Development of a computational tool for estimating computed tomography dose parameters

2020 ◽  
Vol 28 (6) ◽  
pp. 1025-1035
Author(s):  
Hussain M. Almohiy ◽  
Khalid I. Hussein ◽  
Mohammed S. Alqahtani ◽  
Mohammad Rawashdeh ◽  
Elhussaien Elshiekh ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Radiation Risk ◽  
Diagnostic Procedures ◽  
Ct Scanner ◽  
Computational Tool ◽  
Computed Tomographic ◽  
Ct Dose ◽  
Ct Radiation ◽  
Ct Head ◽  
Periodic Inspections

BACKGROUND: Computed Tomographic (CT) imaging procedures have been reported as the main source of radiation in diagnostic procedures compared to other modalities. To provide the optimal quality of CT images at the minimum radiation risk to the patient, periodic inspections and calibration tests for CT equipment are required. These tests involve a series of measurements that are time consuming and may require specific skills and highly-trained personnel. OBJECTIVE: This study aims to develop a new computational tool to estimate the dose of CT radiation outputs and assist in the calibration of CT scanners. It may also provide an educational resource by which radiological practitioners can learn the influence of technique factors on both patient radiation dose and the produced image quality. METHODS: The computational tool was developed using MATLAB in order to estimate the CT radiation dose parameters for different technique factors. The CT radiation dose parameters were estimated from the calibrated energy spectrum of the x-ray tube for a CT scanner. RESULTS: The estimated dose parameters and the measured values utilising an Adult CT Head Dose Phantom showed linear correlations for different tube voltages (80 kVp, 100 kVp, 120 kVp, and 140 kVp), with R2 nearly equal to 1 (0.99). The maximum differences between the estimated and measured CTDIvol were under 5 %. For 80 kVp and low tube currents (50 mA, 100 mA), the maximum differences were under 10%. CONCLUSIONS: The prototyped computational model provides a tool for the simulation of a machine-specific spectrum and CT dose parameters using a single dose measurement.

scholarly journals Radiologists’ Knowledge and Attitudes towards CT Radiation Dose and Exposure in Saudi Arabia—A Survey Study

2020 ◽  
Vol 8 (3) ◽  
pp. 27 ◽  
Author(s):  
Hussain M Almohiy ◽  
Khalid Hussein ◽  
Mohammed Alqahtani ◽  
Elhussaien Elshiekh ◽  
Omer Loaz ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Radiation Risk ◽  
Survey Study ◽  
Ct Scans ◽  
Specific Information ◽  
Highly Sensitive ◽  
Key Factor ◽  
Ct Radiation ◽  
Training Courses ◽  
Multiple Choice Questionnaire

Computed tomography (CT) is a key imaging technique in diagnostic radiology, providing highly sensitive and specific information. While its use has increased dramatically in recent years, the quantity and associated risks of radiation from CT scans present major challenges, particularly in paediatrics. The fundamental principles of radiation protection require that radiation quantities be as low as reasonably achievable and CT use must be justified, particularly for paediatric patients. CT radiation knowledge is a key factor in optimising and minimising radiation risk. The objective of this study was to analyse knowledge level, expertise, and competency regarding CT radiation dose and its hazards in paediatrics among radiologists in Saudi Arabian hospitals. A self-reported, multiple-choice questionnaire assessed the attitudes and opinions of radiologists involved in imaging studies using ionising radiation. Among the total respondents, 65% ± 13.5% had a good comprehension of the dangers of carcinogenicity to the patient resulting from CT scans, with 80% presuming that cancer risks were elevated. However, only 48.5%, 56.5%, and 65% of the respondents were aware of specific radiation risks in head, chest, and abdominal paediatric examinations, respectively. Regular, frequent, and specific training courses are suggested to improve the fundamental knowledge of CT radiation among radiologists and other physicians.

scholarly journals Radiation dose from CT scanning: can it be reduced?

2011 ◽  
Vol 5 (1) ◽  
pp. 13-21 ◽  
Author(s):  
Panruethai Trinavarat ◽  
Supika Kritsaneepaiboon ◽  
Chantima Rongviriyapanich ◽  
Pannee Visrutaratna ◽  
Jiraporn Srinakarin
Keyword(s):  
Radiation Dose ◽  
Ct Scan ◽  
Ct Scanning ◽  
Basic Knowledge ◽  
Radiation Doses ◽  
University Hospitals ◽  
Lifetime Cancer Risk ◽  
Ct Dose ◽  
Ct Radiation ◽  
Probability Of Cancer

Abstract CT has been used to save many patients’ lives and the demand for CT is still increasing. At the same time, there has been increasing concern of the probability of cancer induction by CT radiation. It is necessary for everyone involved in CT scanning, particularly physicians who have to communicate with patients when planning a CT scan, to have a basic knowledge of the CT radiation dose and its potential adverse effects. We have undertaken a systematic review of the literatures to document the radiation dose from CT, the lifetime cancer risk from CT exposure, CT dose parameters, the internationnal CT diagnostic reference levels, and the use and limitation of the CT effective dose. In addition, we conducted a brief survey of the use of CT scan in some university hospitals in Thailand and estimated current CT doses at these hospitals. Our review and survey suggests that CT scanning provides a great benefit in medicine but it also becomes the major source of X-ray exposure. Radiation doses from a CT scan are much higher than most conventional radiographic procedures. This raises concerns about the carcinogenic potentials. We encourage every CT unit to adhere to the International Guidelines of CT dose parameter references. Our preliminary survey from some university hospitals in Thailand revealed that CT radiation doses are within acceptable standard ranges. However, the justification for utilization of CT scans should also be required and monitored. The importance of adequate communication between attending physician and consulting radiologist is stressed.

BENCHMARKING OF A NEW AUTOMATIC CT RADIATION DOSE CALCULATOR

2020 ◽  
Vol 191 (3) ◽  
pp. 361-368
Author(s):  
Kofi Okyere Akyea-Larbi ◽  
Mercy Afadzi Tetteh ◽  
Anne Catrine T Martinsen ◽  
Francis Hasford ◽  
Stephen Inkoom ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Conversion Coefficient ◽  
Software Tool ◽  
Dose Assessment ◽  
Organ Doses ◽  
Ct Radiation ◽  
Ct Head ◽  
Effective Doses ◽  
Patient Radiation Dose ◽  
Coefficient Method

Abstract Information on patient radiation dose is essential to meet the radiation protection regulations and the demands of dose optimization. Vendors have developed different tools for patient dose assessment for radiological purposes. In this study, estimated effective doses derived from a new image-based software tool (DoseWatch, GE Healthcare) was benchmarked against the corresponding doses from a dose calculator (CT-Expo, SASCRAD) and a conversion coefficient method. Dose data from 150 adult patients (66 male and 84 female), who underwent CT head, abdominopelvic or chest examinations, were retrospectively collected using DoseWatch. Effective dose estimated by DoseWatch was significantly lower than that of CT-Expo and DLP-E (k) (p ≤ 0.001). For the organ doses, DoseWatch resulted in lower dose than CT-Expo for all the organs with the exception of testis (p ≤ 001) and eye lenses (p ≤ 0.026).

Organ-Based Computed Tomographic (CT) Radiation Dose Reduction to the Lenses

2012 ◽  
Vol 36 (3) ◽  
pp. 334-338 ◽  
Author(s):  
Anja Judith Reimann ◽  
Chris Davison ◽  
Thor Bjarnason ◽  
Thakur Yogesh ◽  
Karl Kryzmyk ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Dose Reduction ◽  
Radiation Dose Reduction ◽  
Computed Tomographic ◽  
Ct Radiation

Radiation exposure in patients (pts) with newly diagnosed breast cancer (BC) within first year (yr) from diagnostic procedures (DP).

2013 ◽  
Vol 31 (26_suppl) ◽  
pp. 123-123
Author(s):  
Lubna Chaudhary ◽  
Sarah Knapp ◽  
Samuel Hester ◽  
Sijin Wen ◽  
Jie Xiao ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Radiation Exposure ◽  
Background Radiation ◽  
Ductal Carcinoma ◽  
Lobular Carcinoma ◽  
Diagnostic Procedures ◽  
Radiation Doses ◽  
X Rays ◽  
Computed Tomographic ◽  
Increased Risk

123 Background: Radiation exposure is associated with an increased risk of secondary cancers. Few studies have examined radiation exposure from DP in BC. Methods: We retrospectively analyzed the cumulative radiation doses (millisievert [mSv]) of routine DP done in 305 pts during the 1st yr following BC diagnosis between Jan 2008-Oct 2010. Data regarding the frequency of DP including mammograms, sentinel lymph node biopsies, X-rays, computed tomographic (CT) and/or positron emission tomographic (PET) scans, MUGA scans and bone scans were collected. Mean radiation doses of DP were obtained from Departments of Nuclear Medicine and Radiation at our institution. Kruskal-Wallis test and post-hoc pairwise comparisons were used to assess the influence of various factors including age, histology, ER/PR (Estrogen/Progesterone) status and stage on the amount of radiation exposure. Results: Mean radiation exposure relative to various factors is shown in the Table. Pts < 40yrs had a significantly higher radiation dose as compared to pts > 60yrs (35.9mSv vs. 19.2mSv; p = 0.009). Pts with DCIS (ductal carcinoma in situ) had a significantly less radiation exposure as compared to IDC (infiltrating ductal carcinoma) and ILC (invasive lobular carcinoma) (8.5mSv vs. 26.7mSv and 22.4mSv respectively; p< 0.0001). Stage ≥ IIB disease was associated with a significantly higher radiation exposure (p< 0.0001). Stage ≥ IIIA was the only factor associated with a higher radiation dose from PET/CTs (p< 0.0001). Conclusions: Radiation exposure from DP is significant in the 1st yr of BC diagnosis, especially for younger and advanced stage pts. Risk is small but relevant, especially in younger pts. [Table: see text]

scholarly journals Cost Effectiveness of Transbronchial Needle Aspiration

1999 ◽  
Vol 6 (4) ◽  
pp. 332-335 ◽  
Author(s):  
Jennifer A Crocket ◽  
Eric YL Wong ◽  
Dale C Lien ◽  
Khanh Gia Nguyen ◽  
Michelle R Chaput ◽  
...  
Keyword(s):  
Cost Effectiveness ◽  
Cost Effective ◽  
Diagnostic Procedures ◽  
Needle Aspiration ◽  
Benign Disease ◽  
University Hospital ◽  
High Yield ◽  
Transbronchial Needle Aspiration ◽  
Computed Tomographic ◽  
The Cost

OBJECTIVE: To evaluate the yield and cost effectiveness of transbronchial needle aspiration (TBNA) in the assessment of mediastinal and/or hilar lymphadenopathy.DESIGN: Retrospective study.SETTING: A university hospital.POPULATION STUDIED: Ninety-six patients referred for bronchoscopy with computed tomographic evidence of significant mediastinal or hilar adenopathy.RESULTS: Ninety-nine patient records were reviewed. Three patients had two separate bronchoscopy procedures. TBNA was positive in 42 patients (44%) and negative in 54 patients. Of the 42 patients with a positive aspirate, 40 had malignant cytology and two had cells consistent with benign disease. The positive TBNA result altered management in 22 of 40 patients with malignant disease and one of two patients with benign disease, thereby avoiding further diagnostic procedures. The cost of these subsequent procedures was estimated at $27,335. No complications related to TBNA were documented.CONCLUSIONS: TBNA is a high-yield, safe and cost effective procedure for the diagnosis and staging of bronchogenic cancer.

Pediatric CT Radiation Dose: How Low Can You Go?

2009 ◽  
Vol 192 (5) ◽  
pp. 1292-1303 ◽  
Author(s):  
Mervyn D. Cohen
Keyword(s):  
Radiation Dose ◽  
Pediatric Ct ◽  
Ct Radiation

scholarly journals Radiation Awareness for Endovascular Abdominal Aortic Aneurysm Repair in the Hybrid Operating Room: An Instant Operator Risk Chart for Daily Practice

2021 ◽  
pp. 152660282110074
Author(s):  
Quirina M. B. de Ruiter ◽  
Frans L. Moll ◽  
Constantijn E. V. B. Hazenberg ◽  
Joost A. van Herwaarden
Keyword(s):  
Radiation Dose ◽  
Dose Rate ◽  
Effect Size ◽  
Radiation Risk ◽  
Dose Limit ◽  
Access Site ◽  
Femoral Access ◽  
Dose Rates ◽  
Rate Prediction ◽  
Operator Dose

Introduction: While the operator radiation dose rates are correlated to patient radiation dose rates, discrepancies may exist in the effect size of each individual radiation dose predictors. An operator dose rate prediction model was developed, compared with the patient dose rate prediction model, and converted to an instant operator risk chart. Materials and Methods: The radiation dose rates (DRoperator for the operator and DRpatient for the patient) from 12,865 abdomen X-ray acquisitions were selected from 50 unique patients undergoing standard or complex endovascular aortic repair (EVAR) in the hybrid operating room with a fixed C-arm. The radiation dose rates were analyzed using a log-linear multivariable mixed model (with the patient as the random effect) and incorporated varying (patient and C-arm) radiation dose predictors combined with the vascular access site. The operator dose rate models were used to predict the expected radiation exposure duration until an operator may be at risk to reach the 20 mSv year dose limit. The dose rate prediction models were translated into an instant operator radiation risk chart. Results: In the multivariate patient and operator fluoroscopy dose rate models, lower DRoperator than DRpatient effect size was found for radiation protocol (2.06 for patient vs 1.4 for operator changing from low to medium protocol) and C-arm angulation. Comparable effect sizes for both DRoperator and DRpatient were found for body mass index (1.25 for patient and 1.27 for the operator) and irradiated field. A higher effect size for the DRoperator than DRpatient was found for C-arm rotation (1.24 for the patient vs 1.69 for the operator) and exchanging from femoral access site to brachial access (1.05 for patient vs 2.5 for the operator). Operators may reach their yearly 20 mSv year dose limit after 941 minutes from the femoral access vs 358 minutes of digital subtraction angiography radiation from the brachial access. Conclusion: The operator dose rates were correlated to patient dose rate; however, C-arm angulation and changing from femoral to brachial vascular access site may disproportionally increase the operator radiation risk compared with the patient radiation risk. An instant risk chart may improve operator dose awareness during EVAR.

Preoperative Use of CT Angiography in Infants With Coarctation of the Aorta

2017 ◽  
Vol 8 (2) ◽  
pp. 196-202 ◽  
Author(s):  
Kirsten Rose-Felker ◽  
Joshua D. Robinson ◽  
Carl L. Backer ◽  
Cynthia K. Rigsby ◽  
Osama M. Eltayeb ◽  
...  
Keyword(s):  
Radiation Dose ◽  
Surgical Approach ◽  
New Technology ◽  
Three Dimensional ◽  
Coarctation Of The Aorta ◽  
Computed Tomographic Angiography ◽  
Great Vessel ◽  
Z Score ◽  
Computed Tomographic ◽  
Tomographic Angiography

Background: Computed tomographic angiography (CTA) and echocardiography (echo) are used preoperatively in coarctation of the aorta to define arch hypoplasia and great vessel branching. We sought to determine differences in quantitative measurements, as well as surgical utility, between modalities. Methods: Infants (less than six months) with both CTA and echo prior to coarctation repair from 2004 to 2013 were included. Measurements were compared and correlated with surgical approach. Three surgeons reviewed de-identified images to predict approach and characterize utility. Computed tomographic angiography radiation dose was calculated. Results: Thirty-three patients were included. No differences existed in arch measurements between echo and CTA ( z-score: −2.59 vs −2.43; P = .47). No differences between modalities were seen for thoracotomy ( z-score: −2.48 [echo] vs −2.31 [CTA]; P = .48) or sternotomy ( z-score: −3.13 [echo] vs −3.08 [CTA]; P = .84). Computed tomographic angiography delineated great vessel branching pattern in two patients with equivocal echo findings ( P = .60). Surgeons rated CTA as far more useful than echo in understanding arch hypoplasia and great vessel branching in cases where CTA was done to resolve anatomical questions that remain after echo evaluation. Two of three surgeons were more likely to choose the surgical approach taken based on CTA (surgeon A, P = .02; surgeon B, P = .01). Radiation dose averaged 2.5 (1.6) mSv and trended down from 2.9 mSv (1.8 mSv; n = 20) to 1.6 mSv (0.5 mSv; n = 7) ( P = .06) with new technology. Conclusion: Although CTA and echo measurements of the aorta do not differ, CTA better delineates branching and surgeons strongly prefer it for three-dimensional arch anatomy. We recommend CTA for patients with anomalous arch branching patterns, diffuse or complex hypoplasia, or unusual arch morphology not fully elucidated by echo.

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