Study on the Application Technique of Multi-slice Spiral CT Perfusion in of Thyroid Diseases

Objective To investigate the technique of Multi-slice Spiral CT perfusion with body tumor software package and evaluate the diagnosis value of its application of thyroid disease.Methods The multi-slice dynamic CT perfusion series was performed for thyroid perfusion with cine mode (1 s per rotation) onamulti-slice CT scanner (Siemens Somatom Sensation 40),40×0.6mm collination,120kV,60 mA Contrast injection was done by using 50 mlnonionic contrast agent (300 mgI/ml),at a flow rate of 3 ml/s with a power injector and 8 seconds delay,and data acquisition lasted for 55 seconds. The parameters of CT perfusion such as blood flow(BF),mean transit time(MTT),and permeability surface(PS)were measured and statistically analyzed in patients with thyroid carcinoma(n=16),and benign thyroid disease(n=35) including thyroid adenoma in 15 cases and nldule goiter in 20 cases proven by pathology, respectively, on a siemens-mmwp workstation using Perfusion 2 software package (siemens)with deconvolution method.ResultsThe images of perfusion with multi-slice CT could be readily obtained. Perfusion images can cleraly and directly display tumor diameter and outlines and quantitatively monitor blood perfusion status of tumor inner structures. The mean BF,BV,MTT and PS.The mean BF,BV,MTT, and PS in thyroid carcinoma were (324.81±218.96)ml/(100 g·min)、(7.69±5.03)ml/100 g、(3.87±2.52)s、(51.27±21.88)ml/(100 g·min),respectively .The mean BF,BV,MTT,and PS in benign group were (311.42±238.01)ml/(100 g·min)、(7.19±4.86)ml/100 g、(3.99±2.77)s、(40.24±23.49)ml/(100 g·min),respectively.The mean PS between two groups had significant difference(P0.05).However,the mean BF、BV and MTT were not statistically significant (P0.05). When PS≥50 ml/(100 g·min) was set as a diagnostic thershold, the sensitivity,specificity,accuracy,positive predictive value and negative predictive value were 72.1%,60.8%,69.1%,81.2%and 51.0%.Conclusion Perfusion MSCT is valuable for the differentiation of benignancy from malignancy in thyroid.