Radiation dose levels in chest computed tomography scans of coronavirus disease 2019 pneumonia

Objective: The aim of the present study was to evaluate a dose reduction in contrast-enhanced chest computed tomography (CT) by comparing the three latest generations of Siemens CT scanners used in clinical practice. We analyzed the amount of radiation used with filtered back projection (FBP) and an iterative reconstruction (IR) algorithm to yield the same image quality. Furthermore, the influence on the radiation dose of the most recent integrated circuit detector (ICD; Stellar detector, Siemens Healthcare, Erlangen, Germany) was investigated. Materials and Methods: 136 Patients were included. Scan parameters were set to a thorax routine: SOMATOM Sensation 64 (FBP), SOMATOM Definition Flash (IR), and SOMATOM Definition Edge (ICD and IR). Tube current was set constantly to the reference level of 100 mA automated tube current modulation using reference milliamperes. Care kV was used on the Flash and Edge scanner, while tube potential was individually selected between 100 and 140 kVp by the medical technologists at the SOMATOM Sensation. Quality assessment was performed on soft-tissue kernel reconstruction. Dose was represented by the dose length product. Results: Dose-length product (DLP) with FBP for the average chest CT was 308 mGy*cm ± 99.6. In contrast, the DLP for the chest CT with IR algorithm was 196.8 mGy*cm ± 68.8 (P = 0.0001). Further decline in dose can be noted with IR and the ICD: DLP: 166.4 mGy*cm ± 54.5 (P = 0.033). The dose reduction compared to FBP was 36.1% with IR and 45.6% with IR/ICD. Signal-to-noise ratio (SNR) was favorable in the aorta, bone, and soft tissue for IR/ICD in combination compared to FBP (the P values ranged from 0.003 to 0.048). Overall contrast-to-noise ratio (CNR) improved with declining DLP. Conclusion: The most recent technical developments, namely IR in combination with integrated circuit detectors, can significantly lower radiation dose in chest CT examinations.

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Precision of determining bone pose and marker position in the foot and lower leg from computed tomography scans: How low can we go in radiation dose?

Medical Engineering & Physics ◽

10.1016/j.medengphy.2019.05.004 ◽

2019 ◽

Vol 69 ◽

pp. 147-152 ◽

Cited By ~ 1

Author(s):

W. Schallig ◽

J.C. van den Noort ◽

R.P. Kleipool ◽

J.G.G. Dobbe ◽

M.M. van der Krogt ◽

...

Keyword(s):

Computed Tomography ◽

Radiation Dose ◽

Lower Leg ◽

Marker Position ◽

Computed Tomography Scans

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[P033] Evaluation, comparison and optimization of the effects of manual versus software automated protocols on radiation dose and image quality in paediatric chest computed tomography

Physica Medica ◽

10.1016/j.ejmp.2018.06.358 ◽

2018 ◽

Vol 52 ◽

pp. 107-108

Author(s):

Luca Bellesi ◽

Gianluca Argentieri ◽

Filippo Del Grande ◽

Stefano Presilla ◽

Corrado Soldati ◽

...

Keyword(s):

Computed Tomography ◽

Image Quality ◽

Radiation Dose ◽

Chest Computed Tomography

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Indeterminate Pulmonary Nodules at Diagnosis in Rhabdomyosarcoma: Are They Clinically Significant? A Report From the European Paediatric Soft Tissue Sarcoma Study Group

Journal of Clinical Oncology ◽

10.1200/jco.18.01535 ◽

2019 ◽

Vol 37 (9) ◽

pp. 723-730 ◽

Cited By ~ 5

Author(s):

Bas Vaarwerk ◽

Gianni Bisogno ◽

Kieran McHugh ◽

Hervé J. Brisse ◽

Carlo Morosi ◽

...

Keyword(s):

Computed Tomography ◽

Overall Survival ◽

Soft Tissue ◽

Soft Tissue Sarcoma ◽

Pulmonary Nodules ◽

Study Group ◽

Event Free Survival ◽

Free Survival ◽

Chest Computed Tomography ◽

Computed Tomography Scans

Purpose To evaluate the clinical significance of indeterminate pulmonary nodules at diagnosis (defined as ≤ 4 pulmonary nodules < 5 mm or 1 nodule measuring ≥ 5 and < 10 mm) in patients with pediatric rhabdomyosarcoma (RMS). Patients and Methods We selected patients with supposed nonmetastatic RMS treated in large pediatric oncology centers in the United Kingdom, France, Italy, and the Netherlands, who were enrolled in the European Soft Tissue Sarcoma Study Group (E pSSG) RMS 2005 study. Patients included in the current study received a diagnosis between September 2005 and December 2013, and had chest computed tomography scans available for review that were done at time of diagnosis. Local radiologists were asked to review the chest computed tomography scans for the presence of pulmonary nodules and to record their findings on a standardized case report form. In the E pSSG RMS 2005 Study, patients with indeterminate pulmonary nodules were treated identically to patients without pulmonary nodules, enabling us to compare event-free survival and overall survival between groups by log-rank test. Results In total, 316 patients were included; 67 patients (21.2%) had indeterminate pulmonary nodules on imaging and 249 patients (78.8%) had no pulmonary nodules evident at diagnosis. Median follow-up for survivors (n = 258) was 75.1 months; respective 5-year event-free survival and overall survival rates (95% CI) were 77.0% (64.8% to 85.5%) and 82.0% (69.7% to 89.6%) for patients with indeterminate nodules and 73.2% (67.1% to 78.3%) and 80.8% (75.1% to 85.3%) for patients without nodules at diagnosis ( P = .68 and .76, respectively). Conclusion Our study demonstrated that indeterminate pulmonary nodules at diagnosis do not affect outcome in patients with otherwise localized RMS. There is no need to biopsy or upstage patients with RMS who have indeterminate pulmonary nodules at diagnosis.

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Readjustment of abdominal computed tomography protocols in a university hospital: impact on radiation dose

Radiologia Brasileira ◽

10.1590/0100-3984.2014.0054 ◽

2015 ◽

Vol 48 (5) ◽

pp. 292-297 ◽

Cited By ~ 4

Author(s):

Ricardo Francisco Tavares Romano ◽

Priscila Silveira Salvadori ◽

Lucas Rios Torres ◽

Elisa Almeida Sathler Bretas ◽

Daniel Bekhor ◽

...

Keyword(s):

Computed Tomography ◽

Radiation Dose ◽

Clinical Suspicion ◽

University Hospital ◽

Abdominal Ct ◽

Abdominal Computed Tomography ◽

Computed Tomography Scans ◽

Group A ◽

Group B ◽

Tomography Scan

AbstractObjective:To assess the reduction of estimated radiation dose in abdominal computed tomography following the implementation of new scan protocols on the basis of clinical suspicion and of adjusted images acquisition parameters.Materials and Methods:Retrospective and prospective review of reports on radiation dose from abdominal CT scans performed three months before (group A – 551 studies) and three months after (group B – 788 studies) implementation of new scan protocols proposed as a function of clinical indications. Also, the images acquisition parameters were adjusted to reduce the radiation dose at each scan phase. The groups were compared for mean number of acquisition phases, mean CTDIvol per phase, mean DLP per phase, and mean DLP per scan.Results:A significant reduction was observed for group B as regards all the analyzed aspects, as follows: 33.9%, 25.0%, 27.0% and 52.5%, respectively for number of acquisition phases, CTDIvol per phase, DLP per phase and DLP per scan (p < 0.001).Conclusion:The rational use of abdominal computed tomography scan phases based on the clinical suspicion in conjunction with the adjusted images acquisition parameters allows for a 50% reduction in the radiation dose from abdominal computed tomography scans.

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