Decreasing Radiation Exposure to the Abdomen in Children with Chronic Constipation

Background

Bowel management for children with chronic constipation may include repeated single-view abdomen radiographs (AXR) to monitor treatment success. Only one image of the abdomen is needed to include most of the colon, but technologists often make a second (or even third) exposure to be sure they have imaged the entire abdomen. Our quality improvement project aimed to reduce radiation exposure by decreasing the frequency of >1 exposure performed for AXR orders in children with chronic constipation from 27% to <10% by December 2022 and sustain.

Methods

We counted baseline (01/2020-11/2020) and intervention (12/2020-5/2023) examinations with >1 exposure. Initial interventions were a structured communication to technologists and an article in the monthly department newsletter and later, a technologist education module. Additional interventions included communication to radiologists, project updates and encouragement to all technologists, and individual technologist feedback. A statistical process control chart tracked data to study process changes over time.

Results

During the baseline and intervention periods, 525/1944 and 1329/8334 examinations, respectively, had >1 exposure performed for AXR orders. Interventions created 2 centerline shifts. Overall, examinations with >1 exposure decreased from 27% to 13.5%.

Conclusions

Frequency of >1 exposure performed for AXR orders in children with chronic constipation decreased from 27% to 13.5% through education and communication. This was sustained. We plan to assign training modules for all new technologists, policy reminders (annual training in odd years) for all technologists, and continue individualized learning opportunities.

Radiation dose considerations in digital radiography with an anti-scatter grid: A study using adult and pediatric phantoms

BACKGROUND

When using an anti-scatter grid, a decrease in receptor dose caused by its X-ray absorption seems to lead to the misperception that radiation dose needs to be increased even in digital radiography (DR).

OBJECTIVE

To demonstrate that there is no need to increase radiation dose in DR with a grid, based on a visual evaluation using an adult and a pediatric abdomen phantom (PAD and PPD , respectively).

MATERIALS AND METHODS

Phantom images with and without a grid were obtained with exposure parameters determined based on a preliminarily measured signal-to-noise ratio improvement factor (SIF), an index for potential dose reduction when using a grid. In visual evaluation, four radiologists compared phantom images with a grid applied at different dose reduction rates (0% [no reduction], 18%, 36%, and 59% for PAD and 0% and 11% for PPD ) against an image without a grid at the baseline dose (as the reference). They graded the overall image quality of the former relative to that of the latter (reference) on a 3-point scale (3 = better, 2 = almost equal, 1 = worse).

RESULTS

The mean scores for dose reduction rates of 0%, 18%, 36%, and 59% were 3.00, 3.00, 2.75, and 1.00, respectively, for PAD ; those for 0% and 11% were 2.13 and 1.63, respectively, for PPD . These results support the validity of our view that no dose increase is necessary when using an anti-scatter grid. Actually, there is even a potential for improvement in image quality with dose reduction rates of ≤36% for PAD .

CONCLUSION

It is worth reconsidering the necessity of increasing radiation dose in the DR imaging of the adult and pediatric abdomens with an anti-scatter grid.

Comparison of the different imaging modalities used to image pediatric oncology patients: A COG diagnostic imaging committee/SPR oncology committee white paper

Diagnostic imaging is essential in the diagnosis and management, including surveillance, of known or suspected cancer in children. The independent and combined roles of the various modalities, consisting of radiography, fluoroscopy, ultrasonography (US), computed tomography (CT), magnetic resonance imaging (MRI), and nuclear medicine (NM), are both prescribed through protocols but also function in caring for complications that may occur during or subsequent to treatment such as infection, bleeding, or organ compromise. Use of a specific imaging modality may be based on situational circumstances such as a brain CT or MR for a new onset seizure, chest CT for respiratory signs or symptoms, or US for gross hematuria. However, in many situations, there are competing choices that do not easily lend themselves to a formulaic approach as options; these situations depend on the contributions of a variety of factors based on a combination of the clinical scenario and the strengths and limitations of the imaging modalities. Therefore, an improved understanding of the potential influence of the imaging decision pathways in pediatric cancer care can come from comparison among the individual diagnostic imaging modalities. The purpose of the following material to is to provide such a comparison. To do this, pediatric imaging content experts for the individual modalities of radiography and fluoroscopy, US, CT, MRI, and NM will discuss the individual modality strengths and limitations.

Chest radiography and computed tomography imaging in cystic fibrosis: current challenges and new perspectives

Imaging plays a pivotal role in the noninvasive assessment of cystic fibrosis (CF)-related lung damage, which remains the main cause of morbidity and mortality in children with CF. The development of new imaging techniques has significantly changed clinical practice, and advances in therapies have posed diagnostic and monitoring challenges. The authors summarise these challenges and offer new perspectives in the use of imaging for children with CF for both clinicians and radiologists. This article focuses on chest radiography and CT, which are the two main radiologic techniques used in most cystic fibrosis centres. Advantages and disadvantages of radiography and CT for imaging in CF are described, with attention to new developments in these techniques, such as the use of artificial intelligence (AI) image analysis strategies to improve the sensitivity of radiography and CT and the introduction of the photon-counting detector CT scanner to increase spatial resolution at no dose expense.

Workload and use factor data for a modern digital radiography system

The well-referenced structural shielding design NCRP Report No. 147 uses workload information based on self-reported film-screen data from the AAPM Task Group 9 survey. The aim of this study was to assess the clinical workload distributions of modern digital radiography (DR) systems in general hospital and pediatric-only practices. A retrospective analysis of DR imaging data on four radiographic systems in a hospital practice and two radiographic systems in a pediatric practice, through a custom clinical DICOM header analytics program. A total of 203, 294 exposures from the general hospital practice and 25,415 from the pediatric practice from 2019 and 2021 were included. Values for kVp, mAs, and detector type (wall bucky, table bucky, or free detector) were extracted. For each exam, mAs was accumulated in a kVp histogram with bins 5 kVp wide and further parsed by detector type. Total workload was calculated by summing all exposures, then normalized by the number of patients. The median (25th and 75th percentile) workload in the hospital practice was 0.43 (0.22, 1.13) mA-min per patient, while the average was 1.36 ± 3.08. Pediatric data yielded a median (25th and 75th percentile) of 0.10 (0.05, 0.23) and an average of 0.29 ± 0.69 mA-min per patient. Mean number of patients per week was 230 adult and 57 pediatric. Hospital workload data is approximately 44% less than the NCRP Report No. 147 value.

Exposure index in digital radiography: initial results of awareness and knowledge from Nigerian digital radiography practices

INTRODUCTION

Exposure Index (EI) is incorporated into Digital Radiography (DR) systems to indicate incorrect exposure to enable matching exposure to the desired speed class of operation. However, knowledge of the utilization of EI by radiographers in a low-income country has not been investigated.

METHODS

A pre-tested questionnaire designed using Google forms, with open and close-ended questions was shared online with radiographers working with DR systems in public and private health facilities in some cities located in southern Nigeria. The 32-item questionnaire had two parts: Part A focused on socio-demographic characteristics and Part B focused on the respondents' awareness and knowledge of EI in DR systems. A 5-point Likert scale with 5 test items was used to assess the respondents' knowledge of EI. Statistical analyses were conducted using the Statistical Package for Social Sciences (SPSS) version 21.0. The probability value of p < 0.05 was considered statistically significant.

RESULTS

About 8.3% of the respondents had good knowledge of EI in DR systems in spite of the awareness level of 24.7%. The absence of the EI concept in DR curriculum for undergraduates, the lack of EI software in DR systems, and equipment training by the vendor engineers were reasons for the low level of knowledge of EI in DR systems.

CONCLUSION

There is low awareness and knowledge of EI by radiographers in this study, which suggests the need to maximize the benefits of EI concepts by ensuring its integration into clinical radiography practice and curriculum for undergraduates program, to improve knowledge, awareness, and practice in DR.

Beyond reflux: the spectrum of voiding cystourethrogram findings in the pediatric population

Voiding cystourethrography (VCUG) is a widely accepted radiographic imaging technique that has been traditionally used for identifying vesicoureteral reflux in children. Given the simultaneous evaluation of the lower urinary tract that is afforded by VCUG, many common and uncommon abnormalities of the ureters, bladder and urethra can also be elucidated. Knowledge of the appearance of these urological entities may facilitate their proper identification.

A new stationary grid, with grid lines aligned to pixel lines with submicron-order precision, to suppress grid artifacts

PURPOSE

We have developed a new stationary grid named a pixel-aligned grid (PA grid), in which the grid lines are aligned to the pixel lines with submicron-order precision. Further, we have evaluated its performance relative to that of a conventional grid combined with grid-line removal (GLR) processing.

METHODS

A flat-panel detector system of an indirect type, with a pixel pitch of 150 μm, was employed. Four PA grids having a grid ratio of 6:1 associated with abdominal bedside radiography, with the grid-line pitch (GP) varied around the target value of 150 μm, were produced. Blank images were obtained with four PA grids for measuring the period and amplitude of the grid artifact. In performance evaluation, acrylic and anthropomorphic abdominal phantom images were used with the PA grid, a conventional grid (40 lines/cm, grid ratio 6:1), and no grids. The grid artifacts were evaluated by power spectrum (PS) analysis. Also, the signal-to-noise ratio (SNR) improvement factor (K_SNR ) was measured.

RESULTS

Grid artifacts were hardly recognizable with PA grids with GP errors of 0.3 μm and 0.6 μm because of the prolonged grid artifact periods. The measured artifact amplitudes of these PA grids were less than 0.6%. Furthermore, the PA grids did not produce notable frequency peaks in PS. In contrast, the conventional grid without GLR processing produced two conspicuous peaks. With GLR processing, notable reductions in PS were observed around the two peak frequencies, which caused blurring in bone structures. For the acrylic thickness of 20 cm, the K_SNR s for the PA grid were around 1.4, suggesting some SNR improvement in abdominal bedside radiography.

CONCLUSION

The present study has demonstrated that PA grids with their grid-line pitches close to the pixel-line pitch within errors of 0.6 μm produce grid artifact-free images without any signal losses. Thus, the proposed PA grid will prove to be effective and useful in various clinical applications.

Inter-rater reliability in quality assurance (QA) of pediatric chest X-rays

PURPOSE

The goal of the study is to determine the inter-rater agreement on multiple factors that were utilized to evaluate the quality of pediatric chest X-ray exams from different levels of healthcare provision in an African setting.

METHODS

The image quality of pediatric chest X-rays from 3 South African medical centers of varying level of healthcare service were retrospectively assessed by 3 raters for 12 quality factors including: (1) absent body parts; (2) under inspiration; (3) patient rotation; (4) scapula in the way; (5) patient kyphosis/lordosis; (6) artefact/foreign body; (7) central vessel visualization; (8) peripheral vessels visualization; (9) poor collimation; and (10) trachea and bronchi visualization; (11) post-cardiac vessel visualization; and (12) absent or wrong image orientation. Analysis was performed using the Brennan--Prediger coefficient of agreement for inter-rater reliability and Cochran's Q statistic and McNemar's test for inter-rater bias.

RESULTS

1077 X-rays were reviewed. The least difference between observers in the frequency of the errors was noticed for factors (1) absent body parts and (12) absent or wrong image orientation with almost perfect agreement between raters. κ score for these two factors among all raters and between each pair of raters was more than 0.95 with no significant inter-rater bias. Conversely, there was poor agreement for the remaining factors with the least agreed on being factor (3) patient rotation with a κ score of 0.23. This was followed by factors (2) under inspiration (κ score of 0.32) and factors (4) scapula in the way (κ score of 0.35) respectively. There was significant inter-rater bias for all these three factors.

CONCLUSION

Many of the factors used to assess the quality of a chest X-ray in children demonstrate poor reliability despite mitigation against variations in training, standard quality definitions and level of healthcare service provision. New definitions, objective measures and recording tools for assessing pediatric chest radiographic quality are required.

Radiation use in diagnostic imaging in children: approaching the value of the pediatric radiology community

Medical imaging is foundational in the care of children, and much of the medical imaging province depends on ionizing radiation: radiography, fluoroscopy, CT and nuclear imaging. Many considerations for this imaging in children are distinct in the domains of appropriate radiation use, other factors that determine examination quality, the opportunities to engage and educate through networking, and the translation of research efforts. Given these needs, it is worth approaching the contributions and their impact by the pediatric radiology community, especially to the enhancement of this value in the care of children.

Sex differences in paediatric airway anatomy

NEW FINDINGS

What is the central question of this study? Are sex difference in the central airways present in healthy paediatric patients? What is the main finding and its importance? In patients ≤12 years we found no sex differences in central airway luminal area. After 14 years, the males had significantly larger central airway luminal areas than the females. The sex differences were minimized, but preserved when correcting for height. Luminal area is the main determinant of airway resistance and our finding could help explain sex differences in pulmonary system limitations to exercise in paediatric patients.

ABSTRACT

Cross-sectional airway area is the main determinant of resistance to airflow in the respiratory system. In paediatric patients (<18 years), previous evidence for sex differences in cross-sectional airway area was limited to patients with history of pulmonary disease or cadaveric studies with small numbers of subjects. These studies either only report tracheal data and do not include a range of ages or correct for height. Therefore, we sought to assess sex differences in airway luminal area utilizing paediatric patients of varying ages and no history of respiratory disease. Using three-dimensional reconstructions from high-resolution computed tomography scans, we retrospectively assessed the cross-sectional airway area in healthy paediatric females (n = 97) and males (n = 128) over a range of ages (1-17 years). The areas of the trachea, left main bronchus, left upper lobe, left lower lobe, right main bronchus, intermediate bronchus and right upper lobe were measured at three discrete points by a blinded investigator. No differences between the sexes were noted in the cross-sectional areas of the youngest (ages 1-12 years) patients (P > 0.05). However, in patients ≥14 years the cross-sectional areas were larger in the males compared to females in most airway sites. For instance, the cross-sectional size of the trachea was 25% (218 ± 44 vs. 163 ± 24 mm² , P < 0.01) larger in males vs. females among ages 13-17 years. When accounting for height, these sex differences in airway areas were attenuated, but persisted. Our results indicate that sex differences in paediatric airway cross-sectional area manifest after age ≥14 years and are independent of height.

Unified Open Hardware Platform for Digital X-Ray Devices; its Conceptual Model and First Implementation

Background: Digital radiography devices are still the gold standard for diagnosis or therapy guidance in medicine. Despite the similarities between all direct digital x-ray systems, researchers and new companies face significant challenges during the development phase of innovative x-ray devices; each component is manufactured independently, guidance towards device integration from manufacturers is limited, global standards for device integration is lacking. Method: In scope of this study a plug-integrate-play (PIP) conceptual model for x-ray imaging system is introduced and implemented as an open hardware platform, SyncBox. The researchers are free to select each individual device component from different vendors based on their intended application and target performance are utilized in criteria. Result: As its first implementation, SyncBox and its platform a full body high resolution radiographic scanner that employs a novel TDI digital detector. Conclusion: We believe that SyncBox has a potential for introducing an open source hardware platform to x-ray equipment design.

The difference of Use of CT in the general versus pediatric emergency departments for adolescent patients in the same tertiary hospital

OBJECTIVE

The use of computed tomography (CT) in pediatric patients has decreased since the association between radiation and cancer risk has been reported. However, in adolescent patients being treated as adult patients, there has been a high incidence of CT use in emergency departments (EDs). Thus, this study aimed to evaluate the CT use in adolescent patients with complaints of headache or abdominal pain in the general and pediatric EDs of the same hospital.

METHODS

A retrospective chart review of patients aged 15 to 18 years, who presented with headache or abdominal pain at the general and pediatric EDs of Seoul National University Hospital from January 2010 to December 2014, was conducted.

RESULTS

A total of 407 adolescent patients with complaints of headache and 980 with abdominal pain were included in this study. The adolescent patients in the general ED were more likely to undergo CT scans than those in the pediatric ED, with both patients having headache (42.4% vs. 20.5%, respectively, P<0.001) and abdominal pain (29.0% vs. 18.4%, respectively, P<0.001). There was no statistical difference in the rates of positive CT findings between the general and pediatric EDs. The frequency of visits to the general ED was associated with high rates of CT use in adolescent patients with complaints of headache (odds ratio, 3.95; 95% confidence interval, 2.01 to 7.77) and those with abdominal pain (odds ratio, 1.76; 95% confidence interval, 1.18 to 2.64).

CONCLUSION

The ED setting influences the use of CT on adolescent patients, and a child-friendly environment could reduce the radiation risks.

Visual grading analysis of digital neonatal chest phantom X-ray images: Impact of detector type, dose and image processing on image quality

OBJECTIVES

To evaluate the impact of digital detector, dose level and post-processing on neonatal chest phantom X-ray image quality (IQ).

METHODS

A neonatal phantom was imaged using four different detectors: a CR powder phosphor (PIP), a CR needle phosphor (NIP) and two wireless CsI DR detectors (DXD and DRX). Five different dose levels were studied for each detector and two post-processing algorithms evaluated for each vendor. Three paediatric radiologists scored the images using European quality criteria plus additional questions on vascular lines, noise and disease simulation. Visual grading characteristics and ordinal regression statistics were used to evaluate the effect of detector type, post-processing and dose on VGA score (VGAS).

RESULTS

No significant differences were found between the NIP, DXD and CRX detectors (p>0.05) whereas the PIP detector had significantly lower VGAS (p< 0.0001). Processing did not influence VGAS (p=0.819). Increasing dose resulted in significantly higher VGAS (p<0.0001). Visual grading analysis (VGA) identified a detector air kerma/image (DAK/image) of ~2.4 μGy as an ideal working point for NIP, DXD and DRX detectors.

CONCLUSIONS

VGAS tracked IQ differences between detectors and dose levels but not image post-processing changes. VGA showed a DAK/image value above which perceived IQ did not improve, potentially useful for commissioning.

KEY POINTS

• A VGA study detects IQ differences between detectors and dose levels. • The NIP detector matched the VGAS of the CsI DR detectors. • VGA data are useful in setting initial detector air kerma level. • Differences in NNPS were consistent with changes in VGAS.

Portable abdomen radiography: moving to thickness-based protocols

BACKGROUND

Default pediatric protocols on many digital radiography systems are configured based on patient age. However, age does not adequately characterize patient size, which is the principal determinant of proper imaging technique. Use of default pediatric protocols by inexperienced technologists can result in patient overexposure, inadequate image quality, or repeated examinations.

OBJECTIVE

To ensure diagnostic image quality at a well-managed patient radiation exposure by transitioning to thickness-based protocols for pediatric portable abdomen radiography.

MATERIALS AND METHODS

We aggregated patient thickness data, milliamperes (mAs), kilovoltage peak (kVp), exposure index (EI), source-to-detector distance, and grid use for all portable abdomen radiographs performed in our pediatric hospital in a database with a combination of automated and manual data collection techniques. We then analyzed the database and used it as the basis to construct thickness-based protocols with consistent image quality across varying patient thicknesses, as determined by the EI.

RESULTS

Retrospective analysis of pediatric portable exams performed at our adult-focused hospitals demonstrated substantial variability in EI relative to our pediatric hospital. Data collection at our pediatric hospital over 4 months accumulated roughly 800 portable abdomen exams, which we used to develop a thickness-based technique chart.

CONCLUSION

Through automated retrieval of data in our systems' digital radiography exposure logs and recording of patient abdomen thickness, we successfully developed thickness-based techniques for portable abdomen radiography.

Development of a tool to aid the radiologic technologist using augmented reality and computer vision

This technical innovation describes the development of a novel device to aid technologists in reducing exposure variation and repeat imaging in computed and digital radiography. The device consists of a color video and depth camera in combination with proprietary software and user interface. A monitor in the x-ray control room displays the position of the patient in real time with respect to automatic exposure control chambers and image receptor area. The thickness of the body part of interest is automatically displayed along with a motion indicator for the examined body part. The aim is to provide an automatic measurement of patient thickness to set the x-ray technique and to assist the technologist in detecting errors in positioning and motion before the patient is exposed. The device has the potential to reduce the incidence of repeat imaging by addressing problems technologists encounter daily during the acquisition of radiographs.

Diagnostic Medical Imaging in Pediatric Patients and Subsequent Cancer Risk

The use of diagnostic medical imaging is becoming increasingly more commonplace in the pediatric setting. However, many medical imaging modalities expose pediatric patients to ionizing radiation, which has been shown to increase the risk of cancer development in later life. This review article provides a comprehensive overview of the available data regarding the risk of cancer development following exposure to ionizing radiation from diagnostic medical imaging. Attention is paid to modalities such as computed tomography scans and fluoroscopic procedures that can expose children to radiation doses orders of magnitude higher than standard diagnostic x-rays. Ongoing studies that seek to more precisely determine the relationship of diagnostic medical radiation in children and subsequent cancer development are discussed, as well as modern strategies to better quantify this risk. Finally, as cardiovascular imaging and intervention contribute substantially to medical radiation exposure, we discuss strategies to enhance radiation safety in these areas.

Performance improvement and patient safety program-guided quality improvement initiatives can significantly reduce computed tomography imaging in pediatric trauma patients

BACKGROUND

Morbidity and mortality of cervical spine (C-spine) injury in pediatric trauma patients are high, necessitating quick and accurate diagnosis. Best practices emphasize minimizing radiation exposure through decreased reliance on computed tomography (CT), instead using clinical assessment, physical examination, and alternate imaging techniques. We implemented an institutional performance improvement and patient safety (PIPS) program initiative for C-spine clearance in 2010 because of high rates of CT scans among pediatric trauma patients.

METHODS

A retrospective review of pediatric trauma patients, aged 0 years to 14 years, in the pre- and post-PIPS implementation periods was conducted. Rates of C-spine CT, overall CT, other imaging modalities, radiation exposure, patient characteristics, and injury severity were compared, and compliance with PIPS protocol was reviewed.

RESULTS

Patient characteristics and injury severity were similar before and after PIPS implementation. C-spine CT rates decreased significantly between groups (30% vs. 13%, p < 0.001), whereas C-spine plain x-ray rates increased significantly (7% vs. 25%, p < 0.001). There was no difference in C-spine magnetic resonance imaging between groups (12% vs. 10%, p = 0.11). In 2007, 71% of patients received a CT scan for any reason. However, the overall CT rate decreased significantly between groups (60% vs. 45%, p < 0.001). There was an estimated 22% decrease in lifetime attributable risk (LAR) for any cancer due to ionizing imaging exposure in males and 38% decrease in females between the pre- and post-PIPS groups. There was a 54% decrease in LAR for thyroid cancer in males and females between groups; 2014 compliance with the protocol was excellent (82-90% per quarter).

CONCLUSIONS

Performance improvement and patient safety program-generated protocol can significantly decrease ionizing radiation exposure. We demonstrate that a simple protocol focused on C-spine imaging has high compliance, decreased C-spine CT scans, and decreased LAR for thyroid cancer. A secondary benefit is a reduction in total CT imaging, with an associated decrease in LAR for all cancers.

LEVEL OF EVIDENCE

Therapeutic study, level IV; diagnostic study, level III.

Does collimation affect patient dose in antero-posterior thoraco-lumbar spine?

INTRODUCTION

The purpose of this study is to determine the effect of collimation on the lifetime attributable risk (LAR) of cancer incidence in all body organs (effective risk) in patients undergoing antero-posterior (AP) examinations of the spine. This is of particular importance for patients suffering from scoliosis as in their case regular repeat examinations are required and also because such patients are usually young and more susceptible to the effects of ionising radiation than are older patients.

METHODS

High sensitivity thermo-luminescent dosimeters (TLDs) were used to measure radiation dose to all organs of an adult male dosimetry phantom, positioned for an AP projection of the thoraco-lumbar spine. Exposures were made, first applying tight collimation and then subsequently with loose collimation, using the same acquisition factors. In each case, the individual TLDs were measured to determine the local absorbed dose and those representing each organ averaged to calculate organ dose. This information was then used to calculate the effective risk of cancer incidence for each decade of life from 20 to 80, and to compare the likelihood of cancer incidence when using tight and loose collimation.

RESULTS

The calculated figures for effective risk of cancer incidence suggest that the risk when using loose collimation compared to the use of tight collimation is over three times as high and this is the case across all age decades from 20 to 80.

CONCLUSION

Tight collimation can greatly reduce radiation dose and risk of cancer incidence. However collimation in scoliotic patients can be necessarily limited.

Image quality and dose differences caused by vendor-specific image processing of neonatal radiographs

BACKGROUND

Image processing plays an important role in optimizing image quality and radiation dose in projection radiography. Unfortunately commercial algorithms are black boxes that are often left at or near vendor default settings rather than being optimized.

OBJECTIVE

We hypothesize that different commercial image-processing systems, when left at or near default settings, create significant differences in image quality. We further hypothesize that image-quality differences can be exploited to produce images of equivalent quality but lower radiation dose.

MATERIALS AND METHODS

We used a portable radiography system to acquire images on a neonatal chest phantom and recorded the entrance surface air kerma (ESAK). We applied two image-processing systems (Optima XR220amx, by GE Healthcare, Waukesha, WI; and MUSICA(2) by Agfa HealthCare, Mortsel, Belgium) to the images. Seven observers (attending pediatric radiologists and radiology residents) independently assessed image quality using two methods: rating and matching. Image-quality ratings were independently assessed by each observer on a 10-point scale. Matching consisted of each observer matching GE-processed images and Agfa-processed images with equivalent image quality. A total of 210 rating tasks and 42 matching tasks were performed and effective dose was estimated.

RESULTS

Median Agfa-processed image-quality ratings were higher than GE-processed ratings. Non-diagnostic ratings were seen over a wider range of doses for GE-processed images than for Agfa-processed images. During matching tasks, observers matched image quality between GE-processed images and Agfa-processed images acquired at a lower effective dose (11 ± 9 μSv; P < 0.0001).

CONCLUSION

Image-processing methods significantly impact perceived image quality. These image-quality differences can be exploited to alter protocols and produce images of equivalent image quality but lower doses. Those purchasing projection radiography systems or third-party image-processing software should be aware that image processing can significantly impact image quality when settings are left near default values.

Appropriateness of radiology procedures performed in children with gastrointestinal symptoms and conditions

BACKGROUND & AIMS

Exposure to ionizing radiation from diagnostic imaging procedures (DIPs) has been associated with an increased risk of cancer in children. In particular, gastrointestinal imaging has been identified as a significant factor that contributes to exposure of children to radiation during diagnostic procedures. We performed a longitudinal assessment of gastrointestinal-associated DIPs to identify practices that might be targeted to reduce exposure of pediatric patients to radiation.

METHODS

DIP insurance claims from 2001 through 2009 were obtained from an Independent Physicians Association in a large US metropolitan area. We retrieved and analyzed Current Procedural Terminology codes, associated International Classification of Diseases, 9th Revision, codes specific for gastrointestinal symptoms and conditions, and patient demographics associated with DIPs from insurance claims data.

RESULTS

Overall, 11,473 DIPs were performed on 6550 children with gastrointestinal symptoms; 1 in 30 patients received a DIP for a gastrointestinal complaint. Over the study period, the proportion of higher-radiation DIPs (computed tomography, fluoroscopy, and angiography) increased. Higher-radiation DIPs for gastrointestinal symptoms were performed more frequently in older children and in boys in the emergency department and in inpatient settings for diagnoses of abdominal pain, appendicitis, and noninfectious gastroenteritis.

CONCLUSIONS

Higher-radiation diagnostic imaging accounts for an increasing proportion of imaging procedures among children with gastrointestinal symptoms, even though these often are not recommended for evaluation of gastrointestinal disorders. Clinicians should be aware of these findings when ordering DIPs for gastrointestinal complaints, and clinical practice guidelines should be created to reduce diagnostic imaging-related radiation exposure in children.

Digital radiography exposure indices: A review

Digital radiography (DR) technologies have the advantage of a wide dynamic range compared to their film-screen predecessors, however, this poses a potential for increased patient exposure if left unchecked. Manufacturers have developed the exposure index (EI) to counter this, which provides radiographers with feedback on the exposure reaching the detector. As these EIs were manufacturer-specific, a wide variety of EIs existed. To offset this, the international standardised EI has been developed by the International Electrotechnical Commission (IEC) and the American Association of Physicists in Medicine (AAPM). The purpose of this article is to explore the current literature relating to EIs, beginning with the historical development of the EI, the development of the standardised EI and an exploration of common themes and studies as evidenced in the research literature. It is anticipated that this review will provide radiographers with a useful guide to understanding EIs, their application in clinical practice, limitations and suggestions for further research.

Imaging the small bowel

PURPOSE OF REVIEW

Radiologic investigations continue to play a pivotal role in the diagnosis of pathologic conditions of the small intestine despite enhancement of capsule endoscopy and double-balloon endoscopy. Imaging techniques continue to evolve and new techniques in MRI in particular, are being developed.

RECENT FINDINGS

Continued advances in computed tomography (CT) and MRI techniques have reinforced the importance of these imaging modalities in small bowel assessment. The more invasive enteroclysis technique yields better small bowel distension for both CT and MRI when compared with peroral enterography, but no clinically significant difference is seen in terms of diagnostic accuracy. Recent concern regarding radiation exposure means that MRI is gaining in popularity. Fluoroscopic studies such as barium follow through and small bowel enteroclysis are being replaced by the cross-sectional alternatives. Contrast-enhanced ultrasound is showing results comparable with CT and MRI, but concern remains regarding reproducibility, especially outside centres that specialize in advanced sonographic techniques.

SUMMARY

CT and MRI enterography are comparable first-line modalities for patients with suspected small bowel disease, but magnetic resonance enterography is favoured given the absence of ionizing radiation. Capsule endoscopy is a reasonable alternative investigation in exploration of chronic gastrointestinal blood loss, but is best kept as a second-line test in patients with other symptoms.