Quantitative 31P magnetic resonance imaging on pathologic rat bones by ZTE at 7T.

BACKGROUND: Osteoporosis is characterized by low bone mineral density (BMD), which predisposes individuals to frequent fragility fractures. Quantitative BMD measurements can potentially help distinguish bone pathologies and allow clinicians to provide disease-relieving therapies. Our group has developed non-invasive and non-ionizing magnetic resonance imaging (MRI) techniques to measure bone mineral density quantitatively. Dual-energy X-ray Absorptiometry (DXA) is a clinically approved non-invasive modality to diagnose osteoporosis but has associated disadvantages and limitations. PURPOSE: Evaluate the clinical feasibility of phosphorus (31P) MRI as a non-invasive and non-ionizing medical diagnostic tool to compute bone mineral density to help differentiate between different metabolic bone diseases. MATERIALS AND METHODS: Fifteen ex-vivo rat bones in three groups [control, ovariectomized (osteoporosis), and vitamin-D deficient (osteomalacia - hypo-mineralized) were scanned to compute BMD. A double-tuned (1H/31P) transmit-receive single RF coil was custom-designed and in-house-built with a better filling factor and strong radiofrequency (B1) field to acquire solid-state 31P MR images from rat femurs with an optimum signal-to-noise ratio (SNR). Micro-computed tomography (µCT) and gold-standard gravimetric analyses were performed to compare and validate MRI-derived bone mineral densities. RESULTS: Three-dimensional 31P MR images of rat bones were obtained with a zero-echo-time (ZTE) sequence with 468 µm spatial resolution and 12-17 SNR on a Bruker 7 T Biospec having multinuclear capability. BMD was measured quantitatively on cortical and trabecular bones with a known standard reference. A strong positive correlation (R = 0.99) and a slope close to 1 in phantom measurements indicate that the densities measured by 31P ZTE MRI are close to the physical densities in computing quantitative BMD. The 31P NMR properties (resonance linewidth of 4 kHz and T1 of 67 s) of ex-vivo rat bones were measured, and 31P ZTE imaging parameters were optimized. The BMD results obtained from MRI are in good agreement with µCT and gravimetry results. CONCLUSION: Quantitative measurements of BMD on ex-vivo rat femurs were successfully conducted on a 7 T preclinical scanner. This study suggests that quantitative measurements of BMD are feasible on humans in clinical MRI with suitable hardware, RF coils, and pulse sequences with optimized parameters within an acceptable scan time since human femurs are approximately ten times larger than rat femurs. As MRI provides quantitative in-vivo data, various systemic musculoskeletal conditions can be diagnosed potentially in humans.

Pre-deployment programmes for building resilience in military and frontline emergency service personnel.

BACKGROUND: Military personnel and frontline emergency workers may be exposed to events that have the potential to precipitate negative mental health outcomes such as depression, symptoms of post-traumatic stress and even post-traumatic stress disorder (PTSD). Programmes have been designed to build psychological resilience before staff are deployed into the field. This review presents a synthesis of the literature on these "pre-deployment resilience-building programmes". OBJECTIVES: The objective of this review was to assess the effectiveness of programmes that seek to build resilience to potentially traumatic events among military and frontline emergency service personnel prior to their deployment. These resilience programmes were compared to other interventions, treatment as usual or no intervention. SEARCH METHODS: Studies were identified through searches of electronic databases including Ovid MEDLINE, Embase, PsycINFO, Web of Science and Google Scholar. The initial search took place in January 2019, with an updated search completed at the end of September 2020. SELECTION CRITERIA: Only studies that used a randomised controlled trial (RCT)/cluster-RCT methodology were included. The programmes being evaluated must have sought to build resilience prior to exposure to trauma. Study participants must have been 18 years or older and be military personnel or frontline emergency workers. DATA COLLECTION AND ANALYSIS: Studies that met the inclusion criteria were assembled. Data extracted included methods, participants' details, intervention details, comparator details, and information on outcomes. The primary outcomes of interest were resilience, symptoms of post-traumatic stress and PTSD. Secondary outcomes of interest included acute stress disorder, depression, social support, coping skills, emotional flexibility, self-efficacy, social functioning, subjective levels of aggression, quality of sleep, quality of life and stress. Assessment of risk of bias was also completed. A total of 28 studies were included in a narrative synthesis of results. MAIN RESULTS: All 28 included studies compared an experimental resilience building intervention versus a control or no intervention. There was a wide range of therapeutic modalities used, including cognitive behavioural therapy (CBT) informed programmes, biofeedback based programmes, stress-management programmes, mindfulness and relaxation programmes, neuropsychological-based programmes, and psychoeducational-informed programmes. The main outcomes are specified here, secondary outcomes such as depression, social support, coping skills, self-efficacy, subjective levels of aggression and stress are reported in text. No studies reported on the following pre-specified outcomes; acute stress disorder, emotional flexibility, social functioning, quality of sleep and quality of life. Resilience Eight studies reported resilience as an outcome. We narratively synthesised the data from these studies and our findings show that five of these interventions had success in building resilience in their respective samples. Two of the studies that reported significant results utilised a CBT approach to build resilience, while the other three successful programmes were mindfulness-based interventions. Symptoms of post-traumatic stress Our narrative synthesis of results included eight studies. Two of the eight studies produced significant reductions in symptoms of post traumatic stress compared to controls. These interventions used neuropsychological and biofeedback intervention models respectively. PTSD caseness Four studies reported PTSD caseness as an outcome. Our narrative synthesis of results suggests that evidence is mixed as to the effectiveness of these interventions in reducing clinical diagnosis of PTSD. One study of a neuropsychology-orientated Attention Bias Modification Training (AMBT) programme had success in reducing both symptoms of post-traumatic stress and numbers of participants receiving a diagnosis of PTSD. A stress-management programme reported that, when baseline differences in rates of pre-deployment mental health issues were controlled for, participants in the control condition were at 6.9 times the risk of a diagnosis of PTSD when compared to the intervention group. Given the diversity of intervention designs and theoretical orientations used (which included stress-management, neuropsychological and psychoeducational programmes), a definitive statement on the efficacy of pre-deployment programmes at reducing symptoms of post-traumatic stress and PTSD cannot be confidently offered. AUTHORS' CONCLUSIONS: While a number of evaluations of relevant programmes have been published, the quality of these evaluations limits our ability to determine if resilience-building programmes 'work' in terms of preventing negative outcomes such as depression, symptoms of post-traumatic stress and diagnoses of PTSD. Based on our findings we recommend that future research should: a) report pre-/post-means and standard deviation scores for scales used within respective studies, b) take the form of large, RCTs with protocols published in advance, and c) seek to measure defined psychological facets such as resilience, PTSD and stress, and measure these concepts using established psychometric tools. This will provide more certainty in future assessments of the evidence base. From a clinical implications point of view, overall there is mixed evidence that the interventions included in this review are effective at safe guarding military personnel or frontline emergency workers from experiencing negative mental health outcomes, including PTSD, following exposure to potentially traumatic events. Based on this, practitioners seeking to build resilience in their personnel need to be aware of the limitations of the evidence base. Practitioners should have modest expectations in relation to the efficacy of resilience-building programmes as a prophylactic approach to employment-related critical incident traumas.

Development and initial validation of the institutional child abuse processes and coping inventory among a sample of Irish adult survivors of institutional abuse.

OBJECTIVE: To develop a psychometric instrument to evaluate psychological processes associated with institutional abuse and coping strategies used to deal with such abuse. METHODS: As part of a comprehensive assessment protocol, an inventory containing theoretically derived multi-item rational scales which assessed institutional abuse-related psychological processes and coping strategies were administered to 247 Irish adult survivors of institutional child abuse. Exploratory and confirmatory factor analyses were used to derive 6-factor scales, the reliability and validity of which were assessed. RESULTS: Factor scales to assess the following constructs were developed (1) traumatization, (2) re-enactment, (3) spiritual disengagement, (4) positive coping, (5) coping by complying, and (6) avoidant coping. There were varying degrees of support for the validity of the scales with most support for the traumatization and re-enactment scales. CONCLUSIONS: The Institutional Child Abuse Processes and Coping Inventory (ICAPCI), particularly its traumatization and re-enactment scales, may be used in future research on adult survivors of institutional child abuse because they are currently the only scales that have been developed with this population to provide reliable and valid assessments of these constructs. PRACTICE IMPLICATIONS: The ICAPCI may be used, cautiously, to assess adult survivors of institutional child abuse.