Dataset Information

Impact of point-spread function reconstruction on dynamic and static 18F-DOPA PET/CT quantitative parameters in glioma

ABSTRACT:

Background

Quantification of dynamic and static parameters extracted from 3,4-dihydroxy-6-[18F]-fluoro-L-phenylalanine (18F-DOPA, FDOPA) positron emission tomography (PET)/computed tomography (CT) plays a critical role for glioma assessment. The objective of the present study was to investigate the impact of point-spread function (PSF) reconstruction on these quantitative parameters.

Methods

Fourteen patients with untreated gliomas and investigated with FDOPA PET/CT were analyzed. The distribution of the 14 cases was as follows: 6 astrocytomas-isocitrate dehydrogenase-mutant; 2 oligodendrogliomas/1p19q-codeleted-isocitrate dehydrogenase-mutant; and 6 isocitrate dehydrogenase-wild-type glioblastomas. A 0–20-min dynamic images (8×15, 2×30, 2×60, and 3×300 s post-injection) and a 0–20-min static image were reconstructed with and without PSF. Tumoral volumes-of-interest were generated on all of the PET series and the background volumes-of-interest were generated on the 0–20-min static image with and without PSF. Static parameters (SUVmax and SUVmean) of the tumoral and the background volumes-of-interest and kinetic parameters (K1 and k2) of the tumoral volumes-of-interest extracted from using full kinetic analysis were provided. PSF and non-PSF quantitative parameters values were compared.

Results

Thirty-three tumor volumes-of-interest and 14 background volumes-of-interest were analyzed. PSF images provided higher tumor SUVmax than non-PSF images for 23/33 VOIs [median SUVmax =3.0 (range, 1.4–10.2) with PSF vs. 2.7 (range, 1.4–9.1) without PSF; P<0.001] and higher tumor SUVmean for 13/33 volumes-of-interest [median SUVmean =2.0 (range, 0.8–7.6) with PSF vs. 2.0 (range, 0.8–7.4) without PSF; P=0.002]. K1 and k2 were significantly lower with PSF than without PSF [respectively median K1 =0.077 mL/ccm/min (range, 0.043–0.445 mL/ccm/min) with PSF vs. 0.101 mL/ccm/min (range, 0.055–0.578 mL/ccm/min) without PSF; P<0.001 and median k2 =0.070 min–1 (range, 0.025–0.146 min–1) with PSF vs. 0.081 min–1 (range, 0.027–0.180 min–1) without PSF; P<0.001]. Background SUVmax and SUVmean were statistically unaffected [respectively median SUVmax =1.7 (range, 1.3–2.0) with PSF vs. 1.7 (range, 1.3–1.9) without PSF; P=0.346 and median SUVmean =1.5 (range, 1.0–1.8) with PSF vs. 1.5 (range, 1.0–1.7) without PSF; P=0.371].

Conclusions

The present study confirms that PSF significantly increases tumor activity concentrations measured on PET images. PSF algorithms for quantitative PET/CT analysis should be used with caution, especially for quantification of kinetic parameters.

SUBMITTER: Girard A

PROVIDER: S-EPMC8739156 | biostudies-literature |

REPOSITORIES: biostudies-literature

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