Number Of Computed Tomography Examinations Research Articles

Trends of Computed Tomography Scan Usage among Adults and Children in Yazd Province, Iran, before the Outbreak of COVID-19

Purpose: Excessive use of Computed Tomography (CT) has become a worrying issue due to the potential risks resulting from radiation exposure. This study was carried out to investigate trends in CT usage in Yazd Province, Iran.
 Materials and Methods: In the current study, patients were categorized according to their sex and age into two general groups, pediatrics (<18 years old) and adults (≥18 years old), each group falling into multiple subcategories. The performed CT scans were classified into six categories, based on the anatomical area of interest, including head/neck, chest, spine, abdomen-pelvis, extremities, and CT angiography (CTA). The data were collected from 2015 to 2018.
 Results: The mean number of CT scans increased by the Compound Annual Growth Rate (CAGR) of 11%. Across the procedures, head/neck (with an average contribution of 52% to all CT scans) was the most frequently examined region, whereas CTA had the lowest percentage (2%). More than half of the scans are performed on people over the age of 90, and among those aged<18 years old the most CT scan rates are related to 13-18-year-olds.
 Conclusion: The number of CT examinations is clearly increasing in Yazd Province. Some of this increase may be warranted because of the improvements in the diagnostic power of CT. The estimated number of pediatric CT scans has risen more than past. Due to the risk of cancer, efforts should be made to reduce unnecessary CT scans.

ANNUAL EXPOSURE OF THE SWISS POPULATION FROM MEDICAL IMAGING IN 2018.

Nationwide surveys on radiation dose to the population from medical imaging are recommended in order to follow trends in population exposure. The goal of the 2018 survey was to investigate the current exposure. The invoice coding information was collected in five university hospitals and large clinics. To improve the estimation of the effective dose delivered in computed tomography (CT), we collected dose data from different Dose Archiving Communication Systems. On average, we found that 1.2 radiological examinations per year and per inhabitant were performed. Dental radiography was the most frequent examination (48% of all the X-ray examinations), followed by conventional radiography (36%) and CT (11%). The average annual effective dose was estimated to be 1.48 mSv per inhabitant, with CT representing 64% of that dose. Our results show that the exposure of the Swiss population from medical imaging has remained stable since 2013, despite a 15% increase in the number of CT examinations.

Retrospective Analysis of a Modified Organizational Model to Guarantee CT Workflow during the COVID-19 Outbreak in the Tertiary Hospital of Padova, Italy.

At the beginning of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) outbreak in Italy, the cluster of Vò Euganeo was managed by the University Hospital of Padova. The Department of Diagnostic Imaging (DDI) conceived an organizational approach based on three different pathways for low-risk, high-risk, and confirmed Coronavirus Disease 19 (COVID-19) patients to accomplish three main targets: guarantee a safe pathway for non-COVID-19 patients, ensure health personnel safety, and maintain an efficient workload. Thus, an additional pathway was created with the aid of a trailer-mounted Computed Tomography (CT) scanner devoted to positive patients. We evaluated the performance of our approach from February 21 through April 12 in terms of workload (e.g., number of CT examinations) and safety (COVID-19-positive healthcare workers). There was an average of 72.2 and 17.8 COVID-19 patients per day in wards and the Intensive Care Unit (ICU), respectively. A total of 176 high-risk and positive patients were examined. High Resolution Computed Tomography (HRCT) was one of the most common exams, and 24 pulmonary embolism scans were performed. No in-hospital transmission occurred in the DDI neither among patients nor among health personnel. The weekly number of in-patient CT examinations decreased by 27.4%, and the surgical procedures decreased by 29.5%. Patient screening and dedicated diagnostic pathways allowed the maintenance of high standards of care while working in safety.

Radiation Dose Associated with Multi-Detector 64-Slice Computed Tomography Brain Examinations in Khartoum State, Sudan.

SummaryBackgroundRadiation exposure due to computed tomography (CT) has become an important issue, as the number of CT examinations has been increasing worldwide. Radiation doses associated with CT are higher in comparison to other imaging procedures. CT-related radiation doses should be monitored and controlled in order to ensure reduction of radiation exposure and optimization of image quality. The aim of this study was to evaluate radiation doses in adult patient who underwent routine CT brain examinations, and to assess how CT scanning protocols affect patient doses in practice.Material/MethodsA total of 118 patients underwent brain CT at two radiology departments equipped with 64-slice CT scanners, Khartoum, Sudan. Patient doses regarding weighted CT dose index (CTDIw) and dose length product (DLP) values were recorded. Quality control tests were performed for both scanners.ResultsThe mean CTDIw values ranged from 62.9 to 65.8 mGy, DLP values ranged from 1003.7 to 1192.5 mGy, and the effective dose varied from 2.4 to 3.7 mSv.ConclusionsPatient doses in this study was higher compared to previous research, suggesting that patients exposed to unnecessary radiation. Therefore, optimization of radiation doses with the use of specified imaging protocols, well-documented indications for CT, training of technicians, and quality control programs will reduce the necessary radiation doses. Establishment of the diagnostic reference level is recommended for further dose reduction.

Clinical indications and radiation doses to the conceptus associated with CT imaging in pregnancy: a retrospective study.

To perform an internal audit at a university hospital with the aim of evaluating the number, clinical indication and operating procedure of computed tomography (CT) performed on pregnant patients and of estimating the radiation doses to the conceptus. A retrospective review was conducted of all CT examinations performed in a single centre on pregnant patients between January 2008 and July 2013. The radiation doses to the conceptus were estimated. The results were compared with published data. The number of CT examinations during pregnancy increased from 3-4 per year in 2008-2011 to 11 per year in 2012. The mean estimated conceptus radiation dose was considered negligible for CT of the head and cervical spine, being less than 0.01 mGy, and for CT of the chest, less than 0.1 mGy. The estimated conceptus radiation dose from abdominopelvic CT was on average 28.7 mGy (range 6.7-60.5 mGy). The number of CT scans of pregnant patients increased threefold during the last few years. Most clinical indications and doses were in line with good clinical practice and literature; only in two cases the dose to the conceptus was higher than 50 mGy. • An increase in CT imaging of pregnant patients is of concern. • Clinical indications were in line with good practice. • Estimated conceptus doses were lower or similar to published data. • Internal guidelines for appropriate use of imaging during pregnancy should be established.

The Influence of Population Aging and Size on the Number of CT Examinations in The Netherlands

Exposures to ionizing radiation from medical examinations are on the rise. An important cause for this has been the advent and ever-increasing use of computed tomography (CT) scans for diagnostic purposes. It is often implied that population aging contributes significantly to this rise. Here, the trends in population statistics are compared to the trend in the number of CT scans in the Netherlands for the period 2002-2010. It is concluded that population growth and population aging cannot explain the observed rise in CT examinations. In fact, these factors contribute only 17% to this rise, indicating that there must be other factors that are far more important.

Radiation exposure from computed tomography in blunt trauma patients

Introduction. Computed tomography (CT) has many diagnostic advantages, spurring growth in the number of CT exami-nations. As the use of CT increases, the potential for radiation-induced adverse effects has become an issue. The primary objective of this study was to assess the liberal use of CT induced radiation exposure in patients with multiple blunt traumas. The secondary objective was to investigate the factors affecting the estimated effective dose resulting from CTs unrelated to final diagnosis.Methods. Using data from our hospital information system, we selected patients assigned a trauma code, according to the Korean Standard Classification of Diseases, and with three or more body lesions assessed by CT at the same time in the emergency department. Each CT conducted was categorized into ‘CT related to the final diagnosis’ or ‘CT unrelated to final diagnosis’. The characteristics and estimated effective dose of CTs unrelated to the final diagnosis were analyzed. The factors affecting the estimated effective dose of CTs unrelated to final diagnosis were investigated. Results. More than half of all CT examinations were not associated with the final diagnosis. The additional estimated effec-tive dose due to CTs being unrelated to the final diagnosis in each patient was a sufficient amount of radiation exposure to increase the possibility of fatal cancer.Conclusion. A considerable number of CT scans were unrelated to the patient’s final diagnosis, which exposes the patient to additional radiation exposure. 

Effects of a radiation dose reduction strategy for computed tomography in severely injured trauma patients in the emergency department: an observational study

BackgroundSeverely injured trauma patients are exposed to clinically significant radiation doses from computed tomography (CT) imaging in the emergency department. Moreover, this radiation exposure is associated with an increased risk of cancer. The purpose of this study was to determine some effects of a radiation dose reduction strategy for CT in severely injured trauma patients in the emergency department.MethodsWe implemented the radiation dose reduction strategy in May 2009. A prospective observational study design was used to collect data from patients who met the inclusion criteria during this one year study (intervention group) from May 2009 to April 2010. The prospective data were compared with data collected retrospectively for one year prior to the implementation of the radiation dose reduction strategy (control group). By comparison of the cumulative effective dose and the number of CT examinations in the two groups, we evaluated effects of a radiation dose reduction strategy. All the patients met the institutional adult trauma team activation criteria. The radiation doses calculated by the CT scanner were converted to effective doses by multiplication by a conversion coefficient.ResultsA total of 118 patients were included in this study. Among them, 33 were admitted before May 2009 (control group), and 85 were admitted after May 2009 (intervention group). There were no significant differences between the two groups regarding baseline characteristics, such as injury severity and mortality. Additionally, there was no difference between the two groups in the mean number of total CT examinations per patient (4.8 vs. 4.5, respectively; p = 0.227). However, the mean effective dose of the total CT examinations per patient significantly decreased from 78.71 mSv to 29.50 mSv (p < 0.001).ConclusionsThe radiation dose reduction strategy for CT in severely injured trauma patients effectively decreased the cumulative effective dose of the total CT examinations in the emergency department. But not effectively decreased the number of CT examinations.

Evaluation of Dose Reduction and Image Quality in Pediatric Multi-Detector CT

The number of CT (computed tomography) examinations in the diagnosis field has increased, and X-ray exposure to patients has also continued to increase. As the number of CT examinations is increasing in the general population, the number of pediatric CT examinations is rapidly increasing as well. The radiation dose from CT for pediatric patients remains a major concern because the risk related to ionizing radiations is higher in children than in adults. The purpose of this study was to evaluate radiation dose, image noise, and image contrast as a function of tube voltage (kVp) and tube current (mAs) in dierent phantoms, which were intended to simulate abdominal size, and to provide guidance on dose reduction on the basis of patient dimensions, as well as technical parameters. In this study, MDCT (multi-detector computed tomography) was used as an X-ray generator, and PMMA (polymethylmethacrylate) phantoms were used in all experiments. PMMA phantom diameters were 10 cm, 16 cm, and 32 cm corresponding to newborn, age 5, and adult abdominal sizes, respectively. To evaluate radiation dose, the CTDIw (weighted CT dose index) was calculated from the CTDI measured using ion chamber, and to evaluate image quality, image noise and image contrast were measured from a scanned image. Finally, the CNRD (dose-weighted contrast-to-noise ratio) was calculated from the radiation dose, image noise, and image contrast to optimize the technical factors. The radiation dose increased as a function of kVp and mAs and decreased as a function of the phantom diameter. Especially, for increasing tube voltage from 80 to 140 kVp, there were 395.08% and 448.27% increases in radiation dose for 10 cm and 32 cm PMMA phantoms, respectively. The image noise decreased as a function of kVp and mAs and increased as a function of the phantom diameter. And, the image contrast decreased as a function of kVp and phantom diameter and remained fixed as a function of mAs. The values of the CNRD were maximum at 80 kVp for all three phantoms. The results of this study show that it is possible to reduce radiation dose and maintain image quality through the use of lower technical factors (kVp and mAs) for small-sized phantom corresponding to pediatric patients and to provide guidance on radiation dose reduction on the basis of the patient’s dimensions.

Current utilization and radiation dose from computed tomography in patients with trauma*

To quantify the cumulative effective dose of radiation received during hospitalization after traumatic injury and to compare the computed tomography (CT) utilization practices for two time periods in patients with trauma. A retrospective analysis of radiologic and medical data. A level I trauma center. Consecutively admitted adult patients with trauma with moderate to severe injuries (injury severity score >8), an intensive care unit (ICU) length of stay of one or more days, who were directly admitted and not transferred to another acute care center. CT examination means and utilization were compared for April through August, 2003 and April to August, 2007. Cumulative effective doses were calculated for the 2007 period, and patients with a high radiation dose (>100 mSv) were identified. One hundred sixty-five adult patients with trauma were included. An increase in mean CT examinations per patient was observed in the 2007 period compared with the 2003 period, overall (4.41 vs. 3.44, p = 0.002) and among subsets of patients. The overall increase remained significant after adjustment for patient demographics (p = 0.05). The mean cumulative effective dose per patient was 11.13 mSv in 2007; 9% of patients received a dose >or=100 mSv. Patients with trauma are at an increased risk of adverse effects from CT studies, because they receive high doses of radiation, and the number of CT examinations that patients receive is increasing with time. We recommend that risk of radiation be prospectively monitored and estimated by hospitals through the use of CT examination count per patient.

Reducing radiation to children: the resident’s role

Reducing radiation to children: the resident’s role