The use of near infrared spectroscopy (NIRS) to measure vascular haemodynamics in human bone tissue in vivo

Rationale: Poor cardiovascular health is associated with reduced bone strength and increased risk of fragility fracture. However, direct measurement of intraosseous vascular health is difficult due to the density and mineral content of bone. The aim of this PhD project was to investigate the feasibility of near infrared spectroscopy (NIRS) for the investigation of vascular haemodynamics in human bone in vivo. NIRS provides inexpensive, non-invasive, safe, and real time data on changes in oxygenated and deoxygenated haemoglobin concentration at superficial anatomical sites. NIRS utilises a source optode of near infrared (NIR) light and detector optode that obtains representative data of the interactions of NIR photons with tissue. Method: A systematic review was performed identifying the current existing applications of NIRS (and similar technologies) for measuring human bone tissue in vivo. This review informed the development of an arterial occlusion protocol for obtaining haemodynamic measurements of the proximal tibia and lateral calf, including assessment of the protocol’s reliability. For thirty-six participants, NIRS results were also compared to alternative tests of bone haemodynamics involving dynamic contrast enhanced MRI (DCE-MRI), and measures of general bone health based on dual x-ray absorptiometry testing and blood markers of bone metabolism. Results: This thesis presents novel data demonstrating NIRS can obtain acceptably reliable markers of haemodynamics at the proximal tibia in vivo, comparable with reliability assessments of alternative modalities measuring intraosseous haemodynamics, and the use of NIRS for measuring muscle. Novel associations have been demonstrated between haemodynamic markers measured with NIRS and DCE-MRI, giving confidence NIRS truly represents bone haemodynamics. Increased NIRS markers of oxygen extraction during occlusion, and greater post-ischaemic vascular response to occlusion, were both associated with greater bone mineral density. Conclusion: As a feasibility study, this PhD project has demonstrated the potential for NIRS to contribute to research around the potential pathophysiological role of vascular dysfunction within bone tissue, but also the limitations and need for further development of NIRS technology.The Royal College of Radiologist

Imaging in Osteoporosis

This is the author accepted manuscript. The final version is available from Pavilion Publishing via the link in this record.Osteoporosis is a prevalent metabolic bone disease in the western world, resulting in low trauma fractures and increased morbidity and mortality rates among sufferers. The article describes the common imaging required in the diagnosis and management of osteoporosis. It is important to include imaging within the patient pathway where vertebral fractures are suspected and to use additional imaging modalities such as MRI to aid differential diagnosis where the cause of the fracture is unclear. Radiographers and radiologists reporting imaging examinations may be the first clinicians to suspect the presence of osteoporosis and have a role in helping to ensure that these patients do not get missed so that appropriate treatment can be started. Ideally there should be locally-agreed pathways whereby such patients are automatically referred to the fracture liaison service, regardless of the original requester of the imaging investigation

Computer-aided detection in musculoskeletal projection radiography: A systematic review

This is the author accepted manuscript. The final version is available from WB Saunders via the DOI in this record.Objectives To investigated the accuracy of computer-aided detection (CAD) software in musculoskeletal projection radiography via a systematic review. Key findings Following selection screening, eligible studies were assessed for bias, and had their study characteristics extracted resulting in 22 studies being included. Of these 22 three studies had tested their CAD software in a clinical setting; the first study investigated vertebral fractures, reporting a sensitivity score of 69.3% with CAD, compared to 59.8% sensitivity without CAD. The second study tested dental caries diagnosis producing a sensitivity score of 68.8% and specificity of 94.1% with CAD, compared to sensitivity of 39.3% and specificity of 96.7% without CAD. The third indicated osteoporotic cases based on CAD, resulting in 100% sensitivity and 81.3% specificity. Conclusion The current evidence reported shows a lack of development into the clinical testing phase; however the research does show future promise in the variation of different CAD systems

Optimizing projectional radiographic imaging of the abdomen of obese patients: an e-Delphi study

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.Purpose: Obesity is increasing in prevalence globally, with increased demands placed on radiology departments to image obese patients to assist with diagnosis and management. The aim of this study was to determine perceived best practice techniques currently used in clinical practice for projectional radiography of the abdomen for obese patients with the aim to help elucidate areas for future research and education needs in this field. Experimental Design: A two round e-Delphi study was undertaken to establish a consensus within a reference group of expert Australian clinical educator diagnostic radiographers (CEDRs). Initially, a conceptual map of issues regarding imaging obese patients was undertaken by analysing interview transcripts of 12 CEDRs. This informed an online questionnaire design used in Delphi rounds 1 and 2. A consensus threshold was set <75% “agreement/disagreement”, with 15 and 14 CEDRs participating in rounds 1 and 2, respectively. Results: Seven of the 11 statements reach consensus after round 2. Consensus on using a combination of higher peak kilovoltage (kVp) and milliampere-seconds (mAs) to increase radiation exposure increased source-to-image distance and tighter collimation was achieved. There was no consensus regarding patient positioning practices or patient communication strategies. The expert group reported the importance of personal confidence and treating patients as individuals when applying techniques. Conclusion: Diversity of experts' opinions and current practice may be due to the variations in obese patients’ size and presentation. Therefore, there is a need for extensive empirical evidence to underpin practice and education resources for radiographers when imaging obese patients

Coinductive interpreters for process calculi

This paper suggests functional programming languages with coinductive types as suitable devices for prototyping process calculi. The proposed approach is independent of any particular process calculus and makes explicit the different ingredients present in the design of any such calculi. In particular structural aspects of the underlying behaviour model (e.g. the dichotomies such as active vs reactive, deterministic vs nondeterministic) become clearly separated from the interaction structure which defines the synchronisation discipline. The approach is illustrated by the detailed development in Charity of an interpreter for a family of process languages.(undefined

Understanding patient views and acceptability of predictive software in osteoporosis identification

This is the final version. Available from Elsevier via the DOI in this record. Introduction: Research into patient and public views on predictive software and its use in healthcare is relatively new. This study aimed to understand older adults' acceptability of an opportunistic bone density assessment for osteoporosis diagnosis (IBEX BH), views on its integration into healthcare, and views on predictive software and AI in healthcare. Methods: Focus groups were conducted with participants aged over 50 years, based in South West England. Data were analysed using thematic analysis. Analysis was informed by the theoretical framework of acceptability. Results: Two focus groups were undertaken with a total of 14 participants. Overall, the participants were generally positive about the IBEX BH software, and predictive software's in general stating ‘it sounds like a brilliant idea’. Although participants did not understand the intricacies of the software, they did not feel they needed to. Concerns about IBEX BH focussed more on the clinical indications of the software (e.g. more scans or medications), with participants expressing less trust in results if they indicated medication. Questions were also raised about how and who would receive the results of this software. Individual choice was evident in these discussions, however most indicated the preferences for spoken communication ‘But I would expect that these results would be given by a human to another human.’ Conclusions: Focus group participants were generally accepting of the use of predictive software in healthcare. Implications for practice: Thought and care needs to be taken when integrating predictive software into practice. Focusses on empowering patients, providing information on processes and results are keyTranslational Research Exchange @ Exeter (TREE

The development and evaluation of an audit tool for measuring reporting accuracy of radiographers compared with radiologists for intra-luminal pathology detected at computed tomography colonography (CTC)

This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.Objective: To design and test an audit tool to measure the reporting accuracy of radiographers using radiologist reports as the gold standard. Design: A database was designed to capture radiographer and radiologist report data. The radiographer preliminary evaluation of intraluminal pathology was given a score (PDS score) by the reporting radiologist based on the pathology present, the discrepancy between the preliminary evaluation and the final report and the significance of that discrepancy on the clinical management of the patient. To test the reliability of this scoring system, 30 randomly selected cases (n=1815) were retrospectively compared and assessed for accuracy using the PDS score by 3 independent practitioners. Inter rater reliability was assessed using percentage agreement and kappa scores. Results: There was 100% agreement between participants for all significant pathologies. Inter rater agreement was 80-93% for normal studies and insignificant pathologies. Conclusion: Results indicate that the tool provides a practical, easy to use and reliable method to record, monitor and evaluate a preliminary evaluation of the colon by radiographers

A systematic review of repeatability and reproducibility studies of diffusion tensor imaging of cervical spinal cord

This is the final version. Available on open access from the British Institute of Radiology via the DOI in this recordObjectives: Diffusion tensor imaging (DTI) techniques are being studied as a possible diagnostic and predictive tool for the evaluation of cervical spinal cord disease. This systematic review aims to evaluate the previous DTI studies that specifically investigated the repeatability and reproducibility of DTI in the cervical spinal cord. Methods and materials: A search in the PubMed, Scopus, Web of Science and Ovid electronic databases was conducted for articles published between January 1990 and February 2022 that related to the repeatability and reproducibility of DTI in evaluating the cervical spinal cord using one of the following measurements: the intraclass correlation coefficient (ICC) and/or the coefficient of variation (CV), and/or Bland-Altman (BA) differences analysis methods. DTI studies that presented full statistical analysis of repeatability and/or reproducibility tests of the cervical spinal cord in peer-reviewed full-text publications published in journals were included. Articles that included at least one of the keywords within the titles or abstracts were identified. Additional full-text papers were found by searching the citations and reference lists of related articles. This review has followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidance. Risk of bias was evaluated with 13 criteria weighted toward methodological quality of reported studies using the QuADS assessment criteria. This assessment only included full-text articles written in English. Results: A total of 11 studies were included and assessed for different characteristics, including sample size,(3–34) re-test time interval (3 months), test-retest reproducibility scores and acquisition method. Six studies used ICC which ranged from poor (ICC<0.37) to excellent reproducibility (ICC 0.91–0.99). Four studies reported an overall CV lower than 40% for all DTI metrics. Three studies reported the Bland-Altman (BA) differences and reported a minimum percentage showing no strong differences between repeated measurements. Quantitative analysis was not undertaken due to heterogeneity of methods. Repeatability and reproducibility measures were generally found to be good. Conclusion: This study revealed that the application of DTI and its related measures in a clinical setting in the assessment of cervical spinal cord changes is feasible and reproducible. However, cervical spinal cord DTI suffers from some existing limitations that prevent it from being routinely used in research and clinical settings.Najran University, Kingdom of Saudi Arabi