Introduction: Yttrium-90 ( Y) microsphere post-treatment imaging reflects the true distribution characteristics of microspheres in the tumor and liver compartments. However, due to its decay spectra profile lacking a pronounced photopeak, the bremsstrahlung imaging for Y has inherent limitations. The absorbed dose calculations for Y microspheres radiomicrosphere therapy (RMT) sustain a limitation due to the poor quality of Y imaging. The aim of this study was to develop quantitative methods to improve the post-treatment Y bremsstrahlung single photon emission tomography (SPECT)/computed tomography (CT) image analysis for dosimetric purposes and to perform a quantitative comparison with the Tc-MAA SPECT/CT images, which is used for theranostics purposes for liver and tumor dosimetry.
Methods: Pre and post-treatment SPECT/CT data of patients who underwent RMT for primary or metastatic liver cancer were acquired. A Jasczak phantom with eight spherical inserts of various sizes was used to obtain optimal iteration number for the contrast recovery algorithm for improving Y bremsstrahlung SPECT/CT images. Comparison of uptake on Tc-MAA and Y microsphere SPECT/CT images was assessed using tumor to healthy liver ratios (TLRs). The voxel dosimetry technique was used to estimate absorbed doses. Absorbed doses within the tumor and healthy part of the liver were also investigated for correlation with administered activity.
Results: Improvement in CNR and contrast recovery coefficients on patient and phantom Y bremsstrahlung SPECT/CT images respectively were achieved. The Tc-MAA and Y microspheres SPECT/CT images showed significant uptake correlation (r = 0.9, P = 0.05) with mean TLR of 9.4 ± 9.2 and 5.0 ± 2.2, respectively. The correlation between the administered activity and tumor absorbed dose was weak (r = 0.5, P > 0.05), however, healthy liver absorbed dose increased with administered activity (r = 0.8, P = 0.0).
Conclusions: This study demonstrated correlation in mean TLR between Tc-MAA and Y microsphere SPECT/CT.
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http://dx.doi.org/10.1002/acm2.12512 | DOI Listing |
Sci Rep
December 2024
Department of Oral and Maxillofacial Surgery, Yonsei University College of Dentistry, Gangnam Severance Hospital, 211 Eonju-ro, Gangnam-gu, Seoul, 06273, Republic of Korea.
This study aimed to investigate the cutoff values of standardized uptake values (SUVs) and their accuracy using single-photon emission computed tomography-computed tomography (SPECT-CT) for temporomandibular joint (TMJ) osteoarthritis (OA) based on magnetic resonance imaging (MRI) and clinical examination. We included 106 joints of 53 patients with TMJ OA. SUVmax and SUVpeak of each TMJ was measured.
View Article and Find Full Text PDFClin Radiol
December 2024
Department of Cardiology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, 210029, China. Electronic address:
Aim: Coronary artery disease (CAD) is a primary cause of mortality, prompting ongoing research into noninvasive diagnostic modalities. This study aimed to evaluate the diagnostic efficacy of exercise electrocardiography testing (EET) combined with cadmium zinc tellurium cardiac-dedicated single photon emission computed tomography (CZT-SPECT) imaging for CAD.
Materials And Methods: CZT-SPECT and EET were examined in 124 patients aged 20-85 years, followed by coronary angiography to evaluate the sensitivity, specificity, positive predictive value, and negative predictive value of EET/CZT-SPECT alone and in combination.
Brain Dev
December 2024
Division of Neurology, Saitama Children's Medical Center, 1-2 Chuo-ku Saitama-shi, Saitama 330-8777, Japan.
Purpose: This study aimed to elucidate the distribution of intracranial gamma-aminobutyric acid (GABA) receptors in patients with infantile epileptic spasms syndrome (IESS) of normal brain MRI findings using I-iomazenil single-photon emission computed tomography (IMZ-SPECT).
Methods: This retrospective study compared IMZ-SPECT images from 20 patients with IESS of unknown etiology with normal brain MRI (unknown IESS group) and 23 patients with developmentally normal epilepsy of the same age (developmentally normal group). A three-dimensional stereotactic region of interest (ROI) template was used to divide the brain into 24 segments (left and right callosomarginal, precentral, central, parietal, angular, temporal, posterior cerebral, pericallosal, lenticular nucleus, thalamus, hippocampus, and cerebellum), and the mean accumulation of I-iomazenil in each ROI was calculated.
Eur J Nucl Med Mol Imaging
December 2024
Department of Nuclear Medicine, Inselspital, Bern University Hospital, University of Bern, Freiburgstrasse 18, Bern, 3010, Switzerland.
Purpose: Long axial field-of-view (LAFOV) positron emission tomography/computed tomography (PET/CT) scanners enable high sensitivity and wide anatomical coverage. Therefore, they seem ideal to perform post-selective internal radiation therapy (SIRT) Y scans, which are needed, to confirm that the dose is delivered to the tumors and that healthy organs are spared. However, it is unclear to what extent the use of LAFOV PET is feasible and which dosimetry approaches results in accurate measurements.
View Article and Find Full Text PDFJ Control Release
December 2024
Department of Nuclear Medicine, Fudan University Shanghai Cancer Center, Shanghai 200032, China; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China; Center for Biomedical Imaging, Fudan University, Shanghai 200032, China; Shanghai Engineering Research Center of Molecular Imaging Probes, Shanghai 200032, China; Key Laboratory of Nuclear Physics and Ion-beam Application (MOE), Fudan University, Shanghai 200433, China. Electronic address:
Transarterial radioembolization (TARE) is a recommended locoregional strategy for intermediate hepatocellular carcinoma (HCC), whereas, the effect is insufficient to reverse the immunosuppression tumor microenvironment, and the overall benefits for patients remain to be improved. In this study, a multifunctional microsphere (MS) I-ICT/R848-MS is developed to propose an approach combined with TARE, icaritin (ICT) and immune modulator resiquimod (R848). ICT and iodine-131 (I) radiation can induce immunogenic cell death, which, in combination with R848, will boost dendritic cell (DC) maturation.
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