Project description:Decompression illness in breath-hold diving is a rare dysbaric disease mainly characterized by stroke-like neurological disorders. The early use of DWI-MRI combined with ADC map in suspected cases can help in the early diagnosis and treatment.
Project description:BackgroundEffective January 1, 2021, US hospitals were required to upload information on their chargemaster prices (database of list prices), discounted cash prices (commonly charged to self-pay patients), and payer-specific negotiated prices.ObjectiveExamine how prices vary and are associated with hospital characteristics, market competition, and hospital quality.Design setting and participantsThis observational study used data on 14 common medical services across 1599 hospitals in 2021. Descriptive and regression analyses were used to study price variation. Analyses adjust for hospital characteristics, market competition and state fixed effects.ResultsNinetieth -to-10th-percentile price markups factors (ratios) range between 3.2 and 11.5 for chargemaster; 6.1 and 19.7 for cash; and 6.6 and 30.0 for negotiated prices. Adjusted regression results indicate that hospitals' cash prices are on average 60% ( P <0.01) higher, and list prices are on average 164% ( P <0.01) higher, than negotiated prices. Systematic pricing differences across hospitals were noted, with urban hospitals having 14% ( P <0.01) lower prices than rural hospitals, teaching hospitals having 3% ( P <0.01) higher prices than nonteaching hospitals, and nonprofit hospitals pricing 9% ( P <0.01), and for-profit hospitals 39% ( P <0.01), higher than government owned hospitals. In addition, hospitals that contract with more insurance plans have higher prices, hospitals in more competitive markets have lower prices, and higher quality hospitals have on average 5% ( P <0.01) lower prices than lower quality hospitals.ConclusionsPrices all vary considerably across US hospitals. High quality hospitals are associated with lower pricing across all three sets of prices examined. Hospital price transparency may help consumers better identify hospitals that provide both high quality, and low cost, care.
Project description:In the central nervous system of vertebrates, cell bodies of neurons are often assembled as nuclei or cellular layers that play specific roles as functional units. The purpose of this work was to selectively highlight such cell assemblies by magnetic resonance imaging using signals from water protons that are associated with intracellular paramagnetic ions, while saturating lipid-associated water protons as well as extracellular free water protons. Given the significant correlation between image signal intensity and water proton density, the high signal intensities observed for such cell assemblies must be attributed to their abundant paramagnetic-ion-associated water protons. In the hippocampal formation, the technique visualized cell assemblies that were so far not depicted in human in vivo. In the brainstem, the technique delineated noradrenergic neuron groups such as the locus coeruleus in human and mice in vivo. Their reduced magnetization-transfer ratios together with their prolonged relaxation times compared to other gray matter indicate that the source of their high signal intensity is not the presence of T1-shortening molecules, e.g., neuromelanin, but their high water content. Given the general absence of neuromelanin in noradrenergic neurons of rodents, their high signal intensity in mice in vivo further supports this view.
Project description:Although the blood-brain barrier (BBB) was thought to protect the brain from the effects of the immune system, immune cells can nevertheless migrate from the blood to the brain, either as a cause or as a consequence of central nervous system (CNS) diseases, thus contributing to their evolution and outcome. Accordingly, as the interface between the CNS and the peripheral immune system, the BBB is critical during neuroinflammatory processes. In particular, endothelial cells are involved in the brain response to systemic or local inflammatory stimuli by regulating the cellular movement between the circulation and the brain parenchyma. While neuropathological conditions differ in etiology and in the way in which the inflammatory response is mounted and resolved, cellular mechanisms of neuroinflammation are probably similar. Accordingly, neuroinflammation is a hallmark and a decisive player of many CNS diseases. Thus, molecular magnetic resonance imaging (MRI) of inflammatory processes is a central theme of research in several neurological disorders focusing on a set of molecules expressed by endothelial cells, such as adhesion molecules (VCAM-1, ICAM-1, P-selectin, E-selectin, …), which emerge as therapeutic targets and biomarkers for neurological diseases. In this review, we will present the most recent advances in the field of preclinical molecular MRI. Moreover, we will discuss the possible translation of molecular MRI to the clinical setting with a particular emphasis on myeloperoxidase imaging, autologous cell tracking, and targeted iron oxide particles (USPIO, MPIO).
Project description:Background and Purpose- Atrial fibrillation (AF) is associated with dementia independent of clinical stroke. The mechanisms underlying this association remain unclear. In a community-based cohort, the ARIC study (Atherosclerosis Risk in Communities), we evaluated (1) the longitudinal association of incident AF and (2) the cross-sectional association of prevalent AF with brain magnetic resonance imaging (MRI) abnormalities. Methods- The longitudinal analysis included 963 participants (mean age, 73±4.4 years; 62% women; 51% black) without prevalent stroke or AF who underwent a brain MRI in 1993 to 1995 and a second MRI in 2004 to 2006 (mean, 10.6±0.8 years). Outcomes included subclinical cerebral infarctions, sulcal size, ventricular size, and, for the cross-sectional analysis, white matter hyperintensity volume and total brain volume. Results- In the longitudinal analysis, 29 (3.0%) participants developed AF after the first brain MRI. Those who developed AF had higher odds of increase in subclinical cerebral infarctions (odds ratio [OR], 3.08; 95% CI, 1.39-6.83), worsening sulcal grade (OR, 3.56; 95% CI, 1.04-12.2), and worsening ventricular grade (OR, 9.34; 95% CI, 1.24-70.2). In cross-sectional analysis, of 969 participants, 35 (3.6%) had prevalent AF at the time of the 2004 to 2006 MRI scan. Those with AF had greater odds of higher sulcal (OR, 3.9; 95% CI, 1.7-9.1) and ventricular grade (OR, 2.4; 95% CI, 1.0-5.7) after multivariable adjustment and no difference in white matter hyperintensity or total brain volume. Conclusions- AF is independently associated with increase in subclinical cerebral infarction and worsening sulcal and ventricular grade-morphological changes associated with aging and dementia. More research is needed to define the mechanisms underlying AF-related neurodegeneration.
Project description:BackgroundInfantile spasms are an age-specific epileptic disorder. They occur in infancy and early childhood. They can be caused by multiple etiologies. Structural abnormalities represent an important cause of infantile spasms. Brain magnetic resonance imaging (MRI) is one of the integral modalities in the evaluation of this condition.PurposeThe aim of this study is to review and analyze the clinical characteristics and brain MRI findings in a cohort of children diagnosed with infantile spasms.Material and methodsA cohort of fifty-six children diagnosed with infantile spasms in infancy and early childhood was included. All of them underwent brain MRI for evaluation. The study was conducted in the period from January 2016 to January 2020.ResultsFemales comprised 57% of the cohort. The mean age for seizure onset was 5.9 months (SD 2.7). Forty-one patients (73%) had active epilepsy, and 51% were diagnosed with global developmental delay. Consanguinity was present in 59% of the cohort. Most of the follow-up MRIs showed structural abnormalities (84%). Hypoxia was reported in 17% of MRIs. Malformations of cortical development were seen in five patients. Brain MRI findings were normal in 16% of patients, and delayed myelination was seen in nineteen patients. Most of the children with active epilepsy (64%) and developmental delay (82%) had an abnormal brain MRI. It was noticed that abnormal second brain MRIs were more likely to be associated with active epilepsy and developmental delay (p = 0.05).ConclusionsBrain MRI is an integral part of infantile spasms' clinical evaluation. Infantile spasms and abnormal brain MRI can be associated with active epilepsy and global developmental delay.
Project description:Genome wide DNA methylation profiling of normal and tumour prostate samples. The Illumina Infinium MethylationEPIC Human DNA methylation oligonucleotide beads was used to obtain DNA methylation profiles across approximately 850,000 CpGs. Comparative assessment was carried out.
Project description:AimsWe aim to explore whether people with epilepsy have increased white matter hyperintensities (WMHs).MethodsEligible patients were categorized into newly diagnosed epilepsy (NE) and chronic epilepsy (CE); the latter were subdivided to those treated with enzyme-inducing antiepileptic drugs (EIAEDs) with or without non-enzyme-inducing antiepileptic drugs (NEIAEDs) and those with NEIAEDs only. WMHs were measured using age-related white matter changes (ARWMC) scale and compared between patients and healthy control group. Higher scores indicate greater WMH changes. The strengths of associations were estimated as incidence rate ratios (IRRs) with 95% confidence interval (CI).ResultsA total of 217 patients were included in the analysis, of whom 67 had NE, 45 had CE treated with NEIAEDs, and 105 had CE treated with EIAEDs. Age was positively associated with ARWMC score (IRR per year, 1.03; 95%CI, 1.03-1.04, P < 0.001). Compared with the healthy control group (n = 23), all patient groups had higher ARWMC score (P < 0.05). The difference was greatest in patients receiving EIAEDs (IRR, 2.13; 95%CI, 1.22-3.70, P = 0.007).ConclusionsWMHs tended to be observed in people with epilepsy, especially in those treated with EIAEDs. People with epilepsy with white matter changes should be evaluated for stroke risk, particularly if they are receiving EIAEDs.
Project description:BackgroundWe aimed to demonstrate the feasibility of generating high-resolution human brain magnetic resonance imaging (MRI) at 5 Tesla (T) using a quadrature birdcage transmit/48-channel receiver coil assembly.MethodsA quadrature birdcage transmit/48-channel receiver coil assembly was designed for human brain imaging at 5T. The radio frequency (RF) coil assembly was validated by electromagnetic (EM) simulations and phantom imaging experimental studies. The simulated B1+ field inside a human head phantom and inside a human head model generated by the birdcage coils driven in circularly polarized (CP) mode at 3T, 5T and 7T was compared. Signal-to-noise ratio (SNR) maps, the inverse g-factor maps for evaluation of parallel imaging performance, anatomic images, angiography images, vessel wall images and susceptibility weighted images (SWI) were acquired using the RF coil assembly at 5T and compared to those acquired using a 32-channel head coil on a 3T MRI scanner.ResultsFor the EM simulations, 5T MRI provided less RF inhomogeneity compared to that of 7T. In the phantom imaging study, the distributions of the measured B1+ field were consistent with the distributions of the simulated B1+ field. In the human brain imaging study, the average SNR value of the brain in the transversal plane at 5T was 1.6 times of that at 3T. The 48-channel head coil at 5T had higher parallel acceleration capability than the 32-channel head coil at 3T. The anatomic images at 5T also showed higher SNR than those at 3T. Improved delineation of the hippocampus, lenticulostriate arteries, and basilar arteries was observed at 5T compared to 3T. SWI with a higher resolution of 0.3 mm ×0.3 mm ×1.2 mm could be acquired at 5T, which enabled better visualization of small blood vessels compared to that at 3T.Conclusions5T MRI can provide significant SNR improvement compared to that of 3T with less RF inhomogeneity than that of 7T. The ability to obtain high quality in vivo human brain images at 5T using the quadrature birdcage transmit/48-channel receiver coil assembly has significant in clinical and scientific research applications.