There is growing evidence of activated microglia and inflammatory processes in the cerebral cortex in amyotrophic lateral sclerosis (ALS). Activated microglia is characterized by increased expression of the 18 kDa translocator protein (TSPO) in the brain and may be a useful biomarker of inflammation. In this study, we evaluated neuroinflammation in ALS patients using a radioligand of TSPO, (18)F-DPA-714.
View Article and Find Full Text PDFThe prognosis for testicular cancer is excellent, with a 5-year survival rate greater than 95%. Patients affected can therefore expect to be cured after treatment. Successful treatment requires assessment of the condition at the various stages of its management.
View Article and Find Full Text PDFIntroduction: The translocator protein 18 kDa (TSPO), although minimally expressed in healthy brain, is up-regulated in pathological conditions, coinciding with microglial activation. It is thereby a suitable in vivo biomarker of neuroinflammation for detection, evaluation and therapeutic monitoring of brain diseases. We aimed to estimate the radiation dosimetry of the positron emission tomography (PET) TSPO radioligand [(18)F]DPA-714, and we evaluated in healthy volunteers its whole-body uptake and cerebral kinetics.
View Article and Find Full Text PDFPurpose: Partial volume effects (PVEs) are consequences of the limited spatial resolution in emission tomography leading to underestimation of uptake in tissues of size similar to the point spread function (PSF) of the scanner as well as activity spillover between adjacent structures. Among PVE correction methodologies, a voxel-wise mutual multiresolution analysis (MMA) was recently introduced. MMA is based on the extraction and transformation of high resolution details from an anatomical image (MR/CT) and their subsequent incorporation into a low-resolution PET image using wavelet decompositions.
View Article and Find Full Text PDFA short historical survey recalls the main techniques of medical imaging, based on modern physico-chemistry and computer science. Imagery has provided novel visions of the inside of the body, which are not self-obvious but require a training of the gaze. Yet, these new images have permeated the contemporary mind and inspired esthetic ventures.
View Article and Find Full Text PDFLymphoscintigraphy is based upon the physiological transport of small radioactive particles injected into interstitium toward lymphatic vessels and nodes. Lymphoscintigraphy directly investigates lymphatic system while other methods (ultrasounds, CT, MRI) investigate tissular consequences of lymphatic disease. The scintigraphic procedure has to be standardized in order to be reproducible.
View Article and Find Full Text PDFPurpose: Metastatic carcinoid is an incurable malignancy whose symptoms, such as diarrhea and flushing, can be debilitating and occasionally life-threatening. Although symptom relief is available with octreotide, the disease eventually becomes refractory to octreotide, leaving no proven treatment options. The goal of this study was to evaluate the clinical effect of using (90)Y-edotreotide to treat symptomatic patients with carcinoid tumors.
View Article and Find Full Text PDFThis study was designed to select a suitable solid bolus for esophageal scintigraphy. Optimally, a bolus should leave minimal residual buccal and pharyngeal activity after being swallowed. We compared the oropharyngeal behavior of three boluses, i.
View Article and Find Full Text PDFObjectives: The objectives of this work were a) to assess the feasibility of lymphoscintigraphy in very young children, and b) to assess its usefulness in understanding the underlying pathophysiology.
Patients And Methods: Forty-one children (age range 3 months-16 years) with primary lymphedema of the lower and/or upper limbs underwent lymphosinctigraphy using 99mTC-labeled colloid (Nanocis or Nanocol) injected subcutaneous at the foot and/or hand level. Recording time, which depended on the child's age, included at least static images during the thirty minutes following injection and four hours later.
Presymptomatic diagnosis of the loss of nigrostriatal neurons that characterises Parkinson's disease, is a crucial issue for future neuroprotective therapies as degeneration exceeds 70 to 80% when symptoms appear. Here we propose an early diagnosis method that utilises single photon emission computerized tomography (SPECT) coupled to the iodine-123-labelled selective dopamine transporter ligand N-(3-ioprop-2E-enyl)-2-beta-(4-methylphenyl)nortropane ((123)I-PE2I), applying Logan's graphical method for quantification. Sequential (123)I-PE2I SPECT acquisitions were performed in nonhuman primates chronically treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine according to a regimen that consistently produces a progressive Parkinsonian state.
View Article and Find Full Text PDFUnlabelled: (E)-N-(3-iodoprop-2-enyl)-2beta-carbomethoxy-3beta-(4'-methyl-phenyl) nortropane (PE2I), a cocaine analog, is a new, highly specific tracer for imaging dopamine transporter labeled with (123)I for in vivo SPECT. Its reversible binding on dopamine transporter and its rapid kinetics allow quantification of its binding potential according to a 3-compartment model. For quantification of distribution volume of reversible tracer, Logan developed a noninvasive and graphical method that allows accurate estimation of binding potential.
View Article and Find Full Text PDFNucl Med Commun
December 2001
The aim of this prospective study was to determine whether anti-carcinoembryonic antigen (anti-CEA) scintigraphy is a useful additional technique in the diagnosis recurrence of colorectal cancer. Forty patients with suspected recurrence of colorectal cancer, underwent immunoscintigraphy (IS) and helical computed tomography (CT) in the 2 weeks before surgery. Surgical findings were used to evaluate the performance of the imaging techniques.
View Article and Find Full Text PDF123I-Iodolisuride has high specific affinity for binding on dopamine D2 receptors in the striatum and has been used in a few single photon emission computed tomography (SPECT) studies of extrapyramidal disorders. The diagnosis of Parkinson's disease (PD) is very difficult in the first 5 years of evolution, with 15-25% false positive diagnoses. The aim of this study was therefore to determine the value of iodolisuride SPECT in discriminating Parkinson's from the most frequent Parkinson-plus syndromes (PPS).
View Article and Find Full Text PDFBackground: The interpretation of 99mTc diethylenetriamine pentaacetate (99mTc DTPA) aerosol clearance is based on the hypothesis that the 99mTc-DTPA complex is not altered by the nebulization process.
Objectives: To characterize (1) the radiochemical purity (RCP) of 99mTc-DTPA and the stability of labeling after jet nebulization, and (2) the particle size distribution of the aerosol.
Methods: RCP and stability--the aerosol was driven by oxygen, captured on filters which were eluted and RCP was checked by thin layer chromatography.
The aim of this study was to assess the prognostic value of early brain scintigraphy in head injury in relation to long-term neuropsychological behavior. Twenty-four patients underwent technetium-99m (Tc-99m) ethyl cysteinate dimer single photon emission computed tomography (SPECT) within 1 month of the trauma. Scintigraphic abnormalities were evaluated both visually and semiquantitatively using the brain-to-cerebellum ratio method.
View Article and Find Full Text PDFDosimetry and therapeutic application of [(131)I]-Tyr3-octreotide were evaluated in three patients with metastatic paraganglioma and carcinoid tumor. The in vitro stability of [(131)I]-Tyr3-octreotide was verified. Tumor uptake and residence time were between 0.
View Article and Find Full Text PDFPurpose: Hypoxic-ischemic injury induces early changes in cerebral energy that later lead to the presence and extension of brain damage and subsequently to severe neurodevelopmental impairments such as the dyskinetic form of cerebral palsy, which is associated with damage to the striatum. The purpose of the current study was to evaluate the viability of D2 receptors in the perinatal period using I-123 iodobenzamide brain SPECT and to correlate this with early neurologic status.
Methods: After obtaining informed parental consent, 12 full-term neonates with hypoxic-ischemic events were included.
Background: Cognitive disorders have been described in amyotrophic lateral sclerosis, but usually after the diagnosis has ben established.
Case Report: A 57-year-old man was intubated for acute respiratory distress subsequent to pneumonia and diaphragm palsy. He had a 2-year history of drug-resistant depression and deterioration of cognitive functions.
Eletriptan (Relpax) is a novel 5-hydroxytryptamine (serotonin)(1D/1B) agonist currently in development for the acute treatment of migraine. The aim of this work was to evaluate the relative induction potency of eletriptan in vitro compared with well characterized cytochrome P-450 (CYP) inducers with primary cultures of human hepatocytes and to relate this to the situation in vivo. Eletriptan was a weak inducer of CYP3A4 protein and cyclosporin A oxidation in four of the six cultures used, whereas rifampicin was a potent inducer in all cultures.
View Article and Find Full Text PDFVarious parameters are currently used for the semi-quantitative assessment of dopamine D2 receptors and differ according to the delineation of the striatal region of interest (ROI) and the choice of the reference ROI. The aim of this study was to assess the value of different ROI approaches in differentiating patients with normal or increased numbers of D2 dopamine receptors (group 1 = Parkinson's disease, n = 8) from patients with decreased dopamine D2 receptors (group 2 = other extrapyramidal syndromes, n = 9) using 123I-iodolisuride SPET (ILIS-SPET). 123I-iodolisuride (190 +/- 31 MBq) and 99Tcm-ethyl cysteinate dimer (99Tcm-ECD) perfusion SPET were performed in the same position, with a dual-headed gamera camera equipped with fan beam collimators.
View Article and Find Full Text PDFScintigraphic imagery is a functional image based on the difference of the in vivo concentration of injected radio-active traces as a function-of the metabolic characteristics of the tissues. A positive emission tomography (TEP) relies on an injection of substances which reflect the metabolic activity of the tissues and consist of protein renewal with 11C-methionine or glucose metabolism with F18-fluorodeoxyglucose (FTG). The imagery by TEP enables 85-90% of solitary pulmonary nodules to be detected.
View Article and Find Full Text PDFFor the diagnosis and follow-up of neurodegenerative diseases, many cocaine derivatives have been proposed as radioligands to explore the dopamine transporter. As none of them have all the criteria of specificity and kinetics for human use, we have developed a new derivative, (E)-N-(3-iodoprop-2-enyl)-2beta-carbomethoxy-3beta-(4'-methy lphenyl)nortropane (PE2I), which displays promising properties. We report the characterization of PE2I in vitro on rat striatal membranes and in vivo in rats and in monkeys.
View Article and Find Full Text PDFThe iodine-123 labelled selective ligand N-(3-iodoprop-2E-enyl)-2-beta-carbomethoxy-3beta-(4-methylphenyl) nortropane ([123I]PE2I) was evaluated as a probe for in vivo dopamine transporter imaging in the human brain. Six healthy subjects were imaged with a high-resolution single-photon emission tomography scanner. Striatal radioactivity peaked at 1 h after injection.
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