the 4 groups. Conclusions The 64-row MDCT coronary angiography was less accurate and feasible for patients aged 70 years or above due to heavy coronary calcification and inability to perform a satisfactory breath-hold. However, a high diagnostic accuracy with the MDCT is possible in patients aged less than 70 years.

  12. Evaluation of stenosis severity of coronary calcified lesions using transluminal attenuation gradient: clinical application of 320-row volume CT.

    Science.gov (United States)

    Yang, Fengfeng; Dong, Jie; Wang, Wei; Wang, Xiuting; Fu, Xiaojiao; Kumar, Nanda C; Zhang, Tong

    2017-08-01

    The aim of this study was to evaluate the accuracy of transluminal attenuation gradient (TAG) in diagnosing the stenosis degree of difficult lesions to accurately assess the degree of luminal stenosis using coronary computed tomography angiography (CCTA). A total of 130 patients consecutively received CCTA and coronary angiography (CAG). The average transluminal Hounsfield units (HU) of the regions of interest were consecutively measured at an interval of 5 mm from the ostium to the distal level, followed by the calculation of TAG. The diagnostic performance of CCTA, TAG and CCTA+TAG for the stenosis degree of coronary calcified lesions and their reclassification for stenosis degree were analyzed, especially for calcified lesions. Compared with CAG, the TAG in CCTA was consistent with the largest stenosis degree of each blood vessel. TAG improved the accuracy of CCTA in the diagnosis of calcified lesions (Pcoronary calcified lesions were 90.26%, 95.45%, 98.58% and 73.68%. TAG for calcified lesions had moderate sensitivity (86.61%; 95% CI: 81.8-90.5%) and high specificity (91.20%; 95% CI: 84.8-95.5%). In addition, TAG can help to improve the reclassification of CCTA for coronary stenosis degree, especially for calcified lesions (NRI=0.127, P=0.045). TAG can help to improve the diagnostic performance of CCTA for the stenosis degree of lesions, and it may also help to improve the reclassification of the stenosis degree of calcified lesions.

  13. CT scan of choristoma

    Energy Technology Data Exchange (ETDEWEB)

    Moriki, A.; Morimoto, M.; Sada, Y.; Kurisaka, M.; Mori, K.

    1987-02-01

    Choristoma is a rare tumor that occurs in the pituitary gland. The case presented here is a 44-year-old male. A plain CT scan demonstrated a slight high-density mass near the posterior clinoid of the sella turcica, while a moderate and homogeneous enhancing effect and a clear borderline were shown by an enhanced CT scan. A cornal CT scan study showed that the tumor extended from the intrasellar to the suprasellar region. The diagnosis of choristoma was made by means of histology.

  14. Subtraction CT angiography for evaluation of intracranial aneurysms: comparison with conventional CT angiography

    Energy Technology Data Exchange (ETDEWEB)

    Li, Qi; Li, Kewei; Xie, Peng [The First Affiliated Hospital, Chongqing Medical University, Department of Neurology, Chongqing (China); Lv, Fajin; Li, Yongmei; Luo, Tianyou [The First Affiliated Hospital, Chongqing Medical University, Department of Radiology, Chongqing (China)

    2009-09-15

    The purpose of our study was to compare the diagnostic performance of subtraction computed tomography angiography (CTA) with conventional nonsubtracted CTA and digital subtraction angiography (DSA) for the detection of intracranial aneurysms. A total of 76 patients underwent both subtraction CTA and conventional CTA for the detection and therapy planning of suspected intracranial aneurysms. Subtraction and conventional CTA images were independently assessed by two readers in a blinded manner. The possibility of endovascular treatment or surgical clipping was also assessed based on information provided by CT angiograms alone. In 64 patients, 75 aneurysms were present on DSA. On a per-aneurysm basis, the sensitivity of subtraction CTA was 98.6% for reader 1, and 100% for reader 2. However, sensitivity of conventional CTA was 94.6% for reader 1, and 93.3% for reader 2. Therapeutic decisions could be made regarding 63 patients based on information provided by subtraction CTA images. However, conventional CTA provided sufficient information to make this decision for 55 patients. Conventional CTA has limited sensitivity in detecting very small aneurysms as well as aneurysms adjacent to bone. Subtraction CTA performed on a 64-row multidetector CT is an accurate and promising diagnostic tool that seems to be equivalent to 2D DSA for the detection and pretreatment planning of intracranial aneurysms. (orig.)

  15. CT measurement of coronary calcium mass: impact on global cardiac risk assessment

    Energy Technology Data Exchange (ETDEWEB)

    Becker, Christoph R.; Majeed, Amal; Reiser, Maximilian F. [Ludwig-Maximilians-University Hospital Munich, Department of Clinical Radiology, Munich (Germany); Crispin, Alexander [University Hospital Munich, Department of Medical Data Processing, Biometry, and Epidemiology, Munich (Germany); Knez, Andreas; Boekstegers, Peter; Steinbeck, Gerhard [University Hospital Munich, Department of Cardiology, Munich (Germany); Schoepf, U. Joseph [Harvard Medical School, Department of Radiology, Brigham and Women' s Hospital, Boston, MA (United States)

    2005-01-01

    Coronary calcium mass percentiles can be derived from electron beam CT as well as from multidetector-row CT of all manufacturers. Coronary calcium mass may serve as a more individualized substitute for age for cardiac risk stratification. The aim was to investigate the potential impact of CT coronary calcium mass quantification on cardiac risk stratification using an adjusted Framingham score. Standardized coronary calcium mass was determined by multidetector-row CT in a total of 1,473 patients (1,038 male, 435 female). The impact on risk stratification of replacing the traditional Framingham age point score by a point score based on calcium mass relative to age was tested. Any coronary calcium found in males in the age group of 20-34 years and females in the age group of 20-59 years results in an increase of the Framingham score by 9 and 4-7 points, respectively. Only in males 65 years of age and older, none or minimal amounts of coronary calcium decrease the Framingham score by three points. The coronary calcium mass and age-related scoring system may have impact on the reassignment of patients with an intermediate Framingham risk to a lower or higher risk group. (orig.)

  16. Biomechanical Comparison of Arthroscopic Single- and Double-Row Repair Techniques for Acute Bony Bankart Lesions.

    Science.gov (United States)

    Spiegl, Ulrich J; Smith, Sean D; Todd, Jocelyn N; Coatney, Garrett A; Wijdicks, Coen A; Millett, Peter J

    2014-08-01

    Single- and double-row arthroscopic reconstruction techniques for acute bony Bankart lesions have been described in the literature. The double-row fixation technique would provide superior reduction and stability of a simulated bony Bankart lesion at time zero in a cadaveric model compared with the single-row technique. Controlled laboratory study. Testing was performed on 14 matched pairs of glenoids with simulated bony Bankart fractures with a defect width of 25% of the glenoid diameter. Half of the fractures were repaired with a double-row technique, while the contralateral glenoids were repaired with a single-row technique. The quality of fracture reduction was measured with a coordinate measuring machine. To determine the biomechanical stability of the repairs, specimens were preconditioned with 10 sinusoidal cycles between 5 and 25 N at 0.1 Hz and then pulled to failure in the anteromedial direction at a rate of 5 mm/min. Loads at 1 mm and 2 mm of fracture displacement were determined. The double-row technique required significantly higher forces to achieve fracture displacements of 1 mm (mean, 60.6 N; range, 39.0-93.3 N; P = .001) and 2 mm (mean, 94.4 N; range, 43.4-151.2 N; P = .004) than the single-row technique (1 mm: mean, 30.2 N; range, 14.0-54.1 N and 2 mm: mean, 63.7 N; range, 26.6-118.8 N). Significantly reduced fracture displacement was seen after double-row repair for both the unloaded condition (mean, 1.1 mm; range, 0.3-2.4 mm; P = .005) and in response to a 10-N anterior force applied to the defect (mean, 1.6 mm; range, 0.5-2.7 mm; P = .001) compared with single-row repair (unloaded: mean, 2.1 mm; range, 1.3-3.4 mm and loaded: mean, 3.4 mm; range, 1.9-4.7 mm). The double-row fixation technique resulted in improved fracture reduction and superior stability at time zero in this cadaveric model. This information may influence the surgical technique used to treat large osseous Bankart fractures and the postoperative rehabilitation protocols

  17. Computed Tomography (CT) -- Sinuses

    Medline Plus

    Full Text Available ... is done because a potential abnormality needs further evaluation with additional views or a special imaging technique. ... need for exploratory surgery and surgical biopsy. No radiation remains in a patient's body after a CT ...

  18. Computed Tomography (CT) -- Head

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    Full Text Available ... is done because a potential abnormality needs further evaluation with additional views or a special imaging technique. ... need for exploratory surgery and surgical biopsy. No radiation remains in a patient's body after a CT ...

  19. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ... for guiding minimally invasive procedures such as needle biopsies and needle aspirations of many areas of the ...

  20. Computed Tomography (CT) -- Head

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    Full Text Available ... view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ... eliminate the need for exploratory surgery and surgical biopsy. No radiation remains in a patient's body after ...

  1. Abdominal and Pelvic CT

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    Full Text Available ... view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ... for guiding minimally invasive procedures such as needle biopsies and needle aspirations of many areas of the ...

  2. Abdominal and Pelvic CT

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    Full Text Available ... CT scanning procedure. For exams (excluding head and neck) your head will remain outside the hole in ... type your comment or suggestion into the following text box: Comment: E-mail: Area code: Phone no: ...

  3. Abdominal and Pelvic CT

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    Full Text Available ... liver, shows up in shades of gray, and air appears black. With CT scanning, numerous x-ray ... injected into a vein) to help evaluate blood vessels and organs such as the liver, kidneys and ...

  4. Computed Tomography (CT) -- Head

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    Full Text Available ... liver, shows up in shades of gray, and air appears black. With CT scanning, numerous x-ray ... ability to image bone, soft tissue and blood vessels all at the same time. Unlike conventional x- ...

  5. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... is painless, noninvasive and accurate. It’s also the most reliable imaging technique for determining if the sinuses ... CT scan of the sinuses, the patient is most commonly positioned lying flat on the back. The ...

  6. CT Angiography (CTA)

    Science.gov (United States)

    ... during the procedure. Metal objects, including jewelry, eyeglasses, dentures and hairpins, may affect the CT images and ... of the procedure, you may be asked to complete a questionnaire to ensure your safety during this ...

  7. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... visibility of certain tissues or blood vessels. A nurse or technologist will insert an intravenous (IV) line ... CT exam to be stressful. The technologist or nurse, under the direction of a physician, may offer ...

  8. Abdominal and Pelvic CT

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    Full Text Available ... CT exam to be stressful. The technologist or nurse, under the direction of a physician, may offer ... to you, revolve around you during the imaging process. You will be alone in the exam room ...

  9. Computed Tomography (CT) -- Head

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    Full Text Available ... CT exam to be stressful. The technologist or nurse, under the direction of a physician, may offer ... to you, revolve around you during the imaging process. You will be alone in the exam room ...

  10. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... The teddy bear denotes child-specific content. Related Articles and Media Magnetic Resonance Imaging (MRI) - Head Head and Neck Cancer Treatment Radiation Dose in X-Ray and CT ...

  11. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... time staying still, are claustrophobic or have chronic pain, you may find a CT exam to be stressful. The technologist or nurse, under the direction of a physician, may offer ...

  12. Computed Tomography (CT) -- Head

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    Full Text Available ... time staying still, are claustrophobic or have chronic pain, you may find a CT exam to be stressful. The technologist or nurse, under the direction of a physician, may offer ...

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  14. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... hours prior to your exam. Leave jewelry at home and wear loose, comfortable clothing. You may be ... the CT images and should be left at home or removed prior to your exam. You may ...

  15. Computed Tomography (CT) -- Head

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    Full Text Available ... hours prior to your exam. Leave jewelry at home and wear loose, comfortable clothing. You may be ... the CT images and should be left at home or removed prior to your exam. You may ...

  16. Abdominal and Pelvic CT

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    Full Text Available ... hours prior to your exam. Leave jewelry at home and wear loose, comfortable clothing. You may be ... the CT images and should be left at home or removed prior to your exam. You may ...

  17. Abdominal and Pelvic CT

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    Full Text Available ... liver, shows up in shades of gray, and air appears black. With CT scanning, numerous x-ray ... cause blurring of the images and degrade the quality of the examination the same way that it ...

  18. Computed Tomography (CT) -- Head

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    Full Text Available ... liver, shows up in shades of gray, and air appears black. With CT scanning, numerous x-ray ... cause blurring of the images and degrade the quality of the examination the same way that it ...

  19. Abdominal and Pelvic CT

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    Full Text Available ... tomography (CT) scan View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. ...

  20. Computed Tomography (CT) -- Head

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    Full Text Available ... tomography (CT) scan. View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. ...

  1. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... tomography (CT) scan. View full size with caption Pediatric Content Some imaging tests and treatments have special pediatric considerations. The teddy bear denotes child-specific content. ...

  2. Abdominal and Pelvic CT

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    Full Text Available ... Abdomen and Pelvis? What is CT Scanning of the Abdomen/Pelvis? Computed tomography, more commonly known as ... of page What are some common uses of the procedure? This procedure is typically used to help ...

  3. Abdominal and Pelvic CT

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    Full Text Available ... your exam. You should inform your physician of all medications you are taking and if you have ... body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple slices in a ...

  4. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... your exam. You should inform your physician of all medications you are taking and if you have ... body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple slices in a ...

  5. Computed Tomography (CT) -- Head

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    Full Text Available ... your exam. You should inform your physician of all medications you are taking and if you have ... body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple slices in a ...

  6. CT- and MR colonography

    DEFF Research Database (Denmark)

    Achiam, Michael Patrick; Bülow, Steffen; Rosenberg, J

    2002-01-01

    . Lately, CT- and MR colonography have emerged as non-invasive methods for colon imaging. METHODS: At present, CTC and MRC require bowel preparation. However, preliminary studies have been carried out without colon preparation. After the colon has been filled with air or contrast, the patient is scanned....... CONCLUSIONS: With the exponential development in computer processing power, CT- and MR colonography holds the promise for future colon examination with the advantages of non-invasiveness, no need for sedation, and probably no bowel preparation. A major disadvantage, however, is the radiation dose during CT...... colonography. Future developments with the use of "intelligent" computers, better resolution and faster examinations will make CT and/or MR colonography realistic options to replace conventional diagnostic colonoscopy....

  7. Abdominal and Pelvic CT

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    Full Text Available ... or thyroid problems. Any of these conditions may increase the risk of an unusual adverse effect. Women ... view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ...

  8. Computed Tomography (CT) -- Head

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    Full Text Available ... or thyroid problems. Any of these conditions may increase the risk of an unusual adverse effect. The ... view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ...

  9. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... or thyroid problems. Any of these conditions may increase the risk of an unusual adverse effect. Women ... view of the body's interior. Refinements in detector technology allow nearly all CT scanners to obtain multiple ...

  10. Computed Tomography (CT) -- Head

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    Full Text Available ... additional view capabilities. Modern CT scanners are so fast that they can scan through large sections of ... remain still during the exam. Many scanners are fast enough that children can be scanned without sedation. ...

  11. Pediatric CT Scans

    Science.gov (United States)

    The Radiation Epidemiology Branch and collaborators have initiated a retrospective cohort study to evaluate the relationship between radiation exposure from CT scans conducted during childhood and adolescence and the subsequent development of cancer.

  12. Abdominal and Pelvic CT

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    Full Text Available ... or liver cirrhosis. cancers of the liver, kidneys, pancreas, ovaries and bladder as well as lymphoma. kidney ... and organs such as the liver, kidneys and pancreas. When you enter the CT scanner, special light ...

  13. Abdominal and Pelvic CT

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    Full Text Available ... an image on a special electronic image recording plate. Bones appear white on the x-ray; soft ... which are then displayed on a monitor. CT imaging is sometimes compared to looking into a loaf ...

  14. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... an image on a special electronic image recording plate. Bones appear white on the x-ray; soft ... which are then displayed on a monitor. CT imaging is sometimes compared to looking into a loaf ...

  15. Computed Tomography (CT) -- Head

    Science.gov (United States)

    ... an image on a special electronic image recording plate. Bones appear white on the x-ray; soft ... which are then displayed on a monitor. CT imaging is sometimes compared to looking into a loaf ...

  16. Computed Tomography (CT) -- Head

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    Full Text Available ... an image on a special electronic image recording plate. Bones appear white on the x-ray; soft ... which are then displayed on a monitor. CT imaging is sometimes compared to looking into a loaf ...

  17. Abdominal and Pelvic CT

    Science.gov (United States)

    ... an image on a special electronic image recording plate. Bones appear white on the x-ray; soft ... which are then displayed on a monitor. CT imaging is sometimes compared to looking into a loaf ...

  18. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... many types of tissue as well as the lungs, bones, and blood vessels. CT examinations are fast ... of many areas of the body, particularly the lungs, abdomen, pelvis and bones. A diagnosis determined by ...

  19. Abdominal and Pelvic CT

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    Full Text Available ... many types of tissue as well as the lungs, bones, and blood vessels. CT examinations are fast ... of many areas of the body, particularly the lungs, abdomen, pelvis and bones. A diagnosis determined by ...

  20. Abdominal and Pelvic CT

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    Full Text Available ... to arriving. top of page What will I experience during and after the procedure? CT exams are ... at most a minute or two. You may experience a sensation like you have to urinate; however, ...

  1. Computed Tomography (CT) -- Head

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    Full Text Available ... 10 minutes. top of page What will I experience during and after the procedure? CT exams are ... at most a minute or two. You may experience a sensation like you have to urinate; however, ...

  2. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... 10 minutes. top of page What will I experience during and after the procedure? CT exams are ... at most a minute or two. You may experience a sensation like you have to urinate; however, ...

  3. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... cavity. CT scanning is painless, noninvasive and accurate. It’s also the most reliable imaging technique for determining ... parts absorb the x-rays in varying degrees. It is this crucial difference in absorption that allows ...

  4. Computed Tomography (CT) -- Head

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    Full Text Available ... See the Safety page for more information about pregnancy and x-rays. top of page What does ... See the Safety page for more information about pregnancy and x-rays. CT scanning is, in general, ...

  5. Abdominal and Pelvic CT

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    Full Text Available ... See the Safety page for more information about pregnancy and x-rays. top of page What does ... See the Safety page for more information about pregnancy and x-rays. CT scanning is, in general, ...

  6. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... See the Safety page for more information about pregnancy and x-rays. top of page What does ... See the Safety page for more information about pregnancy and x-rays. CT scanning is, in general, ...

  7. Abdominal and Pelvic CT

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    Full Text Available ... Radiation Therapy for Bladder Cancer Radiation Therapy for Colorectal Cancer top of page This page was reviewed on ... GI Tract X-ray (Radiography) - Upper GI Tract Colorectal Cancer Images related to Computed Tomography (CT) - Abdomen and ...

  8. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... rays used in CT scans should have no immediate side effects. Risks There is always a slight ... possible charges you will incur. Web page review process: This Web page is reviewed regularly by a ...

  9. Computed Tomography (CT) -- Head

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    Full Text Available ... rays used in CT scans should have no immediate side effects. Risks There is always a slight ... possible charges you will incur. Web page review process: This Web page is reviewed regularly by a ...

  10. Abdominal and Pelvic CT

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    Full Text Available ... rays used in CT scans should have no immediate side effects. Risks There is always a slight ... possible charges you will incur. Web page review process: This Web page is reviewed regularly by a ...

  11. Computed Tomography (CT) -- Head

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    Full Text Available ... traditional x-rays, particularly of soft tissues and blood vessels. CT scanning provides more detailed information on head injuries, stroke , brain tumors and other brain diseases than ...

  12. Abdominal and Pelvic CT

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    Full Text Available ... tissue as well as the lungs, bones, and blood vessels. CT examinations are fast and simple; in emergency cases, they can reveal internal injuries and bleeding quickly enough to help save lives. ...

  13. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... tissue as well as the lungs, bones, and blood vessels. CT examinations are fast and simple; in emergency cases, they can reveal internal injuries and bleeding quickly enough to help save lives. ...

  14. Abdominal and Pelvic CT

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    Full Text Available ... during the procedure. Metal objects, including jewelry, eyeglasses, dentures and hairpins, may affect the CT images and ... may increase the risk of an unusual adverse effect. Women should always inform their physician and the ...

  15. Computed Tomography (CT) -- Head

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    Full Text Available ... during the procedure. Metal objects, including jewelry, eyeglasses, dentures and hairpins, may affect the CT images and ... may increase the risk of an unusual adverse effect. The radiologist also should know if you have ...

  16. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... during the procedure. Metal objects, including jewelry, eyeglasses, dentures and hairpins, may affect the CT images and ... may increase the risk of an unusual adverse effect. Women should always inform their physician and the ...

  17. Computed Tomography (CT) -- Head

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    Full Text Available ... is reduced. Though the scanning itself causes no pain, there may be some discomfort from having to ... time staying still, are claustrophobic or have chronic pain, you may find a CT exam to be ...

  18. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... is reduced. Though the scanning itself causes no pain, there may be some discomfort from having to ... time staying still, are claustrophobic or have chronic pain, you may find a CT exam to be ...

  19. Abdominal and Pelvic CT

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    Full Text Available ... often used to determine the cause of unexplained pain. CT scanning is fast, painless, noninvasive and accurate. ... help diagnose the cause of abdominal or pelvic pain and diseases of the internal organs, small bowel ...

  20. Computed Tomography (CT) -- Sinuses

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    Full Text Available ... generated during a CT scan can be reformatted in multiple planes, and can even generate three-dimensional ... hours beforehand, as contrast material will be used in your exam. You should inform your physician of ...