A Possible Case of Neurogenic Pulmonary Edema in a Sheep following Intracranial Surgery

A 3-year-old female crossbred sheep weighing 64 kg was anaesthetized for intracranial surgery as a part of a research project. Premedication and induction of anesthesia were uneventful as well as tracheal intubation. Anesthesia was maintained with isoflurane in a 50% mixture of oxygen and air, fentanyl (5-15 µg kg-1h-1) and lidocaine (1.8 mg kg-1h-1). During anesthesia, an increased alveolar-arterial oxygen gradient was calculated on the basis of arterial blood gas analysis: inspiratory fraction of oxygen was increased and a recruitment manoeuvre was performed. After 210 minutes of anesthesia, the sheep was let recover with oxygen supplementation under monitoring of pulse-oxymetry, capnography, inspired and expired oxygen, temperature and invasive blood pressure. At tracheal extubation no signs of regurgitation or aspiration were noticed. Twenty-five minutes later, the sheep showed deterioration of neurological status and clonic seizure responsive to diazepam. After transient tachycardia, blood pressure rose acutely and sinus bradycardia followed. Severe tachypnea started in few minutes accompanied by loud respiratory noises and harsh diffuse crackles on both sides of the thorax. Foamy blood nasal exudates discharged from the nostrils. Neurogenic pulmonary edema as a sequel of increased intracranial pressure was suspected and treated with intravenous mannitol (0.5 gkg-1) and furosemide (4 mgKg-1). Hypoxemia was successfully managed with oxygen supplementation. Motor and cognitive functions improved progressively and were deemed normal within 12 hours from the episode, when arterial partial pressure of oxygen was 11.7 kPa (88 mmHg) at room air

Benthic pH gradients across a range of shelf sea sediment types linked to sediment characteristics and seasonal variability

This study used microelectrodes to record pH profiles in fresh shelf sea sediment cores collected across a range of different sediment types within the Celtic Sea. Spatial and temporal variability was captured during repeated measurements in 2014 and 2015. Concurrently recorded oxygen microelectrode profiles and other sedimentary parameters provide a detailed context for interpretation of the pH data. Clear differences in profiles were observed between sediment type, location and season. Notably, very steep pH gradients exist within the surface sediments (10–20 mm), where decreases greater than 0.5 pH units were observed. Steep gradients were particularly apparent in fine cohesive sediments, less so in permeable sandier matrices. We hypothesise that the gradients are likely caused by aerobic organic matter respiration close to the sediment–water interface or oxidation of reduced species at the base of the oxic zone (NH4+, Mn2+, Fe2+, S−). Statistical analysis suggests the variability in the depth of the pH minima is controlled spatially by the oxygen penetration depth, and seasonally by the input and remineralisation of deposited organic phytodetritus. Below the pH minima the observed pH remained consistently low to maximum electrode penetration (ca. 60 mm), indicating an absence of sub-oxic processes generating H+ or balanced removal processes within this layer. Thus, a climatology of sediment surface porewater pH is provided against which to examine biogeochemical processes. This enhances our understanding of benthic pH processes, particularly in the context of human impacts, seabed integrity, and future climate changes, providing vital information for modelling benthic response under future climate scenarios

Automatic 3D camera positioning in cardiac computed tomography:A phantom study

Introduction: Cardiac computed tomography angiography (CCTA) is essential for diagnosing coronary artery disease, with accurate positioning critical for optimising image quality (IQ) and radiation exposure. Vertical misalignment can degrade IQ and increase radiation dose. Automatic 3D camera positioning systems claim to improve accuracy and reduce errors, though research on their effectiveness in CCTA remains limited. This study evaluates positioning accuracy, radiation dose, and IQ when using automatic 3D camera positioning in CCTA across scenarios. Methods: This prospective phantom study utilised the Multipurpose Chest N1 Phantom (Kyoto Kagaku, Japan) across three body sizes. Positioning variations included supine versus prone, head-first versus feet-first orientations, and various body surface coverings. CT scans were undertaken on a GE Revolution Apex Elite (GE Healthcare, USA) scanner. Vertical offsets from the isocentre were measured using DoseWatch software (GE Healthcare), while radiation dose was quantified through dose-length product (DLP) and Computed Tomography Dose Index (CTDIvol). IQ was assessed by calculating the signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and conspicuity index. Results: Automatic 3D camera positioning achieved a mean (standard deviation) vertical offset of −1.0 (1.5) mm. Larger phantom sizes were significantly associated with increased off-centring, as indicated by Fisher's exact test (p = 0.004), and greater offsets correlated with higher radiation doses (r = 0.45, p &lt; 0.05). IQ metrics, including SNR and CNR, decreased with increased offsets; SNR dropped from 71. to 50.9, and CNR from 0.2 to −0.6. Conclusion: This study demonstrates that automated 3D camera positioning in CCTA supports radiographers by enhancing positioning accuracy, lowering radiation exposure and improving IQ. Further work should examine the impact of automatic 3D camera positioning within clinical practice. Implication for practice: Automatic 3D camera positioning in CCTA will likely improve patient care and safety.</p

Exploring radiographers' experience with mobile X-ray of patients in their homes

Introduction: To offer citizens with frailty or dementia living in nursing homes or other institutions a less stressful and anxious X-ray examination, a Danish hospital offers to perform the examination in the citizen's residence. This has changed the working procedure for the radiographers performing the examination. The aim of this study was to explore if the radiographers self-perceived competencies have changed whilst working in the mobile X-ray unit and if so, how these competencies are utilised within the department-based medical imaging team. Method: This study had a qualitative design following a hermeneutic approach. Individual semi structured interviews included nine radiographers, four radiographers working in the mobile X-ray unit and five radiographers working exclusively in the medical imaging team. Results: Radiographers who worked in the mobile X-ray unit did acquire new competencies such as better communication and creative positioning skills. All nine participants recognised the advantage of sharing experiences and competencies with colleagues, and recommended a formal forum to do so. They sought opportunities for the use of the mobile X-ray unit to be more widespread within their own region, and within the profession. Conclusion: This study indicates that radiographers working with mobile X-ray unit gained new competencies in communication and positioning, but without spread of new knowledge to colleagues in the medical imaging team. Implication for practice: The use of home-based mobile X-ray is a new way to provide health care services and gain new competencies for the radiographers to focus on patient centred care.</p

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 &lt; 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 &lt; 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 &lt; 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.</p

Determination of cutoff values on computed tomography and magnetic resonance images for the diagnosis of atlantoaxial instability in small-breed dogs.

OBJECTIVE To determine cutoff values for the diagnosis of atlantoaxial instability (AAI) based on cross-sectional imaging in small-breed dogs. STUDY DESIGN Retrospective multicenter study. SAMPLE POPULATION Client-owned dogs (n = 123) and 28 cadavers. METHODS Dogs were assigned to three groups: a control group, a "potentially unstable" group, and an AAI-affected group, according to imaging findings and clinical signs. The ventral compression index (VCI), cranial translation ratio (CTR), C1-C2 overlap, C1-C2 angle, atlantoaxial distance, basion-dens interval, dens-to-axis length ratio (DALR), power ratio, and clivus canal angles were measured on CT or T2-weighted magnetic resonance (MR) images. Receiver operating characteristic (ROC) analysis was performed to define cutoff values in flexed (≥25°) and extended (<25°) head positions. RESULTS Cutoff values for the VCI of ≥0.16 in extended and ≥0.2 in flexed head positions were diagnostic for AAI (sensitivity of 100% and 100%, specificity of 94.54% and 96.67%, respectively). Cutoff values for the other measurements were defined with a lower sensitivity (75%-96%) and specificity (70%-97%). A combination of the measurements did not increase the sensitivity and specificity compared with the VCI as single measurement. CONCLUSION Cutoff values for several imaging measurements were established with good sensitivity and specificity. The VCI, defined as the ratio between the ventral and dorsal atlantodental interval, had the highest sensitivity and specificity in both head positions. CLINICAL SIGNIFICANCE The use of defined cutoff values allows an objective diagnosis of AAI in small-breed dogs. The decision for surgical intervention, however, should remain based on a combination of clinical and imaging findings

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.</p

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 &lt; 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 &lt; 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.</p

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