The Actual Role of Iterative Reconstruction Algorithm Methods in Several Saudi Hospitals As A Tool For Radiation Dose Minimization of Ct Scan Examinations.

Background: Iterative reconstruction algorithm (IR) techniques were developed to maintain a lower radiation dose for patients as much as possible while achieving the required image quality and medical benefits. The main purpose of the current research was to assess the level and usage extent of IR techniques in computed tomographic (CT) scan exams. Also, the obligation of practitioners in several hospitals in Saudi Arabia to implement IR in CT exams was assessed. Material and Methodology: The recent research was based on two studies: data collection and a survey study. Data on the CT scan examinations were retrospectively collected from CT scanners. The survey was conducted using a questionnaire to evaluate radiographers' and radiologists' perceptions about IR and their practices with IR techniques. The statistical analysis results were performed to measure the usage strength level of IR methods. Results and Discussions: The IR strength level of 50% was selected for nearly 80% of different CT examinations and patients of different ages and weights. About 46% of the participants had not learned about IR methods during their college studies, and 54% had not received formal training in applying IR techniques. Only 32% of the participants had adequate experience with IR. Half of the participants were not involved in the updating process of the CT protocol. Conclusion: The results indicate that the majority of radiographer and radiologist at four different hospitals in Saudi Arabia have no explicit or understandable knowledge of selecting IR strength levels during the CT examination of patients. There is a need for more training in IR applications for both radiologists and radiographers. Training sessions were suggested to support radiographers and radiologists to efficiently utilize IR techniques to optimize image quality. Further studies are required to adjust CT exam protocols effectively to utilize the IR technique.

Evaluation of Pediatric Imaging Modalities Practices of Radiologists and Technologists: A Survey-Based Study.

Introduction: Radiation protection for pediatric patients is the main concern in pediatric computed tomography (CT) due to their sensitive organs, such as the brain and the thyroid glands. Accordingly, an optimization of pediatric CT practices is vital to minimize the radiation dose for this population. Aim: To assess the pediatric CT practices of radiologists and technologists in a CT unit. Materials and Methods: The study was conducted among 26 hospitals, located in various regions in Saudi Arabia. A total of 200 hard copies of the questionnaire were distributed manually and were collected for analysis. In total, 117 completed surveys were gathered from technologies, while 49 were gathered from radiologists. Results: In the case of infants with hydrocephalus, 65% of the radiologists ordered an ultrasound (US), 24% ordered a head CT scan, and 10% ordered a magnetic resonance imaging (MRI) and general X-ray for diagnosis. For pediatric patients complaining of persistent headache, 59% and 27% of the radiologists recommended CT and MRI, respectively, for diagnosis. Conclusion: Most of the radiologists utilize CT head scan to diagnose persistent headache (by 59%) and ventriculoperitoneal shunt (VPS) malfunction (by 41%) in pediatric patients compared with the other modalities. The use of CT can increase the risk of later malignancy among pediatric patients due to radiation exposure. Alternative imaging modalities such as US and MRI (non-ionized radiation) should be considered to reduce the ionizing radiation hazards and optimize the current practices of radiologists. Most of the technologists follow radiation protection protocols in this study as 63% of the technologists used lead apron for pediatric patient's protection. Radiation awareness training for the technologists could improve the knowledge about the benefits of using lead apron and reduce the radiation risks in pediatric patients.

Radiologists' Knowledge and Attitudes towards CT Radiation Dose and Exposure in Saudi Arabia-A Survey Study.

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.

The Feasibility of Contrast-to-Noise Ratio on Measurements to Evaluate CT Image Quality in Terms of Low-Contrast Detailed Detectability.

Background: To evaluate contrast-to-noise ratio (CNR) measurements in assessing image quality, in the context of the detectability performance of low-contrast detail (LCD), in computed tomography (CT) images, since exposure to elevated ionising-type radiation is considered to present excessive carcinogenic risk, whilst also causing distress in study subjects. Methods: An LCD phantom module (CTP515) was utilised in the study. Three dissimilar contrast items were used to analyse the ramifications of the proportions of an object on the CNR. Three multidetector CT (MDCT) scanners were used, with 16-MDCT, 64-MDCT and 80-MDCT frameworks, respectively. The CT scans were recreated using three dissimilar remaking algorithms-soft, standard and lung. The effects exerted on the CNR by various remodelling algorithms, as well as the contrast of various objects along with the size of the objects, were explored. The Hounsfield units of each chosen object (one unit representing the outer portion of the object) and the background and the standard deviation of the noise parameter were quantified, and algorithms were developed using MATLAB. Results: The CNR information was greatly influenced by changing the image recreation calculations and was very much increased in the soft-tissue recreation images using 16-MDCT and 64-MDCT. The CNR information was also increased more in the optimum recreation images than in the reproduced images from the computational procedure used in the 80-MDCT. The results did not show any remarkable contrasts in the CNR values between the different object sizes. Overall, a higher kVp produced an improved CNR in all the CT scanners. In particular, there were prominent upgrades in the CNR information when the kVp was increased from 80 to 120. Higher mAs levels gave better CNR values overall, especially for greater section thicknesses. Based on the CNR estimations, the 64-MDCT provided the best correlation among the CT scanners. Conclusions: The objective LCD appraisal method, based on CNR measurements, was confirmed as being useful for checking the different impacts of kVp, mAs and section thickness on the nature of the picture. This procedure was similarly viable in assessing the impacts of the different reconstruction calculations and the different differentiation questions on the nature of the image.

Evaluation of radiographers' knowledge and attitudes of image quality optimisation in paediatric digital radiography in Saudi Arabia and Australia: a survey-based study.

INTRODUCTION: Digital radiography (DR) systems enable radiographers to reduce the radiation dose to patients while maintaining optimised image quality. However, concerns still exist about paediatric patients who may be exposed to an increased level of radiation dose which is not needed for clinical practice. The purpose of this study was to evaluate the knowledge, awareness and attitudes, in terms of image quality optimisation of radiographers undertaking paediatric DR in Australia and Saudi Arabia. METHODS: A survey-based study was devised and distributed to radiographers from Australia and Saudi Arabia. Questions focused on Australian and Saudi Arabian radiographers' knowledge and attitude of paediatric DR examinations. RESULTS: There were 376 participants who responded to the survey from both countries. A major finding showed that most participants lack knowledge in the area of paediatric DR examinations. Most participants from Australia had received no formal training in paediatric digital radiography (79%), whereas nearly half of the participants from Saudi Arabia received no training (45%). Approximately three out of four radiographers from both countries believed that when using DR they did not need to change the way they collimate the beam as DR images can be cropped using post-processing methods. CONCLUSION: The finding of this study demonstrates that radiographers from both countries should improve their understanding and clinical use of DR in paediatric imaging. More education and training for both students and clinicians is needed to enhance radiographer performance in digital radiography and improve their clinical practices.

Radiographers' Ability to Detect Low-Contrast Detail in Digital Radiography Systems.

PURPOSE: To evaluate radiographers' ability to detect low-contrast detail using various digital planar radiographic systems. METHODS: A low-contrast detail phantom was placed between two 5-cm thick Perspex sheets (Lucite International). Images were obtained using different kilovoltage peak and milliamperage second (mAs) settings with computed radiography (CR), indirect conversion digital radiography (IDR), and direct conversion digital radiography (DR) systems. Six groups of 6 radiographers were asked to score 39 images; each group scored 2 images from each system for a total of 6 images. The seventh group scored only one image from each system for a total of 3 images. The radiographers' results were compared with the results of analyzer software. The inverse image quality factor was used to measure low-contrast detail detectability performance. RESULTS: Radiographers performed significantly worse than the computerized software in determining low-contrast detail in planar radiographic images (P < .01). However, a positive correlation (R = 0.558) existed between the 2 sets of scores in terms of low-contrast detail detectability performance. DISCUSSION: On average, radiographers were able to detect increased image quality resulting from increased mAs. Radiographers reached results similar to the software regarding whether IDR and DR have better detectability performances than CR. Differences found among individual radiographers were not as significant with DR. CONCLUSION: When radiographers' performance in detecting low-contrast detail was evaluated and compared with that of the software, radiographers exhibited poorer performances. Because radiographers are responsible for image quality optimization, additional training might improve their ability to detect low-contrast detail in DR systems.

Effects of radiographic techniques on the low-contrast detail detectability performance of digital radiography systems.

PURPOSE: To evaluate the effects of the radiation exposure factors kilovolt peak and tube current time (milliampere seconds) on the low-contrast detail detectability performance of 3 types of planar digital radiography systems. Detectability performance of an imaging system refers to its ability to detect and present the low-contrast details of organs in the acquired image. The authors also compare detectability performance between computed radiography, indirect digital radiography, and direct digital radiography by evaluating low-contrast details of the obtained images. METHODS: A low-contrast detail phantom was inserted within 10-cm thicknesses of Perspex plastic sheets. The images were obtained with various kilovolt peak and milliampere second settings for each of the 3 digital radiography systems. Artinis CDRAD Analyser software was used to score the images and calculate the inverse image quality figure (IQFinv). RESULTS: The higher milliampere second levels in each kilovolt peak selection resulted in higher IQFinv in computed radiography and indirect and direct digital radiography. IQFinv values significantly increased in indirect digital radiography with increasing kilovolt peak in only 1 and 2 mAs. There were insignificant differences in IQFinv values when altering kilovolt peak in each milliampere second level in direct digital radiography. The indirect digital radiography system generally demonstrated better detectability performance than computed radiography and direct digital radiography. However, direct digital radiography demonstrated better detectability performance than indirect digital radiography at lower kilovolt peak and milliampere second settings, as did computed radiography at lower kilovolt peak settings. DISCUSSION: Higher milliampere second settings increase photon count, which results in a higher signal-to-noise ratio and thus increased detectability. Lower milliampere second settings increase noise level on images, which increases the risk of diagnostic detail loss. Changing the kilovolt peak at the different milliampere second settings essentially did not affect the IQFinv of the different digital radiography systems. CONCLUSION: Increasing milliampere seconds in all digital imaging systems generally improves detectability performance. However, altering the kilovolt peak setting does not significantly change the IQFinv and detectability of objects in a digital radiograph. Imaging system selection should be based on typical radiographic examinations. Indirect digital radiography systems are better for studies that require higher kilovolt peak, such as large organs, and direct digital radiography is better for studies that require low kilovolt peak, such as small organs and mammography, which is used to examine fine tissue details.

Factors Affecting Contrast-Detail Performance in Computed Tomography: A Review.

This article reports on recent research findings into the factors that influence the detectability performance of different systems of computed tomography (CT) scanners. These systems include multidetector CT (MDCT) of different slice numbers, dual-source CT (DSCT), and cone-beam CT (CBCT). The introduction of more slices for MDCT, DSCT, and the new technology of CBCT increases the need to optimize the image quality and to examine the potential reduction of radiation doses to the patient. Low-contrast detail detectability is a method that has proven to be an appropriate evaluation method for this purpose. However, it is essential to recognize factors that affect detectability performance and understand how these factors influence image quality and radiation dose. It is argued that deep understanding of the influences of these factors is the key to image quality optimization in terms of contrast-detail detectability and radiation dose reduction. The purpose of this article is, therefore, to specify these factors and to explain their influence on detectability performance and hence on CT image quality. Further low-contrast detail studies are required to optimize imaging performance of different CT systems and scanners.