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Medial genicular neurovascular anatomy and its role in precision of ultrasound-guided nerve blockade in end-stage knee osteoarthritis
No full textThe incidence of early recurrent venous thromboembolism : a systematic review and meta-analysis
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Diet and stones : associations from a large, population-representative study of urolithiasis and renal colic-like pain symptoms in Poland
No full textSCORE2 and derived model based on traditional risk factors in predicting cardiovascular disease mortality. 18 years follow-up of the Polish cohort participating in the HAPIEE Study
No full textIn vivo voxel-wise positronium lifetime imaging of thyroid cancer using clinically routine I-124 PET/CT
No full textPurpose: Measuring the lifetime of orthopositronium (oPs) has emerged as a promising approach for assessing tumor microenvironment characteristics, leveraging the susceptibility of oPs lifetime to local molecular factors. This study investigates the feasibility of voxel-wise oPs lifetime measurements in patients with thyroid cancer using a commercial long axial field-of-view (LAFOV) PET/CT scanner. Methods: Three patients with thyroid cancer underwent two PET/CT scans at 2 and 26 h post-administration [I]NaI, which included a 30 min scan in singles mode that allows to identify three-photon events. For regions with high I uptake, we determined the lifetime of oPs through a Bayesian fit for a voxel-based (with a voxel size of 7 × 7 × 7 mm), lesion-based and organ-based analysis. Results: The oPs lifetime of the voxel with the highest count statistics and activity concentration of 108.1 kBq mL is 1.77 ± 0.26 ns. The visualization of the oPs lifetimes inside a lesion was feasible, though it remains affected by statistical uncertainty. On a per-lesion basis, the lifetime could be measured (exemplary lesion:1.90 ± 0.17 ns) with mean activity concentrations ranging from 9.5 to 34.1 kBq mL and volumes of 1.31 to 6.27 mL. The positronium lifetime measurement error shows a slight correlation (r = 0.48 with BF = 7.88) with activity concentration of the regarded region. Besides lesions, the positronium lifetime could also be determined in several organs. Conclusion: This is the first report of human in-vivo measurement of oPs lifetime with [I]NaI using a commercial LAFOV PET/CT scanner. The voxel-wise oPs lifetime imaging is feasible, though with a high statistical uncertainty. Lesion-based measurements can yield satisfactory statistical precision even for small volumes
