Evaluation of High-Sensitivity Organ-Specific Positron Emission Tomography (PET) System

The partial pressure in oxygen remains challenging to map in the brain. Two main strategies exist to obtain surrogate measures of tissue oxygenation: the tissue saturation studied by magnetic resonance imaging (StO2-MRI) and the identification of hypoxia by a positron emission tomography (PET) biomarker with 3-[18F]fluoro-1-(2-nitro-1-imidazolyl)-2-propanol ([18F]-FMISO) as the leading radiopharmaceutical. Nonetheless, a formal validation of StO2-MRI against FMISO-PET has not been performed. The objective of our studies was to compare the two approaches in (a) the normal rat brain when the rats were submitted to hypoxemia; (b) animals implanted with four tumour types differentiated by their oxygenation. Rats were submitted to normoxic and hypoxemic conditions. For the brain tumour experiments, U87-MG, U251-MG, 9L and C6 glioma cells were orthotopically inoculated in rats. For both experiments, StO2-MRI and [18F]-FMISO PET were performed sequentially. Under hypoxemia conditions, StO2-MRI revealed a decrease in oxygen saturation in the brain. Nonetheless, [18F]-FMISO PET, pimonidazole immunohistochemistry and molecular biology were insensitive to hypoxia. Within the context of tumours, StO2-MRI was able to detect hypoxia in the hypoxic models, mimicking [18F]-FMISO PET with high sensitivity/specificity. Altogether, our data clearly support that, in brain pathologies, StO2-MRI could be a robust and specific imaging biomarker to assess hypoxia.

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[11C]-Methionine Positron Emission Tomography in the Postoperative Imaging and Followup of Patients with Primary and Recurrent Gliomas

ISRN Oncology ◽

10.1155/2014/463152 ◽

2014 ◽

Vol 2014 ◽

pp. 1-6 ◽

Cited By ~ 3

Author(s):

Matteo Santoni ◽

Cristina Nanni ◽

Alessandro Bittoni ◽

Gabriele Polonara ◽

Alessandro Paccapelo ◽

...

Keyword(s):

Positron Emission Tomography ◽

Residual Disease ◽

Karnofsky Performance Status ◽

Performance Status ◽

High Sensitivity ◽

Emission Tomography ◽

Low Grade ◽

Postoperative Imaging ◽

Positron Emission ◽

Met Pet

We investigated the sensitivity and specificity of [11C]-methionine positron emission tomography ([11C]-MET PET) in the management of glioma patients. We retrospectively analysed data from 53 patients with primary gliomas (16 low grade astrocytomas, 15 anaplastic astrocytomas and 22 glioblastomas) and Karnofsky Performance Status (KPS) > 70. Patients underwent [11C]-MET PET scans (N=249) and parallel contrast-enhanced MRI (N=193) and/or CT (N=113) controls. In low grade glioma patients, MRI or CT findings associated with [11C]-MET PET additional data allowed discrimination residual disease from postsurgical changes in 96.22% of these cases. [11C]-MET PET early allowed detection of malignant progression from low grade to anaplastic astrocytoma with high sensitivity (91.56%) and specificity (95.18%). In anaplastic astrocytomas, we registered high sensitivity (93.97%) and specificity (95.18%) in the postoperative imaging and during the followup of these patients. In GBM patients, CT and/or MRI scans with additional [11C]-MET PET data registered a sensitivity of 96.92% in the postsurgical evaluation and in the tumour assessment during temozolomide therapy. A significant correlation was found between [11C]-MET mean uptake index and histologic grading (P<0.001). These findings support the notion that complementary information derived from [11C]-MET PET may be helpful in postoperative and successive tumor assessment of glioma patients.

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Geoscientific process monitoring with positron emission tomography (GeoPET)

10.5194/se-2016-35 ◽

2016 ◽

Cited By ~ 1

Author(s):

Johannes Kulenkampff ◽

Marion Gründig ◽

Abdelhamid Zakhnini ◽

Johanna Lippmann-Pipke

Keyword(s):

Positron Emission Tomography ◽

Process Monitoring ◽

Diffusion Processes ◽

Matrix Effects ◽

High Sensitivity ◽

Transport Processes ◽

Emission Tomography ◽

Experimental Conditions ◽

Positron Emission ◽

The Impact

Abstract. Transport processes in geomaterials can be observed with input-output experiments, which yield no direct information on the impact of heterogeneities, or they can be assessed by model simulations based on structural imaging with µCT. Positron emission tomography (PET) provides an alternative experimental observation method which directly and quantitatively yields the spatiotemporal distribution of tracer concentration. Process observation with PET benefits from its extremely high sensitivity together with a resolution that is acceptable in relation to standard drill core sizes. We strongly recommend applying high-resolution PET scanners in order to achieve a resolution in the order of 1 mm. We discuss the particularities of PET applications in geoscientific experiments (GeoPET), which essentially are due to high material density. Although PET is rather insensitive to matrix effects, mass attenuation and Compton scattering have to be corrected thoroughly in order to derive quantitative values. Examples of process monitoring of advection and diffusion processes with GeoPET are illustrating the procedure and the experimental conditions, as well as the benefits and limits of the method.

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High-Sensitivity Permeation Analysis of Ultrasmall Nanoparticles Across the Skin by Positron Emission Tomography

Bioconjugate Chemistry ◽

10.1021/acs.bioconjchem.1c00017 ◽

2021 ◽

Vol 32 (4) ◽

pp. 729-745

Author(s):

Mahmoud M. Omar ◽

Myriam Laprise-Pelletier ◽

Pascale Chevallier ◽

Ludovic Tuduri ◽

Marc-André Fortin

Keyword(s):

Positron Emission Tomography ◽

High Sensitivity ◽

Emission Tomography ◽

Positron Emission ◽

Ultrasmall Nanoparticles

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Use of a medical positron emission tomography cyclotron to perform proton-induced X-ray emission analysis

International Journal of PIXE ◽

10.1142/s0129083518500183 ◽

2018 ◽

Vol 28 (03n04) ◽

pp. 93-100

Author(s):

Keizo Ishii ◽

Atsuki Terakawa ◽

Hiroki Ushijima ◽

Keitaro Hitomi ◽

Nobumichi Nagano ◽

...

Keyword(s):

Positron Emission Tomography ◽

High Sensitivity ◽

Beam Current ◽

Ion Source ◽

Emission Tomography ◽

Emission Analysis ◽

Pixe Analysis ◽

Proton Beams ◽

X Ray ◽

Positron Emission

We explored whether medical positron emission tomography (PET) cyclotron proton beams could be used for proton-induced X-ray emission (PIXE) analysis. The beam current of the medical PET cyclotron is high, as required for radioisotope production, and is not commonly used for PIXE analysis. We successfully extracted stable proton beams of low intensity by using the ion source of a medical cyclotron to exploit proton impurities in deuteron gas. We performed 20-MeV PIXE analysis of a biological sample (used tea leaves). Elements lighter than Sr could be detected with high sensitivity ([Formula: see text]14 ppm) using a silicon drift detector. We thus showed that a medical cyclotron widely used for PET diagnosis could be employed for PIXE analysis of biological samples.

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Abnormalities at three musculoskeletal sites on whole-body positron emission tomography/computed tomography can diagnose polymyalgia rheumatica with high sensitivity and specificity

European Journal of Nuclear Medicine and Molecular Imaging ◽

10.1007/s00259-020-04731-z ◽

2020 ◽

Vol 47 (10) ◽

pp. 2461-2468 ◽

Cited By ~ 3

Author(s):

Claire E. Owen ◽

Aurora M. T. Poon ◽

Victor Yang ◽

Christopher McMaster ◽

Sze Ting Lee ◽

...

Keyword(s):

Computed Tomography ◽

Positron Emission Tomography ◽

Sensitivity And Specificity ◽

Polymyalgia Rheumatica ◽

High Sensitivity ◽

Emission Tomography ◽

Whole Body ◽

Positron Emission

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Sub-millimeter nuclear medical imaging with high sensitivity in positron emission tomography using β+γ coincidences

Journal of Instrumentation ◽

10.1088/1748-0221/9/01/p01008 ◽

2014 ◽

Vol 9 (01) ◽

pp. P01008-P01008 ◽

Cited By ~ 27

Author(s):

C Lang ◽

D Habs ◽

K Parodi ◽

P G Thirolf

Keyword(s):

Positron Emission Tomography ◽

Medical Imaging ◽

High Sensitivity ◽

Emission Tomography ◽

Nuclear Medical Imaging ◽

Positron Emission

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Simulation Study for Designing a Dedicated Cardiac TOF-PET System

Sensors ◽

10.3390/s20051311 ◽

2020 ◽

Vol 20 (5) ◽

pp. 1311

Author(s):

Sandra Oliver ◽

Laura Moliner ◽

Víctor Ilisie ◽

J.M. Benlloch ◽

M.J. Rodríguez-Álvarez

Keyword(s):

Positron Emission Tomography ◽

Image Quality ◽

Lesion Detection ◽

Emission Tomography ◽

Cardiac Pet ◽

Tomography Scanners ◽

Optimal Geometry ◽

Positron Emission ◽

Image Quality Improvement ◽

Pet System

The development of dedicated positron emission tomography scanners is an active area of research, especially aiming at the improvement of lesion detection and in support of cancer treatment and management. Recently, dedicated Positron Emission Tomography (PET) systems with different configurations for specific organs have been developed for improving detection effectiveness. Open geometries are always subject to distortion and artifacts in the reconstructed images. Therefore, the aim of this work is to determine the optimal geometry for a novel cardiac PET system that will be developed by our team, and determine the time resolution needed to achieve reasonable image quality for the chosen geometry. The proposed geometries consist of 36 modules. These modules are arranged in two sets of two plates, each one with different configurations. We performed Monte Carlo simulations with different TOF resolutions, in order to test the image quality improvement in each case. Our results show, as expected, that increasing TOF resolution reduces distortion and artifact effects. We can conclude that a TOF resolution of the order of 200 ps is needed to reduce the artifacts, to acceptable levels, generated in the simulated cardiac-PET open geometries.

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