scholarly journals Influence of Image Acquisition on Radiation Dose and Image Quality: Full versus Narrow Phase Window Acquisition Using 320 MDCT

2013 ◽  
Vol 2013 ◽  
pp. 1-5 ◽  
Author(s):  
Faisal Khosa ◽  
Atif Khan ◽  
Khurram Nasir ◽  
Waqas Shuaib ◽  
Matthew Budoff ◽  
...  
Keyword(s):  
Image Quality ◽  
Radiation Dose ◽  
Ordinal Scale ◽  
Diagnostic Image Quality ◽  
Dose Length Product ◽  
Diagnostic Image ◽  
Lower Radiation Dose ◽  
Tube Current ◽  
Dose Modulation ◽  
Mean Heart Rate

Purpose. To compare radiation dose and image quality using predefined narrow phase window versus complete phase window with dose modulation during R-R using 320-row MDCTA.Methods. 114 patients underwent coronary CTA study using 320-row MDCT scanner. 87 patients with mean age (61 + 13 years), mean BMI (29 + 6), and mean heart rate (HR) (58 + 7 bpm) were imaged at predefined 66–80% R-R interval and then reconstructed at 75% while 27 patients with mean age (63 + 16 years), mean BMI (28 + 5), and mean HR (57 + 7 bpm) were scanned throughout the complete R-R interval with tube current modulation. The effective dose (ED) was calculated from dose length product (DLP) and conversionk(0.014 mSv/mGy/cm). Image quality was assessed using a three-point ordinal scale (1 = excellent, 2 = good, and 3 = nondiagnostic).Results. Both groups were statistically similar to each other with reference of HR (P=0.59), BMI (P=0.17), and tube current mAs (P=0.68). The median radiation dose was significantly higher in those scanned with complete R-R phase window versus narrow phase window (P<0.0001). Independently of patient and scan parameters, increased phase window was associated with higher radiation dose (P<0.001). Image quality was better among those scanned with narrow phase window versus complete phase window (P<0.0001).Conclusion. Our study supports that good HR control and predefined narrow window acquisition result in lower radiation dose without compromising diagnostic image quality for coronary disease evaluation.

scholarly journals Reducing cranial computed tomography effective radiation dose by 30% using adaptive iterative dose reduction

2016 ◽  
Vol 25 (4) ◽  
pp. 230-234
Author(s):  
Wai-Yung Yu ◽  
Thye Sin Ho ◽  
Henry Ko ◽  
Wai-Yee Chan ◽  
Serene Ong ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Image Quality ◽  
Radiation Dose ◽  
Dose Reduction ◽  
Diagnostic Image Quality ◽  
Radiation Doses ◽  
Effective Radiation Dose ◽  
Diagnostic Image ◽  
Ct Head ◽  
Effective Radiation

Introduction: The use of computed tomography (CT) imaging as a diagnostic modality is increasing rapidly and CT is the dominant contributor to diagnostic medical radiation exposure. The aim of this project was to reduce the effective radiation dose to patients undergoing cranial CT examination, while maintaining diagnostic image quality. Methods: Data from a total of 1003, 132 and 27 patients were examined for three protocols: CT head, CT angiography (CTA), and CT perfusion (CTP), respectively. Following installation of adaptive iterative dose reduction (AIDR) 3D software, tube current was lowered in consecutive cycles, in a stepwise manner and effective radiation doses measured at each step. Results: Baseline effective radiation doses for CT head, CTA and CTP were 1.80, 3.60 and 3.96 mSv, at currents of 300, 280 and 130–150 mA, respectively. Using AIDR 3D and final reduced currents of 160, 190 and 70–100 mA for CT head, CTA and CTP gave effective doses of 1.29, 3.18 and 2.76 mSv, respectively. Conclusion: We demonstrated that satisfactory reductions in the effective radiation dose for CT head (28.3%), CTA (11.6%) and CTP (30.1%) can be achieved without sacrificing diagnostic image quality. We have also shown that iterative reconstruction techniques such as AIDR 3D can be effectively used to help reduce effective radiation dose. The dose reductions were performed within a short period and can be easily achievable, even in busy departments.

scholarly journals Variation in tube voltage for pediatric neck 64VCT: Effect on radiation dose and image quality

PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0259772
Author(s):  
Li-Guo Chen ◽  
Ping-An Wu ◽  
Hsing-Yang Tu ◽  
Ming-Huei Sheu ◽  
Li-Chuan Huang
Keyword(s):  
Image Quality ◽  
Radiation Dose ◽  
Region Of Interest ◽  
Ct Scanner ◽  
Multidetector Row Ct ◽  
Dose Length Product ◽  
Multidetector Row ◽  
Tube Current ◽  
Noise Measurements ◽  
Unpaired Student

Exposure to ionizing radiation can cause cancer, especially in children. In computed tomography (CT), a trade-off exists between the radiation dose and image quality. Few studies have investigated the effect of dose reduction on image quality in pediatric neck CT. We aimed to assess the effect of peak kilovoltage on the radiation dose and image quality in pediatric neck multidetector-row CT. Measurements were made using three phantoms representative of children aged 1, 5, and 10 years, with tube voltages of 80, 100, and 120 kilovoltage peak (kVp); tube current of 10, 40, 80, 120, 150, 200, and 250 mA; and exposure time = 0.5 s (pitch, 0.984:1). Radiation dose estimates were derived from the dose-length product with a 64-multidetector-row CT scanner. Images obtained from the control protocol (120 kVp) were compared with the 80- and 100-kVp protocols. The effective dose (ED) was determined for each protocol and compared with the 120-kVp protocol. Quantitative analysis entailed noise measurements by recording the standard deviation of attenuation for a circular 1-cm2 region of interest placed on homogeneous soft tissue structures in the phantom. The mean noise of the various kVp protocols was compared using the unpaired Student t-test. Reduction of ED was 37.58% and 68.58% for neck CT with 100 kVp and 80 kVp, respectively. The image noise level increased with the decrease in peak kilovoltage. Noise values were higher at 80 kVp at all neck levels, but did not increase at 100 kVp, compared to 120 kVp in the three phantoms. The measured noise difference was the greatest at 80 kVp (absolute increases<2.5 HU). The subjective image quality did not differ among the protocols. Thus, reducing voltage from 120 to 80 kVp for neck CT may achieve ED reduction of 68.58%, without compromising image quality.

Thoracic-abdominal imaging with a novel dual-layer spectral detector CT: intra-individual comparison of image quality and radiation dose with 128-row single-energy acquisition

2018 ◽  
Vol 59 (12) ◽  
pp. 1458-1465 ◽  
Author(s):  
Stefan Haneder ◽  
Florian Siedek ◽  
Jonas Doerner ◽  
Gregor Pahn ◽  
Nils Grosse Hokamp ◽  
...  
Keyword(s):  
Image Quality ◽  
Radiation Dose ◽  
Ct Images ◽  
Ct Image ◽  
Dose Length Product ◽  
Portal Venous Phase ◽  
Ct Dose ◽  
Automatic Tube Current Modulation ◽  
Lower Radiation Dose

Background A novel, multi-energy, dual-layer spectral detector computed tomography (SDCT) is commercially available now with the vendor’s claim that it yields the same or better quality of polychromatic, conventional CT images like modern single-energy CT scanners without any radiation dose penalty. Purpose To intra-individually compare the quality of conventional polychromatic CT images acquired with a dual-layer spectral detector (SDCT) and the latest generation 128-row single-energy-detector (CT128) from the same manufacturer. Material and Methods Fifty patients underwent portal-venous phase, thoracic-abdominal CT scans with the SDCT and prior CT128 imaging. The SDCT scanning protocol was adapted to yield a similar estimated dose length product (DLP) as the CT128. Patient dose optimization by automatic tube current modulation and CT image reconstruction with a state-of-the-art iterative algorithm were identical on both scanners. CT image contrast-to-noise ratio (CNR) was compared between the SDCT and CT128 in different anatomic structures. Image quality and noise were assessed independently by two readers with 5-point-Likert-scales. Volume CT dose index (CTDIvol), and DLP were recorded and normalized to 68 cm acquisition length (DLP68). Results The SDCT yielded higher mean CNR values of 30.0% ± 2.0% (26.4–32.5%) in all anatomic structures ( P < 0.001) and excellent scores for qualitative parameters surpassing the CT128 (all P < 0.0001) with substantial inter-rater agreement (κ ≥ 0.801). Despite adapted scan protocols the SDCT yielded lower values for CTDIvol (–10.1 ± 12.8%), DLP (−13.1 ± 13.9%), and DLP68 (–15.3 ± 16.9%) than the CT128 (all P < 0.0001). Conclusion The SDCT scanner yielded better CT image quality compared to the CT128 and lower radiation dose parameters.

Reduced computed tomography radiation dose in HIV-related pneumonia: effect on diagnostic image quality

2007 ◽  
Vol 31 (3) ◽  
pp. 178-184 ◽  
Author(s):  
Elisa Busi Rizzi ◽  
Vincenzo Schininà ◽  
Francesco Paolo Gentile ◽  
Corrado Bibbolino
Keyword(s):  
Computed Tomography ◽  
Image Quality ◽  
Radiation Dose ◽  
Diagnostic Image Quality ◽  
Diagnostic Image

scholarly journals Effectiveness of low-tube current for reducing radiation dose in cerebral CT perfusion

2021 ◽  
Author(s):  
Chao Tian ◽  
Tian-hao Yang ◽  
Le-jun Fu ◽  
Song Jin
Keyword(s):  
Image Quality ◽  
Radiation Dose ◽  
Cerebral Blood Volume ◽  
Ct Perfusion ◽  
Signal To Noise Ratio ◽  
Mean Transit Time ◽  
Noise Signal ◽  
Maximum Enhancement ◽  
Dose Length Product ◽  
Tube Current

IntroductionObjective: This study aims to investigate the reduction of radiation dose in cerebral CT perfusion by lower low-tube current.Material and methodsTwo hundred patients, who underwent cerebral non-contrast computed tomography (CT) and CT perfusion, were randomized into four groups according to tube current and contrast media (CM) concentration: group A (60 mAs, 320 mgI/ml), group B (60 mAs, 370 mgI/ml), group C (100 mAs, 320 mgI/ml), and group D (100 mAs, 370 mgI/ml). Among these four groups, the CT dose index (CTDIvol), dose length product (DLP) and effective dose (ED) was calculated. The quantitative image comparison included maximum enhancement, noise, signal-to-noise ratio (SNR), cerebral blood volume (CBV), cerebral blood flow (CBF), and mean transit time (MTT) from five regions of interests (ROIs).ResultsRanging from 100 mAs to 60 mAs, groups A and B achieved 40% lower CTDIvol, DLP and ED, when compared with groups C and D. Both the maximum enhancement and noise of all ROIs were higher in groups A and B, when compared to groups C and D (P<0.05). The CBV values were higher in groups B and D, when compared to groups A and C (P<0.05). The image quality (IQ) of each group of perfusion maps met the requirements for imaging diagnosis.ConclusionsThe reduction in tube current from 100 mAs to 60 mAs for cerebral CT perfusion led to a 40% reduction in radiation dose without sacrificing image quality.

scholarly journals Rising utilization of coronary CT angiography across Europe over the last decade: insights from a large prospective European registry

2021 ◽  
Vol 42 (Supplement_1) ◽  
Author(s):  
B Foldyna ◽  
J Uhlig ◽  
T Mayrhofer ◽  
L Natale ◽  
R Vliegenthart ◽  
...  
Keyword(s):  
Image Quality ◽  
Radiation Dose ◽  
High Volume ◽  
Patient Characteristics ◽  
Diagnostic Image Quality ◽  
Quality And Safety ◽  
Diagnostic Image ◽  
Academic Hospitals ◽  
Coronary Syndromes ◽  
Artery Disease

Abstract Background/Introduction The recently updated 2019 ESC guidelines for the diagnosis and management of chronic coronary syndromes endorse the use of coronary computed tomography angiography (CCTA) for exclusion of obstructive coronary artery disease in patients with a low clinical likelihood (Class I, LOE B). Higher demand for CCTA requires broad availability, inevitably involving smaller healthcare providers, such as non-academic hospitals and private practices. Nevertheless, most published data on CCTA image quality and safety rely on exams performed in high-volume academic centers, and little is known about CCTA in non-academic settings. Purpose To investigate the utilization of CCTA across Europe over the last decade, focusing on differences between academic and non-academic centers. Methods We included patients with stable chest pain and suspected coronary artery disease (CAD) who received CCTA and were included in the European Society of Cardiovascular Radiology MR/CT registry 01/2010–01/2020. We compared CT equipment, image quality, radiation dose, the incidence of periprocedural adverse events, patient characteristics, and CCTA findings between academic (high volume university hospitals) and non-academic centers (non-academic hospitals and private practices). Results Overall, 64,317 patients (41.2% women; age 60±13 years) from 212 sites across 19 European countries were included. Academic centers submitted most cases in 2010—2014 (51.6%), whereas non-academic centers accounted for 71.3% of records in 2015–2020. While non-academic centers used less advanced technology, radiation dose remained low (4.54 [interquartile range (IQR) 2.28–6.76] mSv) with a 30% decline of high-dose scans (&gt;7 mSv) over time. Diagnostic image quality was reported in 97.7% of cases, and the rate of acute scan-related events was low (0.4%) (Figure 1). From 2010–2014 to 2015–2020, CCTA nearly doubled in patients with low to intermediate pretest-probability, women &gt;50, and 40–60 years old men (Figure 2). CAD presence and extent decreased slightly over time (prevalence: 2010–2014: 41.5% vs. 2015–2020: 40.6%), (multi-vessel disease in those with CAD: 2010–2014: 61.9% vs. 2015–2020: 55.9%; all p&lt;0.01). Conclusion CCTA expands rapidly to non-academic centers across Europe, increasing availability while maintaining relatively low radiation dose, high diagnostic image quality, and safety. Broad availability of high-quality CCTA is essential for a successfully implementation of the recently updated guidelines for the diagnosis and management of chronic coronary syndromes. FUNDunding Acknowledgement Type of funding sources: None. Changes in CCTA utilization Changes in patient characteristics

scholarly journals Can image enhancement allow radiation dose to be reduced whilst maintaining the perceived diagnostic image quality required for coronary angiography?

2017 ◽  
Vol 90 (1071) ◽  
pp. 20160660
Author(s):  
Anuja Joshi ◽  
Amber J Gislason-Lee ◽  
Claire Keeble ◽  
Uduvil M Sivananthan ◽  
Andrew G Davies
Keyword(s):  
Image Quality ◽  
Radiation Dose ◽  
Coronary Angiography ◽  
Image Enhancement ◽  
Diagnostic Image Quality ◽  
Diagnostic Image

Effect of tube current on diagnostic image quality in paediatric cerebral multidetector CT images

2009 ◽  
Vol 82 (976) ◽  
pp. 313-320 ◽  
Author(s):  
K LEDENIUS ◽  
M GUSTAVSSON ◽  
S JOHANSSON ◽  
F STÅLHAMMAR ◽  
L-M WIKLUND ◽  
...  
Keyword(s):  
Image Quality ◽  
Multidetector Ct ◽  
Ct Images ◽  
Diagnostic Image Quality ◽  
Diagnostic Image ◽  
Tube Current
Sign in / Sign up

Export Citation Format

Share Document