In:
EJNMMI Physics, Springer Science and Business Media LLC, Vol. 8, No. 1 ( 2021-12)
Kurzfassung:
99m Tc-PYP scintigraphy provides differential diagnosis of ATTR cardiomyopathy (ATTR-CM) from light chain cardiac amyloidosis and other myocardial disorders without biopsy. This study was aimed to assess the diagnostic feasibility and the operator reproducibility of 99m Tc-PYP quantitative SPECT. Method Thirty-seven consecutive patients who underwent a 99m Tc-PYP thorax planar scan followed by SPECT and CT scans to diagnose suspected ATTR-CM were enrolled. For the quantitative SPECT, phantom studies were initially performed to determine the image conversion factor (ICF) and partial volume correction (PVC) factor to recover 99m Tc-PYP activity concentration in the myocardium for calculating the standardized uptake value (SUV) (unit: g/ml). SUV max was compared among groups of ATTR-CM, AL cardiac amyloidosis, and other pathogens (others) and among categories of Perugini visual scores (grades 0–3). The intra- and inter-operator reproducibility of quantitative SPECT was verified, and the corresponded repeatability coefficient (RPC) was calculated. Results The ICF was 79,327 Bq/ml to convert count rate in pixel to 99m Tc activity concentration. PVC factor as a function of the measured activity concentration ratio in the myocardium and blood-pool was [ y = 1.424 × (1 − exp(− 0.759 × x )) + 0.104]. SUV max of ATTR-CM (7.50 ± 2.68) was significantly higher than those of AL (1.96 ± 0.35) and others (2.00 ± 0.74) (all p 〈 0.05). SUV max of grade 3 (8.95 ± 1.89) and grade 2 (4.71 ± 0.23) were also significantly higher than those of grade 1 (1.92 ± 0.31) and grade 0 (1.59 ± 0.39) (all p 〈 0.05). Correlation coefficient ( R 2 ) of SUV max reached 0.966 to 0.978 with only small systematic difference (intra = − 0.14; inter = − 0.23) between two repeated measurements. Intra- and inter-operator RPCs were 0.688 and 0.877. Conclusions 99m Tc-PYP quantitative SPECT integrated with adjustable PVC factors is feasible to quantitatively and objectively assess the burden of cardiac amyloidosis for diagnosis of ATTR-CM.
Materialart:
Online-Ressource
ISSN:
2197-7364
DOI:
10.1186/s40658-020-00342-7
Sprache:
Englisch
Verlag:
Springer Science and Business Media LLC
Publikationsdatum:
2021
ZDB Id:
2768912-8
