Is the Image Quality of I-124-PET Impaired by an Automatic Correction of Prompt Gammas?
Please always quote using this URN: urn:nbn:de:bvb:20-opus-96863
- Objectives The aim of this study is to evaluate the quality of I-124 PET images with and without prompt gamma compensation (PGC) by comparing the recovery coefficients (RC), the signal to noise ratios (SNR) and the contrast to F-18 and Ga-68. Furthermore, the influence of the PGC on the quantification and image quality is evaluated. Methods For measuring the image quality the NEMA NU2-2001 PET/SPECT-Phantom was used containing 6 spheres with a diameter between 10 mm and 37 mm placed in water with different levels of backgroundObjectives The aim of this study is to evaluate the quality of I-124 PET images with and without prompt gamma compensation (PGC) by comparing the recovery coefficients (RC), the signal to noise ratios (SNR) and the contrast to F-18 and Ga-68. Furthermore, the influence of the PGC on the quantification and image quality is evaluated. Methods For measuring the image quality the NEMA NU2-2001 PET/SPECT-Phantom was used containing 6 spheres with a diameter between 10 mm and 37 mm placed in water with different levels of background activity. Each sphere was filled with the same activity concentration measured by an independently cross-calibrated dose calibrator. The “hot” sources were acquired with a full 3D PET/CT (Biograph mCT®, Siemens Medical USA). Acquisition times were 2 min for F-18 and Ga-68, and 10 min for I-124. For reconstruction an OSEM algorithm was applied. For I-124 the images were reconstructed with and without PGC. For the calculation of the RCs the activity concentrations in each sphere were determined; in addition, the influence of the background correction was studied. Results The RCs of Ga-68 are the smallest (79%). I-124 reaches similar RCs (87% with PGC, 84% without PGC) as F-18 (84%). showing that the quantification of I-124 images is similar to F-18 and slightly better than Ga-68. With background activity the contrast of the I-124 PGC images is similar to Ga-68 and F-18 scans. There was lower background activity in the I-124 images without PGC, which probably originates from an overcorrection of the scatter contribution. Consequently, the contrast without PGC was much higher than with PGC. As a consequence PGC should be used for I-124. Conclusions For I-124 there is only a slight influence on the quantification depending on the use of the PGC. However, there are considerable differences with respect to I-124 image quality.…
Author: | Michael Lassmann, Veronika Preylowski, Susanne Schlögl, Frédéric Schoenahl, Gerhard Jörg, Samuel Samnick, Andreas K. Buck |
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URN: | urn:nbn:de:bvb:20-opus-96863 |
Document Type: | Journal article |
Faculties: | Medizinische Fakultät / Klinik und Poliklinik für Nuklearmedizin |
Language: | English |
Parent Title (English): | PLoS ONE |
Year of Completion: | 2013 |
Source: | In: PLoS ONE (2013) 8: 8, doi:10.1371/journal.pone.0071729 |
DOI: | https://doi.org/10.1371/journal.pone.0071729 |
Dewey Decimal Classification: | 6 Technik, Medizin, angewandte Wissenschaften / 61 Medizin und Gesundheit / 610 Medizin und Gesundheit |
Tag: | cancer treatment; health care; isotopes; photons; positron emission tomography; signal to noise ratio; super ultraviolet; thyroid carcinomas |
Release Date: | 2014/04/30 |
Collections: | Open-Access-Publikationsfonds / Förderzeitraum 2013 |
Licence (German): | CC BY: Creative-Commons-Lizenz: Namensnennung |