MR perfusion

PURPOSE: To evaluate the ability of intravoxel incoherent motion (IVIM), a perfusion-weighted imaging technique, to differentiate microcirculation changes in the spinal cord of patients with multiple sclerosis (MS) compared with healthy individuals. METHODS: Fifteen healthy individuals and 15 individuals with MS underwent IVIM magnetic resonance (MR) imaging using a 3 T scanner with 2-D axial gradient recalled echo and 2-D axial diffusion-weighted imaging (DWI) sequences...

PURPOSE: To determine the usefulness of multiparametric magnetic resonance (MR) quantitative imaging in characterizing the kidneys in systemic sclerosis (SSc) patients. MATERIAL AND METHODS: Forty-six SSc patients (47.9 ± 12.8 years, 40 females) and 22 age- and sex- matched healthy volunteers (46.1 ± 13.8 years, 20 females) were recruited and underwent renal MR imaging by acquiring blood oxygen level dependent and saturated multi-delay renal arterial spin labeling (SAMURAI) sequences...

Intracranial compliance (ICC) refers to the change in intracranial volume per unit change in intracranial pressure (ICP). Magnetic resonance elastography (MRE) quantifies brain stiffness by measuring the shear modulus. Our objective is to investigate the relationship between ICC and brain stiffness through fluid-structure interaction (FSI) simulation, and to explore the feasibility of using MRE to assess ICC based on brain stiffness. This is invaluable due to the clinical importance of ICC, as well as the fast and non-invasive nature of the MRE procedure...

Lipid emulsion therapy (LET) is the intravenous administration of lipid solution for parenteral alimentation, especially in preterm infants and adults with debilitating illnesses. It has also been used in attempts of detoxification in suspected cases of drug overdose. Whether this interferes with circulation and/or perfusion is debatable, and it is suggested that it may interfere with coagulation process. The emulsifying agent has been identified microscopically mainly in the lungs of these patients, with rare reports in adults and even more rare ones in the brain; however, although it is rarely reported in other organs, to our knowledge, no reports of gross autopsy findings in the brain are available in the English literature, nor are there reports of pathologic findings after lipid emulsion therapy administration for drug toxicity...

Sequestration of infected red blood cells (iRBCs) in the microcirculation is a hallmark of cerebral malaria (CM) in post-mortem human brains. It remains controversial how this might be linked to the different disease manifestations, in particular brain swelling leading to brain herniation and death. The main hypotheses focus on iRBC-triggered inflammation and mechanical obstruction of blood flow. Here, we test these hypotheses using murine models of experimental CM (ECM), SPECT-imaging of radiolabeled iRBCs and cerebral perfusion, MR-angiography, q-PCR, and immunohistochemistry...

BACKGROUND: Acute coronary artery obstruction is a rare but lethal complication of surgical aortic valve replacement (SAVR), which may be caused by embolization of resected native tissue such as calcium plaque, thrombus, or perivalvular aortic tissue like fat embolus. Coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) are the main treatment modalities. PCI is less invasive, but it is difficult to determine its feasibility intraoperatively. CASE PRESENTATION: We report an 86-year-old woman who had asymptomatic severe aortic stenosis...

Postural orthostatic tachycardia syndrome (POTS) is characterized by an excessive heart rate (HR) response upon standing and symptoms indicative of inadequate cerebral perfusion. We tested the hypothesis that during lower body negative pressure (LBNP), individuals with POTS would have larger decreases in cardiac and cerebrovascular function measured using magnetic resonance (MR) imaging. Eleven patients with POTS and 10 healthy controls were studied at rest and during 20 min of -25 mmHg LBNP. Biventricular volumes, stroke volume (SV), cardiac output (Qc), and HR were determined by cardiac MR...

BACKGROUND: Although the amygdala has structural and functional abnormalities in Chronic Migraine (CM), less is known about the altered perfusion of the amygdala in CM. OBJECTIVE: The current study aimed to assess amygdala perfusion in CM using a contrast agent-free and quantitative approach. METHODS: 15 Normal Controls (NC) and 13 patients with CM during the migraine interval were assessed for brain structure and subjected to 3D Pseudo- Continuous Arterial Spin Labeling (3D-PCASL) MR imaging...

Cerebrovascular impairment represents one of the main causes of death worldwide with a mortality rate of 5.5 million per year. The disability of 50% of surviving patients has high social impacts and costs in long period treatment for national healthcare systems. For these reasons, the efficacious clinical treatment of patients, with brain ischemic stroke, remains a medical need. To this aim, a liposome nanomedicine, with monosialic ganglioside type 1 (GM1), OX26 (an anti-transferrin receptor antibody), and CDP-choline (a neurotrophic drug) (CDP-choline/OX26Lip) was prepared...

This AJR Expert Panel Narrative explores the current status of advanced MRI and PET techniques for the post-therapeutic response assessment of high-grade adult-type gliomas, focusing on ongoing clinical controversies in current practice. Discussed techniques that complement conventional MRI and aid the differentiation of recurrent tumor from post-treatment effects include DWI and diffusion tensor imaging; perfusion MRI techniques including dynamic susceptibility contrast (DSC), dynamic contrast-enhanced MRI, and arterial spin labeling; MR spectroscopy including assessment of 2-hydroxyglutarate (2HG) concentration; glucose- and amino acid (AA)-based PET; and amide proton transfer imaging...

PURPOSE: To demonstrate hyperpolarization of 15 N-caffeine and report exploratory findings as a potential probe of liver function and perfusion. METHODS: An amorphous formulation of [1,3-15 N2 ]caffeine was developed for hyperpolarization via dissolution dynamic nuclear polarization. Polarizer hardware was augmented to support monitoring of solid-state 15 N MR signals during the buildup of hyperpolarization. Liquid state hyperpolarized 15 N MR signals were obtained in a preclinical 3T magnet by interfacing an external spectrometer console with home-built RF surface coils...

Cerebral microdialysis (CMD) catheters allow continuous monitoring of patients' cerebral metabolism in severe traumatic brain injury (TBI). The catheters consist of a terminal semi-permeable membrane that is inserted into the brain's interstitium to allow perfusion fluid to equalize with the surrounding cerebral extracellular environment before being recovered through a central non-porous channel. However, it is unclear how far recovered fluid and suspended metabolites have diffused from within the brain, and therefore what volume or region of brain tissue the analyses of metabolism represent...

Brain tumor diagnostics have significantly evolved with the use of PET and advanced MRI techniques. In addition to anatomical MRI, these modalities may provide valuable information for several clinical applications such as differential diagnosis, delineation of tumor extent, prognostication, differentiation between tumor relapse and treatment-related changes, and the evaluation of response to anticancer therapy. In particular, joint recommendations of the RANO group, the EANO, and major European and American Nuclear Medicine societies highlighted that the additional clinical value of radiolabeled amino acids compared to anatomical MRI alone is outstanding and that its widespread clinical use should be supported...

Microfluidic blood flow models have been instrumental to study the functions of blood platelets in hemostasis and arterial thrombosis. However, they are not suited to investigate the interactions of platelets with the foreign surfaces of medical devices such as stents, mainly because of the dimensions and geometry of the microfluidic channels. Indeed, the channels of microfluidic chips are usually rectangular and rarely exceed 50 to 100 μm in height, impairing the insertion of clinically used stents. To fill this gap, we have developed an original macrofluidic flow system, which precisely reproduces the size and geometry of human vessels and therefore represents a biomimetic perfectly suited to insert a clinical stent and study its interplay with blood cells...

INTRODUCTION AND IMPORTANCE: Multiple sclerosis is known to be associated with both sympathetic and parasympathetic cardiovascular autonomic dysregulation. Thus, patients with multiple sclerosis comorbidity represent a potentially challenging patient population in cardiac surgery, especially in on-pump operations. Despite this, very little is known about the hemodynamics during cardiopulmonary bypass and the optimal perfusion strategy for patients with multiple sclerosis undergoing cardiac operations...

Long-term or post-COVID-19 syndrome (PCS) is a condition that affects people infected with SARS‑CoV‑2, the virus that causes COVID-19. PCS is characterized by a wide range of persistent or new symptoms that last months after the initial infection, such as fatigue, shortness of breath, cognitive dysfunction, and pain. Advanced magnetic resonance (MR) neuroimaging techniques can provide valuable information on the structural and functional changes in the brain associated with PCS as well as potential biomarkers for diagnosis and prognosis...

BACKGROUND AND PURPOSE: MR perfusion has shown value in the evaluation of posttreatment high-grade gliomas, but few studies have shown its impact on the consistency and confidence of neuroradiologists' interpretation in routine clinical practice. We evaluated the impact of adding MR perfusion metrics to conventional contrast-enhanced MR imaging in posttreatment high-grade glioma surveillance imaging. MATERIALS AND METHODS: This retrospective study included 45 adults with high-grade gliomas who had posttreatment perfusion MR imaging...

PURPOSE: Radiation-induced lung injury (RILI) has been shown to alter regional ventilation and perfusion in the lung. However, changes in regional pulmonary gas exchange have not previously been measured. METHODS: Ten patients receiving conventional radiation therapy (RT) for lung cancer underwent pre-RT and 3-month post-RT MRI using an established hyperpolarized-129 Xe gas exchange technique to map lung function. Four patients underwent an additional 8-month post-RT MRI...

Physiological or pathological hypoperfusion of the placenta is one of the main causes of intrauterine growth restriction (IUGR) which poses a significant risk to the health of the fetus and newborn. Tadalafil, a 5-type phosphodiesterase inhibitor, has previously been found to improve the symptoms of IUGR in various clinical studies. Unfortunately, its clinical utility is hindered by its limited water solubility, rapid metabolism, and lack of specific distribution in target tissues rendering tadalafil unable to maintain long-term placental perfusion...

BACKGROUND: Patients with ventricular assist devices (VADs) represent a growing population presenting to Emergency Medical Services (EMS), but little is known about their prehospital care. This study aimed to characterize current EMS protocols in the United States for patients with VADs. METHODS: States with state-wide EMS protocols were included. Protocols were obtained from the state EMS website. If not available, the office of the state medical director was contacted...