Ethical and societal aspects of radiological protection for offspring and next generations.

PURPOSE: Over the last decade or so, ethical and societal aspects of radiological protection have received increasing attention. This is also reflected in the publications of the International Commission on Radiological Protection (ICRP). The current paper aims at identifying relevant ethical and societal topics which should receive attention in the context of radiological protection for offspring and next generations. MATERIALS AND METHODS: We present a non-comprehensive review of the subject, based on presentation made at an ICRP workshop in Budapest in 2022. We first discuss the ethical values promoted by ICRP, and the application of these values in cases of (potential) pre-conceptual and prenatal radiation exposures. We then consider experience gained after the Fukushima accident indicating particular societal concerns about the health effects of such exposures. RESULTS AND CONCLUSIONS: Beneficence/non-maleficence, prudence, justice and dignity, the "core values" of the system of radiological protection have special roles to play when heritable and/or in utero effects are to be considered. Prudence, in particular, must be taken account of in view of the fact that solid scientific data in humans are largely lacking in this area, and it is necessary to rely on insights from animal experiments as well as theoretical considerations. As regards societal considerations, the perception of risk among (potentially) affected populations needs to be taken seriously. Accountability, transparency, and inclusivity, the "procedural values" promoted by ICRP for the practical implementation of the system of radiological protection play a central role in overcoming skepticism and creating trust. Stakeholder involvement should emphasize cooperation and dialogue, which allows for the joint evaluation of an exposure situation by experts and affected people.

Evaluating the genetic consequences of population subdivision as it unfolds and how to best mitigate them: A rare story about koalas.

The genetic consequences of the subdivision of populations are regarded as significant to long-term evolution, and research has shown that the scale and speed at which this is now occurring is critically reducing the adaptive potential of most species which inhabit human-impacted landscapes. Here, we provide a rare and, to our knowledge, the first analysis of this process while it is happening and demonstrate a method of evaluating the effect of mitigation measures such as fauna crossings. We did this by using an extensive genetic data set collected from a koala population which was intensely monitored during the construction of linear transport infrastructure which resulted in the subdivision of their population. First, we found that both allelic richness and effective population size decreased through the process of population subdivision. Second, we predicted the extent to which genetic drift could impact genetic diversity over time and showed that after only 10 generations the resulting two subdivided populations could experience between 12% and 69% loss in genetic diversity. Lastly, using forward simulations we estimated that a minimum of eight koalas would need to disperse from each side of the subdivision per generation to maintain genetic connectivity close to zero but that 16 koalas would ensure that both genetic connectivity and diversity remained unchanged. These results have important consequences for the genetic management of species in human-impacted landscapes by showing which genetic metrics are best to identify immediate loss in genetic diversity and how to evaluate the effectiveness of any mitigation measures.

The injury patterns, management and outcomes of retroperitoneal haemorrhage caused by lumbar arterial bleeding at a Level-1 Trauma Centre: A 10-year retrospective review.

PURPOSE: Haemorrhagic shock remains a leading preventable cause of death amongst trauma patients. Failure to identify retroperitoneal haemorrhage (RPH) can lead to irreversible haemorrhagic shock. The arteries of the middle retroperitoneal region (i.e., the 1st to 4th lumbar arteries) are complicit in haemorrhage into the retroperitoneal space. However, predictive injury patterns and subsequent management implications of haemorrhage secondary to bleeding of these arteries is lacking. MATERIALS AND METHODS: We performed a retrospective cohort study of patients diagnosed with retroperitoneal haemorrhage who presented to our Level-1 Trauma Centre (2009-2019). We described the associated injuries, management and outcomes relating to haemorrhage of lumbar arteries (L1-4) from this cohort to assess risk and management priorities in non-cavitary haemorrhage compared to RPH due to other causes. RESULTS: Haemorrhage of the lumbar arteries (LA) is associated with a higher proportion of lumbar transverse process (TP) fractures. Bleeding from branches of these vessels is associated with lower systolic blood pressure, increased incidence of massive transfusion, higher shock index, and a higher Injury Severity Score (ISS). A higher proportion of patients in the LA group underwent angioembolisation when compared to other causes of RPH. CONCLUSION: This study highlights the injury patterns, particularly TP fractures, in the prediction, early detection and management of haemorrhage from the lumbar arteries (L1-4). Compared to other causes of RPH, bleeding of the LA responds to early, aggressive haemorrhage control through angioembolisation. These injuries are likely best treated in Level-1 or Level-2 trauma facilities that are equipped with angioembolisation facilities or hybrid theatres to facilitate early identification and management of thoracolumbar bleeds.

Feasibility study of computational occupational dosimetry: evaluating a proof-of-concept in an endovascular and interventional cardiology setting.

Individual monitoring of radiation workers is essential to ensure compliance with legal dose limits and to ensure that doses are As Low As Reasonably Achievable. However, large uncertainties still exist in personal dosimetry and there are issues with compliance and incorrect wearing of dosimeters. The objective of the PODIUM (Personal Online Dosimetry Using Computational Methods) project was to improve personal dosimetry by an innovative approach: the development of an online dosimetry application based on computer simulations without the use of physical dosimeters. Occupational doses were calculated based on the use of camera tracking devices, flexible individualised phantoms and data from the radiation source. When combined with fast Monte Carlo simulation codes, the aim was to perform personal dosimetry in real-time. A key component of the PODIUM project was to assess and validate the methodology in interventional radiology workplaces where improvements in dosimetry are needed. This paper describes the feasibility of implementing the PODIUM approach in a clinical setting. Validation was carried out using dosimeters worn by Vascular Surgeons and Interventional Cardiologists during patient procedures at a hospital in Ireland. Our preliminary results from this feasibility study show acceptable differences of the order of 40% between calculated and measured staff doses, in terms of the personal dose equivalent quantity Hp(10), however there is a greater deviation for more complex cases and improvements are needed. The challenges of using the system in busy interventional rooms have informed the future needs and applicability of PODIUM. The availability of an online personal dosimetry application has the potential to overcome problems that arise from the use of current dosimeters. In addition, it should increase awareness of radiation protection among staff. Some limitations remain and a second phase of development would be required to bring the PODIUM method into operation in a hospital setting. However, an early prototype system has been tested in a clinical setting and the results from this two-year proof-of-concept PODIUM project are very promising for future development.

Personal dosimetry for positron emitters, and occupational exposures from clinical use of gallium-68.

The current status and issues regarding positron dosimetry in nuclear medicine are summarized. The suitability of the United Kingdom Health Security Agency extremity and eye beta-gamma personal thermoluminescence dosemeters are then considered. Monte Carlo modelling is performed to determine their responses and derive sets of calibration factors, along withHp(0.07) andHp(3) conversion coefficients, for carbon-11, nitrogen-13, oxygen-15, fluorine-18 and gallium-68 sources, which are commonly used in positron emission tomography (PET) computed tomography; data for these isotopes is assumed extrapolatable to other positron sources. It is found that the dosemeters are adequate for assessing exposures to PET radionuclides, even if their routine calibrations to caesium-137 were maintained. An idealized set of measurements representing gallium-68 exposure scenarios is then described, including reproducible mock-ups of individuals manipulating vials and syringes. Finally, a short case-study is presented that explores occupational doses during routine clinical use of gallium-68. The extremity dosemeter results demonstrated significant variations dependent upon the exposure conditions, with some seen to be comparatively large; whole-body and eye dose rates per activity were found to be lower. The importance of routine dose monitoring of workers is emphasized, with the need for a longer-termed follow-up study demonstrated.

The mortality rate from self-harm in Iran.

BACKGROUND: Self-harm-related death is one of the most unfortunate, tragic, and regrettable types of death owing to injuries with a variety of socio-economic and cultural causes. The study aimed to determine the trend in the mortality of self-harm by sex and age at national and provincial levels in Iran over a period of 26 years. METHODS: The Iran Death Registration System (DRS), cemetery databanks in Tehran and Esfahan, and the national population and housing censuses of Iran were used for this study. Using a growth model, the population was estimated in the age groups. Incompleteness, misalignment, and misclassification in the DRS were all considered and addressed accordingly. We used a spatio-temporal and Gaussian process regression model to estimate mortality rates in children and adults. RESULTS: Over the study period, 67,670 deaths were estimated owing to self-harm across the country. The overall age-standardized mortality rate decreased from 4.32 per 100,000 (95% unit interface (UI): 3.25-5.75) to 2.78 (2.15-3.59) per 100,000 between 1990 and 2015, a reduction of approximately 35.65%. The M/F ratio was 2.03:1 with an annual percent change of -2.38% and -1.37% for women and men, respectively. The annual self-harm mortality rate was higher among individuals aged 15-24 years, as well as it was more in men during the study period. CONCLUSION: Mortality from self-harm has declined over the study period in Iran. Higher rates in men and in population aged 15-24 years, with considerable variation by province, were the distinguishing features of self-harm. Iran needs to improve monitoring through a comprehensive multisectoral strategy; and most importantly, provide timely, effective and low-cost preventive interventions.

A checklist for trauma quality improvement meetings: A process improvement study.

BACKGROUND: Each year approximately five million people die from injuries. In countries where systems of trauma care have been introduced, death and disability have decreased. A major component of developed trauma systems is a trauma quality improvement (TQI) program and trauma quality improvement meeting (TQIM). Effective TQIMs improve trauma care by identifying and fixing problems. But globally, TQIMs are absent or unstructured in most hospitals providing trauma care. The aim of this study was to implement and evaluate a checklist for a structured TQIM. METHODS: This project was conducted as a prospective before-and-after study in four major trauma centres in India. The intervention was the introduction of a structured TQIM using a checklist, introduced with a workshop. This workshop was based on the World Health Organization (WHO) TQI Programs short course and resources, plus the developed TQIM checklist. Pre- and post-intervention data collection occurred at all meetings in which cases of trauma death were discussed. The primary outcome was TQIM Checklist compliance, defined by the discussion of, and agreement upon each of the following: preventability of death, identification of opportunities to improve care and corrective actions and a plan for closing the loop. RESULTS: There were 34 meetings in each phase, with 99 cases brought to the pre-intervention phase and 125 cases brought to the post-intervention phase. There was an increase in the proportion of cases brought to the meeting for which preventability of death was discussed (from 94% to 100%, p = 0.007) and agreed (from 7 to 19%, OR 3.7; 95% CI:1.4-9.4, p = 0.004) and for which a plan for closing the loop was discussed (from 2% to 18%, OR 10.9; 95% CI:2.5-47.6, p < 0.001) and agreed (from 2% to 18%, OR 10.9; 95% CI:2.5-47.6, p < 0.001). CONCLUSION: This study developed, implemented and evaluated a TQIM Checklist for improving TQIM processes. The introduction of a TQIM Checklist, with training, into four Indian trauma centres, led to more structured TQIMs, including increased discussion and agreement on preventability of death and plans for loop closure. A TQIM Checklist should be considered for all centres managing trauma patients.

Trend of fatal poisoning at national and provincial levels in Iran from 1990 to 2015.

OBJECTIVES: Comprehensive and up-to-date data on fatal injury trends are critical to identify challenges and plan priority setting. This study provides a comprehensive assessment of poisoning mortality trends across Iran. STUDY DESIGN: The data were gathered from various resources, including death registration systems, cemetery databases of Tehran and Esfahan, the Demographic and Health Survey of 2000, and three rounds of national population and housing censuses. METHODS: After addressing incompleteness for child and adult death data separately and using a spatio-temporal model and Gaussian process regression, the level and trend of child and adult mortality were estimated. For estimating cause-specific mortality, the cause fraction was calculated and applied to the level and trend of death. RESULTS: From 1990 to 2015, 40,586 deaths due to poisoning were estimated across the country. The poisoning-related age-standardized death rate per 100,000 was estimated to have changed from 3.08 (95% uncertainty interval [UI]: 2.32-4.11) in 1990 to 0.96 (95% UI: 0.73-1.25) in 2015, and the male/female ratio was 1.35 during 25 years of study with an annual percentage change of -5.4% and -4.0% for women and men, respectively. The annual mortality rate was higher among children younger than 5 years and the elderly population (≥70 years) in the study period. CONCLUSIONS: This study showed that mortality from poisoning declined in Iran over the period from 1990 to 2015 and varied by province. Understanding the reasons for the differences of poisoning mortality by province will help in developing and implementing measures to reduce this burden in Iran.

Internet use among young people with and without mental health difficulties.

OBJECTIVES: Research regarding adolescent internet use and mental health is sparse. However, awareness of a young person's internet use is becoming increasingly recognised as an important element of clinical assessment and intervention, and requires the development of an evidence base. The aim of the present study was to better understand the internet use of young people experiencing mental health difficulties and to contrast it with those who currently report no concerns. METHOD: In total, 299 young people aged 12-19 years, across a continuum of mental health difficulties, completed an online survey measuring internet use and related experiences. Young people were assigned to four groups: (a) attending inpatient services; (b) attending outpatient services; (c) a community group with mental health concerns and no clinical support; and (d) a regular community group. RESULTS: Those in the inpatient and outpatient groups visited more potentially harmful websites. Young people attending inpatient and outpatient services showed aspects of both more risky and less risky use. The community group reporting no mental health difficulties showed least risky use. The group experiencing difficulties but not receiving support showed consistently high risky use, suggesting this is a particularly vulnerable group. CONCLUSIONS: Despite methodological limitations, findings suggest that those with mental health difficulties may experience more of the risks and fewer of the benefits offered by the internet. Though further research is needed to clarify these findings, clinicians should consider routine assessment of Internet use when planning interventions for young people experiencing mental health difficulties.

Management of haemodynamically stable patients with penetrating abdominal stab injuries: review of practice at an Australian major trauma centre.

INTRODUCTION: The management of haemodynamically stable patients who present following a penetrating abdominal injury (PAI) remains variable between mandatory surgical exploration and more selective non-operative approaches. The primary aim of this study was to assess compliance with an algorithm guiding selective non-operative management of haemodynamically stable patients with PAI. The secondary aim was to examine the association between compliance and unnecessary laparotomies. METHODS: This was a retrospective cohort study involving all patients with PAI that presented to a major trauma centre from January 2007 to December 2011. Data were extracted from the trauma registry and patients' electronic medical records. RESULTS: There were 189 patients included in the study, of which 79 (41.8 %) patients complied with the algorithm. The laparotomy rate in the setting of algorithm compliance was significantly lower than algorithm non-compliance (12.7 vs. 68.2 %; p < 0.01) as were unnecessary laparotomy rates (0 vs. 33.3 %; p = 0.03). CONCLUSION: Among haemodynamically stable patients presenting with PAI, compliance with an algorithm guiding selective non-operative management was low, but associated with lower laparotomy and lower unnecessary laparotomy rates. Improved compliance with algorithms directed towards selective non-operative management of PAI should be encouraged with stringent vigilance towards patient safety.

Innovations in the Use of Interactive Technology to Support Weight Management.

New and emerging mobile technologies are providing unprecedented possibilities for understanding and intervening on obesity-related behaviors in real time. However, the mobile health (mHealth) field has yet to catch up with the fast-paced development of technology. Current mHealth efforts in weight management still tend to focus mainly on short message systems (SMS) interventions, rather than taking advantage of real-time sensing to develop just-in-time adaptive interventions (JITAIs). This paper will give an overview of the current technology landscape for sensing and intervening on three behaviors that are central to weight management: diet, physical activity, and sleep. Then five studies that really dig into the possibilities that these new technologies afford will be showcased. We conclude with a discussion of hurdles that mHealth obesity research has yet to overcome and a future-facing discussion.

Occupational radiation dose to eyes from interventional radiology procedures in light of the new eye lens dose limit from the International Commission on Radiological Protection.

OBJECTIVE: In 2011, the International Commission on Radiological Protection (ICRP) recommended a substantial reduction in the equivalent dose limit for the lens of the eye, in line with a reduced threshold of absorbed dose for radiation-induced cataracts. This is of particular relevance in interventional radiology (IR) where it is well established that staff doses can be significant, however, there is a lack of data on IR eye doses in terms of Hp(3). Hp(3) is the personal dose equivalent at a depth of 3 mm in soft tissue and is used for measuring lens dose. We aimed to obtain a reliable estimate of eye dose to IR operators. METHODS: Lens doses were measured for four interventional radiologists over a 3-month period using dosemeters specifically designed to measure Hp(3). RESULTS: Based on their typical workloads, two of the four interventional radiologists would exceed the new ICRP dose limit with annual estimated doses of 31 and 45 mSv to their left eye. These results are for an "unprotected" eye, and for IR staff who routinely wear lead glasses, the dose beneath the glasses is likely to be significantly lower. Staff eye dose normalized to patient kerma-area product and eye dose per procedure have been included in the analysis. CONCLUSION: Eye doses to IR operators have been established using a dedicated Hp(3) dosemeter. Estimated annual doses have the potential to exceed the new ICRP limit. ADVANCES IN KNOWLEDGE: We have estimated lens dose to interventional radiologists in terms of Hp(3) for the first time in an Irish hospital setting.

Young people in drug treatment in Ireland: their views on substance use aetiology, trajectory, parents' role in substance use and coping skills.

OBJECTIVES: The aim of the current study was to gain insight into the process of initiation and progression to problematic use among young people who reach clinically significant levels of substance use requiring treatment. METHOD: Twenty young people, aged between 15 and 19 years from two different drug treatment centres in Ireland were interviewed regarding their views on their pathway into substance use, their progress to more problematic use, their perception of their parents' role, if any, in their trajectory and their typical coping style before treatment. Content analysis was conducted on the resulting narratives. RESULTS: The use of substances to cope with life stressors emerged as a prominent theme at initial and problematic stages of use. Multiple maladaptive coping approaches were reported. Both direct and indirect influences from parents in their substance use problem were cited. However, some participants reported that parents had no causal role in their substance use trajectory, in particular regarding mothers. CONCLUSIONS: The current findings suggest that substance misuse is a multi-determined problem and a number of intervention strategies are suggested to delay onset and related harms associated with adolescent substance use.

A procedural check list for pleural decompression and intercostal catheter insertion for adult major trauma.

BACKGROUND: Intercostal catheter (ICC) insertion is the standard pleural decompression and drainage technique for blunt and penetrating traumatic injury. Potentially high complication rates are associated with the procedure, with the literature quoting over 20% in some cases (1-4). Empyema in particular is a serious complication. Risk adverse industries such as the airline industry and military services regularly employ checklists to standardise performance and decrease human errors. The use of checklists in medical practice is exemplified by introduction of the WHO Surgical Safety checklist. METHODS: The Alfred Hospital in Melbourne, Australia is an Adult Level 1 Trauma Centre. In August 2009 The Alfred Trauma Service introduced an evidence-based checklist system for the insertion of ICCs, combined with standardised formal training for resident medical staff, in an attempt to minimise the incidence of ICC related empyema. RESULTS: Between January 2003 and July 2009 the incidence of empyema was 1.44% (29 in 2009 insertions). This decreased to 0.57% between August 2009 and December 2011 (6 in 1060 insertions) when the measures described above were introduced [p=0.038 Fisher's exact test, 2-tailed]. CONCLUSION: Quality control checklists - such as the ICC checklist described - are a sensible and functional means to standardise practice, to decrease procedural error and to reduce complication rates during trauma resuscitation.

Eye dose monitoring of PET/CT workers.

OBJECTIVE: The objective of the study was to measure eye dose [Hp(3)] to workers in a busy positron emission tomography (PET)/CT centre. Doses were compared with the proposed new annual dose limit of 20 mSv. METHODS: We used a newly designed dosemeter to measure eye dose [Hp(3)]. Eye dosemeters were worn with an adjustable headband, with the dosemeter positioned adjacent to the left eye. The whole-body dose was also recorded using electronic personal dosemeter (EPD® Mk2; Thermo Electron Corporation, Waltham, MA). Exposed staff included radiographers, nurses and healthcare assistants. RESULTS: The radiographers received the highest exposure of the staff groups studied, with one radiographer receiving an exposure of 0.5 mSv over the 3-month survey period. The estimated maximum eye dose for 1 year is approximately 2 mSv. The numeric value for eye dose was compared with the numeric value for personal dose equivalent to see if one could be used as an indicator for the other. From our data, a conservative estimate of eye dose Hp(3) (mSv) can be made as being up to approximately twice the numeric value for whole-body dose [Hp(10)] (mSv). CONCLUSION: Eye dose was found to be well within the new proposed annual limit at our PET/CT centre. Routine whole-body dose measurements may be a useful starting point for assessing whether eye dose monitoring should be prioritized in a PET facility. ADVANCES IN KNOWLEDGE: Following the proposal of a reduced eye dose limit, this article provides new measurement data on staff eye doses for PET/CT workers.

Mindfulness-based interventions for obesity-related eating behaviours: a literature review.

Mindfulness-based interventions (MBIs) targeting eating behaviours have gained popularity in recent years. A literature review was conducted to determine the effectiveness of MBIs for treating obesity-related eating behaviours, such as binge eating, emotional eating and external eating. A search protocol was conducted using the online databases Google Scholar, PubMed, PsycINFO and Ovid Healthstar. Papers were required to meet the following criteria to be included in this review: (i) describe a MBI or the use of mindfulness exercises as part of an intervention; (ii) include at least one obesity-related eating behaviour as an outcome; (iii) include quantitative outcomes; and (iv) be published in English in a peer-reviewed journal. A total of N = 21 papers were included in this review. Interventions used a variety of approaches to implement mindfulness training, including combined mindfulness and cognitive behavioural therapies, mindfulness-based stress reduction, acceptance-based therapies, mindful eating programmes, and combinations of mindfulness exercises. Targeted eating behaviour outcomes included binge eating, emotional eating, external eating and dietary intake. Eighteen (86%) of the reviewed studies reported improvements in the targeted eating behaviours. Overall, the results of this first review on the topic support the efficacy of MBIs for changing obesity-related eating behaviours, specifically binge eating, emotional eating and external eating.

The accuracy of adult limb radiograph interpretation by emergency nurse practitioners: A prospective comparative study.

BACKGROUND: One of the extensions to practice for the emergency nurse practitioner role is to appropriately order and interpret radiographs in the emergency department. OBJECTIVE: The aim of the study was to compare the accuracy in interpreting isolated adult limb radiographs between emergency nurse practitioners and emergency physicians. DESIGN: A prospective comparative study was undertaken. SETTING: Emergency department in a large metropolitan hospital. PARTICIPANTS: 200 adult patients with isolated limb injuries were consented. METHODS: Six emergency nurse practitioners and ten emergency physicians participated. One emergency physician and emergency nurse practitioner independently clinically assessed each patient, determined the need for radiograph and separately recorded their interpretation of the radiograph as either definite fracture, no fracture or possible fracture. A single consultant radiologist reviewed each radiograph and their interpretation was seen as the gold standard. The sensitivity and specificity of emergency physicians and emergency nurse practitioners were calculated. To measure the level of agreement between the two-clinician groups, the weighted Kappa statistic was used. RESULTS: The sensitivity for the emergency nurse practitioners was 91% and 88% for the emergency physicians. The specificity for the emergency nurse practitioners was 85% and for the emergency physicians 91%. The weighted Kappa on the presence of a fracture between the emergency nurse practitioners and emergency physicians was 0.83. CONCLUSIONS: This study validates the clinical and diagnostic skills of emergency nurse practitioners assessed in the interpretation of isolated adult limb injury radiographs.

Occupational radiation dose to eyes from endoscopic retrograde cholangiopancreatography procedures in light of the revised eye lens dose limit from the International Commission on Radiological Protection.

OBJECTIVE: Endoscopic retrograde cholangiopancreatography (ERCP) is a common procedure that combines the use of X-ray fluoroscopy and endoscopy for examination of the bile duct. Published data on ERCP doses are limited, including staff eye dose from ERCP. Occupational eye doses are of particular interest now as the International Commission on Radiological Protection (ICRP) has recommended a reduction in the dose limit to the lens of the eye. The aim of this study was to measure occupational eye doses obtained from ERCP procedures. METHODS: A new eye lens dosemeter (EYE-D(™), Radcard, Krakow, Poland) was used to measure the ERCP eye dose, H(p)(3), at two endoscopy departments in Ireland. A review of radiation protection practice at the two facilities was also carried out. RESULTS: The mean equivalent dose to the lens of the eye of a gastroenterologist is 0.01 mSv per ERCP procedure with an undercouch X-ray tube and 0.09 mSv per ERCP procedure with an overcouch X-ray tube. Staff eye dose normalised to patient kerma area product is also presented. CONCLUSION: Staff eye doses in ERCP have the potential to exceed the revised ICRP limit of 20 mSv per annum when an overcouch X-ray tube is used. The EYE-D dosemeter was found to be a convenient method for measuring lens dose. Eye doses in areas outside of radiology departments should be kept under review, particularly in light of the new ICRP eye dose limit. ADVANCES IN KNOWLEDGE: Occupational eye lens doses from ERCP procedures have been established using a new commercially available dedicated H(p)(3) dosemeter.

Comparison of clinical and physics scoring of PET images when image reconstruction parameters are varied.

In this study the quantitative and qualitative image quality (IQ) measurements with clinical judgement of IQ in positron emission tomography (PET) were compared. The limitations of IQ metrics and the proposed criteria of acceptability for PET scanners are discussed. Phantom and patient images were reconstructed using seven different iterative reconstruction protocols. For each reconstructed set of images, IQ was scored based both on the visual analysis and on the quantitative metrics. The quantitative physics metrics did not rank the reconstruction protocols in the same order as the clinicians' scoring of perceived IQ (R(s)=-0.54). Better agreement was achieved when comparing the clinical perception of IQ to the physicist's visual assessment of IQ in the phantom images (R(s)=+0.59). The closest agreement was seen between the quantitative physics metrics and the measurement of the standard uptake values (SUVs) in small tumours (R(s)=+0.92). Given the disparity between the clinical perception of IQ and the physics metrics a cautious approach to use of IQ measurements for determining suspension levels is warranted.

Doses measured using AEC on direct digital radiographic (DDR) X-rays systems: updated results with an RP 162 perspective.

As digital technology in diagnostic radiology systems becomes more prevalent, there is a need to provide comparative dose information for these new systems. This is needed in particular for testing the automatic exposure control (AEC) devices on direct digital radiography (DDR) systems as there is no consensus on the receptor dose level in the current guidelines. The new European Commission RP 162 document sets the suspension level for the 'verification of kerma at receptor entrance in computed radiography and DDR systems under AEC' as ≥10 µGy. This document also notes that alternate methodologies are acceptable, and may require adjustment in the suspension level if used. This study provides a range of typical doses under AEC for DDR systems, for a variety measurement methodologies, including that described in RP 162.