A5043207267- Medical Imaging Techniques and Applications
- Advanced MRI Techniques and Applications
- Spine and Intervertebral Disc Pathology
- Radiomics and Machine Learning in Medical Imaging
- Cardiac Imaging and Diagnostics
- Traumatic Brain Injury and Neurovascular Disturbances
- Radiopharmaceutical Chemistry and Applications
- Functional Brain Connectivity Studies
- Advanced X-ray and CT Imaging
- Musculoskeletal pain and rehabilitation
- Veterinary Orthopedics and Neurology
- Advanced Radiotherapy Techniques
- Neurotransmitter Receptor Influence on Behavior
- Atomic and Subatomic Physics Research
- Radiation Dose and Imaging
- Cerebrovascular and Carotid Artery Diseases
- MRI in cancer diagnosis
- Cardiovascular Function and Risk Factors
- Neuroscience and Neuropharmacology Research
- Radiation Detection and Scintillator Technologies
- Optical Imaging and Spectroscopy Techniques
- Cardiovascular and exercise physiology
- Diet and metabolism studies
- EEG and Brain-Computer Interfaces
- Schizophrenia research and treatment
Rigshospitalet
2016-2025
Copenhagen University Hospital
2012-2025
University of Copenhagen
2010-2023
Leo Pharma (Australia)
2021
University of Manchester
2020
Capital Region of Denmark
2011-2017
Glostrup Hospital
2016
Creative Commons
2013
Technical University of Denmark
2013
European Association of Nuclear Medicine
2013
URBAN, J. P. G.; HOLM, S.; MAROUDAS, A.; NACHEMSON, A.Editor(s): CRACCHIOLO, ANDREA III M.D. Author Information
The metabolism of the canine nucleus pulposus was investigated at different oxygen tensions. It found that even high tensions is mainly anaerobic, only approximately 1.5% glucose being converted to carbon dioxide. concentration dependence consumption limited very low Values and lactic acid production were used calculate profiles these substances within pulposus, using a diffusion theory. predicted compared with experimental measurements various positions in disc. good agreement values...
To accurately quantify the radioactivity concentration measured by PET, emission data need to be corrected for photon attenuation; however, MRI signal cannot easily converted into attenuation values, making correction (AC) in PET/MRI challenging. In order further improve current vendor-implemented MR-AC methods absolute quantification, a number of prototype have been proposed literature. These can categorized three types: template/atlas-based, segmentation-based, and reconstruction-based....
The aim of the present study was to examine whether neural structures subserving meditation can be reproducibly measured, and, if so, they are different from those supporting resting state normal consciousness. Cerebral blood flow distribution investigated with 15O-H20 PET technique in nine young adults, who were highly experienced yoga teachers, during relaxation (Yoga Nidra), and In addition, global CBF measured two subjects. Spectral EEG analysis performed throughout investigations....
URBAN, J. P. G.; HOLM, S.; MAROUDAS, A.; NACHEMSON, A.Editor(s): AKESON, WAYNE H. M.D.; MURPHY, ROBERT W. M.D. Author Information
Global cerebral blood flow (CBF), global metabolic rates for oxygen (CMRO 2 ), and glucose (CMR glc lactate efflux were measured during rest activation induced by the Wisconsin card sorting test. Measurements performed in healthy volunteers using Kety–Schmidt technique. CMRO was unchanged activation, whereas CBF CMR both increased 12%, reducing molar ratio of to consumption from 6.0 baseline conditions 5.4 activation. Data obtained period following showed that activation-induced resetting...
It could be expected that the various stages of sleep were reflected in variation overall level cerebral activity and thereby magnitude metabolic rate oxygen (CMRO2) blood flow (CBF). The elusive nature imposes major methodological restrictions on examination this question. We have now measured CBF CMRO2 young healthy volunteers using Kety-Schmidt technique with 133Xe as inert gas. Measurements performed during wakefulness, deep (stage 3/4), rapid-eye-movement (REM) verified by standard...
Combined PET/MR systems have now become available for clinical use. Given the lack of integrated standard transmission (TX) sources in these systems, attenuation and scatter correction (AC) must be performed using MR-images. Since bone tissue cannot easily accounted during MR-AC, PET quantification can biased, particular, vicinity skull. Here, we assess imaging patients phantoms patient data.Nineteen referred to our clinic a PET/CT exam as part diagnostic evaluation suspected dementia were...
By comparing results obtained in vivo on penetration of (35S) sulphate and (3H) methyl glucose into the intervertebral disc adult dogs, with those calculated using Fick's law, diffusion partition coefficients vitro, was shown to be main mechanism for transport o f small solutes disc. About 40 percent endplate area found permeable solutes. However amount solute entering via less negatively charged such as ion, than neutral glucose, because charge exclusion region nucleus. The mean turnover...
The use of positron emitter–labeled compounds for somatostatin receptor imaging (SRI) has become attractive because the prospect improved spatial resolution, accelerated procedures, and ability to quantify tissue radioactivity concentrations. This paper provides results from first-in-humans <sup>64</sup>Cu-DOTATATE, an avidly binding ligand linked a radioisotope with intermediate half-life favorable energy (half-life, 12.7 h; maximum energy, 0.653 MeV). <b>Methods:</b> In prospective setup,...
1. The intramuscular oxygen partial pressure (pO2) in human gastrocnemius muscle was monitored during exercise and compared with metabolite concentrations reflecting the energy redox state tissue. Ten normal subjects ten patients peripheral vascular occlusive disease were investigated. 2. In pO2 at end of related to intensity exercise, expressed as effect (J/s) per contraction. 3. both subject [ATP]/[ADP] ratio, [lactate/[pyruvate] ratio phosphocreatine concentration tissue rest exercise. 4....
The reconstruction of PET brain data in a PET/MR hybrid scanner is challenging the absence transmission sources, where MR images are used for MR-based attenuation correction (MR-AC). main challenge MR-AC to separate bone and air, as neither have signal traditional images, assign correct linear coefficient bone. ultra-short echo time (UTE) sequence was proposed basis this shows small purpose study develop new clinically feasible method with patient specific continuous-valued coefficients that...
A first-in-human clinical trial with Positron Emission Tomography (PET) imaging of the urokinase-type plasminogen activator receptor (uPAR) in patients breast, prostate and bladder cancer, is described. uPAR expressed many types human cancers expression predictive invasion, metastasis indicates poor prognosis. PET therefore holds promise to be a new innovative method for improved cancer diagnosis, staging individual risk stratification. The specific peptide AE105 was conjugated macrocyclic...
Abstract The numbers of diagnostic and therapeutic nuclear medicine agents under investigation are rapidly increasing. Both novel emitters carrier molecules require careful selection measurement procedures. This document provides guidance relevant to dosimetry for first-in human early phase clinical trials such agents. guideline includes a short introduction different molecules, followed by recommendations on the methods activity measurement, pharmacokinetic analyses, as well absorbed dose...
Using repeated positron emission tomography (PET) measures of regional cerebral counts, we investigated the cortical activations induced in eight normal subjects performing different frequencies fingertapping (0.5-4 Hz) with right index finger. The task was auditorially cued and performance recorded during scanning procedure. Performance evaluation showed increased error rates, fingertapping, high low frequencies, best tapping measured midrange frequencies. Significantly activated areas (p <...
Owing to the coupling between CBF and neuronal activity, regional is a reflection of neural activity in different brain regions. In this study we measured during polysomnographically well-defined rapid-eye-movement (REM) sleep by use single photon emission computerized tomography new tracer 99mTc-dl-hexamethylpropyleneamine. Eleven healthy volunteers aged 22 27 years were studied. was on separate nights REM EEG-verified wakefulness. On awakening from sleep, all subjects reported visual...
The effect of hyperinsulinemia on glucose blood-brain barrier (BBB) transport and cerebral metabolism (CMRglc) was studied using the intravenous double-indicator method positron emission tomography [18F]fluorodeoxyglucose as tracer (PET-FDG). Sixteen normal healthy control subjects (25 +/- 4 years old) were twice during a euglycemic euglycemic-hyperinsulinemic condition. Our hypothesis that high physiologic levels insulin did not affect BBB or net glucose. During infusion, arterial plasma...
Results obtained by the 133Xe clearance method with external detectors and transcranial Doppler sonography (TCD) suggest that dynamic exercise causes an increase of global average cerebral blood flow (CBF). These data are contradicted earlier during less-well-defined conditions. To investigate this controversy, we applied Kety-Schmidt technique to measure levels CBF metabolic rate oxygen (CMRO2) rest exercise. Simultaneously determination CMRO2, used TCD determine mean maximal velocity in...
<b><i>Objective:</i></b> To study the association between cortical cerebral metabolic rate of glucose (CMRglc), MRI T2-weighted total lesion area (TLA), cognitive dysfunction, and neurologic disability in MS. <b><i>Background:</i></b> load is widely used clinical evaluation MS patient but little known about associated changes activation. <b><i>Methods:</i></b> Twenty-three patients with clinically definite underwent measurements CMRglc, TLA, motor evoked potentials (MEPs), disability. CMRglc...