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OPTIMAX 2017 Radiation dose, image quality optimisation, the use of new technology in medical imaging

Comparative analysis of radiation dose and low contrast detail detectability using routine paediatric chest radiography protocols

OBJECTIVES: To compare low contrast detail (LCD) detectability and radiation dose for routine paediatric chest X-ray (CXR) imaging protocols among various hospitals.METHODS: CDRAD 2.0 phantom and medical grade polymethyl methacrylate (PMMA) slabs were used to simulate the chest region of four different paediatric age groups. Radiographic acquisitions were undertaken on 17 X-ray machines located in eight hospitals using their existing CXR protocols. LCD detectability represented by image quality figure inverse (IQF inv) was measured physically using the CDRAD analyser software. Incident air kerma (IAK) measurements were obtained using a solid-state dosimeter. RESULTS: The range of IQF inv, between and within the hospitals, was 1.40-4.44 and 1.52-2.18, respectively for neonates; 0.96-4.73 and 2.33-4.73 for a 1-year old; 0.87-1.81 and 0.98-1.46 for a 5-year old and 0.90-2.39 and 1.27-2.39 for a 10-year old. The range of IAK, between and within the hospitals, was 8.56-52.62 μGy and 21.79-52.62 μGy, respectively for neonates; 5.44-82.82 μGy and 36.78-82.82 μGy for a 1-year old; 10.97-59.22 μGy and 11.75-52.94 μGy for a 5-year old and 13.97-100.77 μGy and 35.72-100.77 μGy for a 10-year old. CONCLUSIONS: Results show considerable variation, between and within hospitals, in the LCD detectability and IAK. Further radiation dose optimisation for the four paediatric age groups, especially in hospitals /X-ray rooms with low LCD detectability and high IAK, are required.

Analysis of radiation exposure data from common radiological procedures in Dutch hospitals

INTRODUCTION: In the Netherlands, Diagnostic Reference Levels (DRLs) have not been based on a national survey as proposed by ICRP. Instead, local exposure data, expert judgment and the international scientific literature were used as sources. This study investigated whether the current DRLs are reasonable for Dutch radiological practice.METHODS: A national project was set up, in which radiography students carried out dose measurements in hospitals supervised by medical physicists. The project ran from 2014 to 2017 and dose values were analysed for a trend over time. In the absence of such a trend, the joint yearly data sets were considered a single data set and were analysed together. In this way the national project mimicked a national survey.RESULTS: For six out of eleven radiological procedures enough data was collected for further analysis. In the first step of the analysis no trend was found over time for any of these procedures. In the second step the joint analysis lead to suggestions for five new DRL values that are far below the current ones. The new DRLs are based on the 75 percentile values of the distributions of all dose data per procedure.CONCLUSION: The results show that the current DRLs are too high for five of the six procedures that have been analysed. For the other five procedures more data needs to be collected. Moreover, the mean weights of the patients are higher than expected. This introduces bias when these are not recorded and the mean weight is assumed to be 77 kg.IMPLICATIONS FOR PRACTICE: The current checking of doses for compliance with the DRLs needs to be changed. Both the procedure (regarding weights) and the values of the DRLs should be updated.

Impact of gonad shielding for AP pelvis on dose and image quality on different female sizes: A phantom study

Introduction: In clinical practice AP pelvis standard protocols are suitable for average size patients. However, as the average body size has increased over the past decades, radiographers have had to improve their practice in order to ensure that adequate image quality with minimal radiation dose to the patient is achieved. Gonad shielding has been found to be an effective way to reduce the radiation dose to the ovaries. However, the effect of increased body size, or fat thickness, in combination with gonad shielding is unclear. The goal of the study was to investigate the impact of gonad shielding in a phantom of adult female stature with increasing fat thicknesses on SNR (as a measure for image quality) and dose for AP pelvis examination. Methods: An adult Alderson female pelvis phantom was imaged with a variety of fat thickness categories as a representation of increasing BMI. 72 images were acquired using both AEC and manual exposure with and without gonad shielding. The radiation dose to the ovaries was measured using a MOSFET system. The relationship between fat thickness, SNR and dose when the AP pelvis was performed with and without shielding was investigated using the Wilcoxon signed rank test. P-values < 0.05 were considered to be statistically significant. Results: Ovary dose and SNR remained constant despite the use of gonad shielding while introducing fat layers. Conclusion: The ovary dose did not increase with an increase of fat thickness and the image quality was not altered. Implications for practice: Based on this phantom study it can be suggested that obese patients can expect the same image quality as average patients while respecting ALARA principle when using adequate protocols.

To Game or Not to Game? Efficacy of Using Tablet Games in Vocabulary Intervention for Children with DLD

The adoption of tablets by young children has raised enthusiasm and concern among speech and language pathologists. This study investigated whether tablet games can be used as effectively as real play objects in vocabulary intervention for children with developmental language disorder (DLD). A randomized, controlled non-inferiority trial was conducted with 70 3-year-old children with DLD. The novel intervention group (n = 35) received 12 10-min scripted intervention sessions with symbolic play using a tablet game spread out over 8–9 weeks. The standard intervention group (n = 35) received the same amount of intervention with real objects using the same vocabulary scripts. In each session, children were exposed to 22 target words. The primary outcome was the number of new target words learned. This was measured using a picture selection task including 22 target words and 22 control words at 3 time intervals: before the intervention, immediately post-intervention, and 5 weeks later. In both intervention groups, the children learned significantly more target words than control words. No significant differences in gains between the two intervention conditions were found. This study provides evidence that vocabulary intervention for toddlers with DLD using a tablet game is equally as effective as an intervention using real objects.

Physical rehabilitation interventions in children with acquired brain injury

AIM: To synthesize the evidence about the characteristics (frequency, intensity, time, type) and effects of physical rehabilitation interventions on functional recovery and performance in daily functioning in children and young people with acquired brain injury (ABI), including traumatic brain injuries (TBI) and non-TBI, during the subacute rehabilitation phase.METHOD: Using scoping review methodology, a systematic literature search was performed using four databases. Articles were screened by title and abstract and data from eligible studies were extracted for synthesis.RESULTS: Nine of 3009 studies were included. The results demonstrated a variety of intervention characteristics: frequency varied between 1 and 7 days per week; time of intervention varied between 25 minutes and 6 hours a day; intervention types were specified in seven studies; and none of the included studies reported details of intensity of intervention. All studies reported positive results on the International Classification of Functioning, Disability and Health: Children and Youth (ICF-CY) levels of body function and activities after the intervention period, with study designs of included studies being cohort studies without concurrent controls (n=7) or case reports (n=2).INTERPRETATION: Inconsistency in results hampers generalizability to guide clinical practice. Physical interventions during subacute rehabilitation have potential to improve functional recovery with intervention characteristics as an important factor influencing its effectiveness. Future well-designed studies are indicated to gain knowledge and optimize rehabilitation practice in paediatric ABI and high-quality research including outcomes across all ICF-CY domains is needed.