Performing MRI on patients with MRI-conditional and non-conditional cardiac implantable electronic devices: an update for radiologists.

Pacemakers and implantable cardioverter defibrillators are commonly encountered in clinical practice, and entails special consideration when magnetic resonance imaging (MRI) is required. It is estimated that 50-75% of patients with cardiac implantable electronic devices (CIED) will have an indication for MRI during their lifetime. Radiologists may want to recommend MRI or may be consulted about the need to perform MRI in a patient with a CIED, at which point they may need to approve or at least provide guidance as to whether MRI may be performed safely. Even in situations where final clearance will not be provided by the radiologist, he or she can provide valuable information by reviewing radiographs and determining (a) whether a device is MRI-conditional and MRI may ultimately be permitted, (b) is not MRI-conditional and MRI using the standard workflow will therefore not be approved, or (c) when additional information will clearly be required. CIED identification and verification of leads can be accomplished through review of the medical record and/or evaluation of a chest radiograph. In patients with MRI-conditional CIEDs (as well as with legacy CIEDs in those institutions that perform MRI of these patients), specific imaging protocols must be adhered to in order to prevent death or injury to the patient or damage to the device. In this update, we provide details regarding the above topics and provide an algorithm for integrating this information into a clinical workflow to efficiently triage patients with CIEDs who are being considered for MRI.

Near-Term Decrease in Brain Volume following Mild Traumatic Injury Is Detectible in the Context of Preinjury Volumetric Stability: Neurobiologic Insights from Analysis of Historical Imaging Examinations.

BACKGROUND AND PURPOSE: Neurodegeneration after mild traumatic brain injury may manifest as decreasing regional brain volume that evolves from months to years following mild traumatic brain injury and is associated with worse clinical outcomes. We hypothesized that quantitative brain volume derived from CT of the head, performed for clinical indications during routine care, would change with time and provide insights into the putative neuroinflammatory response to mild traumatic brain injury. MATERIALS AND METHODS: We searched the electronic medical record of our institution for NCCTs of the head performed in patients with mild traumatic brain injury and included those who also underwent NCCTs of the head 1 month to 1 year before and after mild traumatic brain injury for an indication unrelated to trauma. Controls underwent 3 sequential NCCTs of the head with indications unrelated to trauma. The whole-brain and intracranial volume groups were computed using ITK-SNAP. Brain volumes normalized to intracranial volumes were compared across time points using the Wilcoxon signed-rank test. RESULTS: We identified 48 patients from 2005 to 2015 who underwent NCCTs of the head in the emergency department for mild traumatic brain injury and had NCCTs of the head performed both before and after mild traumatic brain injury. Median normalized brain volumes significantly decreased on the follow-up study post-mild traumatic brain injury (0.86 versus 0.84, P < .001) and were similar compared with pre-mild traumatic brain injury studies (0.87 versus 0.86, P = .927). There was no significant difference between normalized brain volumes in the 48 controls. CONCLUSIONS: A decrease in brain volume following mild traumatic brain injury is detectable on CT and is not seen in similar patients with non-mild traumatic brain injury during a similar timeframe. Given the stability of brain volume before mild traumatic brain injury, CT volume loss may represent the subtle effects of neurodegeneration.

Validation and calibration of HeadCount, a self-report measure for quantifying heading exposure in soccer players.

The long-term effects of repetitive head impacts due to heading are an area of increasing concern, and exposure must be accurately measured; however, the validity of self-report of cumulative soccer heading is not known. In order to validate HeadCount, a 2-week recall questionnaire, the number of player-reported headers was compared to the number of headers observed by trained raters for a men's and a women's collegiate soccer teams during an entire season of competitive play using Spearman's correlations and intraclass correlation coefficients (ICCs), and calibrated using a generalized estimating equation. The average Spearman's rho was 0.85 for men and 0.79 for women. The average ICC was 0.75 in men and 0.38 in women. The calibration analysis demonstrated that men tend to report heading accurately while women tend to overestimate. HeadCount is a valid instrument for tracking heading behaviour, but may have to be calibrated in women.

Bidirectional Changes in Anisotropy Are Associated with Outcomes in Mild Traumatic Brain Injury.

BACKGROUND AND PURPOSE: Mild traumatic brain injury results in a heterogeneous constellation of deficits and symptoms that persist in a subset of patients. This prospective longitudinal study identifies early diffusion tensor imaging biomarkers of mild traumatic brain injury that significantly relate to outcomes at 1 year following injury. MATERIALS AND METHODS: DTI was performed on 39 subjects with mild traumatic brain injury within 16 days of injury and 40 controls; 26 subjects with mild traumatic brain injury returned for follow-up at 1 year. We identified subject-specific regions of abnormally high and low fractional anisotropy and calculated mean fractional anisotropy, axial diffusivity, radial diffusivity, and mean diffusivity across all white matter voxels brain-wide and each of several white matter regions. Assessment of cognitive performance and symptom burden was performed at 1 year. RESULTS: Significant associations of brain-wide DTI measures and outcomes included the following: mean radial diffusivity and mean diffusivity with memory; and mean fractional anisotropy, radial diffusivity, and mean diffusivity with health-related quality of life. Significant differences in outcomes were found between subjects with and without abnormally high fractional anisotropy for the following white matter regions and outcome measures: left frontal lobe and left temporal lobe with attention at 1 year, left and right cerebelli with somatic postconcussion symptoms at 1 year, and right thalamus with emotional postconcussion symptoms at 1 year. CONCLUSIONS: Individualized assessment of DTI abnormalities significantly relates to long-term outcomes in mild traumatic brain injury. Abnormally high fractional anisotropy is significantly associated with better outcomes and might represent an imaging correlate of postinjury compensatory processes.

Utility of diffusion tensor imaging in evaluation of the peritumoral region in patients with primary and metastatic brain tumors.

In the brain, diffusion tensor imaging is a useful tool for defining white matter anatomy, planning a surgical approach to space-occupying lesions, and characterizing tumors, including distinguishing primary tumors from metastases. Recent studies have attempted, with varying success, to use DTI to define the extent of tumor microinfiltration beyond the apparent borders on T2-weighted imaging. In the present review, we discuss the current state of research on the utility of DTI for evaluating the peritumoral region of brain tumors.

A decade of DTI in traumatic brain injury: 10 years and 100 articles later.

SUMMARY: The past decade has seen an increase in the number of articles reporting the use of DTI to detect brain abnormalities in patients with traumatic brain injury. DTI is well-suited to the interrogation of white matter microstructure, the most important location of pathology in TBI. Additionally, studies in animal models have demonstrated the correlation of DTI findings and TBI pathology. One hundred articles met the inclusion criteria for this quantitative literature review. Despite significant variability in sample characteristics, technical aspects of imaging, and analysis approaches, the consensus is that DTI effectively differentiates patients with TBI and controls, regardless of the severity and timeframe following injury. Furthermore, many have established a relationship between DTI measures and TBI outcomes. However, the heterogeneity of specific outcome measures used limits interpretation of the literature. Similarly, few longitudinal studies have been performed, limiting inferences regarding the long-term predictive utility of DTI. Larger longitudinal studies, using standardized imaging, analysis approaches, and outcome measures will help realize the promise of DTI as a prognostic tool in the care of patients with TBI.

Hippocampal correlates of pain in healthy elderly adults: a pilot study.

BACKGROUND: Few neuroimaging investigations of pain in elderly adults have focused on the hippocampus, a brain structure involved in nociceptive processing that is also subject to involution associated with dementing disorders. The goal of this pilot study was to examine MRI- and magnetic resonance spectroscopy (MRS)-derived hippocampal correlates of pain in older adults. METHODS: A subset of 20 nondemented older adults was drawn from the Einstein Aging Study, a community-based sample from the Bronx, NY. Pain was measured on 3 time scales: 1) acute pain right now (pain severity); 2) pain over the past 4 weeks (Short Form-36 Bodily Pain); 3) chronic pain over the past 3 months (Total Pain Index). Hippocampal data included volume data normalized to midsagittal area and N-acetylaspartate to creatine ratios (NAA/Cr). RESULTS: Smaller hippocampal volume was associated with higher ratings on the Short Form-36 Bodily Pain (r(s) = 0.52, p = 0.02) and a nonsignificant trend was noted for higher ratings of acute pain severity (r(s) = -0.44, p = 0.06). Lower levels of hippocampal NAA/Cr were associated with higher acute pain severity (r(s) = -0.45, p = 0.05). Individuals with chronic pain had a nonsignificant trend for smaller hippocampal volumes (t = 2.00, p = 0.06) and lower levels of hippocampal NAA/Cr (t = 1.71, p = 0.10). CONCLUSIONS: Older adults who report more severe acute or chronic pain have smaller hippocampal volumes and lower levels of hippocampal N-acetylaspartate/creatine, a marker of neuronal integrity. Future studies should consider the role of the hippocampus and other brain structures in the development and experience of pain in healthy elderly and individuals with Alzheimer disease.

Deep brain reversible encephalopathy: association with secondary antiphospholipid antibody syndrome.

We present a case of a patient with systemic lupus erythematosus and secondary antiphospholipid syndrome. The patient presented with acute right cerebellar infarction and clinical and imaging evidence of brain stem and bilateral thalamic encephalopathy that resolved completely.

The importance of children's illness beliefs: the Children's Illness Perception Questionnaire (CIPQ) as a reliable assessment tool for eczema and asthma.

A lack of information about disease in children can lead to erroneous views such as children believing that hospital admittance or the presence of a disease is a punishment for a perceived wrong. There has thus far been no standard tool available to measure children's illness conceptualizations from a Leventhalian framework. Three groups of children with eczema, asthma and eczema and asthma between the ages of 7 and 12 years of age were recruited. Children were given the Children's Illness Perception Questionnaire (CIPQ), a 26-item instrument adapted from the Illness Perception Questionnaire for adults. A Kuder - Richardson 20 test of reliability for dichotomous data was performed allowing an estimate of the internal consistency of the measurement scales. It can be seen that, for all three illness groups, internal consistency is acceptable for the timeline and consequences scale. The cure/control scale, however, was not internally consistent for any illness group. As health professionals, we need to develop the means to further understand how paediatric illness beliefs relate to specific disease types, age and psychosocial factors and the utility of this instrument is discussed within this context.

A randomized controlled trial of laser treatment among hirsute women with polycystic ovary syndrome.

BACKGROUND: Facial hirsutism is one of the characteristic features of polycystic ovary syndrome (PCOS), and this can lead to high levels of depression and anxiety. OBJECTIVES: To evaluate the impact of laser treatment on the severity of facial hirsutism and on psychological morbidity in women with PCOS. METHODS: A randomized controlled trial of five high-fluence treatments (intervention) vs. five low-fluence treatments (control) was performed over 6 months in a National Health Service teaching hospital. Subjects were 88 women with facial hirsutism due to PCOS recruited from hospital outpatient clinics and a patient support group in 2001-2002. The main outcomes were self-reported severity of facial hair (measured on a scale of 1-10), depression, anxiety (measured on the Hospital Anxiety and Depression Scale) and quality of life (measured on the WHOQOL-BREF). RESULTS: Self-reported severity of facial hair in the intervention group (n = 51) fell from 7.3 to 3.6 over the 6-month study period; for the control group (n = 37) the corresponding scores were 7.1 and 6.1. The change was significantly greater in the intervention group [ancova F((1,83)) = 24.5, P < 0.05]. Self-reported time spent on hair removal declined from 112 to 21 min per week in the intervention group and from 92 to 56 min in the control group [F((1,80)) = 10.2, P

Exploring the stereochemical requirements for protease inhibition by ureidopeptides.

A novel 'ureidopeptide' substrate analog inhibitor of the HIV-1 protease, created by substitution of a urea for the scissile amide bond of a hexapeptide substrate, was synthesized and tested for inhibition of HIV-1 protease. This inhibitor was designed as a stereochemical mutant of an earlier ureidopeptide inhibitor in which the P1' phenylalanine residue was changed from an l-isomer to a d-isomer. This was done in an attempt to increase binding to the enzyme by compensating for a lengthening of the peptide backbone. The inhibitor was synthesized from two protected tripeptide precursors using an oxidative Hoffmann rearrangement of a C-terminal peptide amide. The new inhibitor was found to inhibit HIV-1 protease with an observed IC(50) of 47 mum.

Nanoscale proteomics.

Efforts to develop a liquid chromatography (LC)/mass spectrometry (MS) technology for ultra-sensitive proteomics studies (i.e., nanoscale proteomics) are described. The approach combines high-efficiency nanoscale LC (separation peak capacity of approximately 10(3); 15-microm-i.d. packed capillaries with flow rates of 20 nL min(-1), the optimal separation linear velocity) with advanced MS, including high-sensitivity and high-resolution Fourier transform ion cyclotron resonance MS, to perform both single-stage MS and tandem MS (MS/MS) proteomic analyses. The technology enables broad protein identification from nanogram-size proteomics samples and allows the characterization of more abundant proteins from sub-picogram-size samples. Protein identification in such studies using MS is demonstrated from <75 zeptomole of a protein. The average proteome measurement throughput is approximately 50 proteins h(-1) using MS/MS during separations, presently requiring approximately 3 h sample(-1). Greater throughput (approximately 300 proteins h(-1)) and improved detection limits providing more comprehensive proteome coverage can be obtained by using the "accurate mass and time" tag approach developed in our laboratory. This approach provides a dynamic range of at least 10(6) for protein relative abundances and an improved basis for quantitation. These capabilities lay the foundation for studies from single or limited numbers of cells.

Summary of final changes to EMTALA regulations.

The Emergency Medical Treatment and Labor Act (EMTALA) was enacted in 1986. Its purpose was to ensure that all individuals receive necessary emergency services from hospitals and not be denied care (i.e., "patient dumping") because of their economic status or lack of insurance. In its application, EMTALA has reduced "patient dumping," but at great cost to hospitals and physicians as an unfunded mandate. Despite 17 years of experience with the law, providers have been uncertain as to where and when, and to whom, the EMTALA obligations apply. The law has also proven to be burdensome and has been interpreted as extending far beyond the hospital emergency room. After reviewing the law for some time, the Centers for Medicare and Medicaid Services (CMS) released its final rules redefining the scope of EMTALA, reaffirming certain guidelines and modifying or clarifying others. The new regulations attempt to restate the parameters of the law as it applies to the emergency department and the hospital, as well as to inpatients and outpatients. The new rules clarify on-call obligations for physicians, confirming guidance issued by CMS in June 2002. This article summarizes the salient features of these new regulations.

Challenges to meet: food and nutrition security in the new millennium.

Before about 1750 there was no substantial secular fall in protein-energy malnutrition (PEM) over large areas, nor reason to expect it. We have since learned that sufficient economic advance (poverty reduction) plus scientific advance (in medicine and food production) are achievable to eliminate mass PEM. The two advances are linked via increased demand for labour, and hence wages and employment, for those formerly too poor to afford adequate food. The extra employment income arises first from smallholder and employee food production, and later, as labour is released, from a wide range of specialised, increasingly non-farm, production, with employment income traded for food. This process eliminated mass hunger in Europe in 1750-1960. Only by 1975 had PEM in the developing world retreated to (very high) 1936-8 levels, but it fell sharply in Asia and Latin America in 1975-1990, due to unprecedented growth in staples yields, smallholder and farm employment income, and hence the poor's purchasing power over food. However, since 1990, poverty reduction has slowed (before reaching most of Africa), alongside much slower-staples yield growth, increasing water shortages, and big shifts of grain and land from man to farm animals. These trends prefigure declining progress against PEM in coming decades, unless there is renewed, employment-intensive food-staples-yield growth. That process requires reorienting crop biotechnology and water science towards the needs of small tropical farmers and their staple food crops, and shifting land towards them. Mass PEM is indeed largely due to inadequate 'food entitlements' by the hungry, but will not be remedied without growth in their employment, based on further advances in food-staples yields per unit land and water. Recent evidence suggests that early PEM may increase lifelong risks of infection and/or degenerative disease. This factor would increase the 'squeeze' on health resources in low-income countries, between the diseases of poverty and those of old age. That situation increases the need to readdress PEM by renewed progress in food production and land distribution.

High-throughput peptide identification from protein digests using data-dependent multiplexed tandem FTICR mass spectrometry coupled with capillary liquid chromatography.

Tandem mass spectrometry (MS/MS) plays an important role in the unambiguous identification and structural elucidation of biomolecules. In contrast to conventional MS/MS approaches for protein identification where an individual polypeptide is sequentially selected and dissociated, a multiplexed-MS/MS approach increases throughput by selecting several peptides for simultaneous dissociation using either infrared multiphoton dissociation (IRMPD) or multiple frequency sustained off-resonance irradiation (SORI) collisionally induced dissociation (CID). The high mass measurement accuracy and resolution of FTICR combined with knowledge of peptide dissociation pathways allows the fragments arising from several different parent ions to be assigned. Herein we report the application of multiplexed-MS/MS coupled with on-line separations for the identification of peptides present in complex mixtures (i.e., whole cell lysate digests). Software was developed to enable "on-the-fly" data-dependent peak selection of a subset of polypeptides from each FTICR MS acquisition. In the subsequent MS/MS acquisitions, several coeluting peptides were fragmented simultaneously using either IRMPD or SORI-CID techniques. The utility of this approach has been demonstrated using a bovine serum albumin tryptic digest separated by capillary LC where multiple peptides were readily identified in single MS/MS acquisitions. We also present initial results from multiplexed-MS/MS analysis of a D. radiodurans whole cell digest to illustrate the utility of this approach for high-throughput analysis of a bacterial proteome.