摘要
Purpose: Since HCC lesions are generally characterized by lower Hounsfield unit value (HU) values and higher tracer uptake (SUV or Standardized Uptake Values), we intended to determine if normalizing the SUV by the HU, for the lesion and normal liver would improve sensitivity and specificity. Material and Methods: Twenty-three consecutive patients with HCC diagnosed clinically or pathologically underwent C11-Acetate (C11-A) and F18-FDG (FDG) PET/CT imaging before surgery during a 424-day interval. After exclusion of treated or calcified lesions, 44 lesions are included in this study. The original metrics are the maximum SUV (SUVmax) and maximum or average HU (HUmax or HUmean) for lesions and normal liver. For the normal liver, an average SUV (SUVmean) was included. The derived values are the ratios of SUV/HU values. The efficacy is the fraction of outcomes of non-overlapping metrics between lesion and normal liver. Results: For FDG the efficacy is 0.489 for the lesions SUVmax versus normal liver SUVmax. For lesion SUVmax/HUmean versus normal liver SUVmax/HUmax, the efficacy is 1.00. For C11-A the corresponding values are 0.045 and 0.920. Conclusion: Normalizing SUV values for changes in HU values increases the contrast between normal liver and lesions. Analytical fusion can be very effective.
Purpose: Since HCC lesions are generally characterized by lower Hounsfield unit value (HU) values and higher tracer uptake (SUV or Standardized Uptake Values), we intended to determine if normalizing the SUV by the HU, for the lesion and normal liver would improve sensitivity and specificity. Material and Methods: Twenty-three consecutive patients with HCC diagnosed clinically or pathologically underwent C11-Acetate (C11-A) and F18-FDG (FDG) PET/CT imaging before surgery during a 424-day interval. After exclusion of treated or calcified lesions, 44 lesions are included in this study. The original metrics are the maximum SUV (SUVmax) and maximum or average HU (HUmax or HUmean) for lesions and normal liver. For the normal liver, an average SUV (SUVmean) was included. The derived values are the ratios of SUV/HU values. The efficacy is the fraction of outcomes of non-overlapping metrics between lesion and normal liver. Results: For FDG the efficacy is 0.489 for the lesions SUVmax versus normal liver SUVmax. For lesion SUVmax/HUmean versus normal liver SUVmax/HUmax, the efficacy is 1.00. For C11-A the corresponding values are 0.045 and 0.920. Conclusion: Normalizing SUV values for changes in HU values increases the contrast between normal liver and lesions. Analytical fusion can be very effective.