Analysing false-positive errors when Australian radiographers use preliminary image evaluation.

INTRODUCTION: Diagnostic errors in the emergency departments can have major implications on patient outcomes. Preliminary Image Evaluation (PIE) is a brief comment written by a radiographer describing an acute or traumatic pathology on a radiograph and can be used to complement referrer's image interpretation in the absence of the radiologist report. Currently, no studies exist that focus their analysis on false-positive (FP) errors in PIE. The purpose of this study was to investigate the regions of the body that cause the most FP errors and recognise other areas in image interpretation that may need additional attention. METHODS: A longitudinal retrospective clinical audit was conducted to determine the accuracy of radiographer PIE's over 5 years from January 2016 to December 2020. PIE's were compared to the radiologist report to assess for diagnostic accuracy. FP and unsure errors were further categorised by anatomical region and age. RESULTS: Over this period, a sample size of 11,090 PIE audits were included in the study demonstrating an overall PIE accuracy of 87.7%. Foot, ankle and chest regions caused the most FP errors, while ankle, shoulder and elbow caused the most unsure cases. 76% of the unsure cases were negative for any pathology when compared to the radiologist report. The paediatric population accounted for 21.3% of FP cases and 33.6% of unsure cases. CONCLUSION: Findings in this study should be used to tailor education specific to radiographer image interpretation. Improving radiography image interpretation skills can assist in improving referrer diagnostic accuracy, thus improving patient outcomes.

Experiences of embedding gender and sexuality diversity workshops in an undergraduate medical imaging curriculum.

This commentary describes some of the reported challenges of health participation for the gender- and sexuality-diverse (GSD) population, particularly related to medical imaging practice. The approach and student feedback of an undergraduate education initiative to support students in the delivery of culturally competent care are described. The experiences of delivery over a three-year period are reported, including the 2020 online delivery due to COVID-19 precautions. Student feedback demonstrates positive outcomes from the workshops and activities.

An analysis of radiographer preliminary image evaluation - A focus on common false negatives.

INTRODUCTION: Preliminary image evaluation (PIE) is a mechanism whereby radiographers provide a preliminary evaluation of whether pathology is present in their radiographs, typically acquired within the emergency department (ED). PIE provides referrers with a timely communication of pathology prior to the availability of a radiology report. The purpose of this study was to determine the most common radiographer PIE false-negative interpretations. METHODS: Each month over a two-year period, 100 PIEs of adult and paediatric patients were randomly reviewed in a metropolitan hospital ED. The radiographer's PIE was compared with the radiologist's report and categorised into basic quality indicators; true positive, true negative, false positive and false negative. The anatomical regions which most commonly indicated a false-negative interpretation were further analysed. RESULTS: 2402 cases were reviewed which resulted in an overall PIE accuracy of 88.7%. Wrists, hands, phalanges (upper), ankles, feet and phalanges (lower) reporting the highest false-negative or false-negative/true-positive interpretations (60/116). Of the 60 false-negative PIEs, 68 pathologies were identified. 41.1% (28/68) of the pathology not identified were in the phalanges. Within these regions, examinations with multiple injuries commonly reported false negatives (17/60). CONCLUSIONS: This study demonstrated the most common false-negative radiographer PIEs were within the upper and lower distal extremities. Specifically, the phalanges and examinations demonstrating multiple injuries reported high levels of misinterpretation. The misinterpretation in multi-injury examinations could be attributed to 'Subsequent Search Miss (SSM)' error. These results provide valuable insights into areas of emphasis when providing image interpretation education.

The proportion of computed tomography kidneys, ureters and bladder (CTKUB) scans that comply with scan extent protocol in an emergency department: a clinical audit and dose ramification study.

INTRODUCTION: To assess computed tomography kidneys, ureters and bladder (CTKUB) scan extent protocol compliance and associated doses in the Emergency Department (ED) of an Australian tertiary hospital. METHODS: A retrospective clinical audit of 150 consecutive ED CTKUB cases was completed. For each patient, scan extent compliance at the superior (kidneys) and inferior (pubic symphysis) borders, in reference to the protocol was recorded. Compliance and non-compliance (over-/under-scanning) was identified, described (superior/inferior), quantified (via IMPAX measurements) and recorded via a purpose-built audit tool. In addition, a PBU40 phantom was scanned to assess the percentage of dose (DLP) increase per centimetre of over-scanning to contextualise results. RESULTS: A notable non-compliance with department protocol was noted. Eight cases (5.3%) demonstrated overall CT scan extent compliance. The remaining 142 cases (94.7%) demonstrated some form of non-compliance; superiorly, inferiorly or both. Analysing the 150 superior and 150 inferior data points independently, the most common non-compliance was over-scanning at the kidneys by 4 cm to5 cm (19 cases, ~10% extra DLP) beyond tolerance and over-scanning inferiorly at the pubic symphysis by 1 cm to 2 cm (29 cases, ~6.4% extra DLP). Estimated dose increases of up to 35% to 45% were found when clinical audit results were simulated using a PBU40. CONCLUSIONS: Over-scanning is a predominant occurrence in CTKUB scans in this department. Reasons for over-scanning weren't investigated. It's anticipated this audit will lead to greater awareness of scan extent compliance and dose ramifications of non-compliance. The usage of more easily identified anatomical landmarks and a follow-up audit is suggested.

The use of virtual reality computed tomography simulation within a medical imaging and a radiation therapy undergraduate programme.

INTRODUCTION: The use of virtual reality (VR) simulation in the education of healthcare professionals has expanded into the field of medical radiation sciences. The purpose of this research was to report on the student experience of the integration of VR education for both medical imaging (MI) and radiation therapy (RT) students in learning computed tomography (CT) scanning. METHODS: A survey was performed to evaluate students' perceived confidence in performing diagnostic and planning CT scans in the clinical environment following VR CT simulation tutorials. Students from both MI and RT participated in providing quantitative and qualitative data. RESULTS: The MI students (n = 28) and RT students (n = 38) provided quantitative results linking their engagement (perceived usefulness, ease of use, enjoyment) with their perceived confidence. The 15 (54%) MI students who recorded a maximum engagement score had a mean confidence score 1.02 higher than the students not fully engaged (Fisher's exact test 14.549, P = 0.00). The results from the RT cohort revealed 68% of students agreed or strongly agreed to the addition of VR CT simulation helping in the learning of CT. CONCLUSION: It can be concluded that the integration of innovative learning opportunities such as VR CT simulation has the potential to increase student confidence and improve student preparation for the clinical environment.

An investigation into the effect of changing the computed tomography slice reconstruction interval on the spatial replication accuracy of three-dimensional printed anatomical models constructed by fused deposition modelling.

INTRODUCTION: Three-dimensional (3D) printed models can be constructed utilising computed tomography (CT) data. This project aimed to determine the effect of changing the slice reconstruction interval (SRI) on the spatial replication accuracy of 3D-printed anatomical models constructed by fused deposition modelling (FDM). METHODS: Three bovine vertebrae and an imaging phantom were imaged using a CT scanner. The Queensland State Government's Animal Care and Protection Act 2001 did not apply as no animals were harmed to carry out scientific activity. The data were reconstructed into SRIs of 0.1, 0.3, 0.5 and 1 mm and processed by software before 3D printing. Specimens and printed models were measured with calipers to calculate mean absolute error prior to statistical analysis. RESULTS: Mean absolute error from the original models for the 0.1, 0.3, 0.5 and 1 mm 3D-printed models was 0.592 ± 0.396 mm, 0.598 ± 0.479 mm, 0.712 ± 0.498 mm and 0.933 ± 0.457 mm, respectively. Paired t-tests (P < 0.05) indicated a statistically significant difference between all original specimens and corresponding 3D-printed models except the 0.1 mm vertebrae 2 (P = 0.061), 0.3 mm phantom 1 (P = 0.209) and 0.3 mm vertebrae 2 (P = 0.097). CONCLUSION: This study demonstrated that changing the SRI influences the spatial replication accuracy of 3D-printed models constructed by FDM. Matching the SRI to the primary spatial resolution limiting factor of acquisition slice width or printer capabilities optimises replication accuracy.

Reject rate analysis in digital radiography: an Australian emergency imaging department case study.

INTRODUCTION: Reject analysis in digital radiography (DR) helps guide the education and training of staff, influences department workflow, reduces patient dose and improves department efficiency. The purpose of this study was to investigate rejected radiographs at a major metropolitan emergency imaging department to help form a benchmark of reject rates for DR and to assess what radiographs are being rejected and why. METHODS: A retrospective longitudinal study was undertaken as an in-depth clinical audit. The data were collected using automated reject analysis software from two digital x-ray systems from June 2015 to April 2017. The overall reject rate, reasons for rejection as well as the reject rates for individual radiographers, examination types and projections were analysed. RESULTS: A total of 90,298 radiographic images were acquired and included in the analysis. The average reject rate was 9%, and the most frequent reasons for image rejection were positioning error (49%) and anatomy cut-off (21%). The reject rate varied between radiographers as well as for individual examination types and projections. CONCLUSIONS: The variation in radiographer reject rates and the high reject rate for some projections indicate that reject analysis is still necessary as a quality assurance tool for DR. A feedback system between radiologists and radiographers may reduce the high percentage of positioning errors by standardising the technical factors used to assess image quality. Future reject analysis should be conducted regularly incorporating an exposure indicator analysis as well as retrospective assessment of individual rejected images.

Bi-plane and single plane angiography: a study to compare contrast usage and radiation doses for adult cardiac patients in diagnostic studies.

OBJECTIVE:: This study compares the performance of bi-plane coronary angiography against single plane angiography in terms of the volume of contrast used (ml) and the total dose-area product (DAP) (µGym2) to the patient measured directly via flat panel detectors. METHODS:: A total of 5176 adult diagnostic cardiac angiograms from a hospital in Brisbane, Australia were retrospectively studied. Patients with aortograms, iliac or femoral artery imaging, and stenting or graft interventions were excluded. Student's t-tests were used to compare means, and confounding variables were compared using multivariate regression. This quantified the effects of bi-plane system use holding constant other factors (e.g.) body mass index (BMI), age, room, sex, number of digital acquisitions and fluoro time. RESULTS:: Bi-plane imaging had an average difference in mean contrast use of -15.1 ml [15.5% 95% confidence interval (CI) (-13.2, -17.0) p<0.001], multivariate regression demonstrated a -27.0 ml reduction in contrast use [28% 95% CI (-29.0, -24.83) p<0.0001] when the significant effects of fluoro time, number of digital acquisitions, BMI and sex were held constant. Bi-plane imaging had an average difference in mean DAP of + 887.1 µGym2 [23% 95% CI (+1110.7, +663.4) p < 0.001], whilst multivariate regression found a +628.3 Gym2 increase in DAP [16% 95% CI (+467.5, +789.3) p<0.001] when the significant effects of fluoro time, number of digital acquisitions, BMI and sex were held constant. CONCLUSION:: These results demonstrate that bi-plane imaging uses less contrast media than single-plane imaging for coronary angiography at the expense of more radiation. Bi-plane imaging may be preferable in patients with renal impairment, however single plane imaging may be preferable in those without renal impairment. ADVANCES IN KNOWLEDGE:: This is a large cohort and statistically comprehensive study comparing bi-plane and single plane coronary angiography. Other studies 4, 5, 6, 12 have used Student's t-tests to measure the difference between means, however this provides no causative information on the differences found. This study provides a view of the causative impact of bi-plane usage on DAP and contrast use via multivariate regression modelling.