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April 15-16, 2019 | Frankfurt, Germany
Applied Physics & Laser, Optics and Photonics
International Conference on
Materials Science and Nanotechnology | Volume: 3
Evaluation impact count recovery model on standardized uptake value used in PET-CT
Hamed Farag
and
Ahmed Abdel Mohymen
Cairo University, Egypt
E
valuation of effect of lesion size and sphere to
background ratio (SBR) on the threshold used
for PET tumor volume delineation.
Evaluation effect and accuracy of recovery
coefficient (RC) model on standards uptake value
(SUV) of different inner size diameters filled with
different activity concentration and apply this
model on small cohort of patients and construct
Look Up Table (LUT) for different lesions with
different sizes. A cylindrical phantomequipped with
different volume hollow spheres was used. Two
different reconstruction algorithms were applied in
this study; one of them modified with Point Spread
Function (the other did not base on PSF).
Partial volume effect (PVE) was highly dominant in
low uptake spheres although it had large size, i.e.,
not only small size object affecting by PVE but also
low activity concentration object. For true volume
measurements, practically TrueX algorithm was
more accurate when activity measurements dal
with true measured volumes.
Also, the results showed using that phantom
study had successfully provided “Look Up Table”
for the partial volume correction of spherical
lesions at maximum measured activity ratios that
were typically noted in human PET-CT imaging.
The present study demonstrated that SBR
have not significant effect on the estimation of
volumes from PET images in the different SBRs.
The only determining factor for the threshold for
PET volume estimation was the size of the sphere.
Superior percent accuracy was shown for OSEM
algorithm when applying RC model to corrected
SUV values and OSEM was more efficient and less
error variation with respect to sphere volume,
but in case of uncorrected data, no remarkable
difference between TrueX and OSEM algorithm
had been observed.
e
:
hamedfarag103@hotmail.com