Based on a that study, we had generated a “Look Up Table” for seven different size of lesion only, namely 11, 13, 13.5, 14.4, 15, 18.3 and 19.3 mm having object to background ratio in the PET scan ranging from 2.70 to 19.60, as was seen in the phantom.
We had previously carried out a phantom study at our institute to evaluate the PVE introduced in spheres of a phantom and the RC values to be applied for partial volume corrected (PVC) of those spheres. This correction can be achieved by applying a particular factor called the recovery coefficient (RC). Therefore, small-sized lesions on PET-CT should be corrected for the error introduced by PVE.
#Excel trendline partial data full
The lesions smaller than twice or thrice of full width half maximum (FWHM) of PET scanner cannot display its true structural (true size) and functional properties (true counts) because of “partial volume effect” (PVE). For such lesions, if the characterization of a lesion is based on a SUV cut-off (suppose SUV max > 2.5), the results can be radically altered. However, assessment of SUV is erroneous in small lesions. SUV is also being employed for response monitoring and prognostication of wide array of tumors. It is used for categorizing malignant versus benign lesions, and a max SUV of 2.5 or greater is usually consistent with malignancy. Standardized uptake value (SUV) is the most widely used semi-quantitative parameter used in positron emission tomography-computed tomography (PET-CT).