Assessment of Accuracy of PET Utilizing a 3-D Phantom to Simulate the Activity Distribution of [18F]Fluorodeoxyglucose Uptake in the Human Brain

A three-dimensional brain phantom has been developed to simulate the activity distributions found in human brain studies currently employed in positron emission tomography (PET). The phantom has a single contiguous chamber and utilizes thin layers of lucite to provide apparent relative concentrations of 5, 1, and 0 for gray matter, white matter, and CSF structures, respectively. The phantom and an ideal image set were created from the same set of data. Thus, the user has a basis for comparing measured images with an ideal set that allows a quantitative evaluation of errors in PET studies with an activity distribution similar to that found in patients. The phantom was employed in a study of the effect of deadtime and scatter on accuracy in quantitation on a current PET system. Deadtime correction factors were found to be significant (1.1–2.5) at count rates found in clinical studies. Deadtime correction techniques were found to be accurate to within 5%. Scatter in emission and attenuation correction data consistently caused 5–15% errors in quantitation, whereas correction for scatter in both types of data reduced errors in accuracy to <5%.

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Automatic Brain Cancer Segmentation on PET Image

International Journal of Pattern Recognition and Artificial Intelligence ◽

10.1142/s0218001421500087 ◽

2020 ◽

pp. 2150008

Author(s):

Ching-Lin Wang ◽

Chi-Shiang Chan ◽

Wei-Jyun Wang ◽

Yung-Kuan Chan ◽

Meng-Hsiun Tsai ◽

...

Keyword(s):

Brain Tumor ◽

3D Model ◽

Early Stage ◽

Three Dimensional ◽

Ground Truth ◽

Emission Tomography ◽

Segmentation Method ◽

Brain Images ◽

Positron Emission ◽

Image Set

When treating a brain tumor, a doctor needs to know the site and the size of the tumor. Positron emission tomography (PET) can be effectively applied to diagnose such cancers based on the heightened glucose metabolism of early-stage cancer cells. The purpose of this research is to extract the regions of skull, brain tumor, and brain tissue from a series of PET brain images and then a three-dimensional (3D) model is reconstructed from the extracted skulls, brain tumors, and brain tissues. Knowing the relative site and size of a tumor within the skull is helpful to a doctor. The contours obtained by the segmentation method proposed in this study are quantitatively compared with the contours drawn by doctors on the same image set since the ground truth is unknown. The experimental results are impressive.

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Toward a neuroscope: An application of high-performance computing for real-time evaluation of brain function using MRI

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100172346 ◽

1994 ◽

Vol 52 ◽

pp. 922-923

Author(s):

C. S. Potter ◽

C. D. Gregory ◽

H. D. Morris ◽

Z.-P. Liang ◽

P. C. Lauterbur

Keyword(s):

Human Brain ◽

Brain Function ◽

High Performance ◽

Complex Signal ◽

Time Step ◽

Brain Organization ◽

Cognitive Studies ◽

Positron Emission ◽

Imaging And Spectroscopy ◽

3D Anatomy

Over the past few years, several laboratories have demonstrated that changes in local neuronal activity associated with human brain function can be detected by magnetic resonance imaging and spectroscopy. Using these methods, the effects of sensory and motor stimulation have been observed and cognitive studies have begun. These new methods promise to make possible even more rapid and extensive studies of brain organization and responses than those now in use, such as positron emission tomography.Human brain studies are enormously complex. Signal changes on the order of a few percent must be detected against the background of the complex 3D anatomy of the human brain. Today, most functional MR experiments are performed using several 2D slice images acquired at each time step or stimulation condition of the experimental protocol. It is generally believed that true 3D experiments must be performed for many cognitive experiments. To provide adequate resolution, this requires that data must be acquired faster and/or more efficiently to support 3D functional analysis.

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Human brain regions responsive to visual motion stimuli: determination by magnetoencephalography and three dimensional MRI

Neuroscience Research ◽

10.1016/s0168-0102(00)81117-7 ◽

2000 ◽

Vol 38 ◽

pp. S45

Author(s):

M Bundo

Keyword(s):

Human Brain ◽

Visual Motion ◽

Three Dimensional ◽

Brain Regions

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Construction and verification of a three-dimensional digital human brain atlas

Academic Journal of Second Military Medical University ◽

10.3724/sp.j.1008.2011.00291 ◽

2011 ◽

Vol 31 (3) ◽

pp. 291-294

Author(s):

Zhi-rong YANG ◽

Yong-jie LI ◽

Teng MA

Keyword(s):

Human Brain ◽

Three Dimensional ◽

Brain Atlas ◽

Digital Human

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Effect Of Phosphorus On Ge/Si(001) Island Formation

MRS Proceedings ◽

10.1557/proc-737-f2.4 ◽

2002 ◽

Vol 737 ◽

Author(s):

Theodore I. Kamins ◽

Gilberto Medeiros-Ribeiro ◽

Douglas A. A. Ohlberg ◽

R. Stanley Williams

Keyword(s):

Deposition Rate ◽

Strain Energy ◽

Competitive Adsorption ◽

Lattice Mismatch ◽

Three Dimensional ◽

Deposition Process ◽

Thin Layers ◽

Island Size ◽

Partial Pressures ◽

Intermediate Size

ABSTRACTWhen Ge is deposited epitaxially on Si, the strain energy from the lattice mismatch causes the Ge in layers thicker than about four monolayers to form distinctive, three-dimensional islands. The shape of the islands is determined by the energies of the surface facets, facet edges, and interfaces. When phosphorus is added during the deposition, the surface energies change, modifying the island shapes and sizes, as well as the deposition process. When phosphine is introduced to the germane/hydrogen ambient during Ge deposition, the deposition rate decreases because of competitive adsorption. The steady-state deposition rate is not reached for thin layers. The deposited, doped layers contain three different island shapes, as do undoped layers; however, the island size for each shape is smaller for the doped layers than for the corresponding undoped layers. The intermediate-size islands are the most significant; the intermediate-size doped islands are of the same family as the undoped, multifaceted “dome” structures, but are considerably smaller. The largest doped islands appear to be related to the defective “superdomes” discussed for undoped islands. The distribution between the different island shapes depends on the phosphine partial pressure. At higher partial pressures, the smaller structures are absent. Phosphorus appears to act as a mild surfactant, suppressing small islands.

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Acute acetate administration increases endogenous opioid levels in the human brain: A [11C]carfentanil molecular imaging study

Journal of Psychopharmacology ◽

10.1177/0269881120965912 ◽

2021 ◽

pp. 026988112096591

Author(s):

Abhishekh H Ashok ◽

Jim Myers ◽

Gary Frost ◽

Samuel Turton ◽

Roger N Gunn ◽

...

Keyword(s):

Human Brain ◽

Sodium Acetate ◽

Statistical Significance ◽

Imaging Study ◽

Pet Scan ◽

Endogenous Opioid ◽

Reference Tissue ◽

Healthy Human ◽

Fourfold Increase ◽

Positron Emission

Introduction: A recent study has shown that acetate administration leads to a fourfold increase in the transcription of proopiomelanocortin (POMC) mRNA in the hypothalamus. POMC is cleaved to peptides, including β-endorphin, an endogenous opioid (EO) agonist that binds preferentially to the µ-opioid receptor (MOR). We hypothesised that an acetate challenge would increase the levels of EO in the human brain. We have previously demonstrated that increased EO release in the human brain can be detected using positron emission tomography (PET) with the selective MOR radioligand [11C]carfentanil. We used this approach to evaluate the effects of an acute acetate challenge on EO levels in the brain of healthy human volunteers. Methods: Seven volunteers each completed a baseline [11C]carfentanil PET scan followed by an administration of sodium acetate before a second [11C]carfentanil PET scan. Dynamic PET data were acquired over 90 minutes, and corrected for attenuation, scatter and subject motion. Regional [11C] carfentanil BPND values were then calculated using the simplified reference tissue model (with the occipital grey matter as the reference region). Change in regional EO concentration was evaluated as the change in [11C]carfentanil BPND following acetate administration. Results: Following sodium acetate administration, 2.5–6.5% reductions in [11C]carfentanil regional BPND were seen, with statistical significance reached in the cerebellum, temporal lobe, orbitofrontal cortex, striatum and thalamus. Conclusions: We have demonstrated that an acute acetate challenge has the potential to increase EO release in the human brain, providing a plausible mechanism of the central effects of acetate on appetite in humans.

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Fast Nonsupervised 3D Registration of PET and MR Images of the Brain

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.1994.96 ◽

1994 ◽

Vol 14 (5) ◽

pp. 749-762 ◽

Cited By ~ 66

Author(s):

Jean-François Mangin ◽

Vincent Frouin ◽

Isabelle Bloch ◽

Bernard Bendriem ◽

Jaime Lopez-Krahe

Keyword(s):

Three Dimensional ◽

Magnetic Resonance Images ◽

Surface Matching ◽

3D Registration ◽

Matching Algorithm ◽

Distance Map ◽

Brain Surface ◽

Discrete Surfaces ◽

Positron Emission ◽

The Brain

We propose a fully nonsupervised methodology dedicated to the fast registration of positron emission tomography (PET) and magnetic resonance images of the brain. First, discrete representations of the surfaces of interest (head or brain surface) are automatically extracted from both images. Then, a shape-independent surface-matching algorithm gives a rigid body transformation, which allows the transfer of information between both modalities. A three-dimensional (3D) extension of the chamfer-matching principle makes up the core of this surface-matching algorithm. The optimal transformation is inferred from the minimization of a quadratic generalized distance between discrete surfaces, taking into account between-modality differences in the localization of the segmented surfaces. The minimization process is efficiently performed via the precomputation of a 3D distance map. Validation studies using a dedicated brain-shaped phantom have shown that the maximum registration error was of the order of the PET pixel size (2 mm) for the wide variety of tested configurations. The software is routinely used today in a clinical context by the physicians of the Service Hospitalier Frédéric Joliot (>150 registrations performed). The entire registration process requires ∼5 min on a conventional workstation.

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