结合模型迭代重建的低剂量CT术前评估乳腺癌

Low dose CT with iterative model reconstruction technique in preoperative evaluation of breast cancer

目的以磁共振(magnetic resonance imaging,MRI)为对照,探讨低剂量CT乳腺动态成像结合模型迭代重建技术对乳腺癌术前乳腺病灶评估的可行性。方法 21例乳腺癌患者术前行乳腺CT、MRI检查,CT检查包括乳腺动态增强和胸部扫描,并结合模型迭代技术。在CT、MRI图像上分别记录乳腺病灶的数量、位置和最大直径;并分别根据CT的时间-密度曲线和MRI的时间-信号强度曲线,对乳腺病变的强化分型。结果CT有效辐射剂量为(2.15±0.39)m Sv。CT和MRI所检出乳腺病灶数量和位置完全一致,测量的病灶最大直径一致性良好(r=0.99,n=24,P<0.000 1)。CT与MRI测得病灶强化类型一致性良好(Kappa值为0.936,P<0.001)。结论结合模型迭代重建技术的动态乳腺CT在用于术前乳腺癌评估时,与MRI乳腺成像一致性良好。

Objective To investigate the feasibility of low dose computed tomography （CT） with iterative model reconstruction （IMR） technique compared with magnetic resonance imaging MRI in preoperative evaluation of breast cancer. Methods Dedicated CT and MRI were performed in 21 patients with diagnosed breast cancer for preoperative evaluation. A dedicated protocol combined with chest diagnostic CT and dynamic scans of breast was developed with the use of IMR technique. The number, site and the maximum diameter of breast lesion were recorded respectively in CT and MRI images. The enhancement patterns of breast lesion were classified according to time intensity curve derived from CT and time signal curve derived from MRI respectively. Results The effective radiation dose of dedicated breast CT was （2.15±0.39） mSv. Results of lesion number and lesion site obtained by CT and MRI was consistent. CT showed an excellent correlation with MRI for lesion maximum diameter （ r =0.99, n =24, P 〈 0.000 1 ）. Good agreement was observed between CT and MRI for lesion enhancement patterns （kappa value = 0.936, P 〈0.001）. Conclusion Dynamic breast CT with IMR technique has good agreement with MRI in preoperative evaluation of breast cancer.