토끼 VX2종양의 MR/PET영상을 동시 촬영했을 때와 분리 촬영했을 때의 Ktrans 와 K1 관계 비교 연구

Abstract

Introduction: The purpose of this experimental study was to compare the relationship of Ktrans from DCE-MRI and K1 from dynamic 13N-NH3-PET between simultaneous and separate MR/PET acquisition in the VX2 rabbit carcinoma model. Methods: Eight rabbits underwent MR/PET examination simultaneously and separately, 14 and 15 days after VX2 tumor implantation at the left paravertebral muscle. The Ktrans and K1 values were estimated using an in-house software program. The relationships between Ktrans and K1 were analyzed using Pearsons correlation coefficients and linear/nonlinear regression function. Results: This study finally included five rabbits. Assuming a linear relationship, Ktrans and K1 exhibited moderate positive correlations with both simultaneous (r = 0.54–0.57) and separate (r = 0.53–0.69) imaging. However, while the Ktrans and K1 from separate imaging were linearly correlated, those from simultaneous imaging exhibited a nonlinear relationship. The amount of change in K1 associated with a unit increase in Ktrans varied depending on Ktrans values. Conclusions: The relationship between Ktrans and K1 was different between simultaneous and separate MR/PET acquisition. The relationship between Ktrans and K1 may be mis-interpreted with separate MR and PET acquisition.