PET/CT NEMA Body Phantom Image Reconstruction Study Using 2 mm Voxel Size for Improved Image Quality

Abstract Background PET/CT imaging is widely used in oncology and provides both metabolic and anatomic information. Because of the relatively poor spatial resolution of PET/CT imaging technique the detection of small lesions is limited. The low spatial resolution introduces the partial-volume effect (PVE) which negatively affects images both visually and quantitatively. The aim of our research was to investigate the effect of 4 mm and 2 mm voxel size on image quality and on detection of small spheres. MethodsWe used the NEMA body phantom with six fillable spheres. The spheres and background were filled with a solution of 18F-FDG, in ratio spheres vs background 2:1, 3:1, 4:1 and 8:1 In all images reconstructed with 2 mm and 4 mm voxel size the contrast recovery coefficient (CRC), contrast to noise ratio (CNR) in standardized uptake value (SUV) were evaluated.ResultsFor phantom spheres ≤ 13 mm, we found significant higher CRC, SUV and CNR using small-voxel reconstructions. CRC and SUV did not differ for large spheres (≥ 17 mm) using 2 mm and 4 mm voxel size. On the other hand, CNR for large spheres (≥ 17 mm) was significantly decreased in 2 mm voxel size images compared to the 4 mm.ConclusionAccording to our results, the reconstruction with 2 mm voxel size can improve precise lesion localization, image contrast, and image quality.

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Comparison of Image Quality and Spatial Resolution Between 18F, 68Ga and 64Cu Phantom Measurements Using a Digital Biograph Vision PET/CT

10.21203/rs.3.rs-1159557/v1 ◽

2022 ◽

Author(s):

Anja Braune ◽

Liane Oehme ◽

Robert Freudenberg ◽

Frank Hofheinz ◽

Jörg van den Hoff ◽

...

Keyword(s):

Image Quality ◽

Spatial Resolution ◽

Ct Scans ◽

Reconstruction Method ◽

Recovery Coefficient ◽

Positron Energy ◽

Pet Ct ◽

The Individual ◽

The Impact

Abstract Background: The PET nuclide and reconstruction method can have a considerable influence on spatial resolution and image quality of PET/CT scans, which can, for example, influence the diagnosis in oncology. The individual impact of the positron energy of 18F, 68Ga and 64Cu on spatial resolution and image quality of PET/CT scans acquired using a clinical, digital scanner was compared. Furthermore, the impact of different reconstruction parameters on image quality and spatial resolution was evaluated for 18F-FDG PET/CT scans acquired with a scanner of the newest generation. Methods: PET/CT scans of a Jaszczak phantom and a NEMA PET body phantom, filled with 18F-FDG, 68Ga-HCl and 64Cu-HCl, respectively, were performed on a Siemens Biograph Vision. Images were assessed using spatial resolution and image quality (Recovery Coefficients (RC), coefficient of variation within the background, Contrast Recovery Coefficient (CRC), Contrast-Noise-Ratio (CNR), and relative count error in lung insert). In a subsequent analysis, the scan of the NEMA PET body phantom filled with 18F-FDG was reconstructed applying different parameters (with/without the application of Point Spread Function (PSF), Time of Flight (ToF) or post-filtering; matrix size). Spatial resolution and quantitative image quality were compared between reconstructions. Results: We found that image quality was comparable between 18F-FDG and 64Cu-HCl PET/CT measurements featuring similar maximal endpoint energy. In comparison, RC, CRC and CNR were worse in 68Ga-HCl data, despite similar count rates. Spatial resolution was up to 18 % worse in 68Ga-HCl compared to 18F-FDG images. Post-filtering of 18F-FDG acquisitions changed image quality the most and reduced spatial resolution by 52 % if a Gaussian filter with 5 mm FWHM was applied. ToF measurements especially improved the recovery of the smallest lesion (RCmean = 1.07 compared to 0.65 without ToF) and improved spatial resolution by 29 %.Conclusions: The positron energy of PET nuclides influences spatial resolution and image quality of digital PET/CT scans. Image quality of 68Ga-HCl PET/CT images was worse compared to 18F-FDG and 64Cu-HCl, respectively, despite similar count rates. Reconstruction parameters have a high impact on image quality and spatial resolution and should be considered when comparing images of different scanners or centers.

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Can the BMI-based dose regimen be used to reduce injection activity and to obtain a constant image quality in oncological patients by 18F-FDG total-body PET/CT imaging?

European Journal of Nuclear Medicine and Molecular Imaging ◽

10.1007/s00259-021-05462-5 ◽

2021 ◽

Author(s):

Jie Xiao ◽

Haojun Yu ◽

Xiuli Sui ◽

Yan Hu ◽

Yanyan Cao ◽

...

Keyword(s):

Image Quality ◽

Dose Regimen ◽

Ct Imaging ◽

Oncological Patients ◽

Pet Ct ◽

18F Fdg ◽

Total Body

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An Automatic System for Analyzing Phantom Images to Determine the Reliability of PET/SPECT Cameras

Volume 3: 17th International Conference on Advanced Vehicle Technologies; 12th International Conference on Design Education; 8th Frontiers in Biomedical Devices ◽

10.1115/detc2015-46254 ◽

2015 ◽

Author(s):

Miri Weiss Cohen ◽

John A. Kennedy ◽

Archil Pirmisashvili ◽

Gleb Orlikov

Keyword(s):

Quality Control ◽

Image Quality ◽

Spatial Resolution ◽

Automatic System ◽

Quality Parameters ◽

Tomographic Image ◽

Performance Parameters ◽

Pet Ct ◽

Ct Scanners

This paper describes an automatic system for analyzing phantom images from two types of PET/CT scanners. The system was developed for the purpose of obtaining tomographic image quality parameters, which determine a number of different performance parameters, primarily scanner sensitivity, tomographic uniformity, contrast and spatial resolution. The system provides a method for generating and altering image masks used for the analysis of PET images, which are then automatically aligned with the PET data. The system automatically generates Quality Control (QC) reports and is currently being used at clinical PET/CT center.

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Recent applications of nuclear medicine in diagnostics (I part)

Italian Journal of Medicine ◽

10.4081/itjm.2010.84 ◽

2013 ◽

pp. 84-91 ◽

Cited By ~ 2

Author(s):

Giorgio Treglia ◽

Ernesto Cason ◽

Giorgio Fagioli

Keyword(s):

Nuclear Medicine ◽

Neuroendocrine Tumours ◽

High Spatial Resolution ◽

Cellular Level ◽

Ct Imaging ◽

Imaging Systems ◽

Lymph Node Mapping ◽

Pet Ct ◽

Anatomic Information

Introduction: Aim of this review is to describe the recent applications of nuclear medicine techniques in diagnostics, particularly in oncology. Materials and methods: We reviewed scientific literature data searching for the current role of tomographic nuclear medicine techniques (SPECTand PET) in oncology and summarized the main applications of these techniques. Results: Nuclear medicine techniques have a key role in oncology allowing early diagnosis of many tumours, an accurate staging of disease and evalutation of treatment response. Hybrid SPECT/CT and PET/CT imaging systems now provide metabolic and functional information from SPECTor PETcombined with the high spatial resolution and anatomic information of CT. The most frequent applications of SPECT/CT in oncology concern thyroid tumours, neuroendocrine tumours, bone metastases and lymph node mapping. Furthermore the evaluation of many tumours may benefit from PET/CT imaging. Discussion: The recent development of new radiopharmaceuticals and the growth of hybrid tomographic devices, such as SPECT/CT and PET/CT, now permits molecular imaging of biologic processes at the cellular level to improve both the diagnosis and treatment of many tumours.

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The Impact of Varying Number of OSEM Iterations on Standardized Uptake Value and Image Quality of Discovery STE PET/CT Scanner

Journal of Global Oncology ◽

10.1200/jgo.18.33600 ◽

2018 ◽

Vol 4 (Supplement 2) ◽

pp. 68s-68s

Author(s):

B. Ali ◽

A. Afshan ◽

M.B. Kakakhel

Keyword(s):

Image Quality ◽

Standardized Uptake Value ◽

Acquisition Time ◽

List Mode ◽

Ct Scanner ◽

Matrix Size ◽

Cold Lesion ◽

Pet Ct ◽

The Impact

Background: In PET imaging both quantitative and qualitative interpretations are used. Qualitative and quantitative interpretations depend upon PET/CT image quality that along with many biologic factors strongly depends upon image reconstruction parameters. Aim: The objective of this experimental work was to study the impact of one of the key reconstruction parameter, i.e., number of reconstruction iteration, on standardized uptake value and image quality of PET/CT scan. Methods: Images of NEMA IEC Image Quality Phantom were acquired in list mode for 10 mins on Discovery STE PET/CT scanner, using tumor to background ratio of 4:1 and 18F-FDG as radiotracer. List mode data were further transformed into data sets of varying acquisition time (0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0 mins) per bed position. Transformed data set of 5.0 mins were used to study the impact of varying number of iterations (2, 3, 4, 5, 7, 10, 15, 20) using OSEM approach of iterative reconstruction. Standardized uptake value (SUV) and underestimation in SUV were calculated as quantitative measures, while hot lesion contrast, cold lesion contrast and background variability were calculated as qualitative measures. Results: Standardized uptake value, hot and cold lesion contrast, image spatial resolution and background variability showed increasing trend with increase in reconstruction iterations. Maximum increase of 20.25%, 16.33%, 9.79% and 6.88% was observed in SUV for 10 mm, 13 mm, 17 mm and 22 mm lesions as number of iteration change from 2 to 3. Smallest and the largest diameter lesions showed maximum underestimations of 54.67% and 8.20% at 2 iterations respectively. Percentage hot lesion contrast showed rapid increase as the number of iteration change from 2 to 7 and increased slowly afterward. Background variability range from 4.4% to 6.4%, 4.1%–5.7%, 3.6%–4.6%, 3%–3.8%, 2.7%–3.2%, 2.4%–2.7% for 10.0 mm, 13.0 mm, 17.0 mm, 22.0 mm, 28.0 mm and 37.0 mm sphere respectively. Conclusion: Optimized reconstruction parameters for routine clinical studies 3 iterations with image matrix size of 128 × 128 with filters FWHM of 6 mm and for high resolution studies 3 iterations image matrix size of 256×256 with filters FWHM of 6 mm.

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Assessment of MicroPET Image Quality Based on Reconstruction Methods and Post-Filtering

Applied Sciences ◽

10.3390/app11188707 ◽

2021 ◽

Vol 11 (18) ◽

pp. 8707

Author(s):

Hyeon-Sik Kim ◽

Byeong-il Lee ◽

Jae-Sung Ahn

Keyword(s):

Image Quality ◽

Volume Effect ◽

Partial Volume Effect ◽

Emission Tomography ◽

Recovery Coefficient ◽

Filtering Method ◽

Reconstruction Methods ◽

Positron Emission ◽

Image Blurring ◽

Selection Of

The accuracy of positron emission tomography (PET) imaging is hampered by the partial volume effect (PVE), which causes image blurring and sampling. The PVE produces spillover phenomena, making PET analysis difficult. Generally, the PVE values vary based on reconstruction methods and filtering. Thus, selection of the proper reconstruction and filtering method can ensure accurate and high-quality PET images. This study compared the values of factors (recovery coefficient (RC), uniformity, and spillover ratio (SOR)) associated with different reconstruction and post-filtering methods using a mouse image quality phantom (NEMA NU 4), and we present an effective approach for microPET images. The PET images were obtained using a microPET scanner (Inveon, Siemens Medical Solutions, Malvern, PA, USA). PET data were reconstructed and/or post-filtered. For tumors smaller than 3 mm, iterative reconstruction methods provided better image quality. For tumor sizes bigger than 3 mm, reconstruction methods without post-filtering showed better results.

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Proliferation PET/CT Imaging of Salivary Gland Tumor

Diagnostics ◽

10.3390/diagnostics11112065 ◽

2021 ◽

Vol 11 (11) ◽

pp. 2065

Author(s):

Ryogo Minamimoto

Keyword(s):

Salivary Gland ◽

Salivary Gland Tumor ◽

Standardized Uptake Value ◽

Ct Imaging ◽

Salivary Gland Tumors ◽

Parotid Carcinoma ◽

Positron Emission ◽

Pet Ct ◽

Significant Difference ◽

Malignant Salivary Gland Tumors

Salivary gland tumors are rare neoplasms which vary in terms of origin and malignant potential. 2-[18F]-fluoro-2-deoxy-d-glucose (FDG)-positron emission tomography (PET) has limited ability to differentiate between different types of salivary gland tumors because both Warthin’s tumors and pleomorphic adenomas usually show increased FDG uptake, with no statistically significant difference in standardized uptake value (SUV) compared with malignant salivary gland tumors. Here, we discuss 4′-[methyl-11C]-thiothymidine (4DST) PET, which provides cell proliferation imaging capable of demonstrating intense uptake in parotid carcinoma and Warthin’s tumor, but no uptake in parotid pleomorphic adenoma. This is the first report of the potential of proliferation PET/ computed tomography (CT) imaging for characterizing salivary gland tumors based on the molecular pathogenesis of the tumor.

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