Influence of an Early Human Milk Diet on the Duration of Parenteral Nutrition and Incidence of Late-Onset Sepsis in Very Low Birthweight (VLBW) Infants: A Systematic Review.

Introduction: Human milk is the preferred source of enteral nutrition for very low birthweight (VLBW) infants, and it possibly decreases dependence on parenteral nutrition (PN) and reduces incidence of late-onset sepsis (LOS). No systematic review to date has specifically addressed the value of early versus late introduction of human milk diet (HMD) on duration of PN and incidence of LOS among VLBW infants. Objective: To review the evidence for an early versus late introduction of HMD on duration of PN and incidence of LOS in VLBW infants. Method: Preferred reporting items for systematic reviews and meta-analysis-guided search of EMBASE and PubMed/Medline databases was conducted for this systematic review using phrases addressing population, intervention, comparator, and outcome framework to identify articles published over the past two decades without language restrictions. Full-text articles (both observational and randomized) that studied an early versus late initiation of HMD were included. Mean difference (MD) and relative risk (RR) with 95% confidence intervals (CIs) were calculated for PN and LOS. Quality of evidence was analyzed using UK National Service Framework and the risk-of-bias was assessed using Robvis®. Results: One randomized controlled trial (RCT) and two observational studies (two English and one Chinese) recruited 474 VLBW infants (455 analyzed). Among an intrauterine growth-restricted cohort enrolled in the RCT (n = 72), early HMD resulted in statistically significant reduction in PN dependence. However, no statistically significant difference was found in LOS. Two observational studies found similar reductions in PN duration and LOS incidence among the early HMD cohort. One observational study reported significant PN reduction; however, the incidence of LOS did not reach statistical significance in either case. Conclusion: An early HMD may reduce the duration of PN for a growth-restricted VLBW cohort. Observational studies suggesting reduced PN and LOS from early HMD endorse the need for bioactivity-focused human milk research. Variations in feeding guidelines among VLBW infants have the potential to influence neonatal outcomes significantly.

Design and initial testing of a novel disposable oscillating positive expiratory pressure device.

BACKGROUND: Oscillating positive expiratory pressure (OPEP) devices play a key role in airway clearance, particularly in patients with cystic fibrosis. These devices, however, have the potential to become reservoirs for pathogenic organisms and require daily, or even more frequent, cleaning. This places a large burden on patients and their carers. AIMS: The objective of this work was to develop a disposable OPEP device, with comparable mechanical performance to commercial devices, that negates the need for cleaning after use thus reducing microbiological risks. METHODS: 3D printing was used to iterate and develop a prototype disposable device (The University of Limerick OPEP, abbreviated to the UL-OPEP) that was compared with a selection of commercially available devices for mean pressure and oscillation amplitude (cmH2O), as well as oscillation frequency (Hz). All devices were tested using a healthy volunteer at a target expiratory flow of ~ 20 L/min. The target therapeutic range was 10-20 cmH2O at a flow rate of 10-20 L/min as is reported widely in the literature. RESULTS: The prototype disposable device achieved a mean pressure of 14.82 cmH2O at a mean flow rate of 18.82 L/min, and generated an oscillation frequency of 26 Hz with an amplitude of 1.28 cmH2O. These characteristics compare favourably with existing, more complex, reusable OPEP devices. CONCLUSIONS: The UL-OPEP device is a small, disposable OPEP device, that generates pressure and oscillation amplitudes for clinically effective airway clearance. The device negates the need for cleaning and disinfecting, removing the risk of devices acting as a potential reservoir for pathogenic organisms while maintaining mucus-clearing benefits.

Ensemble Kalman inversion for magnetic resonance elastography.

Magnetic resonance elastography (MRE) is an MRI-based diagnostic method for measuring mechanical properties of biological tissues. MRE measurements are processed by an inversion algorithm to produce a map of the biomechanical properties. In this paper a new and powerful method (ensemble Kalman inversion with level sets (EKI)) of MRE inversion is proposed and tested. The method has critical advantages: material property variation at disease boundaries can be accurately identified, and uncertainty of the reconstructed material properties can be evaluated by consequence of the probabilistic nature of the method. EKI is tested in 2D and 3D experiments with synthetic MRE data of the human kidney. It is demonstrated that the proposed inversion method is accurate and fast.

Exercise Interventions for Women with Ovarian Cancer: A Realist Review.

BACKGROUND: Despite evidence indicating the benefits of exercise interventions for women with ovarian cancer both during and following treatment, uptake is poor. There is limited research exploring the implementation of such interventions for this cohort of women. The purpose of this review was to identify implementation theories in relation to exercise interventions for women with stages I-IV ovarian cancer, both during and following treatment; to explain positive and negative contextual factors, which may help or hinder implementation; and to develop a theory on how exercise interventions for women with ovarian cancer may be implemented. METHODS: This realist review sourced literature from five electronic databases: CINAHL plus, Medline, Embase, PsycINFO and Google Scholar. Methodological rigour was assessed using the relevant critical appraisal skills programme tools. RESULTS: Nine papers were included. Two intervention stages were identified: first, optimising uptake by providing education to patients on the benefits of exercise, approaching patients when symptoms are adequately managed and offering a personalised exercise programme; second, adherence and retention are influenced by the provision of an "autoregulated" exercise programme with additional supportive infrastructure, individualised goal setting and symptom management support where required. CONCLUSION: Women with ovarian cancer are reluctant to engage in exercise interventions, despite the supporting evidence in terms of positive clinical outcomes. This realist review elucidates underlying mechanisms and important contextual factors that will support and guide the implementation of exercise interventions for this cohort of women.

Lessons learned from a pandemic: implications for a combined exercise and educational programme for medical students.

BACKGROUND: The 'MED-WELL' programme is a combined exercise and educational intervention designed to promote well-being among medical students and educate students about prescribing exercise as medicine in clinical practice. Due to COVID-19 public health restrictions of social distancing the 'MED-WELL' programme was offered online instead of in-person in 2021. The aim of this study is to compare the experiences of participants in the 'MED-WELL' programme online to those that previously participated in the same programme in-person to understand the student experience and optimize programme delivery. METHODS: Purposive sampling was used to recruit 20 participants to a qualitative study using semi-structured interviews. Ten study participants took part in the 'MED-WELL' programme when it was offered in-person, and the other ten study participants took part in the programme when it was offered online. All interviews were audio-recorded and transcribed using Microsoft Teams. A combined inductive and deductive approach was used for analysis. An inductive thematic analysis was utilized to categorize data into higher order codes, themes, and overarching themes. The theory of online learning provided the theoretical framework for a deductive approach. RESULTS: Analysis of the data produced five overarching themes: 'student-student', 'student-teacher', 'student-content', 'student-environment', and 'effects of a pandemic'. The first four themes detail distinct types of interaction that participants had with various entities of the 'MED-WELL' programme and the effects that these interactions had on participant experiences. 'Effects of a pandemic' refers to the context of delivering the 'MED-WELL' programme online during a pandemic and how this mode of delivery influenced participants and the programme. CONCLUSIONS: Optimizing the 'MED-WELL' programme relies on an understanding of how participants interact with different entities of the programme and are motivated to attend and engage. Participants tended to favour an in-person mode of delivery, however certain advantages of delivering the programme online were also identified. The findings from this study can be used to inform similar experiential and educational exercise interventions, and may help plan for potential future restrictions on in-person educational and exercise-based programmes.

OSCE rater cognition - an international multi-centre qualitative study.

INTRODUCTION: This study aimed to explore the decision-making processes of raters during objective structured clinical examinations (OSCEs), in particular to explore the tacit assumptions and beliefs of raters as well as rater idiosyncrasies. METHODS: Thinking aloud protocol interviews were used to gather data on the thoughts of examiners during their decision-making, while watching trigger OSCE videos and rating candidates. A purposeful recruiting strategy was taken, with a view to interviewing both examiners with many years of experience (greater than six years) and those with less experience examining at final medical examination level. RESULTS: Thirty-one interviews were conducted in three centres in three different countries. Three themes were identified during data analysis, entitled 'OSCEs are inauthentic', 'looking for glimpses of truth' and 'evolution with experience'. CONCLUSION: Raters perceive that the shortcomings of OSCEs can have unwanted effects on student behaviour. Some examiners, more likely the more experienced group, may deviate from an organisations directions due to perceived shortcomings of the assessment. No method of assessment is without flaw, and it is important to be aware of the limitations and shortcomings of assessment methods on student performance and examiner perception. Further study of assessor and student perception of OSCE performance would be helpful.

In silicoevaluation and optimisation of magnetic resonance elastography of the liver.

Objective.Magnetic resonance elastography (MRE) is widely adopted as a biomarker of liver fibrosis. However,in vivoMRE accuracy is difficult to assess.Approach.Finite element model (FEM) simulation was employed to evaluate liver MRE accuracy and inform methodological optimisation. MRE data was simulated in a 3D FEM of the human torso including the liver, and compared with spin-echo echo-planar imaging MRE acquisitions. The simulated MRE results were compared with the ground truth magnitude of the complex shear modulus (∣G*∣) for varying: (1) ground truth liver ∣G*∣; (2) simulated imaging resolution; (3) added noise; (4) data smoothing. Motion and strain-based signal-to-noise (SNR) metrics were evaluated on the simulated data as a means to select higher-quality voxels for preparation of acquired MRE summary statistics of ∣G*∣.Main results.The simulated MRE accuracy for a given ground truth ∣G*∣ was found to be a function of imaging resolution, motion-SNR and smoothing. At typical imaging resolutions, it was found that due to under-sampling of the MRE wave-field, combined with motion-related noise, the reconstructed simulated ∣G*∣ could contain errors on the scale of the difference between liver fibrosis stages, e.g. 54% error for ground truth ∣G*∣ = 1 kPa. Optimum imaging resolutions were identified for given ground truth ∣G*∣ and motion-SNR levels.Significance.This study provides important knowledge on the accuracy and optimisation of liver MRE. For example, for motion-SNR ≤ 5, to distinguish between liver ∣G*∣ of 2 and 3 kPa (i.e. early-stage liver fibrosis) it was predicted that the optimum isotropic voxel size is 4-6 mm.

An initial evaluation of the safety of a disposable oscillating positive expiratory pressure device in patients with chronic obstructive pulmonary disease: a sort-term pilot study.

BACKGROUND: Handheld oscillating positive expiratory pressure (OPEP) devices have been a mainstay of treatment for patients with hypersecretory conditions such as cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD) since the 1970s. Current devices are reusable and require regular cleaning and disinfection to prevent harbouring potentially pathogenic organisms. Adherence to cleaning regimens for respiratory devices is often poor and in response to this, a prototype disposable OPEP device-the 'UL-OPEP' (University of Limerick-Oscillating Positive Expiratory Pressure device)-was developed to mitigate the risk of contamination by pathogens. The device was previously evaluated successfully in a group of paediatric CF patients. The aim of the current study was to initially evaluate the safety of the prototype in patients with COPD over a period of 1 month to ensure no adverse events, negative impacts on lung function, exercise tolerance, or quality of life. Data on user experience of the device were also collected during post-study follow-up. METHODS: A sample of 50 volunteer participants were recruited from pulmonary rehabilitation clinics within the local hospital network. The patients were clinically stable, productive, and not current or previous users of OPEP devices. Participants were invited to use a prototype disposable OPEP device daily for a period of 1 month. Pre- and post-study lung function was assessed with standard spirometry, and exercise tolerance with the 6-min-walk-test (6MWT). Quality of life was assessed using the St. George's Respiratory Questionnaire (SGRQ), and user experience of the prototype device evaluated using a post-study questionnaire. RESULTS: 24 Participants completed the study: 9 were female. Overall median age was 67.5 years, range 53-85 years. Lung function, 6-min walk test, and SGRQ scores showed no significant change post-study. User feedback was positive overall. CONCLUSIONS: The results indicate that the UL-OPEP is safe to use in patients with COPD. No adverse events were recorded during the study or in the follow-up period of 2 weeks. The device did not negatively impact patients' lung function, exercise tolerance, or quality of life during short term use (1 month), and usability feedback received was generally positive. Larger, longer duration studies will be required to evaluate efficacy. Registration The study was approved as a Clinical Investigation by the Irish Health Products Regulatory Authority (CRN-2209025-CI0085).

A short-term evaluation of a prototype disposable Oscillating Positive Expiratory Pressure (OPEP) device in a cohort of children with cystic fibrosis.

BACKGROUND: Oscillating Positive Expiratory Pressure (OPEP) devices are important adjuncts to airway clearance therapy in patients with cystic fibrosis (CF). Current devices are typically reusable and require daily, or often more frequent, cleaning to prevent risk of infection by acting as reservoirs of potentially pathogenic organisms. In response, a daily disposable OPEP device, the UL-OPEP, was developed to mitigate the risk of contamination and eliminate the burdensome need for cleaning devices. METHODS: A convenience sample of 36 participants, all current OPEP device users, was recruited from a paediatric CF service. For one month, participants replaced their current OPEP device with a novel daily disposable device. Assessment included pre- and post-intervention lung function by spirometry, as well as Lung Clearance Index. Quality of life was assessed using the Cystic Fibrosis Questionnaire - Revised, while user experience was evaluated with a post-study survey. RESULTS: 31 participants completed the study: 18 males; median age 10 years, range 4-16 years. Lung function (mean difference ± SD, %FEV1 = 1.69 ± 11.93; %FVC = 0.58 ± 10.04; FEV1: FVC = 0.01 ± 0.09), LCI (mean difference ± SD, 0.08 ± 1.13), six-minute walk test, and CFQ-R were unchanged post-intervention. Participant-reported experiences of the device were predominantly positive. CONCLUSIONS: The disposable OPEP device maintained patients' lung function during short term use (≤ 1 month), and was the subject of positive feedback regarding functionality while reducing the risk of airway contamination associated with ineffective cleaning. REGISTRATION: The study was approved as a Clinical Investigation by the Irish Health Products Regulatory Authority (CRN-2209025-CI0085).

Unprecedented reduction in births of very low birthweight (VLBW) and extremely low birthweight (ELBW) infants during the COVID-19 lockdown in Ireland: a 'natural experiment' allowing analysis of data from the prior two decades.

BACKGROUND: Aetiology of births involving very low birthweight (VLBW) and extremely low birthweight (ELBW) infants is heterogeneous and preventive strategies remain elusive. Socioenvironmental measures implemented as Ireland's response to the SARS-CoV-2 virus (COVID-19) pandemic represented a national lockdown, and have possibly influenced the health and well-being of pregnant women and unborn infants. METHODS: Regional trends of VLBW and ELBW infants in one designated health area of Ireland over two decades were analysed. Poisson regression and rate ratio analyses with 95% CI were conducted. Regional data covering most of the lockdown period of 2020 were compared with historical regional and national data and forecasted national figures for 2020. RESULTS: Poisson regression analysis found that the regional historical VLBW rate per 1000 live births for January to April, 2001-2019 was 8.18 (95% CI 7.21 to 9.29). During January to April 2020, an unusually low VLBW rate of just 2.17 per 1000 live births was observed, reflecting a rate ratio of 3.77 (95% CI 1.21 to 11.75), p=0.022, representing a 73% reduction of VLBW during the first 4 months of 2020 compared with same period for the preceding two decades. There were no ELBW infants admitted to the regional neonatal intensive care unit. National Irish VLBW rate for 2020 is forecasted to be reduced to approximate 400 per 60 000 births compared with the historical 500-600 range. CONCLUSION: An unprecedented reduction in regional births of VLBW and ELBW infants was observed in Ireland coinciding with the COVID-19 lockdown. Potential determinants of this unique temporal trend possibly reside in the summative socioenvironmental impact of the COVID-19 lockdown. Our findings, if mirrored in other regions that have adopted a lockdown, demonstrate the potential to evaluate these implicated behavioural and socioenvironmental modifiers to positively influence VLBW and ELBW rates globally.

Oscillating Positive Expiratory Pressure Therapy May Be Performed Poorly by Children With Cystic Fibrosis.

BACKGROUND: Oscillating positive expiratory pressure devices aid removal of excess secretions and reduce gas trapping in patients with hypersecretory pulmonary diseases, for example, cystic fibrosis. Oscillating positive expiratory pressure works when the patient exhales actively against a fixed resistor, which generates mean intrapulmonary pressures of 10-20 cm H2O with rapid fluctuations of at least 1 cm H2O from the mean. In this study, we evaluated the performance of oscillating positive expiratory pressure therapy by pediatric subjects with cystic fibrosis to determine adherence to target therapeutic pressures. METHODS: Twenty-one pediatric subjects were recruited. Each had a history of using an oscillating positive expiratory pressure device twice daily and had received standardized training and instructions from the same specialist physiotherapist. Performance was evaluated by using a flow and pressure sensor placed in-line between the participant's mouth and the device. The participants performed expirations as per their normal routine. RESULTS: None of the participants achieved target therapeutic pressure ranges during expiration. The mean ± SD pressure generated was 16.2 ± 6.8 cm H2O, whereas mean ± SD flow was 31.3 ± 8.9 L/min. The mean ± SD expiration length was 2.5 ± 1.4 s. CONCLUSIONS: Despite standardized instruction, the results demonstrated considerable variation among the participants and overall poor technique during use. Outcomes of this study indicated that airway clearance effects of oscillating positive expiratory pressure were compromised due to poor technique.

Internet skills of medical faculty and students: is there a difference?

BACKGROUND: The shift from a more didactic to student-centred pedagogical approach has led to the implementation of new information communication technology (ICT) innovations and curricula. Consequently, analysis of the digital competency of both faculty and students is of increasing importance. The aim of this research is to measure and compare the internet skills of medical school faculty and students and to investigate any potential skills gap between the two groups. METHODS: A survey of medical school faculty and students across three universities in Ireland was carried out using a validated instrument (Internet Skills Scale) measuring five internet skills (Operational, Information Navigation, Social, Creative and Mobile). Three focus groups comprising a total of fifteen students and four semi-structured interviews with faculty across three institutions were carried out to explore further findings and perceptions towards digital literacy, give further insight and add context to the findings. RESULTS: Seventy-eight medical faculty (response rate 45%) and 401 students (response rate 15%) responded to the survey. Mean scores for each internet skill were high (above 4 out of 5) for all skills apart from Creative (mean of 3.08 for students and 3.10 for faculty). There were no large differences between student and faculty scores across the five skills. Qualitative results supported survey findings with a deeper investigation into topics such as online professionalism, use of licencing and mobile application development. Needs based skills training and support were highlighted as areas for faculty development. CONCLUSION: Both medical educators and students tend to have similar competencies with respect to internet skills. When implementing online and distance learning methodologies however, medical schools need to ensure appropriate skills training and support for faculty as well as providing targeted training to improve the creative skills of both their educators and students.

Barriers and solutions to online learning in medical education - an integrative review.

BACKGROUND: The aim of this study is to review the literature on known barriers and solutions that face educators when developing and implementing online learning programs for medical students and postgraduate trainees. METHODS: An integrative review was conducted over a three-month period by an inter-institutional research team. The search included ScienceDirect, Scopus, BioMedical, PubMed, Medline (EBSCO & Ovid), ERIC, LISA, EBSCO, Google Scholar, ProQuest A&I, ProQuest UK & Ireland, UL Institutional Repository (IR), UCDIR and the All Aboard Report. Search terms included online learning, medical educators, development, barriers, solutions and digital literacy. The search was carried out by two reviewers. Titles and abstracts were screened independently and reviewed with inclusion/exclusion criteria. A consensus was drawn on which articles were included. Data appraisal was performed using the Critical Appraisal Skills Programme (CASP) Qualitative Research Checklist and NHMRC Appraisal Evidence Matrix. Data extraction was completed using the Cochrane Data Extraction Form and a modified extraction tool. RESULTS: Of the 3101 abstracts identified from the search, ten full-text papers met the inclusion criteria. Data extraction was completed on seven papers of high methodological quality and on three lower quality papers. Findings suggest that the key barriers which affect the development and implementation of online learning in medical education include time constraints, poor technical skills, inadequate infrastructure, absence of institutional strategies and support and negative attitudes of all involved. Solutions to these include improved educator skills, incentives and reward for the time involved with development and delivery of online content, improved institutional strategies and support and positive attitude amongst all those involved in the development and delivery of online content. CONCLUSION: This review has identified barriers and solutions amongst medical educators to the implementation of online learning in medical education. Results can be used to inform institutional and educator practice in the development of further online learning.

What can we learn from problem-based learning tutors at a graduate entry medical school? A mixed method approach.

Problem-based learning (PBL) has been adopted by many medical schools as an innovative method to deliver an integrated medical curriculum since its inception at McMaster University (Dornan et al., Med Educ 39(2):163-170, 2005; Finucane et al., Med Educ 35(1):56-61, 2001; Barrows, Tutorials in problem-based learning: A new direction in teaching the health professions, 1984). The student experience in PBL has been explored in detail (Merriam, New Directions for Adult and Continuing Education 89: 3-13, 2001; Azer, Kaohsiung J Med Sci 25(5): 240-249, 2009; Boelens et al., BMC Med Ed 15(1): 84, 2015; Dolmans et al., Med Teach 24(2):173-180, 2002; Lee et al., Med Teach 35(2): e935-e942, 2013) but the tutors who facilitate PBL have valuable insight into how PBL functions and this aspect has not been extensively researched. The integrated curriculum for years 1 and 2 at the Graduate Entry Medical School at the University of Limerick is delivered though problem-based learning (PBL). This programme requires collaborative teamwork between students and the tutors who facilitate small-group tutorial sessions. All PBL tutors at GEMS are medically qualified, with the majority (68%) currently working in clinical practice. METHODS: A mixed-methods approach was adopted, utilising two surveys and follow-up focus groups to fully understand the tutor experience. Thirty-three tutors took part in two online surveys with a response rate of 89%. Thirteen tutors participated in two focus groups. Descriptive analysis was completed on survey data and thematic analysis on focus group discussions which highlighted five main themes. RESULTS: Tutors reported challenges with managing group dynamics, development of confidence in tutoring with experience and a willingness to learn from peers to improve practice. Findings are in keeping with previously published work. Results also identified several less commonly discussed issues impacting student engagement in PBL including the use of mobile device technology, unauthorised access to learning objectives and PBL cases, and the importance and need for professional development amongst tutors, including the impact of tutoring on clinical practice. This study revealed that experienced tutors spend considerable time preparing for PBL tutorials in the basic sciences and that this input is rewarded by the benefits it brings to their clinical practice. CONCLUSIONS: Understanding PBL from the tutor's perspective reveals valuable insights which can inform ongoing tutor development and support. Limited research exists in the area of PBL tutor's experiences which may be of interest to medical educators, clinicians and the wider medical community. Findings highlight the value of shared tutor experiences as a resource that can be capitalised on to benefit both novice and experienced tutors.

Medical school clinical placements - the optimal method for assessing the clinical educational environment from a graduate entry perspective.

BACKGROUND: Educational environment is a strong determinant of student satisfaction and achievement. The learning environments of medical students on clinical placements are busy workplaces, composed of many variables. There is no universally accepted method of evaluating the clinical learning environment, nor is there consensus on what concepts or aspects should be measured. The aims of this study were to compare the Dundee ready educational environment measure (DREEM - the current de facto standard) and the more recently developed Manchester clinical placement index (MCPI) for the assessment of the clinical learning environment in a graduate entry medical student cohort by correlating the scores of each and analysing free text comments. This study also explored student perceptionof how the clinical educational environment is assessed. METHODS: An online, anonymous survey comprising of both the DREEM and MCPI instruments was delivered to students on clinical placement in a graduate entry medical school. Additional questions explored students' perceptions of instruments for giving feedback. Numeric variables (DREEM score, MCPI score, ratings) were tested for normality and summarised. Pearson's correlation coefficient was used to measure the strength of the association between total DREEM score and total MCPI scores. Thematic analysis was used to analyse the free text comments. RESULTS: The overall response rate to the questionnaire was 67% (n = 180), with a completed response rate for the MCPI of 60% (n = 161) and for the DREEM of 58% (n = 154). There was a strong, positive correlation between total DREEM and MCPI scores (r = 0.71, p < 0.001). On a scale of 0 to 7, the mean rating for how worthwhile students found completing the DREEM was 3.27 (SD 1.41) and for the MCPI was 3.49 (SD 1.57). 'Finding balance' and 'learning at work' were among the themes to emerge from analysis of free text comments. CONCLUSIONS: The present study confirms that DREEM and MCPI total scores are strongly correlated. Graduate entry students tended to favour this method of evaluation over the DREEM with the MCPI prompting rich description of the clinical learning environment. Further study is warranted to determine if this finding is transferable to all clinical medical student cohorts.

MR elastography to measure the effects of cancer and pathology fixation on prostate biomechanics, and comparison with T 1, T 2 and ADC.

MRI is under evaluation for image-guided intervention for prostate cancer. The sensitivity and specificity of MRI parameters is determined via correlation with the gold-standard of histopathology. Whole-mount histopathology of prostatectomy specimens can be digitally registered to in vivo imaging for correlation. When biomechanical-based deformable registration is employed to account for deformation during histopathology processing, the ex vivo biomechanical properties are required. However, these properties are altered by pathology fixation, and vary with disease. Hence, this study employs magnetic resonance elastography (MRE) to measure ex vivo prostate biomechanical properties before and after fixation. A quasi-static MRE method was employed to measure high resolution maps of Young's modulus (E) before and after fixation of canine prostate and prostatectomy specimens (n = 4) from prostate cancer patients who had previously received radiation therapy. For comparison, T 1, T 2 and apparent diffusion coefficient (ADC) were measured in parallel. E (kPa) varied across clinical anatomy and for histopathology-identified tumor: peripheral zone: 99(±22), central gland: 48(±37), tumor: 85(±53), and increased consistently with fixation (factor of 11 ± 5; p < 0.02). T 2 decreased consistently with fixation, while changes in T 1 and ADC were more complex and inconsistent. The biomechanics of the clinical prostate specimens varied greatly with fixation, and to a lesser extent with disease and anatomy. The data obtained will improve the precision of prostate pathology correlation, leading to more accurate disease detection and targeting.

Evaluation of wave delivery methodology for brain MRE: Insights from computational simulations.

PURPOSE: MR elastography (MRE) of the brain is being explored as a biomarker of neurodegenerative disease such as dementia. However, MRE measures for healthy brain have varied widely. Differing wave delivery methodologies may have influenced this, hence finite element-based simulations were performed to explore this possibility. METHODS: The natural frequencies of a series of cranial models were calculated, and MRE-associated vibration was simulated for different wave delivery methods at varying frequency, using simple isotropic viscoelastic material models for the brain. Displacement fields and the corresponding brain constitutive properties estimated by standard inversion techniques were compared across delivery methods and frequencies. RESULTS: The delivery methods produced widely different MRE displacement fields and inversions. Furthermore, resonances at natural frequencies influenced the displacement patterns. Consequently, some delivery methods led to lower inversion errors than others, and the error on the storage modulus varied by up to 11% between methods. CONCLUSION: Wave delivery has a considerable impact on brain MRE reliability. Assuming small variations in brain biomechanics, as recently reported to accompany neurodegenerative disease (e.g., 7% for Alzheimer's disease), the effect of wave delivery is important. Hence, a consensus should be established on a consistent methodology to ensure diagnostic and prognostic consistency. Magn Reson Med 78:341-356, 2017. © 2016 International Society for Magnetic Resonance in Medicine.

Push and stay factors affecting Irish medical student migration intentions.

BACKGROUND: A significant proportion of medical students in Ireland have demonstrated strong intentions to migrate following their graduation. Factors influencing these intentions are poorly understood. Our study aimed to investigate 'push' and 'stay' factors that may influence the migration plans of medical students. METHODS: Cross-sectional survey of 2273 medical students in Ireland using a mixed methods approach. Survey was completed by 2273 medical students, of which 263 provided free text data that are analysed in this paper. RESULTS: Identified push factors include negative perception regarding career opportunities, working conditions and lifestyle, while family was the only identified strong stay factor. Qualitative analysis of free text responses revealed themes that included training, career, personal and financial factors. CONCLUSION: This study has provided insight into the factors that influence medical student migration intentions. There is a strong need for all stakeholders to collectively discuss and engage in possible solutions.

Relevance of anatomy to medical education and clinical practice: perspectives of medical students, clinicians, and educators.

INTRODUCTION: Against a backdrop of ever-changing diagnostic and treatment modalities, stakeholder perceptions (medical students, clinicians, anatomy educators) are crucial for the design of an anatomy curriculum which fulfils the criteria required for safe medical practice. This study compared perceptions of students, practising clinicians, and anatomy educators with respect to the relevance of anatomy education to medicine. METHODS: A quantitative survey was administered to undergraduate entry (n = 352) and graduate entry students (n = 219) at two Irish medical schools, recently graduated Irish clinicians (n = 146), and anatomy educators based in Irish and British medical schools (n = 30). Areas addressed included the association of anatomy with medical education and clinical practice, mode of instruction, and curriculum duration. RESULTS: Graduate-entry students were less likely to associate anatomy with the development of professionalism, teamwork skills, or improved awareness of ethics in medicine. Clinicians highlighted the challenge of tailoring anatomy education to increase student readiness to function effectively in a clinical role. Anatomy educators indicated dissatisfaction with the time available for anatomy within medical curricula, and were equivocal about whether curriculum content should be responsive to societal feedback. CONCLUSIONS: The group differences identified in the current study highlight areas and requirements which medical education curriculum developers should be sensitive to when designing anatomy courses.