Image Quality of Low Dose Computed Tomography Combined with Iterative Model Reconstruction Technique in Preoperative Evaluation of Breast Cancer / 中国医学影像学杂志

ABSTRACT

Purpose To investigate the value of low dose CT combined with iterative model reconstruction (IMR) technique for evaluation of both breast lesion and pulmonary metastasis in patients with breast cancer,and compare the effects of IMR,hybrid iterative reconstruction (HIR) and filtered back projection (FBP) techniques on image quality.Materials and Methods Twenty-one patients with solitary tumor confirmed by mammography and/or ultrasonography at Navy General Hospital from January to May in 2016 were enrolled,and the related breast imaging reporting and data system reached to level 4 and above.All patients underwent dynamic contrast-enhanced CT with different tube current for breast (scanning 6 times within 6 minutes) and chest scans;the conventional tube current (61 mAs) was used at the 2 minutes phase after injection,and the low tube current (10 mAs) was used at the other 5 phases.CT images were reconstructed with FBP,HIR and IMR techniques,respectively.The images of breast lesions and chest in 2 minutes scans were evaluated objectively and subjectively.Results The mean effective radiation dose was (2.15 ± 0.39) mSv.The images of 3 reconstruction techniques at the 2 minutes phase were compared,and the IMR images showed the lowest image noise and the optimal contrast to noise ratio (P＜0.05).The images quality of 3 kinds of reconstruction techniques was acceptable,of which IMR was better than HIR and FBP (P＜0.05).Conclusion Low dose CT scan combined with IMR technique can remain low radiation with dose of 2 mSv,while maintaining good image quality,which can be used for preoperative evaluation of both breast lesion and pulmonary metastasis in patients with breast cancer.