New functional imaging techniques, including positron emission tomography, transcranial magnetic stimulation and functional magnetic resonance imaging, promise to allow the noninvasive study of haemodynamic, metabolic and activation parameters during acute migraine attacks in humans. These techniques are currently being applied to the study of the transient neurologic symptoms of the ...

In order to perform attenuation correction in emission tomography an attenuation map is required. We propose a new method to compute this map directly from the emission sinogram, eliminating the transmission scan from the acquisition protocol. The problem is formulated as an optimization task where the objective function is a ...

It is difficult to distinguish manganism from idiopathic parkinsonism by clinical signs only. Case history and examination: A 48-year-old welder for over 10 years complained of masked face, right side (arm and leg) resting tremor, and bradykinesia for over one year. Magnetic resonance imaging (MRI) findings showed symmetrical high signal ...

Normal brain tissue is probably the most important tissue compartment in the brain involved in adverse radiation effects (AREs). The capabilities of computerized tomography, magnetic resonance imaging, and positron emission tomography in repeat examinations of a treatment outcome provide a baseline by which to monitor the AREs in vivo and ...

It is well known that exposure to manganese, solvents, or carbon monoxide in an occupational setting may lead to central nervous system damage and parkinsonism. The most important solvents in this respect are methanol, toluene, carbon disulfide, and n-hexane. We describe three patients who had been exposed to various solvents ...

Parkinsonism is a feature of a number of neurodegenerative diseases, including Parkinson's disease, multiple system atrophy and progressive supranuclear palsy. The results of post-mortem studies point to dysfunction of the dopaminergic neurotransmitter system in patients with parkinsonism. Nowadays, by using single-photon emission tomography (SPET) and positron emission tomography (PET) it ...

The role of functional neuroimaging techniques in furthering the understanding of pathophysiological mechanisms of neurological diseases and in the assessment of neurological patients is increasingly important. Here, we review data mainly from emission tomography techniques, namely positron emission tomography (PET) and single photon emission computerized tomography (SPECT), that have helped ...

Gradient-based iterative methods often converge slowly for tomographic image reconstruction and image restoration problems, but can be accelerated by suitable preconditioners. Diagonal preconditioners offer some improvement in convergence rate, but do not incorporate the structure of the Hessian matrices in imaging problems. Circulant preconditioners can provide remarkable acceleration for inverse ...

Positron emission tomography (PET) is now regularly used in the diagnosis and staging of cancer. These uses and its ability to monitor treatment response would be aided by the development of imaging agents that can be used to measure tissue and tumor proliferation. We have developed and tested [F-18]FLT (3'-deoxy-3'-fluorothymidine); ...

In this study, the parameters of notches in the Audioscan have been compared with the distortion product otoacoustic emission (DPOAE) findings in 100 subjects with normal hearing, including 55 normal controls and 45 patients with King Kopetzky syndrome. Of those, 35 subjects had Audioscan notches (11 controls and 24 patients), ...

Acute effects of kanamycin and/or furosemide administration on the stria vascularis of the guinea pig cochlea were assessed by distortion product otoacoustic emission (DPOAE) and transmission electron microscopy. Kanamycin alone failed to affect the DPOAE levels and ultrastructural changes. Furosemide alone caused a rapid but reversible fall of the DPOAE ...

The diagnosis of chronic fatigue syndrome (CFS) is made difficult by the absence of specific biomedical markers, and depends primarily on determining whether subjective information provided by the patient meets the clinical case definition of this syndrome. Reported cognitive difficulties and/or complaints of headache may instigate referral for brain imaging. ...

Yttrium-90 is widely used in radioimmunotherapy but does not emit photons for imaging. Indium-111, a chemically similar atom has been used instead as a tracer for the distribution of 90Y-labeled antibodies. Recent advances in gamma camera technology have made it possible to image at energies higher than 364 keV. This ...

Imaging of monoamine oxidase of subtype B (MAO B) is of interest in various neurological diseases. In the past non-invasive assessment of MAO B has only been possible with positron emission tomography (PET) ligands. Given the limited availability of PET, a single-photon emission tomography (SPET) ligand would be desirable. In ...

Neuroimaging techniques have improved the understanding, diagnosis, and management of epilepsy. By providing excellent structural information, MRI is the technique of choice in evaluating patients with epilepsy. Functional imaging techniques, including MR spectroscopy, functional MRI, positron emission tomography, and single photon emission CT, permit noninvasive assessment of the epileptic substrate, ...

Techniques such as positron-emission tomography, single-photon-emission computed tomography, functional magnetic-resonance imaging and magnetoencephalography permit the observation of biological processes in the brain in a noninvasive manner. They have yielded new insights into the biological interrelations of sensory, motor and cognitive functions, as well as into brain diseases. Combined use of ...

The assessment of head and neck cancer has traditionally involved clinical examination and anatomical imaging by computed tomography (CT) or magnetic resonance imaging (MRI). We present a case where a problem of clinical confusion and inconclusive radiology was resolved by the use of positron emission tomography (PET) coregistered with CT.

Rasmussen encephalitis is a chronic, progressive inflammation of the brain of unknown origin. Early diagnosis and treatment with immunoactive agents and/or hemispherectomy are sought to prevent the progressive cognitive decline that accompanies this disease. Combined anatomic and functional neuroimaging may serve to focus the diagnostic workup and to hasten brain ...

A practical method for scatter and attenuation compensation was employed in thallium-201 myocardial single-photon emission tomography (SPET or ECT) with the triple-energy-window (TEW) technique and an iterative attenuation correction method by using a measured attenuation map. The map was reconstructed from technetium-99m transmission CT (TCT) data. A dual-headed SPET gamma ...

Most of the mitochondrial disorders affect the brain and muscle metabolism with variable degrees of impairment. The diagnostic usefulness of the following physiological and imaging methods, which also offer functional information that can be used for follow-up, is critically assessed: lactate levels, exercise testing, phosphorus magnetic resonance spectroscopy (MRS), proton ...

The purpose of this paper is to review the potential functional and morphological effects of long duration space flight on the human central nervous system (CNS) and how current neuroimaging techniques may be utilized to study these effects. It must be determined if there will be any detrimental changes to ...

PURPOSE: Previous [11C]flumazenil (FMZ) positron emission tomography (PET) investigations in patients with idiopathic generalized epilepsy (IGE) have demonstrated nonsignificant global cortical decreases in central benzodiazepine gamma-aminobutyric acid A (GABA[A]) receptor (cBZR) binding or focal decreases in the thalamus and increases in the cerebellar nuclei with no changes in cerebral cortex. ...

Psychopaths have been described as human predators who use charm, intimidation, and violence to control others and to satisfy their own needs. Underlying their propensity to violate social norms and expectations is a profound lack of empathy, guilt, or remorse, affective processes that have long resisted scientific investigation. Using brain ...

Functional brain imaging studies of memory and attention with positron emission tomography and functional magnetic resonance imaging demonstrate involvement of specific regions of the normal human brain. Possible anatomical substrates for different types of memory have been identified. Different aspects of attention mechanisms, such as modulation of early visual areas, ...

We investigated the effects of varying the injected dose, speed of injection, and scan duration to maximize the sensitivity of noninvasive activation studies with 15O-water and three-dimensional positron emission tomography. A covert word generation task was used in four subjects with bolus injections of 2.5 to 3D mCi of 15O-water. ...

This article describes magnetic source imaging, a newly-developing technology which can be used to noninvasively map eloquent cortex prior to surgical procedures. It is based on large-array detection of extracranial magnetic fields arising from neuronal currents evoked by peripheral stimulation. A range of evoked and spontaneous neuromagnetic activities are discussed ...

Radiolabelled 2beta-carbomethoxy-3beta-(4-iodophenyl)tropane (beta-CIT) has been used in clinical studies for the imaging of dopamine and serotonin transporters with single-photon emission tomography (SPET). 2beta-Carbomethoxy-3beta-(4-iodophenyl)nortropane (nor-beta-CIT) is a des-methyl analogue of beta-CIT, which in vitro has tenfold higher affinity (IC50=0.36 nM) to the serotonin transporter than beta-CIT (IC50=4.2 nM). Nor-beta-CIT may thus ...

BACKGROUND: Photon attenuation is a major cause of artifacts on single-photon emission tomographic imaging. METHODS AND RESULTS: To study a new method to perform photon attenuation correction (AC), we used a cardiac phantom filled with (99m)Tc and imaged it (1) without extrinsic attenuation or defects, (2) with extrinsic attenuation but ...

The iodine-123 labelled ligand benzamide epidepride was evaluated as a probe for in vivo imaging of striatal and extrastriatal dopamine D2 receptor sites in the human brain. Four healthy males were imaged with a high-resolution single-photon emission tomography scanner. Striatal radioactivity peaked at 3 h after injection. The specific binding ...

No-carrier-added [N-methyl-11C]LY257327 was synthesized by methylation of the free base of the desmethyl precursor LY214281 with [11C]methyl iodide in anhydrous acetonitrile. Synthesis time was 52 +/- 3 min, radiochemical yield (based on [11C]methyl iodide) was 35 +/- 8%, radiochemical purity was 99 +/- 1%, and specific activity at EOB was ...

We present the MR and single-photon emission CT findings in a 3-year-old patient in whom Klüver-Bucy syndrome developed after Reye syndrome. MR images showed diffuse brain atrophy, which was predominant in the temporal lobes, and single-photon emission CT scans showed decreased cerebral perfusion in the bilateral temporal lobes and associated ...

99Tcm-dimercaptosuccinic acid (99Tcm-DMSA) planar and single photon emission tomographic images from 100 children were reviewed to analyse whether linear defects corresponding to anatomical characteristics of interrenuncular septum (IRS) could be seen. Thirty sites in 30 kidneys (20 right, 10 left) from 27 patients were determined as showing IRS. They were ...

This retrospective study examined 20 consecutively treated trauma patients who reported a chief complaint of earache or trauma preauricular pain. These individuals were examined with magnetic resonance imaging (MRI), emission study using single photon emission, computerized tomography, and joints auscultation using Doppler sound magnification. There are no statistically significant correlations ...

Hematospermia is a disconcerting symptom that produces extreme anxiety in sexually active male patients. To understand the pathophysiology of hematospermia, the anatomy of the ejaculatory system and neurophysiology of emission and ejaculation is essential. Emission and ejaculation must be present for hematospermia to occur. Hematospermia may be the result of ...

Loss of striatal dopamine (DA) transporters in Parkinson's disease (PD) has been accurately assessed in vivo by single-photon emission tomography (SPET) studies using [123I]beta-CIT. However, these studies have also shown that adequate imaging of the striatal DA transporter content can be performed only 20-30 h following the injection of [123I]beta-CIT, ...

A mathematical model, for which rigorous methods of statistical inference are available, is described and techniques for image enhancement and linear discriminant analysis of groups are developed. Since the gray values of neighboring pixels in tomographically produced medical images are spatially correlated, the calculations are carried out in the Fourier ...

Positron emission tomography, single photon emission computed tomography and magnetic resonance spectroscopy provide distinct, uncorrelated and sensitive indicators of brain tumors which can be used to improve differential diagnosis, biopsy guidance or therapy monitoring. New findings, including conflicting ethyl-cysteinate-dimer/hexamethyl-propyleneamineoxide uptake in single photon emission computed tomography and increased lipids and ...

A capillary electrophoresis (CE) postcolumn radionuclide detector has been developed that uses a commercial phosphor-imaging detector and has been optimized for low-energy beta emitters. Eluant from the separation capillary is deposited on a membrane. Emission from radioactive analytes on the membrane is integrated using the phosphor-imaging system for 10-72 h. ...

This report describes techniques and protocols implemented at the Geneva Canton University Hospitals (HUG) for the combination of various biomedical imaging modalities and sensors including electromagnetic tomography, to study, assess, and localize neurological (dys) function. The interest for this combination stems from the broad variety of information brought out by ...

Targeted radionuclide therapy is becoming an increasingly popular treatment modality as an alternative or as an adjunct to external beam radiotherapy and chemotherapy. The present method of dosimetry based on the MIRD system requires measurements of the concentration of the radionuclide in the target and risk tissues and the effective ...

Neuropsychiatric symptoms are recognized to occur in a significant percentage of systemic lupus erythematosus patients and to be a leading cause of morbidity and morality in lupus. Recent findings regarding the clinical presentation, diagnosis, pathogenesis, and treatment of neuropsychiatric lupus erythematosus are reviewed. The study of neurocognitive deficits and psychosocial ...

This article discusses various legal issues posed when the results of position emission tomographic scans are sought to be introduced in criminal trials.

A woman aged 21 years noticed numbness of the left hand, dysarthria, and right hemiparesis. Magnetic resonance imaging (MRI) showed homogeneously enhanced lesions in the bilateral cerebral white matter; these enlarged within 2 weeks, showing ring-like enhancement, and then spontaneously decreased in size and enhancement. Neurocysticercosis was confirmed by repeated, ...

We report the case of a child with drug-refractory partial epilepsy in whom computed tomography showed no abnormality and magnetic resonance imaging showed a noninvasive cystic lesion in the left hippocampus. The finding in the positron emission tomography study with L-[methyl-11C]-methionine as a tracer suggested a tumor. This finding was ...

An increasing number of patients are presenting with central nervous system complications of human immunodeficiency virus infection. New imaging technologies such as magnetic resonance imaging, magnetic resonance proton spectroscopy, single-photon emission computed tomography, and positron emission tomography are playing an ever-increasing role in the diagnosis of these complications. As therapeutic ...

As an equivalent source localisation technique, the radial dipole source has been chosen as the equivalent source of the actual neural source in the recently developed cortical imaging technique (CIT). In this short paper, the point current source is numerically tested as a new kind of equivalent source for implementing ...

Dopamine (DA) deficiency has been implicated in Lesch-Nyhan disease (LND), a genetic disorder that is characterized by hyperuricemia, choreoathetosis, dystonia, and compulsive self-injury. To establish that DA deficiency is present in LND, the ligand WIN-35,428, which binds to DA transporters, was used to estimate the density of DA-containing neurons in ...

Neuroimaging in anorexia nervosa has revealed morphological and functional alterations, most of which are currently interpreted as consequences of the anorectic state that are reversible, at least partially, after weight gain. Enlargement of CSF spaces, mainly of cortical sulci, is evident on CT and MRI. This reversible shrinkage of brain ...

Debris in the ear canal and ear canal collapse in newborns have been shown to interfere with recording transient evoked otoacoustic emissions (TEOAEs). The purpose of this study was to prospectively evaluate the effects of two simple ear canal cleaning procedures on the TEOAE responses of normal newborns. Three hundred ...

In a patient with the occipitoparietal form of Creutzfeldt-Jakob disease (CJD) (Heidenhain type) positron emission tomography (PET) demonstrated decreased glucose utilization in the occipital lobes and adjacent cortical regions. Single photon emission computed tomography (SPECT) with 99mTc-bicisate showed a "coupled" decrease in blood flow in identical cortical areas in this ...