positron emission
Recently Published Documents


TOTAL DOCUMENTS

24503
(FIVE YEARS 7326)

H-INDEX

250
(FIVE YEARS 48)

Life ◽  
2022 ◽  
Vol 12 (1) ◽  
pp. 124
Author(s):  
Noriko Ishii-Kitano ◽  
Hirayuki Enomoto ◽  
Takashi Nishimura ◽  
Nobuhiro Aizawa ◽  
Yoko Shibata ◽  
...  

Inflammatory pseudotumor (IPT) of the liver is a rare benign disease. IPTs generally develop as solitary nodules, and cases with multiple lesions are uncommon. We herein report a case of multiple IPTs of the liver that spontaneously regressed. A 70-year-old woman with a 10-year history of primary biliary cholangitis and rheumatoid arthritis visited our hospital to receive a periodic medical examination. Abdominal ultrasonography revealed multiple hypoechoic lesions, with a maximum size of 33 mm, in the liver. Contrast-enhanced computed tomography revealed low-attenuation areas in the liver with mild peripheral enhancement at the arterial and portal phases. We first suspected metastatic liver tumors, but fluorodeoxyglucose positron emission tomography, magnetic resonance imaging and contrast-enhanced ultrasonography suggested the tumors to be inconsistent with malignant nodules. A percutaneous biopsy showed shedding of liver cells and abundant fibrosis with infiltration of inflammatory cells. Given these findings, we diagnosed the multiple tumors as IPTs. After careful observation for two months, the tumors almost vanished spontaneously. Physicians should avoid a hasty diagnosis of multiple tumors based solely on a few clinical findings, and a careful assessment with various imaging modalities should be conducted.


2022 ◽  
Author(s):  
Inés Califano ◽  
Fabian Pitoia ◽  
Roxana Chirico ◽  
Alejandra de Salazar ◽  
Maria Bastianello

Abstract Purpose 18F-DOPA Positron Emission Tomography/Computed Tomography (18F-DOPA PET/CT) is a sensitive functional imaging method (65-75%) for detecting disease localization in medullary thyroid cancer (MTC). We aimed: i) to assess the clinical usefulness of 18F-DOPA PET/CT in patients with MTC and elevated calcitonin (Ctn) and CEA levels and, ii) to evaluate changes in disease management secondary to the findings encountered with this methodology. Methods thirty-six patients with MTC and Ctn levels ≥150 pg/ml were prospectively included. Neck ultrasound, chest contrast-enhanced CT, liver magnetic resonance imaging/ abdominal 3-phase contrast-enhanced CT and bone scintigraphy were carried out up to 6 months before the 18F DOPA PET/CT. Results 77.7% were female and 27% had hereditary MTC. Median Ctn level was 1450 pg/ml [150-56620], median CEA level 413 ng/ml [2.9-7436]. Median Ctn DT was 37.5 months [5.7-240]; median CEA DT was 31.8 [4.9-180]. 18F-DOPA PET/CT was positive in 33 patients (91.6%); in 18 (56%) uptake was observed in lymph nodes in the neck or mediastinum, in 7 cases (22%) distant metastases were diagnosed, and in 8 additional patients (24%) both locoregional and distant sites of disease were found. Ctn and CEA levels were higher in patients with ≥ 3 foci of distant metastases. In 14 patients (38.8%), findings on 18F-DOPA PET/CT led to changes in management; surgery for locoregional lymph nodes was the most frequent procedure in 8 patients (22%). Conclusion 18F-DOPA PET/CT was useful for the detection of recurrent disease in MTC and provided helpful information for patient management.


2022 ◽  
Vol 15 ◽  
Author(s):  
Artur Agaronyan ◽  
Raeyan Syed ◽  
Ryan Kim ◽  
Chao-Hsiung Hsu ◽  
Scott A. Love ◽  
...  

The olive baboon (Papio anubis) is phylogenetically proximal to humans. Investigation into the baboon brain has shed light on the function and organization of the human brain, as well as on the mechanistic insights of neurological disorders such as Alzheimer’s and Parkinson’s. Non-invasive brain imaging, including positron emission tomography (PET) and magnetic resonance imaging (MRI), are the primary outcome measures frequently used in baboon studies. PET functional imaging has long been used to study cerebral metabolic processes, though it lacks clear and reliable anatomical information. In contrast, MRI provides a clear definition of soft tissue with high resolution and contrast to distinguish brain pathology and anatomy, but lacks specific markers of neuroreceptors and/or neurometabolites. There is a need to create a brain atlas that combines the anatomical and functional/neurochemical data independently available from MRI and PET. For this purpose, a three-dimensional atlas of the olive baboon brain was developed to enable multimodal imaging analysis. The atlas was created on a population-representative template encompassing 89 baboon brains. The atlas defines 24 brain regions, including the thalamus, cerebral cortex, putamen, corpus callosum, and insula. The atlas was evaluated with four MRI images and 20 PET images employing the radiotracers for [11C]benzamide, [11C]metergoline, [18F]FAHA, and [11C]rolipram, with and without structural aids like [18F]flurodeoxyglycose images. The atlas-based analysis pipeline includes automated segmentation, registration, quantification of region volume, the volume of distribution, and standardized uptake value. Results showed that, in comparison to PET analysis utilizing the “gold standard” manual quantification by neuroscientists, the performance of the atlas-based analysis was at >80 and >70% agreement for MRI and PET, respectively. The atlas can serve as a foundation for further refinement, and incorporation into a high-throughput workflow of baboon PET and MRI data. The new atlas is freely available on the Figshare online repository (https://doi.org/10.6084/m9.figshare.16663339), and the template images are available from neuroImaging tools & resources collaboratory (NITRC) (https://www.nitrc.org/projects/haiko89/).


2022 ◽  
Vol 12 (2) ◽  
pp. 823
Author(s):  
Md. Rafiqul Islam ◽  
Mehrdad Shahmohammadi Beni ◽  
Shigeki Ito ◽  
Shinichi Gotoh ◽  
Taiga Yamaya ◽  
...  

Proton range monitoring and verification is important to enhance the effectiveness of treatment by ensuring that the correct dose is delivered to the correct location. Upon proton irradiation, different positron emitting radioisotopes are produced by the inelastic nuclear interactions of protons with the target elements. Recently, it was reported that the 16O(p,2p2n)13N reaction has a relatively low threshold energy, and it could be potentially used for proton range verification. In the present work, we have proposed an analysis scheme (i.e., algorithm) for the extraction and three-dimensional visualization of positron emitting radioisotopes. The proposed step-by-step analysis scheme was tested using our own experimentally obtained dynamic data from a positron emission mammography (PEM) system (our developed PEMGRAPH system). The experimental irradiation was performed using an azimuthally varying field (AVF) cyclotron with a 80 MeV monoenergetic pencil-like beam. The 3D visualization showed promising results for proton-induced radioisotope distribution. The proposed scheme and developed tools would be useful for the extraction and 3D visualization of positron emitting radioisotopes and in turn for proton range monitoring and verification.


2022 ◽  
Author(s):  
Steven P. Rowe ◽  
Andreas Buck ◽  
Ralph A. Bundschuh ◽  
Constantin Lapa ◽  
Sebastian E. Serfling ◽  
...  

AbstractProstate-specific membrane antigen (PSMA)-directed positron emission tomography (PET) has gained increasing interest for imaging of men affected by prostate cancer (PC). In recent years, 68Ga-labeled PSMA compounds have been widely utilized, although there is a trend towards increased utilization of 18F-labeled agents. Among others, [18F]DCFPyL (piflufolastat F 18, PYLARIFY) has been tested in multiple major trials, such as OSPREY and CONDOR, which provided robust evidence on the clinical utility of this compound for staging, restaging, and change in management. Recent explorative prospective trials have also utilized [18F]DCFPyL PET/CT for response assessment, e.g., in patients under abiraterone or enzalutamide, rendering this 18F-labeled PSMA radiotracer as an attractive biomarker for image-guided strategies in men with PC. After recent approval by the U.S. Food and Drug Administration, one may expect more widespread use, not only in the U.S., but also in Europe in the long term. In the present review, we will provide an overview of the current clinical utility of [18F]DCFPyL in various clinical settings for men with PC.


2022 ◽  
Vol 11 (2) ◽  
pp. 386
Author(s):  
Kim-Heang Ly ◽  
Nathalie Costedoat-Chalumeau ◽  
Eric Liozon ◽  
Stéphanie Dumonteil ◽  
Jean-Pierre Ducroix ◽  
...  

Fluorodesoxyglucose Positron Emission Tomography (PET/CT) has never been compared to Chest-Abdomen-Pelvis CT (CAPCT) in patients with a fever of unknown origin (FUO), inflammation of unknown origin (IUO) and episodic fever of unknown origin (EFUO) through a prospective and multicentre study. In this study, we investigated the diagnostic value of PET/CT compared to CAPCT in these patients. The trial was performed between 1 May 2008 through 28 February 2013 with 7 French University Hospital centres. Patients who fulfilled the FUO, IUO or EFUO criteria were included. Diagnostic orientation (DO), diagnostic contribution (DC) and time for diagnosis of both imaging resources were evaluated. One hundred and three patients were included with 35 FUO, 35 IUO and 33 EFUO patients. PET/CT showed both a higher DO (28.2% vs. 7.8%, p < 0.001) and DC (19.4% vs. 5.8%, p < 0.001) than CAPCT and reduced the time for diagnosis in patients (3.8 vs. 17.6 months, p = 0.02). Arthralgia (OR 4.90, p = 0.0012), DO of PET/CT (OR 4.09, p = 0.016), CRP > 30 mg/L (OR 3.70, p = 0.033), and chills (OR 3.06, p = 0.0248) were associated with the achievement of a diagnosis (Se: 89.1%, Sp: 56.8%). PET/CT both orients and contributes to diagnoses at a higher rate than CAPCT, especially in patients with FUO and IUO, and reduces the time for diagnosis.


Author(s):  
David Lopes Sousa ◽  
Sandra D. Santos ◽  
João Pina Cabral ◽  
Ricardo Velho ◽  
Ana Sofia Teixeira ◽  
...  

Primary adrenal lymphoma (PAL) is a very rare type of non-Hodgkin’s lymphoma (NHL). Herein, we report a case of NHL of both adrenal glands in a 69-year-old man. The patient was admitted because of a 1-month history of B symptoms and symptomatic hypotension. Biochemical analysis showed normocytic normochromic anaemia, hyponatraemia, hyperkalaemia, and elevated lactate dehydrogenase, C-reactive protein and D-dimers. A computed tomography scan revealed bilateral enlargement of the adrenal glands. There was no evidence of endocrine adrenal dysfunction. The mass in the right adrenal gland was biopsied and histopathology identified a diffuse large B-cell lymphoma of the activated B-cell subtype. A positron emission tomography 18F-fluorodeoxyglucose scan showed intensive hypermetabolic lesions involving both adrenal glands, as well as other locations, with higher uptake in the adrenal glands. Taken together, these findings suggested the diagnosis of PAL. The patient responded favourably to debulking therapy and is currently undergoing chemotherapy.


2022 ◽  
Author(s):  
Justine Hansen ◽  
Golia Shafiei ◽  
Ross Markello ◽  
Kelly Smart ◽  
Sylvia Cox ◽  
...  

Abstract Neurotransmitter receptors support the propagation of signals in the human brain. How receptor systems are situated within macroscale neuroanatomy and how they shape emergent function remains poorly understood, and there exists no comprehensive atlas of receptors. Here we collate positron emission tomography scans in >1,200 healthy individuals to construct a whole-brain 3-D normative atlas of 18 receptors and transporters across 9 different neurotransmitter systems. We find that receptor profiles align with structural connectivity and mediate function, including neurophysiological oscillatory dynamics and resting state hemodynamic functional connectivity. Using the Neurosynth cognitive atlas, we uncover a topographic gradient of overlapping receptor distributions that separates extrinsic and intrinsic psychological processes. Finally, we find both expected and novel associations between receptor distributions and cortical thinning patterns across 13 disorders. We replicate all findings in an independently collected autoradiography dataset. This work demonstrates how chemoarchitecture shapes brain structure and function, providing a new direction for studying multi-scale brain organization.


Sign in / Sign up

Export Citation Format

Share Document