Objective: The purpose of this study was to investigate the effect of attenuation correction (AC) on lesion detection for a hybrid PET system.
Material And Method: Experimental list-mode data were acquired from hot spheres inside a uniform cylindrical phantom with an elliptical cross-section using a Siemens E. CAM+ dual-camera hybrid PET system. Spheres with inner diameters of 0.8- and 1-cm and the cylindrical phantom were filled with F-18 to simulate lesions with lesion-to-background (L/B) ratios of 14:1 and 8:1, respectively, found in clinical PET studies. The list-mode data of each sphere size were regrouped into sinograms with peak-to-peak energy window settings at 30% and 20% for the 0.8- and 1-cm diameter lesion, respectively. They were then rebinned using the single slice rebinning method. Attenuation correction was applied assuming uniform attenuation. The sinograms with and without AC were reconstructed using 5 iterations of OS-EM algorithm with 8 angles/ subset and postfiltered with a Butterworth filter with n = 5 and fc = 0.52 cycles/cm. Human observer performance study and localization receiver operating characteristic (LROC) analysis were used to evaluate the reconstructed images for maximum lesion detection. Average areas under the LROC curves (A(LROC)) across 8 observers obtained with and without AC were determined. The null hypothesis that there was no difference between with AC and without AC was tested using a two-tailed t-test with 95% confidence interval.
Results: The results indicated that for the 0. 8-cm lesion with 14:1 L/B ratio, the A(LROC) decreases from 0.66 to 0.62 when AC is applied as compared to without AC andfrom 0.69 to 0.63 for the 1.0-cm lesion with 8:1 L/ B ratio, but no statistical significant difference (p > 0. 05).
Conclusion: The authors conclude that for a phantom with hot lesions embedded in a uniform background, AC decreases lesion detectability compared to without AC using a hybrid PET system for small lesion sizes.
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Int J Surg Pathol
January 2025
Department of Pathology, All India Institute of Medical Sciences, New Delhi, India.
Metastasis of alveolar soft part sarcoma (ASPS) to the adrenal gland is infrequent, with only eight patients reported in the literature. Here we present an ASPS in an adolescent girl presented as a hypervascular adrenal incidentaloma along with a review of the available literature. This study aims to serve as a reference to aid in the pre-operative radiological and histopathological diagnosis of this rare entity.
View Article and Find Full Text PDFDiagnostics (Basel)
January 2025
Division of Nuclear Medicine, Imaging Institute of Southern Switzerland, Ente Ospedaliero Cantonale, 6500 Bellinzona, Switzerland.
Here, we describe the case of a 74-year-old male patient with a high-risk prostate carcinoma who underwent positron-emission tomography/computed tomography (PET/CT) with [Ga]Ga-prostate-specific membrane antigen ([Ga]Ga-PSMA-11) for staging. [Ga]Ga-PSMA-11 PET/CT detected an extensive area of increased tracer uptake at the prostatic level, involving both lobes. Additionally, a rounded lesion approximately 4 cm in diameter was identified in the celiac region adjacent to the stomach, exhibiting moderate tracer uptake.
View Article and Find Full Text PDFJ Am Coll Cardiol
November 2024
British Heart Foundation Centre of Research Excellence, the University of Edinburgh, Edinburgh, Scotland, United Kingdom.
Background: Myocardial fibrosis is a key healing response after myocardial infarction driven by activated fibroblasts. Gallium-68-labeled fibroblast activation protein inhibitor ([Ga]-FAPI) is a novel positron-emitting radiotracer that binds activated fibroblasts.
Objectives: The aim of this study was to investigate the intensity, distribution, and time-course of fibroblast activation after acute myocardial infarction.
Animals (Basel)
December 2024
Division of Artificial Intelligence Engineering, National Korea Maritime & Ocean University, Busan 49112, Republic of Korea.
While the pet market is continuously rapidly increasing in Korea, pet dog owners feel uncomfortable in coping with pet dog's health problems in time. In this paper, we propose a pre-diagnosis system based on neuro-fuzzy learning, enabling non-expert users to monitor their pets' health by inputting observed symptoms. To develop such a system, we form a disease-symptom database based on several textbooks with veterinarians' guidance and filtering.
View Article and Find Full Text PDFEur J Nucl Med Mol Imaging
January 2025
Huashan Hospital and Human Phenome Institute, Fudan University, 220 Handan Road, Shanghai, 200433, China.
Objective: This study aims to conduct a bibliometric analysis to explore research trends, collaboration patterns, and emerging themes in the PET/MR field based on published literature from 2010 to 2024.
Methods: A detailed literature search was performed using the Web of Science Core Collection (WoSCC) database with keywords related to PET/MR. A total of 4,349 publications were retrieved and analyzed using various bibliometric tools, including VOSviewer and CiteSpace.
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