Optimization of Postprocessing parameters for abdominal Forensic CT scans

Aim

Postmortem Computed Tomography (PMCT) is gradually introduced at forensic institutes. Image reconstruction software can increase diagnostic potential in CT by increasing distinction between structures and reduction of artifacts. The aim of this study was to develop and evaluate novel image reconstruction parameters for postmortem conditions, to increase image quality and diagnostic potential of CT scans.

Method

Twenty PMCT scans of deceased hereof two in severe decay were subjected to four reconstruction techniques: a standard reconstruction algorithm, the detail reconstruction algorithm and two novel algorithms based on the standard algorithm, but with different Hounsfield settings. Image quality was evaluated by visual grading analysis (VGA) by four forensic radiologist observers.

Results

The VGA did not prove that any of the reconstruction techniques were superior to the others. For standard and detail, the two pre-defined reconstruction algorithms, VGA scores were indiscernible and were superior to the equally indiscernible Hounsfield reconstructions on parameters translated into Sharpness and Low Contrast Resolution. The two alternative Hounsfield settings were superior with respect to Noise and Artifacts/Beam Hardening.

Conclusion

The study elucidates the possiblity for multiple reconstructions specialized for PMCT conditions, to accommodate the special conditions when working with the deceased. Despite the lack of clear improvements in the tested reconstructions, this study provides an insight into some of the possibilities of improving PMCT quality using reconstruction techniques.

Radiographers use of social media - SoMe in a Nordic perspective

INTRODUCTION

Social media (SoMe) is widely used as a communication platform in everyday life. Also, healthcare professionals have embraced SoMe as a communication tool for both peers and patients. It is becoming an interactive tool for discussing professionals' issues and a place where learning and education occur. This study explores the specific patterns of SoMe use for radiographers' in the Nordic countries. The aim of this survey was to investigate radiographers use of social platforms in a professional setting.

METHODS

A 29-item survey was prepared, and pilot-tested. The survey was produced in Danish a language that all Nordic countries master. In general, most Nordic languages are very similar. The survey was distributed by online platforms such as Facebook, LinkedIn, Twitter/X, and also distributed by newsletters by the Norwegian and Danish national radiographers societies. All data was collected anonymously. An Ethical Research approval was obtained from the University of Southern Denmark.

RESULTS

A total of 242 respondents completed the survey (Denmark n = 183, Norway n = 48, Sweden n = 8, and n = 3 from other Scandinavian countries). The respondents included 186 females, 52 males and four were undisclosed. On average, the respondents spent approximately 2 h and 23 min daily on SoMe, with 27 min specifically dedicated to content relevant to radiographers. Facebook was the preferred platform with 93 % (n = 226). A total of 5.4 % (n = 13) respondents had experienced contact from patients and/or next of kin, while 92 % (n = 222) reported no such interactions and 2.9 % (n = 7) were undisclosed. A total of 52.8 % (n = 128) used SoMe in relation to courses, conferences, or online meetings. This shows that time spent on content relevant to radiographers imply that SoMe can be a relevant tool for reaching radiographers.

CONCLUSION

The survey demonstrates radiographers' use of SoMe for personal and professional interest, with Facebook as the preferred social media platform. SoMe were mostly used during courses, conferences, or online meetings with half of the respondent reported using SoMe platforms during working hours. These results underscore the untapped potential of SoMe in professional healthcare settings. Additionally, the study offers insight into current practices, facilitating comparisons to identify trends in SoMe usage within the radiographer community.

IMPLICATIONS FOR PRACTICE

The findings advocate for the strategic use of SoMe by radiographers', emphasizing professional networking and knowledge sharing. However, clear guidelines are necessary to ensure patient confidentiality and data security in these digital interactions.

Spot-scanning proton therapy for early breast cancer in free breathing versus deep inspiration breath-hold

BACKGROUND AND PURPOSE

Proton therapy for breast cancer is usually given in free breathing (FB). With the use of deep inspiration breath-hold (DIBH) technique, the location of the heart is displaced inferiorly, away from the internal mammary nodes and, thus, the dose to the heart can potentially be reduced. The aim of this study was to explore the potential benefit of proton therapy in DIBH compared to FB for highly selected patients to reduce exposure of the heart and other organs at risk. We aimed at creating proton plans with delivery times feasible with treatment in DIBH.

MATERIAL AND METHODS

Sixteen patients with left-sided breast cancer receiving loco-regional proton therapy were included. The FB and DIBH plans were created for each patient using spot-scanning proton therapy with 2-3 fields, robust and single field optimization. For the DIBH plans, minimum monitor unit per spot and spot spacing were increased to reduce treatment delivery time.

RESULTS

All plans complied with target coverage constraints. The median mean heart dose was statistically significant reduced from 1.1 to 0.6 Gy relative biological effectiveness (RBE) by applying DIBH. No statistical significant difference was seen for mean dose and V17Gy RBE to the ipsilateral lung. The median treatment delivery time for the DIBH plans was reduced by 27% compared to the FB plans without compromising the plan quality.

INTERPRETATION

The median absolute reduction in dose to the heart was limited. Proton treatment in DIBH may only be relevant for a subset of these patients with the largest reduction in heart exposure.

Interprofessional diagnostic management teams: a scoping review protocol

BACKGROUND

Diagnostic errors are a major problem in healthcare. In 2015, the report "Improving Diagnosis in Health Care" by the National Academies of Sciences, Engineering, and Medicine (NASEM) stated that it is likely that most people will experience at least one diagnostic error in their lifetime. The report suggests implementing diagnostic management teams, including patients and their relatives, diagnosticians, and healthcare professionals who support the diagnostic process, to limit diagnostic error and improve patient safety. Implementing interprofessional diagnostic management teams (IDMT), however, is not an easy task due to the complexity of the diagnostic processes and the traditional organization of healthcare with divided departments and healthcare professional who operate in different geographic locations. As this topic is still emerging, a scoping review is ideal to determine the scope of the body of literature on IDMT, indicate the volume of literature and studies available and identify any gaps in knowledge. In a long-term perspective, this scoping review will contribute to prevent diagnostic errors and improve patient safety, for adults and children with physical health issues.

METHODS

We will conduct this scoping review in accordance with the JBI methodology and report it based on the PRISMA-ScR. We will systematically search six databases (EMBASE, PubMed, CINAHL, Academic Search Premier, SCOPUS and Web of Science) for papers published between 1985 and 2023 that describe the use of interprofessional diagnostic management teams. The participants included will be adults and children seeking diagnostic care for physical health issues. The concept studied will be interprofessional diagnostic management teams, and the context will be the diagnostic process in the healthcare system. Studies examining the diagnostic process in psychiatry, odontology or complementary medicine will be excluded. Data extraction, including key study characteristics and findings, will be done by two reviewers independently. Any disagreement will be resolved by discussion and eventually by including the two remainder reviewers.

DISCUSSION

To our knowledge, this will be the first scoping review regarding IDMT and the derived effects on diagnostic safety and can therefore be a very important contribution to improve patient safety significantly during the diagnostic process.

PROTOCOL REGISTRATION

The project is registered at Open Science Framework (OSF) with ID: osf.io/kv2n6.

Accuracy of radiographic measurements of fracture-induced deformity in the distal radius

Background

Management of the distal radius fracture (DRF) is to some extent based on radiographic characterization of fracture displacement. It remains unclear, however, if the measurements used to quantify displacement are accurate.

Purpose

To quantify accuracy of two radiographic measurements: dorsal/volar tilt and fracture compression, measured indirectly as ulnar variance (UV), using radiostereometric analyses (RSA) as reference standard.

Material and Methods

Twenty-one fresh frozen non-fractured human cadaveric forearms (right = 11, left = 10) were thawed and eligible for inclusion. The forearms were mounted on a custom made platform that allowed for controlled forearm rotation, and they underwent two rounds of imaging (both rounds consisted of RSA and radiographs). In round one, the non-fractured forearms were radiographed. In round two, artificial DRF´s with compression and dorsal angulation were created and imaging procedures repeated. Change in tilt and UV between the non-fractured and later fractured forearms was defined as fracture-induced deformity. Deformity was measured radiographically and additionally calculated using RSA. Bland Altman analyses were used to estimate agreement between radiographically measured, and RSA calculated, fracture-induced deformity.

Results

Our results indicated that radiographs underestimate the amount of fracture-induced deformity. Mean measured differences (bias) in dorsal tilt deformity between radiographs and RSA were -2.5° for both observers. The corresponding values for UV were -1.4 mm and -1.5 mm.

Conclusion

Quantifying fracture-induced deformity on radiographs underestimated the actual deformity when compared to RSA calculated deformity. These findings suggest that clinicians, at least in part, base fracture management and potentially corrective surgery on inaccurate measurements.

Pill or pump? Nitroglycerin 0.5 mg tablet vs 0.8 mg spray: Effect on proximal vessel diameters at Coronary CT Angiography (CCTA)

INTRODUCTION

The administration of sublingual Nitroglycerin (NTG) prior to CT coronary angiography (CCTA) can be perfomed using pump spray or tablets. Choice of method seems to be based on local preference, rather than published guidelines. This retrospective analysis tested whether proximal coronary diameters differed dependent on the sublingual administration of 0.5 mg Nitroglycerin (NTG) tablets or 0.8 mg NTG spray.

METHODS

287 ECG-gated CCTA studies with optimal image quality and Agatston scores<400 were included in this retrospective analysis. 143 of the patients were dosed with NTG tablets at a dose of 0.5 mg prior to CCTA. 144 patients received 2 puffs of 0.4 mg NTG spray for a total dose of 8 mg. All were scanned on a second-generation Dual Source CT. Diameters of proximal segments of Left Main (LM), Right (RCA), Left Anterior (LAD) and circumflex (CX) coronary arteries were measured using semi-automatic electronic callipers by two blinded readers. Results were summarised as the mean of maximum and minimum diameters. Sex-specific analysis of diameters was carried out using repeated-measures ANOVA for each vessel. Agreement between readers was examined with Bland-Altman analysis and intra-class-correlation coefficient (ICC).

RESULTS

No significant differences in coronary diameters were found except in the RCA for women and LM for men. In both cases, diameters were smaller in the spray group (11 and 9%, respectively). Reader agreement was excellent, with ICC>0.96 for all vessels, and no significant bias, except in CX (0.03 mm).

CONCLUSIONS

We found no evidence for the systematic superiority of either administration method in proximal coronary vessels.

IMPLICATIONS FOR PRACTICE

Choosing between tablet or spray NTG prior to CCTA can be guided by practical, economical and hygienic considerations alone.

Liraglutide treatment is associated with progression of coronary artery fibrous plaque: a prospective 1-year follow-up study in asymptomatic patients with type 2 diabetes

OBJECTIVE

The objective of this study was to assess the association between clinically indicated liraglutide treatment and coronary artery plaque progression during 1-year follow-up in asymptomatic diabetes.

METHODS

Patients were divided into a group receiving liraglutide (Lira+) and a group not receiving liraglutide (Lira-). Coronary computed tomography angiography (CCTA) was performed to assess total atheroma volume (TAV) and subtypes of plaque volumes (dense calcium, fibrous, fibrous-fatty, and necrotic core plaque) and the plaque progression during one year follow-up.

RESULTS

Fifty-five patients (27%) receiving liraglutide and 149 (73%) how did not were included. Changes in TAV during 1-year of follow-up were similar in the two groups (38 ± 180 (Lira+) vs. -1 ± 160 mm³ (Lira-), P = 0.13). A greater increase in fibrous plaque volume was seen in the Lira + vs. the Lira- group (34 ± 129 vs. -2 ± 101 mm³, P = 0.04). Changes over 1-year in the other plaque subtypes were similar in the two groups. Treatment duration of liraglutide was not associated with changes in TAV.

CONCLUSION

In patients with T2D without known prior coronary artery disease, liraglutide treatment was associated with a significant increase in coronary artery fibrous plaque volume during 1-year follow-up.

How to set up a mobile X-ray unit in the community - Implementation initiatives for patient-centred care

BACKGROUND

Mobile X-ray unit have previously been widely used within hospitals in general, predominately for imaging patients admitted to intensive care units or for patients who cannot tolerate a visit to the radiology department. It is now possible to have an X-ray examination outside the hospital in nursing homes or to bring the service to frail, vulnerable or disabled patients. A visit to the hospital can be a frightening experience for vulnerable patients living with dementia or other neurological disorder. It can potentially have a long-term impact on the patient's recovery or behaviour. This technical note aimed to provide insight into the planning and running of a mobile X-ray unit in a Danish setting.

METHODS

This technical note draws on the lived experiences of radiographers operating and managing a mobile X-ray service, sharing experiences with the implementation process and the challenges and successes of a mobile X-ray unit.

RESULTS AND KEY FINDINGS

Successes include that frail patient, especially those with dementia, benefit from mobile X-ray examinations, as they can remain in familiar surroundings during an X-ray procedure. In general, patients experienced an increased quality of life and less need for sedation medication due to anxiety. Also, working within a mobile X-ray unit is meaningful work for radiographers. Challenges included increased physicality of work, the funding required for the mobile unit, planning a communication strategy to the referring general practitioners, and permission from authorities to perform mobile examinations.

CONCLUSION

We have successfully implemented a mobile radiography unit that provides a better service for vulnerable patients through learning from successes and challenges.

IMPLICATIONS FOR PRACTICE

The mobile radiography setup can benefit vulnerable patients and provide meaningful work for the radiographers. However, transportation of mobile radiography equipment outside the hospital includes many considerations and challenges.

COMBINING HI-RESOLUTION SCAN MODE WITH DEEP LEARNING RECONSTRUCTION ALGORITHMS IN CARDIAC CT

To investigate the impact of combining the high-resolution (Hi-res) scan mode with deep learning image reconstruction (DLIR) algorithm in CT. Two phantoms (Catphan600® and Lungman, small, medium, large size) were CT scanned using combinations of Hi-res/standard mode and high-definition (HD)/standard kernels. Images were reconstructed with ASiR-V and three levels of DLIR. Spatial resolution, noise and contrast-to-noise ratio (CNR) were assessed. The radiation dose was recorded. The spatial resolution increased using Hi-res & HD. Image noise in the Catphan600® (69%) and the Lungman (10-70%) significantly increased when Hi-res & HD was applied. DLIR reduced the mean noise (54%). The CNR was reduced (64%) for Hi-res & HD. The radiation dose increased for both small (+70%) and medium (+43%) Lungman phantoms but decreased slightly for the large ones (-3%) when Hi-res was applied. In conclusion, the Hi-res scan mode improved the spatial resolution. The HD kernel significantly increased the image noise. DLIR improved the image noise and CNR and did not affect the spatial resolution.

Can advanced edge enhancement software improve image quality to visualise tubes, catheters and wires in digital chest radiographs?

INTRODUCTION

This study aimed to test whether Advanced Edge Enhancement (AEE) software could improve the localisation of tubes, catheters or wires, while also affecting the overall image quality in chest x-rays (CXR).

METHODS

In total, 50 retrospective CXRs were included. All images were obtained utilising the Canon X-ray system (CANON/Arcoma Precision T3 DR System, Canon Europe, Amsterdam, NL) with a CXDI-810C wireless detector. A clinical image, plus three additional AEE algorithms were applied using post processing (two intensity variations 1 and 4) on all CXRs totalling 350 different images. Three radiologists evaluated the images using a subjective Absolute Visual Grading Analysis (VGA). The clinical images used in post processing were not applied as reference in the analysis. Each radiologist graded the images separately in a randomized order, with a score of three indicating suitability for diagnostic assessment.

RESULTS

The three AEE algorithms contributed to an overall improvement (average 16-49%) in visualisation of tube, catheter or wire on CXR images. The Mann-Whitney U tests showed a statistically significant (p < 0.05) improvement in contrast resolution and sharpness, indicating an increased ability to differentiate tubes, wires or catheters tips from surrounding tissues. For the noise criterion, not applying any AEE algorithm showed a significantly higher homogeneity in soft tissue (p < 0.001), reducing the ability to visualise soft tissue. The high-intensity catheter algorithm was the only algorithm to achieve a statistically significant (p = 0.017) increase in the ability to differentiate pulmonary tissues of similar density.

CONCLUSION

An overall improvement in the visualisation of tube, catheter and wire placement was obtained using the three AEE-algorithms. The bone and catheter algorithms showed the highest consistency, with the small structure algorithm underperforming in resolution and low contrast resolution. In general, image noise increased regardless of algorithm type or applied intensity. The AEE-algorithms should therefore be seen as a supplementary tool to the clinical image protocol, while having the potential to improve image quality to specific clinical situations.

IMPLICATIONS FOR PRACTICE

AEE filtered images appear to be a supplement to the current practice of using CXRs in the diagnosis in placement of catheters, tubes and wires in the chest region. The use of AEE-algorithms has the potential to improve the daily work in clinical practice, which serves the basis for further investigation of its effect on radiographic practices.

Research ethics systems, processes, and awareness across Europe: Radiography research ethics standards for Europe (RRESFE)

INTRODUCTION

The Radiography Research Ethics Standards for Europe (RRESFE) project aims to provide a cross-sectional snapshot of current research ethics systems, processes, and awareness of such, across Europe together with identifying the associated challenges, education, and training needs.

METHODS

A cross-sectional online survey targeting radiography researchers in Europe was conducted. Data collection took place between April 26 and July 12, 2021, using a snowball sampling approach. Descriptive and analytical statistics were used to identify trends in research ethics frameworks across Europe.

RESULTS

285 responses were received across 33 European and 23 non-European countries. Most (n = 221; 95%) European respondents stated ethics approval is required before commencing research in their country. Requirements around research ethics approval and awareness of such requirements varied by European region (X² (2, n = 129) = 7.234, p = 0.013) and were found to differ depending on the type of research participant and study design. Additionally, European respondents reported ethics approval is a national requirement more often than their non-European counterparts (X² (1, n = 282) = 4.316, p = 0.049). Requirements for ethics approval were also associated with the undergraduate programme duration (2-year vs. 3-year vs. 3.5 year vs. 4-year vs. multiple programme durations; X² (4, n = 231) = 10.075, p = 0.016) and availability of postgraduate training (postgraduate training available vs. postgraduate training not available; X² (1, n = 231) = 15.448, p = <0.001) within respondents' country.

CONCLUSION

Respondents from countries with longer programme durations/availability of multiple programme lengths, availability of postgraduate training, and establishment of European Qualifications Framework Level 6 were generally associated with less uncertainty and more comprehensive research ethics requirements.

IMPLICATIONS FOR PRACTICE

Results are informative of the current status of research ethics within evidence-based radiography.

Research ethics training, challenges, and suggested improvements across Europe: Radiography research ethics standards for Europe (RRESFE)

INTRODUCTION

The Radiography Research Ethics Standards for Europe (RRESFE) project aimed to provide a cross-sectional view of the current state of radiography research ethics across Europe. This included investigating education and training in research ethics, and identifying the key challenges and potential improvements associated with using existing research ethics frameworks.

METHODS

This cross-sectional online survey targeting radiography researchers in Europe was conducted between April 26 and July 12, 2021. Descriptive and analytical statistics were used to identify research ethics education and training trends. Content analysis of qualitative responses was employed to identify significant challenges and proposed improvements in research ethics frameworks of practice.

RESULTS

There were 232 responses received across 33 European countries. Most (n = 132; 57%) respondents had received some research ethics training; however, fewer participants had received training on safeguarding vulnerable patients (n = 72; 38%), diversity and inclusivity (n = 62; 33%), or research with healthy volunteers (n = 60; 32%). Training was associated with a greater perceived importance of the need for research ethics review (p = 0.031) and with the establishment of EQF Level 6 training (p = 0.038). The proportion of formally trained researchers also varied by region (p = <0.001). Time-to-ethics-approval was noted as the biggest challenge for professionals making research ethics applications.

CONCLUSION

Early and universal integration of research-oriented teaching within the radiography education framework which emphasises research ethics is recommended. Additionally, study findings suggest research ethics committee application and approval processes could be further simplified and streamlined.

IMPLICATIONS FOR PRACTICE

The survey contributes to a growing body of knowledge surrounding the importance of education and training in research ethics for assuring a high standard of research outputs in Radiography and has identified hurdles to obtaining research ethics approval for further investigation and address.

MRI interobserver reliability in rectal tumor angulation

Background

When rectal tumors are examined using magnetic resonance imaging (MRI) the perpendicular angulation of the axial T2-weighted image to the tumor axis is essential for a correct measure of the shortest distance between tumor and mesorectal facia.

Purpose

The purpose of this study was to determine the interobserver variability in rectal tumor angulation between a radiologist and a radiographer.

Material and Methods

Two observers performed the angulation independently. All MRI examinations were performed using an MRI 1.5 Tesla unit. A Bland–Altman plot was used to assess the interobserver variance and Intraclass correlation coefficient (ICC) statistic was used to assess the interobserver reliability.

Results

MRI was performed in 55 patients with rectal cancer during a one-year period (25 (45.5%) women and 30 (54.5%) men). The median age was 71 years (range 46–87 years). The rectal tumor mean length was 3.9 cm. The interobserver reliability was good (ICC = 0.83, 95% confidence interval 0.72–0.90).

Conclusion

Radiographers receiving training will be able to perform MRI rectal tumor angulation.

Collimation and Exposure Parameter Influence Image Quality and Potential Radiation Dose to the Eye Lens of Personnel in Computed Radiography of the Canine Pelvis

Introduction: The purpose of this study was to evaluate the effect of collimation on image quality and radiation dose to the eye lenses of the personnel involved in computed radiography of the canine pelvis.

Materials and Methods: A retrospective study of canine pelvic radiographs (N = 54) was undertaken to evaluate the relationship between image quality and the degree of field the collimation used. This was followed by a prospective cadaver study (N = 18) that assessed the effects on image quality and on scattered radiation dose of different collimation field areas and exposure parameters. All radiographs were analyzed for image quality using a Visual Grading Analysis (VGA) with three observers. Finally, the potential scattered radiation dose to the eye lens of personnel restraining a dog for pelvic radiographs was measured.

Results: The retrospective study showed a slightly better (statistically non-significant) VGA score for the radiographs with optimal collimation. Spatial and contrast resolution and image sharpness showed the greatest improvement in response to minimizing the collimation field. The prospective study showed slightly better VGA scores (improved image quality) with the optimal collimation. Increasing the exposure factors especially the tube current and exposure time (mAs) resulted in improved low contrast resolution and less noise in the radiographs. The potential eye lens radiation dose increased by 14, 28, and 40% [default exposures, increased the tube peak potential (kVp), increased mAs, respectively] as a result of reduced collimation (increased beam size).

Conclusion: The degree of collimation has no statistically significant on image quality in canine pelvic radiology for the range of collimation used but does have an impact on potential radiation dose to personnel in the x-ray room. With regard to radiation safety, increases in kVp are associated with less potential scatter radiation exposure compared to comparable increases in mAs.

Design of a 3D printed coronary artery model for CT optimization

INTRODUCTION

To design a custom phantom of the coronary arteries to optimize CT coronary angiography (CCTA) protocols.

METHODS

Characteristics of the left and right coronary arteries (mean Hounsfield Unit (HU) values and diameters) were collected from consecutive CCTA examinations (n = 43). Four different materials (two mixtures of glycerine, gelatine and water, pig hearts, Ecoflex™ silicone) were scanned inside a Lungman phantom using the CCTA protocol to find the closest model to in vivo data. A 3D printed model of the coronary artery tree was created using CCTA data by exporting a CT volume rendering into Autodesk Meshmixer™ software. The model was placed in an acid bath for 5 h, then covered in Ecoflex™, which was removed after drying. Both the Ecoflex™ and pig heart were later filled with a mixture of contrast (Visipaque 320 mg I/ml), NaCl and gelatin and scanned with different levels of tube current and iterative reconstruction (ASiR-V). Objective (HU, noise and size (vessel diameter) and subjective analysis were performed on all scans.

RESULTS

The gelatine mixtures had HU values of 130 and 129, Ecoflex™ 65 and the pig heart 56. At the different mA/ASiR-V levels the contrast filled Ecoflex™ had a mean HU 318 ± 4, noise 47±7HU and diameter of 4.4 mm. The pig heart had a mean HU of 209 ± 5, noise 38±4HU and a diameter of 4.4 mm. With increasing iterative reconstruction level the visualisation of the pig heart arteries decreased so no measurements could be performed.

CONCLUSION

The use of a 3D printed model of the arteries and casting with the Ecoflex™ silicone is the most suitable solution for a custom-designed phantom.

IMPLICATIONS FOR PRACTICE

Custom designed phantoms using 3D printing technology enable cost effective optimisation of CT protocols.

High-risk coronary artery plaque in asymptomatic patients with type 2 diabetes: clinical risk factors and coronary artery calcium score

BACKGROUND

High-risk coronary artery plaque (HRP) is associated with increased risk of acute coronary syndrome. We aimed to investigate the prevalence of HRP in asymptomatic patients with type 2 diabetes (T2D), and its relation to patient characteristics including cardiovascular risk factors, diabetes profile, and coronary artery calcium score (CACS).

METHODS

Asymptomatic patients with T2D and no previous coronary artery disease (CAD) were studied using coronary computed tomography angiography (CCTA) in this descriptive study. Plaques with two or more high-risk features (HRP) defined by low attenuation, positive remodeling, spotty calcification, and napkin-ring sign were considered HRP. In addition, total atheroma volume (TAV), proportions of dense calcium, fibrous, fibrous-fatty and necrotic core volumes were assessed. The CACS was obtained from non-enhanced images by the Agatston method. Cardiovascular and diabetic profiles were assessed in all patients.

RESULTS

In 230 patients CCTA was diagnostic and 161 HRP were detected in 86 patients (37%). Male gender (OR 4.19, 95% CI 1.99-8.87; p < 0.01), tobacco exposure in pack years (OR 1.02, 95% CI 1.00-1.03; p = 0.03), and glycated hemoglobin (HbA1c) (OR 1.04, 95% CI 1.02-1.07; p < 0.01) were independent predictors of HRP. No relationship was found to other risk factors. HRP was not associated with increased CACS, and 13 (23%) patients with zero CACS had at least one HRP.

CONCLUSION

A high prevalence of HRP was detected in this population of asymptomatic T2D. The presence of HRP was associated with a particular patient profile, but was not ruled out by the absence of coronary artery calcium. CCTA provides important information on plaque morphology, which may be used to risk stratify this high-risk population. Trial registration This trial was retrospectively registered at clinical trials.gov January 11, 2017 trial identifier NCT03016910.

COMPARISON OF CONVENTIONAL HAND EXAMINATION ON SIX OPTIMISED DR SYSTEMS

The purpose of this study was to investigate the challenges in comparing digital radiography (DR) systems from different vendors for various combinations of exposure factors in posterior-anterior hand radiographs. Image quality was evaluated for a range of tube voltages and tube current-time products using a technical contrast-detail (CDRAD) phantom and an anthropomorphic hand phantom. 900 technical CDRAD images were analysed providing quality figures of merit (IQFinv) and two experienced reporting radiographers using visual grading analysis (VGA) scored 108 anthropomorphic images. This study demonstrates the differences between the DR systems included. When compensating for variations in dose, Canon showed superior results for technical image quality and Fuji for visual image quality for a standard dose point at DR hand examination (ln(DAP) 1.1, 50 kV and 2.5 mAs).

The effect of forearm rotation on radiographic measurements of the wrist: an experimental study using radiostereometric analyses on cadavers

Background

Although dorsal/palmar tilt, radial inclination (RI), and ulnar variance (UV) are measurements commonly performed in wrist radiographs, the impact of forearm rotation on those measurements during the radiographic procedure is uncertain. Our aim was to determine the impact of supination and pronation on the reliability of measurements of tilt, RI, and UV.

Methods

Tantalum markers were inserted into the distal radius of 21 unfractured cadaver forearms. The forearms were radiographed in different degrees of supination and pronation. The exact degree of rotation was calculated with radiostereometric analyses. Tilt, RI, and UV were measured by two independent readers in a random and anonymised fashion. Association between forearm rotation and radiographic measurements was examined using linear regression.

Results

Forearm rotation significantly impacted the radiographically measured tilt. One degree of supination and pronation respectively increased and decreased palmar tilt with 0.68° and 0.44°, observers 1 and 2, respectively. As opposed to observer 1, observer 2 found that RI was significantly impacted by rotation with a slope of 0.08. Ulnar variance was not significantly impacted by rotation with linear regression slopes of 0.01° (95% confidence interval [CI] − 0.02–0.05, p = 0.490) and 0.02° (95% CI − 0.02–0.07; p = 0.288), observer 1 and observer 2, respectively.

Conclusion

In unfractured forearms, the radiographically measured tilt was significantly affected by rotation. Palmar tilt increased with supination and decreased with pronation. Rotation significantly affected radial inclination, although of a magnitude that is probably not clinically relevant. No significant impact on UV was found.

Anode heel effect: Does it impact image quality in digital radiography? A systematic literature review

INTRODUCTION

The anode heel effect can be used to optimize image quality and/or patient dose in digital radiography (DR). In film-screen radiography, the effect can equalize optical density in regions of varying attenuation. Clinical experience suggests that the implementation of DR has led to less awareness of anode orientation. Post-processing is assumed to compensate, but may also alter image impression and potentially obscure image details. Published evidence was examined for the influence of the anode heel effect on image quality in DR.

METHOD

A systematic literature search was carried out using PubMed, Embase, and Web of Science databases. Title and abstracts were screened blinded by three authors, according to in-/exclusion criteria, followed by full-text analysis for final inclusion. Studies where technical and/or visual image quality were reported, was included. All studies were analyzed and assigned quality scores, according to relevant questions. The authors devised a scoring system based on reported information pertaining to reproducibility, interpretation, and generalizability of the methods and conclusions.

RESULTS

Five studies were included of heterogeneous design, each with methodological shortcomings. Only a few anatomical areas were covered. Very few patients were examined, and in no studies were images evaluated by radiologists or reporting radiographers. Relevant information such as post-processing, image quality criteria and analysis was insufficient in most studies, making reproduction difficult. Results were contradictory, especially concerning technical vs visual image quality.

CONCLUSION

Limited published evidence was found quantifying the influence of the anode heel effect on image quality using DR technology. More methodologically, robust studies are needed. The published evidence neither proves nor disproves the impact of the heel effect on image quality in DR.

IMPLICATIONS FOR PRACTICE

Based on a systematic review, no firm recommendations for anode orientation relating to image quality in DR can be provided.

The influence of a novel edge enhancement software on image quality of DR hand images of patients with rheumatoid arthritis

INTRODUCTION

This study aimed to evaluate the effects of a newly developed Advanced Edge Enhancement software (AEE) (Canon Europe, Amsterdam, NL) on image quality (IQ) of Digital Radiography (DR) hand images focusing on rheumatoid arthritis (RA).

METHODS AND MATERIALS

Fifty posterior-anterior hand images with or suspected for RA were collected. For each of the 50 images, six copies were made with each their AEE algorithm settings. A total of 330 images (30 images iterated) were evaluated using relative Visual Grading Analysis (VGA) by three observers and combined into a VGA Score (VGAS). Second, 50 images of a technical Contrast Detail Radiography Phantom (CDRAD) was produced with three different AEE software settings, each at level 1,5 and without the AEE software yielding 350 CDRAD images. All images was analysed by the CDRAD Analyser and included for an objective analysis of the AEE software.

RESULTS

The VGA study showed a significant difference in image quality between a standard image and images with AEE software applied. The average VGA score of the AEE software was better than the standard images (interval between 0.2 and 0.9). The AEE algorithms at level 5 scored significantly lower for noise but significantly higher for spatial resolution, sharpness and contrast in the VGA. The CDRAD images showed that all AEE algorithms had a statistically significant improvement for level 1 and deterioration for level 5 compared to the standard image.

CONCLUSION

Overall the AEE algorithm: small structure level 1 showed an improvement of all IQ criteria in the VGA and a better technical IQ.

IMPLICATIONS FOR PRACTICE

The AEE software ought to be considered as a useful addition to the current software, possibly enabling visualisation of structures currently visible.

The impact of COVID-19 upon student radiographers and clinical training

Introduction

To investigate student clinical placement concerns and opinions, during the initial COVID-19 pandemic outbreak and to inform educational institution support planning.

Methods

Between mid-June to mid-July 2020, educational institutions from 12 countries were invited to participate in an online survey designed to gain student radiographer opinion from a wide geographical spread and countries with varying levels of COVID-19 cases.

Results

1277 respondents participated, of these 592 had completed clinical placements during January to June 2020. Accommodation and cohabiting risks were identified as challenging, as was isolation from family, travel to clinical placements, and to a lesser extent childcare. Students stated they had been affected by the feeling of isolation and concerns about the virus whilst on placement. Overall 35.4% of all respondents were ‘Not at all worried’ about being a radiographer, however, 64.6% expressed varying levels of concern and individual domestic or health situations significantly impacted responses (p ≤ 0.05). Year 4 students and recent graduates were significantly more likely to be ‘Not worried at all’ compared to Year 2 and 3 students (p ≤ 0.05). The need for improved communication regarding clinical placements scheduling was identified as almost 50% of students on clinical placements between January to June 2020 identified the completion of assessments as challenging. Furthermore, only 66% of respondents with COVID-19 imaging experience stated being confident with personal protective equipment (PPE) use.

Conclusion

Student radiographers identified key challenges which require consideration to ensure appropriate measures are in place to support their ongoing needs. Importantly PPE training is required before placement regardless of prior COVID-19 imaging experience.

Implications for practice

As the next academic year commences, the study findings identify important matters to be considered by education institutions with responsibility for Radiography training and as students commence clinical placements during the on-going global COVID-19 pandemic.

Exploring the patient perspectives of mobile X-ray in nursing homes - A qualitative explorative pilot study

INTRODUCTION

For patients with dementia, behaviour and reactions to stimuli can change and an X-ray examination in the hospital can have be a frightening experience. The aim of this study was to identify the experiences and perspectives of patients with dementia and their caregivers on receiving a mobile x-ray examination in nursing homes.

METHODS

This study was designed as a qualitative study using patient observation and semi structured interviews, with a phenomenology-hermeneutic approach. In total, 23 patients were observed during X-ray examinations in nursing homes, and six semi structured interviews were conducted with the caregivers who participated in the examination.

RESULTS

The observations and interviews indicated that a known environment, a recognizable framework and calmness were central for a patient with dementia. The patients appeared calm and relaxed during the examination in their usual environment (nursing homes) where there are less stimuli and impressions based of the observations.

CONCLUSION

Mobile X-ray examinations for patients with dementia living in nursing homes had a positive impact on patients' reactions towards the X-ray examination. The examinations were performed in the patients' usual and safe environments, where impressions and stimuli were less disturbing for patients with dementia.

IMPLICATIONS FOR PRACTICE

The mobile x-ray unit can be of benefit for patients suffering from dementia and result in less impact. The patients living in nursing homes have the opportunity to be examined in their familiar environment, because of the mobile x-ray unit.

Organ-based tube current modulation in chest CT. A comparison of three vendors

INTRODUCTION

Organ-based tube current modulation (OBTCM) is designed for anterior dose reduction in Computed Tomography (CT). The purpose was to assess dose reduction capability in chest CT using three organ dose modulation systems at different kVp settings. Furthermore, noise, diagnostic image quality and tumour detection was assessed.

METHODS

A Lungman phantom was scanned with and without OBTCM at 80-135/140 kVp using three CT scanners; Canon Aquillion Prime, GE Revolution CT and Siemens Somatom Flash. Thermo-luminescent dosimeters were attached to the phantom surface and all scans were repeated five times. Image noise was measured in three ROIs at the level of the carina. Three observers visually scored the images using a fivestep scale. A Wilcoxon Signed-Rank test was used for statistical analysis of differences.

RESULTS

Using the GE revolution CT scanner, dose reductions between 1.10 mSv (12%) and 1.56 mSv (24%) (p < 0.01) were found in the anterior segment and no differences posteriorly and laterally. Total dose reductions between 0.64 (8%) and 0.91 mSv (13%) were found across kVp levels (p < 0.00001). Maximum noise increase with OBTCM was 0.8 HU. With the Canon system, anterior dose reductions of 6-10% and total dose reduction of 0.74-0.76 mSv across kVp levels (p < 0.001) were found with a maximum noise increase of 1.1 HU. For the Siemens system, dose increased by 22-51% anteriorly; except at 100 kVp where no dose difference was found. Noise decreased by 1 to 1.5 HU.

CONCLUSION

Organ based tube current modulation is capable of anterior and total dose reduction with minimal loss of image quality in vendors that do not increase posterior dose.

IMPLICATIONS FOR PRACTICE

This research highlights the importance of being familiar with dose reduction technologies.

CAN SCATTER CORRECTION SOFTWARE REPLACE A GRID IN DR PELVIC EXAMINATIONS?

The purpose was to examine if scatter correction software could replace a grid while maintaining image quality and reducing radiation dose for pelvic DR examinations. Grid images was produced with 70 kV and 16mAs. Anthropomorphic- and Contrast Detail RADiography (CDRAD) non-grid images were produced with 60 kV, 80 kV and 90 kV combined with five different mAs and scatter correction software. The anthropomorphic images were analyzed by absolute Visual Grading Analysis (VGA). The CDRAD images were analyzed using the CDRAD analysis software. The results showed a total of 54.6% non-grid images were evaluated as unsuitable for diagnostic use by the VGA. The CDRAD grid images showed that the IQF_inv values were significantly different (p = 0.0001) when compared to every group of non-grid images. Hereby, the conclusion stated that the scatter correction software did not compensate for the loss in image quality due to scattered radiation at the exposure levels included in a pelvic examination.

Assessment of Image Quality in Digital Radiographs Submitted for Hip Dysplasia Screening

Digital radiography is widely seen to be forgiving of poor exposure technique and to provide consistent high quality diagnostic images. Optimal quality images are however not universal; sub-optimal images are encountered. Evaluators on hip dysplasia schemes encounter images from multiple practices produced on equipment from multiple manufacturers. For images submitted to the Danish Kennel Club for hip dysplasia screening, a range of quality is seen and the evaluators are of the impression that variations in image quality area associated with particular equipment. This study was undertaken to test the hypothesis that there is an association between image quality in digital radiography and the manufacturer of the detector equipment, and to demonstrate the applicability of visual grading analysis (VGA) for image quality evaluation in veterinary practice. Data from 16,360 digital images submitted to the Danish Kennel Club were used to generate the hypothesis that there is an association between detector manufacturer and image quality and to create groups for VGA. Image quality in a subset of 90 images randomly chosen from 6 manufacturers to represent high and low quality images, was characterized using VGA and the results used to test for an association between image quality and system manufacturer. The range of possible scores in the VGA was −2 to +2 (higher scores are better). The range of the VGA scores for the images in the low image quality group (n = 45) was −1.73 to +0.67, (median −1.2). Images in the high image quality group (n = 44) ranged from −1.52 to +0.53, (median −0.53). This difference was statistically significant (p < 0.001). The study shows an association between VGA scores of image quality and detector manufacturer. Possible causes may be that imaging hardware and/or software are not equal in terms of quality, that the level of support sought and given differs between systems, or a combination of the two. Clinicians purchasing equipment should be mindful that image quality can differ across systems. VGA is practical for veterinarians to compare image quality between systems or within a system over time.

Comparison of image quality in chest, hip and pelvis examinations between mobile equipment in nursing homes and static indirect radiography equipment in the hospital

INTRODUCTION

A hospital environment can be a significant burden and a health risk especially for dementia patients. Mobile x-ray equipment (ME) is used to enable imaging of these patients at home. The aim was to compare image quality (IQ) of chest, hip and pelvis images from ME to the stationary equipment (SE) used in a hospital department.

METHODS

We analysed examinations of the chest (n = 20), hip (n = 64) and pelvis (n = 32). Images were equally obtained from each setting of ME and SE. All images were graded using Visual Grading Analysis (VGA) by three radiographers (hip and pelvis) and three radiologists (chest). Technical IQ assessment was done by 80 additional images of a Contrast-Detail Radiography phantom (CDRAD).

RESULTS

All chest images were approved for diagnostic use, as well as the hip AP and pelvis images from SE. 'Approved proportion of ME images was for HIP antero-posterior (AP) and pelvis, 78% [95% CI: 52-94%] and 81% [95% CI: 54-96%] respectively. Hip axial had an overall low, but not significant different approval rate. Ordered logistic regression indicated higher IQ of HIP AP and pelvic images from SE. This contrasts that the CDRAD substudy indicated better IQ, expressed as IQF_inv, from ME.

CONCLUSION

The VGA showed higher IQ for the SE system, while the CDRAD showed higher IQ for the ME system.

IMPLICATIONS FOR PRACTICE

Dementia patients can be examined at their home if the acquisition is optimised according to image quality in conjunct to radiation dose. Performing imaging out of the hospital and coordinating the patients' further treatment are new work areas for radiographers and requires excellent communication skills.

Radiographers' perspectives' on Visual Grading Analysis as a scientific method to evaluate image quality

INTRODUCTION

Radiographers routinely undertake many initiatives to balance image quality with radiation dose (optimisation). For optimisation studies to be successful image quality needs to be carefully evaluated. Purpose was to 1) discuss the strengths and limitations of a Visual Grading Analysis (VGA) method for image quality evaluation and 2) to outline the method from a radiographer's perspective.

METHODS

A possible method for investigating and discussing the relationship between radiographic image quality parameters and the interpretation and perception of X-ray images is the VGA method. VGA has a number of advantages such as being low cost and a detailed image quality assessment, although it is limited to ensure the images convey the relevant clinical information and relate the task based radiography.

RESULTS

Comparing the experience of using VGA and Receiver Operating Characteristic (ROC) it is obviously that less papers are published on VGA (Pubmed n=1.384) compared to ROC (Pubmed n=122.686). Hereby the scientific experience of the VGA method is limited compared to the use of ROC. VGA is, however, a much newer method and it is slowly gaining more and more attention.

CONCLUSION

The success of VGA requires a number of steps to be completed, such as defining the VGA criteria, choosing the VGA method (absolute or relative), including observers, finding the best image display platforms, training observers and selecting the best statistical method for the study purpose should be thoroughly considered.

IMPLICATION FOR PRACTICE

Detailed evaluation of image quality for optimisation studies related to technical definition of image quality.

Image quality in coronary computed tomography angiography: influence of adaptive statistical iterative reconstruction at various radiation dose levels

Background Computed tomography (CT) technology is rapidly evolving and software solution developed to optimize image quality and/or lower radiation dose. Purpose To investigate the influence of adaptive statistical iterative reconstruction (ASIR) at different radiation doses in coronary CT angiography (CCTA) in detailed image quality. Material and Methods A total of 160 CCTA were reconstructed as follows: 55 scans with filtered back projection (FBP) (650 mA), 51 scans (455 mA) with 30% ASIR (ASIR30), and 54 scans (295 mA) with 60% ASIR (ASIR60). For each reconstruction, subjective image quality was assessed by five independent certified cardiologists using a visual grading analysis (VGA) with five predefined image quality criteria consisting of a 5-point scale. Objective measures were contrast, noise, and contrast-to-noise ratio (CNR). Results The CTDI_vol resulted in 10.3 mGy, 7.4 mGy, and 4.6 mGy for FBP, ASIR30, and ASIR60, respectively. Homogeneity of the left ventricular lumen was the sole aspect in which reconstruction algorithms differed with a decreasing effect for ASIR60 compared to FBP (estimated odds ratio [OR] = 0.49 [95% confidence interval (CI) = 0.32-0.76; P = 0.001]). Decreased sharpness and spatial- and low-contrast resolutions were observed when using ASIR instead of FBP, but differences were not statistically significant. Concerning objective measurements, noise increased significantly for ASIR30 (OR = 1.08; 95% CI = 1.02-1.14; P = 0.006) and ASIR60 (OR = 1.06; 95% CI = 1.01-1.12; P = 0.034) compared to FBP. Conclusion ASIR significantly decreased the subjectively assessed homogeneity of the left ventricular lumen and increased the objectively measured noise compared to FBP. Considering these results, ASIR at a reduced radiation dose should be implemented with caution.

Influence of adaptive statistical iterative reconstruction algorithm on image quality in coronary computed tomography angiography

Background

Coronary computed tomography angiography (CCTA) requires high spatial and temporal resolution, increased low contrast resolution for the assessment of coronary artery stenosis, plaque detection, and/or non-coronary pathology. Therefore, new reconstruction algorithms, particularly iterative reconstruction (IR) techniques, have been developed in an attempt to improve image quality with no cost in radiation exposure.

Purpose

To evaluate whether adaptive statistical iterative reconstruction (ASIR) enhances perceived image quality in CCTA compared to filtered back projection (FBP).

Material and Methods

Thirty patients underwent CCTA due to suspected coronary artery disease. Images were reconstructed using FBP, 30% ASIR, and 60% ASIR. Ninety image sets were evaluated by five observers using the subjective visual grading analysis (VGA) and assessed by proportional odds modeling. Objective quality assessment (contrast, noise, and the contrast-to-noise ratio [CNR]) was analyzed with linear mixed effects modeling on log-transformed data. The need for ethical approval was waived by the local ethics committee as the study only involved anonymously collected clinical data.

Results

VGA showed significant improvements in sharpness by comparing FBP with ASIR, resulting in odds ratios of 1.54 for 30% ASIR and 1.89 for 60% ASIR (P = 0.004). The objective measures showed significant differences between FBP and 60% ASIR (P < 0.0001) for noise, with an estimated ratio of 0.82, and for CNR, with an estimated ratio of 1.26.

Conclusion

ASIR improved the subjective image quality of parameter sharpness and, objectively, reduced noise and increased CNR.

Analysis and compensation for the effect of the catheter position on image intensities in intravascular optical coherence tomography

Intravascular optical coherence tomography (IVOCT) is an imaging technique that is used to analyze the underlying cause of cardiovascular disease. Because a catheter is used during imaging, the intensities can be affected by the catheter position. This work aims to analyze the effect of the catheter position on IVOCT image intensities and to propose a compensation method to minimize this effect in order to improve the visualization and the automatic analysis of IVOCT images. The effect of catheter position is modeled with respect to the distance between the catheter and the arterial wall (distance-dependent factor) and the incident angle onto the arterial wall (angle-dependent factor). A light transmission model incorporating both factors is introduced. On the basis of this model, the interaction effect of both factors is estimated with a hierarchical multivariant linear regression model. Statistical analysis shows that IVOCT intensities are significantly affected by both factors with p<0.001, as either aspect increases the intensity decreases. This effect differs for different pullbacks. The regression results were used to compensate for this effect. Experiments show that the proposed compensation method can improve the performance of the automatic bioresorbable vascular scaffold strut detection.

First experiences with model based iterative reconstructions influence on quantitative plaque volume and intensity measurements in coronary computed tomography angiography

PURPOSE

Investigate the influence of adaptive statistical iterative reconstruction (ASIR) and the model-based IR (Veo) reconstruction algorithm in coronary computed tomography angiography (CCTA) images on quantitative measurements in coronary arteries for plaque volumes and intensities.

METHODS

Three patients had three independent dose reduced CCTA performed and reconstructed with 30% ASIR (CTDI_vol at 6.7 mGy), 60% ASIR (CTDI_vol 4.3 mGy) and Veo (CTDI_vol at 1.9 mGy). Coronary plaque analysis was performed for each measured CCTA volumes, plaque burden and intensities.

RESULTS

Plaque volume and plaque burden show a decreasing tendency from ASIR to Veo as median volume for ASIR is 314 mm³ and 337 mm³-252 mm³ for Veo and plaque burden is 42% and 44% for ASIR to 39% for Veo. The lumen and vessel volume decrease slightly from 30% ASIR to 60% ASIR with 498 mm³-391 mm³ for lumen volume and vessel volume from 939 mm³ to 830 mm³. The intensities did not change overall between the different reconstructions for either lumen or plaque.

CONCLUSION

We found a tendency of decreasing plaque volumes and plaque burden but no change in intensities with the use of low dose Veo CCTA (1.9 mGy) compared to dose reduced ASIR CCTA (6.7 mGy & 4.3 mGy), although more studies are warranted.

New developed DR detector performs radiographs of hand, pelvic and premature chest anatomies at a lower radiation dose and/or a higher image quality

A newly developed Digital Radiography (DR) detector has smaller pixel size and higher fill factor than earlier detector models. These technical advantages should theoretically lead to higher sensitivity and higher spatial resolution, thus making dose reduction possible without scarifying image quality compared to previous DR detector versions. To examine whether the newly developed Canon CXDI-70C DR detector provides an improved image quality and/or allows for dose reductions in hand and pelvic bone examinations as well as premature chest examinations, compared to the previous (CXDI-55C) DR detector version. A total of 450 images of a technical Contrast-Detail phantom were imaged on a DR system employing various kVp and mAs settings, providing an objective image quality assessment. In addition, 450 images of anthropomorphic phantoms were taken and analyzed by three specialized radiologists using Visual Grading Analysis (VGA). The results from the technical phantom studies showed that the image quality expressed as IQFINV values was on average approximately 45 % higher with the CXDI-70C detector compared to the CXDI-55C detector. Consistently, the VGA results from the anatomical phantom studies indicated that by using the CXDI-70C detector, diagnostic image quality could be maintained at a dose reduction of in average 30 %, depending on anatomy and kVp level. This indicates that the CXDI-70C detector is significantly more sensitive than the previous model, and supports a better clinical image quality. By using the newly developed DR detector a significant dose reduction is possible while maintaining image quality.

Digital radiography: optimization of image quality and dose using multi-frequency software

BACKGROUND

New developments in processing of digital radiographs (DR), including multi-frequency processing (MFP), allow optimization of image quality and radiation dose. This is particularly promising in children as they are believed to be more sensitive to ionizing radiation than adults.

OBJECTIVE

To examine whether the use of MFP software reduces the radiation dose without compromising quality at DR of the femur in 5-year-old-equivalent anthropomorphic and technical phantoms.

MATERIALS AND METHODS

A total of 110 images of an anthropomorphic phantom were imaged on a DR system (Canon DR with CXDI-50 C detector and MLT[S] software) and analyzed by three pediatric radiologists using Visual Grading Analysis. In addition, 3,500 images taken of a technical contrast-detail phantom (CDRAD 2.0) provide an objective image-quality assessment.

RESULTS

Optimal image-quality was maintained at a dose reduction of 61% with MLT(S) optimized images. Even for images of diagnostic quality, MLT(S) provided a dose reduction of 88% as compared to the reference image. Software impact on image quality was found significant for dose (mAs), dynamic range dark region and frequency band.

CONCLUSION

By optimizing image processing parameters, a significant dose reduction is possible without significant loss of image quality.