Arterial Spin Labeling Magnetic Resonance Imaging for Acute Disorders of Consciousness in the Intensive Care Unit.

Background: To investigate patients with disorders of consciousness (DoC) for residual awareness, guidelines recommend quantifying glucose brain metabolism using positron emission tomography. However, this is not feasible in the intensive care unit (ICU). Cerebral blood flow (CBF) assessed by arterial spin labeling magnetic resonance imaging (ASL-MRI) could serve as a proxy for brain metabolism and reflect consciousness levels in acute DoC.

Ictal and interictal SPECT with Tc-HMPAO in presurgical epilepsy. II: Methodological considerations on hyper- and hypoperfusion.

Objective: Single-photon emission computed tomography (SPECT) with the tracer Tc-HMPAO is a method to visualize the cerebral hyperperfusion during an epileptic seizure and thus localize the epileptogenic zone and seizure propagation. Subtraction of interictal from Ictal SPECT Co-registered to MRI (SISCOM) visualizes areas with relative increases in cerebral blood flow. The purpose of this retrospective study is to explore the added value of visualizing areas of hypoperfusion as well as hyperperfusion, so-called reversed SISCOM.

Ictal and interictal SPECT with Tc-HMPAO in presurgical epilepsy. I: Predictive value and methodological considerations.

Objective: This retrospective study investigates the predictive value of ictal subtraction single-photon emission computed tomography (SPECT) co-registered to magnetic resonance imaging (MRI) (SISCOM) for successful epilepsy surgery.

Methods: 57 patients examined with SISCOM as a part of epilepsy surgery evaluation were divided into two groups based on seizure duration after tracer injection (group 1: Seizure duration above or equal to 30 s, group 2: Seizure duration under 30 s). SISCOM was compared to the surgical site and categorized as good or poor concordance.

Exenatide once weekly for alcohol use disorder investigated in a randomized, placebo-controlled clinical trial.

BackgroundAlcohol use disorder (AUD) is a chronic, relapsing brain disorder that accounts for 5% of deaths annually, and there is an urgent need to develop new targets for therapeutic intervention. The glucagon-like peptide-1 (GLP-1) receptor agonist exenatide reduces alcohol consumption in rodents and nonhuman primates, but its efficacy in patients with AUD is unknown.MethodsIn a randomized, double-blinded, placebo-controlled clinical trial, treatment-seeking AUD patients were assigned to receive exenatide (2 mg subcutaneously) or placebo once weekly for 26 weeks, in addition to standard cognitive-behavioral therapy.

Does glucagon-like peptide-1 (GLP-1) receptor agonist stimulation reduce alcohol intake in patients with alcohol dependence: study protocol of a randomised, double-blinded, placebo-controlled clinical trial.

Introduction: Alcohol dependence is a major public health problem. It is underdiagnosed and undertreated. Even when treated, more than 2/3 of patients in abstinence-oriented treatment will relapse within the first year.

The Variability of Translocator Protein Signal in Brain and Blood of Genotyped Healthy Humans Using In Vivo I-CLINDE SPECT Imaging: A Test-Retest Study.

I-CLINDE is a radiotracer developed for SPECT and targets the 18-kDa translocator protein (TSPO). TSPO is upregulated in glial cells and used as a measure of neuroinflammation in a variety of central nervous system diseases. The aim of this study was to examine the test-retest variability of I-CLINDE binding in healthy subjects.

TSPO Imaging in Glioblastoma Multiforme: A Direct Comparison Between 123I-CLINDE SPECT, 18F-FET PET, and Gadolinium-Enhanced MR Imaging.

Unlabelled: Here we compare translocator protein (TSPO) imaging using 6-chloro-2-(4'-(123)I-iodophenyl)-3-(N,N-diethyl)-imidazo[1,2-a]pyridine-3-acetamide SPECT ((123)I-CLINDE) and amino acid transport imaging using O-(2-(18)F-fluoroethyl)-l-tyrosine PET ((18)F-FET) and investigate whether (123)I-CLINDE is superior to (18)F-FET in predicting progression of glioblastoma multiforme (GBM) at follow-up.

Methods: Three patients with World Health Organization grade IV GBM were scanned with (123)I-CLINDE SPECT, (18)F-FET PET, and gadolinium-enhanced MR imaging. Molecular imaging data were compared with follow-up gadolinium-enhanced MR images or contrast-enhanced CT scans.

The effect of storage conditions on salivary cortisol concentrations using an enzyme immunoassay.

Saliva samples are easy to collect and are applicable for home-sampling, e.g. when studying HPA-axis dynamics to characterize diurnal cortisol profiles and the cortisol awakening response.

In vivo quantification of cerebral translocator protein binding in humans using 6-chloro-2-(4'-123I-iodophenyl)-3-(N,N-diethyl)-imidazo[1,2-a]pyridine-3-acetamide SPECT.

Unlabelled: This study provides the first comprehensive quantification of translocator protein (TSPO) binding using SPECT and 6-chloro-2-(4'-(123)I-iodophenyl)-3-(N,N-diethyl)-imidazo[1,2-a]pyridine-3-acetamide ((123)I-CLINDE) in neurologic patients. (123)I-CLINDE is structurally related to well-known PET ligands such as (18)F-PBR111 and (18)F-DPA-714.

Methods: Six patients with cerebral stroke and 4 patients with glioblastoma multiforme (GBM) underwent 150-min dynamic SPECT scans with arterial blood sampling.

No difference in striatal dopamine transporter availability between active smokers, ex-smokers and non-smokers using [123I]FP-CIT (DaTSCAN) and SPECT.

Background: Mesolimbic and nigrostriatal dopaminergic pathways play important roles in both the rewarding and conditioning effects of drugs. The dopamine transporter (DAT) is of central importance in regulating dopaminergic neurotransmission and in particular in activating the striatal D2-like receptors. Molecular imaging studies of the relationship between DAT availability/dopamine synthesis capacity and active cigarette smoking have shown conflicting results.

Striatal dopamine transporter binding does not correlate with clinical severity in dementia with Lewy bodies.

Unlabelled: Patients who have dementia with Lewy bodies (DLB) show both clinical and histopathologic overlap with Alzheimer disease patients and Parkinson disease patients. In this study, we correlated the core features of DLB (dementia, parkinsonism, hallucinations, and fluctuations) with striatal dopamine transporter (DAT) availability as assessed with SPECT and (123)I-N-(3-iodoprop-2E-enyl)-2-β-carbomethoxy-3β-(4-methylphenyl) nortropane ((123)I-PE2I) in patients with newly diagnosed DLB.

Methods: Two hundred eighty-eight patients were consecutively included in the study as they were referred for diagnostic SPECT scanning of DAT with (123)I-PE2I.

Value of semiquantitative analysis for clinical reporting of 123I-2-β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl)nortropane SPECT studies.

Unlabelled: Clinical (123)I-2-β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl)nortropane ((123)I-FP-CIT) SPECT studies are commonly performed and reported using visual evaluation of tracer binding, an inherently subjective method. Increased objectivity can potentially be obtained using semiquantitative analysis. In this study, we assessed whether semiquantitative analysis of (123)I-FP-CIT tracer binding created more reproducible clinical reporting.

Predictive value of dopamine transporter SPECT imaging with [¹²³I]PE2I in patients with subtle parkinsonian symptoms.

Purpose: To examine the diagnostic sensitivity and specificity of dopamine transporter SPECT imaging with a highly dopamine transporter selective radioligand. The study included consecutively enrolled, drug-naive patients with an average short history of parkinsonian motor symptoms, referred for diagnostic scanning.

Methods: The study group comprised 288 patients naive to antiparkinson treatment who were enrolled as they were admitted for a diagnostic SPECT scan with the radioligand [(123)I]-N-(3-iodoprop-2E-enyl)-2-β-carbomethoxy-3β-(4-methylphenyl)nortropane ((123)I-PE2I).

Validation of a method for accurate and highly reproducible quantification of brain dopamine transporter SPECT studies.

Unlabelled: In nuclear medicine brain imaging, it is important to delineate regions of interest (ROIs) so that the outcome is both accurate and reproducible. The purpose of this study was to validate a new time-saving algorithm (DATquan) for accurate and reproducible quantification of the striatal dopamine transporter (DAT) with appropriate radioligands and SPECT and without the need for structural brain scanning.

Methods: In a reconstructed DAT SPECT image, DATquan automatically calculated the ratio at steady state of specifically bound radioligand to nondisplaceable radioligand in tissue (BP(ND)) within striatal ROIs that were delineated by use of a semiautomatic template-based alignment approach.

Striatal dopamine transporter binding correlates with serum BDNF levels in patients with striatal dopaminergic neurodegeneration.

Compelling evidence has shown, that neurotrophins responsible for the regulation of neuronal growth, survival, and differentiation are involved in neurodegenerative diseases. Whereas lower serum levels of brain derived neurotrophic factor (BDNF) have been observed in patients with Parkinson's disease, no studies have directly related the degree of striatal neurodegeneration of dopaminergic neurons (DA) with serum BDNF levels. In this study we examined the relationship between striatal neurodegeneration as determined with (123)I-PE2I-single photon emission computer tomography (SPECT) and serum BDNF levels in patients with parkinsonism.

Experimental determination of the weighting factor for the energy window subtraction-based downscatter correction for I-123 in brain SPECT studies.

Correction for downscatter in I-123 SPECT can be performed by the subtraction of a secondary energy window from the main window, as in the triple-energy window method. This is potentially noise sensitive. For studies with limited amount of counts (e.

Serotonin transporters in dopamine transporter imaging: a head-to-head comparison of dopamine transporter SPECT radioligands 123I-FP-CIT and 123I-PE2I.

Unlabelled: Current SPECT radioligands available for in vivo imaging of the dopamine transporter (DAT) also show affinity for monoamine transporters other than DAT, especially the serotonin transporter (SERT). The effect of this lack of selectivity for in vivo imaging is unknown. In this study, we compared the SPECT radioligands (123)I-2-β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl)nortropane ((123)I-FP-CIT) and (123)I-N-(3-iodoprop-2E-enyl)-2-β-carbomethoxy-3β-(4-methylphenyl) nortropane ((123)I-PE2I), which has a 10-fold higher selectivity than (123)I-FP-CIT for DAT versus SERT [corrected].

MRI-guided region-of-interest delineation is comparable to manual delineation in dopamine transporter SPECT quantification in patients: a reproducibility study.

Unlabelled: A particularly sensitive step in the quantification of SPECT images of the dopamine transporter (DAT) is a correct delineation of the region of interest (ROI). In this study, we primarily compared the reproducibility of the following different approaches for ROI delineation in SPECT images of the DAT: the use of manual delineation (MD) on high-count striatal slides directly on the SPECT image, ROI delineation based on individual MR images (MRD), and oversized striatal ROIs-that is, the striatal volume of interest (SVI), as described previously. We also assessed the ability of the different approaches to identify striatal pathology in patients with parkinsonism.

Required time delay from 99mTc-HMPAO injection to SPECT data acquisition: healthy subjects and patients with rCBF pattern.

Purpose: Functional brain (99m)Tc-HMPAO single-photon emission computed tomography (SPECT) is a useful diagnostic tool for assessment of regional cerebral blood flow, particularly in dementia, cerebrovascular disease and epilepsy. Currently, the European and American Association of Nuclear Medicine Procedure Guidelines for Brain Perfusion SPET using (99m)Tc-labeled Radiopharmaceuticals recommend a time delay of 90 min between injection of (99m)Tc-HMPAO and data acquisition. This time delay is difficult to comply within the daily routine and present a problem, particularly with the elderly or demented patients.

Reproducibility of [123I]PE2I binding to dopamine transporters with SPECT.

Purpose: The iodinated cocaine derivative [(123)I]PE2I is a new selective ligand for in vivo studies of the dopamine transporter (DAT) with SPECT. Recently, a bolus/infusion (B/I) protocol for [(123)I]PE2I measurements of DAT density was established [Pinborg LH et al. J Nucl Med 2005;46:1119-271].