SU-E-I-25: Determining Tube Current, Tube Voltage and Pitch Suitable for Low- Dose Lung Screening CT

2014 ◽  
Vol 41 (6Part5) ◽  
pp. 135-135
Author(s):  
K Williams ◽  
K Matthews
Keyword(s):  
Low Dose ◽  
Tube Voltage ◽  
Current Tube ◽  
Tube Current ◽  
Lung Screening

scholarly journals Repeatability of small lung nodule measurement in low-dose lung screening: a phantom study

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Yu Du ◽  
Gao-Feng Shi ◽  
Ya-Ning Wang ◽  
Qi Wang ◽  
Hui Feng
Keyword(s):  
Lung Cancer ◽  
Cancer Screening ◽  
Low Dose ◽  
Lung Nodule ◽  
Pulmonary Nodules ◽  
Lung Cancer Screening ◽  
Tube Voltage ◽  
Conventional Dose ◽  
Tube Current ◽  
Lung Screening

Abstract Background Lung cancer screening revealed that people with small pulmonary nodules are mostly asymptomatic and that some of these people are at risk of developing lung cancer, so we intended to explore the repeatability of small lung nodule measurement in low-dose lung screening. Methods We scanned eight ground-glass nodules (GGNs) and solid nodules, with diameters of 3, 5, 8, and 10 mm. They were divided according to the different combination schemes of tube voltage (KV) and tube current (mA) as 70, 80, 100, and 120 KV, and currents of nine tubes were divided as 20, 30, 40, 50, 60, 70, 80, 90, and 100 mAs. Results Compared with the conventional dose group (120 kVp, 100 mAs), the nodule diameter and solid nodule volume measured by all scanning combinations were more consistent (P > 0.05), the volumes of 10 mm GGNs combinations were consistent (P > 0.05), the volumes of 8 mm GGNs were consistent (P > 0.05), the volumes of 5 mm GGNs combinations were consistent (P > 0.05), and the volumes of 3 mm were consistent (P > 0.05). Conclusion In lung cancer screening, CT parameters should be as follows: tube voltage is more than 80 kVp, and tube current is 80 mAs in order to meet the requirements for the accurate measurement of the diameter and volume of pulmonary nodules.

scholarly journals Incidental renal tumours on low-dose CT lung cancer screening exams

2016 ◽  
Vol 24 (2) ◽  
pp. 104-109 ◽  
Author(s):  
Paul F Pinsky ◽  
Barbara Dunn ◽  
David Gierada ◽  
P Hrudaya Nath ◽  
Reginald Munden ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Lung Cancer ◽  
Renal Cancer ◽  
Low Dose ◽  
Lung Cancer Screening ◽  
National Lung Screening Trial ◽  
Renal Tumours ◽  
Chest X Ray ◽  
Low Dose Computed Tomography ◽  
Lung Screening

Introduction Renal cancer incidence has increased markedly in the United States in recent decades, largely due to incidentally detected tumours from computed tomography imaging. Here, we analyze the potential for low-dose computed tomography lung cancer screening to detect renal cancer. Methods The National Lung Screening Trial randomized subjects to three annual screens with either low-dose computed tomography or chest X-ray. Eligibility criteria included 30 + pack-years, current smoking or quit within 15 years, and age 55–74. Subjects were followed for seven years. Low-dose computed tomography screening forms collected information on lung cancer and non-lung cancer abnormalities, including abnormalities below the diaphragm. A reader study was performed on a sample of National Lung Screening Trial low-dose computed tomography images assessing presence of abnormalities below the diaphragms and abnormalities suspicious for renal cancer. Results There were 26,722 and 26,732 subjects enrolled in the low-dose computed tomography and chest X-ray arms, respectively, and there were 104 and 85 renal cancer cases diagnosed, respectively (relative risk = 1.22, 95% CI: 0.9–1.5). From 75,126 low-dose computed tomography screens, there were 46 renal cancer diagnoses within one year. Abnormalities below the diaphragm rates were 39.1% in screens with renal cancer versus 4.1% in screens without (P < 0.001). Cases with abnormalities below the diaphragms had shorter median time to diagnosis than those without (71 vs. 160 days, P = 0.004). In the reader study, 64% of renal cancer cases versus 13% of non-cases had abnormalities below the diaphragms; 55% of cases and 0.8% of non-cases had a finding suspicious for renal cancer (P < 0.001). Conclusion Low-dose computed tomography screens can potentially detect renal cancers. The benefits to harms tradeoff of incidental detection of renal tumours on low-dose computed tomography is unknown.

scholarly journals Opportunities to reduce the radiation exposure during computed tomography to assess the changes in the lungs in patients with COVID-19: use of adaptive statistical iterative reconstruction

2021 ◽  
Vol 2 (2) ◽  
pp. 94-104
Author(s):  
Daria A. Filatova ◽  
Valentin E. Sinitsin ◽  
Elena A. Mershina
Keyword(s):  
Image Quality ◽  
Low Dose ◽  
Diagnostic Value ◽  
University Hospital ◽  
State University ◽  
Radiation Load ◽  
Adaptive Statistical Iterative Reconstruction ◽  
Tube Voltage ◽  
Statistical Iterative Reconstruction ◽  
Moscow State University

BACKGROUND: Several COVID-19 patients are subjected to multiple imaging examinations during hospitalization, the cumulative effect of which can significantly increase the total dose of radiation received. The effective radiation dose can be reduced by lowering the current and voltage of the X-ray tube, but this reduces image quality. One possible solution is to use adaptive statistical iterative reconstruction technology on the raw CT data. Recently, data on the efficacy of low-dose CT (LDCT) in the diagnosis of COVID-19 have appeared in the literature. AIM: To analyze the quality and diagnostic value of LDCT images of the lungs after applying an iterative processing algorithm and to assess the possibility of reducing the radiation load on the patient when diagnosing COVID-19. MATERIALS AND METHODS: Patients from the Infectious Diseases Department of the Moscow State University Hospital participated in the prospective study. CT examinations were performed at the time of patient admission and discharge and were repeated as needed during hospitalization. In the first study, a standard CT protocol with a tube voltage of 120 kV and automatic current modulation in the range of 200400 mA was used; in repeated CT scans, the LDKT protocol was used with reduced tube voltage parameters (100 or 110 kV) and automatic current modulation in the range of 40120 mA. To assess the diagnostic value of LDCT in comparison with standard CT, a survey was conducted among doctors from the Department of Radiation Diagnostics at Moscow State University Hospital. The questionnaire included a comparison of the two methods for identifying the following pathological processes: ground-glass opacities, compaction of the lung tissue with reticular changes, areas of lung tissue consolidation, and lymphadenopathy. RESULTS: The study included 151 patients. The average age was 5814.2 years, with men accounting for 53.6% of the population. During LDCT the radiation load was reduced by 2.96 times on average, CTDI by 2.6 times, DLP by 3.1 times, the current on the tube by 1.83 times, and the voltage on the tube by 1.2 times. The results indicate that the effectiveness of detecting the main signs of viral pneumonia and assessing the dynamics of the patients condition does not differ significantly from CT performed according to the standard protocol. CONCLUSIONS: The results of a comparison of standard and low-dose CT show that there is no significant loss of diagnostic information and image quality as the radiation load is reduced. Thus, chest LDCT can be used to successfully diagnose COVID-19 in routine practice.

Low-Dose MDCT Urography: Feasibility Study of Low-Tube-Voltage Technique and Adaptive Noise Reduction Filter

2009 ◽  
Vol 193 (3) ◽  
pp. W220-W229 ◽  
Author(s):  
Yumi Yanaga ◽  
Kazuo Awai ◽  
Yoshinori Funama ◽  
Takeshi Nakaura ◽  
Toshinori Hirai ◽  
...  
Keyword(s):  
Noise Reduction ◽  
Feasibility Study ◽  
Low Dose ◽  
Tube Voltage ◽  
Low Tube Voltage ◽  
Adaptive Noise

Effects of x-ray exposure on NOR and NAND flash memories during high-resolution 2D and 3D x-ray inspection

2016 ◽  
Vol 2016 (1) ◽  
pp. 000660-000665
Author(s):  
Anju Sharma ◽  
Preeth Sivakumar ◽  
Andrew Feigel ◽  
In Tae Bae ◽  
Lawrence P. Lehman ◽  
...  
Keyword(s):  
Exposure Time ◽  
Flash Memory ◽  
Low Energy ◽  
Memory Devices ◽  
Nand Flash ◽  
Flash Memories ◽  
Tube Voltage ◽  
X Ray ◽  
Data Corruption ◽  
Tube Current

Abstract In this paper, we present a detailed study on the effects of x-ray exposure on data corruption in commercially available NOR and NAND flash memory devices during x-ray inspection with a high-resolution Phoenix Nanomex system from GE. We investigated role of the x-ray tube voltage, tube current, device orientation, x-ray filters and photon energy. We explored the low exposure regime in detail when the first byte errors start occurring and also determined the absorbed dose for 100% byte errors. No data corruption was observed after the normal 2D x-ray inspection and CT scans of the NOR and NAND flash memory devices under study. However, increase in the tube voltage, tube current and/or the x-ray beam size resulted in byte errors which increased exponentially with the exposure time. The byte error rate was found to be much more sensitive to the tube voltage than the tube current. It was also affected by the device orientation with respect to the x-ray beam. The NAND flash memories were found to be more susceptible to data corruption from x-ray exposure than the NOR devices examined in this work. Some NOR devices were irradiated with the monochromatic x-rays from the CHESS synchrotron facility at Cornell University. Of all the photon energies used in this study, 12 keV x-ray irradiation resulted in the highest byte error rate. In this paper, we thus present a direct proof that it is the low-energy photon absorption that plays a major role in introducing bit errors in flash memories. Commonly available low-energy x-ray filters such as Cu and Al foils were found to be effective in preventing data corruption in such devices for long exposure time. Use of lower tube voltage, lower tube current, smaller x-ray spot size, short exposure time and low-energy x-ray filters, is recommended to prevent data corruption during 2D and 3D x-ray inspection of flash memory devices and other semiconductor devices in general.

New Rotating Anode X-Ray Generator For XAFS Experiments

1995 ◽  
Vol 39 ◽  
pp. 149-153
Author(s):  
Kenji Sakurai
Keyword(s):  
High Vacuum ◽  
Lanthanum Hexaboride ◽  
X Rays ◽  
Tube Voltage ◽  
X Ray ◽  
Low Tube Voltage ◽  
Tube Current ◽  
Sample Position ◽  
Good Energy ◽  
X Ray Absorption

A high-power X-ray generator equipped with a lanthanum hexaboride cathode has been developed for X-ray absorption fine structure experiments. A high tube-current of more than 1,000 mA can be provided when operated at low tube-voltage of less than 20 kV. In addition, the focal width is narrow enough (less than 0.1 mm) to ensure good energy resolution. Extremely intense monochromatic X-rays (106 ∼ 107 counts/(sec.mm2) at the sample position), which are completely free from higher order harmonics and tungsten contamination lines, are available, when a Johansson-type spectrometer is employed. The filament life has been significantly prolonged by the high vacuum specification of the tube.

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