The Application Value Of Double Contrast Enhanced Ultrasonography In The Preoperative Staging And Microcirculation Perfusion Of Gastric Cancer

Objective: In this study,the double contrast-enhanced ultrasonography(DCEUS),in which an oral ultrasonic contrast agent(OCUS)is combined with an intravenous contrast agent,was used to assess the preoperative staging and microcirculation perfusion characteristics of gastric carcinoma.Methods: Prospective analysis of 70 patients with gastric carcinoma confirmed by gastroscope biopsy.All patients underwent preoperative oral ultrasonic contrast agent and double contrast-enhanced ultrasonography examination,57 cases of gastric cancer completed of surgical treatment and 13 cases of liver metastasis with gastric cancer were enrolled in this study.Compared with oral ultrasonic contrast agent,double contrast-enhanced ultrasonography and clinical pathology results to reflect infiltrating depth and liver metastasis and the application value of double contrast-enhanced ultrasonography of gastric cancer.The arrival time(AT),time to peak(TTP),infusion time(IT),baseline intensity(BI),peak intensity(PI)and enhanced intensity(EI)were calculated using the time-intensity curve(TIC),showing the tumor microcirculation perfusion characteristics by compared the gastric cancer tissue and normal gastric wall by tracing the region of interest.Results:The accuracy for assessing the T stage of gastric cancer was 71.92 % by OCUS and 87.71 % by DCEUS;The consistent with the pathological results of the kappa value is 0.640 by OCUS,0.849 by DCEUS(P<0.001);The preoperative diagnosis of gastric cancer staging accuracy rate by OCUS was significantly lower than that of DCEUS(?2=4.412,P=0.036);There were good intra-observer reliability of DCEUS for assessing T stage of gastric carcinoma.A total of52 lesions were found in 13 patients with liver metastases;The detect rate for liver metastasis by DCEUS(86.54%)was higher than that by OCUS(51.92%)significantly(?2=14.625,P<0.001).By compared the parameters of DCEUS between gastric cancer tissue and normal gastric wall,significant differences were obtained for peak intensity(PI)and enhanced intensity(EI)(P<0.001,P<0.001),PI and EI in gastric cancer tissue were higher than those in normal gastric wall;However the differences of basic intensity(BI),arrival time(AT),time to peak(TTP)and wash-in time(WIT)between two kinds of tissues were not significant(P value were 0.087,0.316,0.261,0.524),According to the ROC curve,the optimal threshold values of PI and EI were 22.79 dB and 18.55 dB in the identification of tumor boundaries.Conclusion: To obtain the double information of the lesion anatomy structure and microcirculation perfusion,the diagnosis of infiltration and liver metastases of gastric carcinoma by double contrast ultrasound has a high consistency with the postoperative pathology.DCEUS is promised to be a novel method to assess the preoperative gastric cancer noninvasive,safely,effectively,and reliably.