Objective To investigate the role of double contrast-enhanced ultrasonography (DCUS) in the diagnosis of rectal gastrointestinal stromal tumors (GISTs). Methods In eleven patients with rectal GISTs before surgery, gastrointestinal ultrasound contrast agent were injected into rectal lumen and tumor’s two dimensional ultrasound features were analyzed. Microbubbles were injected into the vein to investigate the feature of lesion microcirculation perfusion. After the surgery, according to the tumor diameter and mitotic count, rectal GISTs were classified as very low-risk, low-risk, intermediated-risk and high-risk tumors. The very low-risk and low-risk tumors were grouped together as one group while the intermediated-risk and high-risk tumors were grouped together as another group. According to ultrasound performance and pathological type, ultrasonic features of rectal GISTs with different risk levels were estimated. Results Among all rectal GISTs cases, 63.6%(7/11) were low-risk. Under DCUS, the tumor diameter was less than 5 cm, with regular round, hypoechogenicity, uniform low enhancement and less internal liquefaction necrosis. For the 36.4%(4/11) high-risk cases, under DCUS, the tumor diameter was≥5 cm, with irregular round or lobulation, mixed hyperechogenicity and hypoechogenicity, nonuniform high enhancement, large blood vessel and common liquefied necrosis region. The biological behavior of rectal GISTs was relevant to lesion size, liquefaction necrosis and enhancement mode of ultrasound contrast and irrelevant to the bound and shape of lesion. The accuracy of DCUS and contrast-enhanced ultrasonography were 90.9%(10/11) and 72.7%(8/11) respectively. Conclusions DCUS is considered as an effective tool in diagnosingrectal GISTs and can get useful information of the biological characteristics. It has great value for the diagnosis and treatment of rectal GISTs.

Objective:To evaluate the clinical application value of gastrointestinal contrast-enhanced ultrasound combined gas injection method in verifying the location of nasointestinal tube in critically ill patients.Methods:Data of 60 critically ill patients who had the indications of indwelling nasointestinal tube were collected from September 1,2015 to September 1,2016 in the Intensive Care Unit of Zhejiang Provincial People(s) Hospital.The position of nasointestinal tube in patients who underwent bedside blind insertion would be confirmed routinely through gas injection auscultation method.After tube was inserted,its route was scanned by ultrasound with gas perfusion assistance.Afterwards,rapid gas perfusion was used until suspicious tube end position was determined.Furthermore,oral ultrasound contrast agent was injected into the tube if instantaneous strong echo of gas was observed in localized lumen,and contrast agent filling meant the placement being successful.Two methods of position confirmation of nasointestinal tube in critically ill patients included gastrointestinal contrast enhanced ultrasound combined gas injection and gas injection auscultation only,and the effect of the two methods was compared and confirmed by chest and abdominal X ray examinations to verify the location of nasointestinal tube below pylorus.Results:A total of 60 patients were included in this study,58 patients(96.7％)in gastrointestinal contrast enhanced ultrasound combined gas injection group were successfully positioned.Among them,the placements of tube in 56 cases were below pylorus,while 2 cases were above pylorus.The sensitivity,specificity,positive predictive value,negative predictive value and accuracy of location of gastrointestinal contrast enhanced ultrasound combined gas injection method were 96.6％,100％,100％,50％,96.7％ and of gas injection auscultation method were 74.1％,50％,97.7％,6.3％ and 73.3％.The differences of the sensitivity,specificity,negative predictive value and accuracy between the two methods were statistically significant (P ＜ 0.05).Conclusion:Gastrointestinal contrastenhanced ultrasound combined gas injection method is a safe,simple and convenient method with high sen-sitivity,specificity,negative predictive value and accuracy in confirming the location of the nasointestinal tube.

Objective:To observe the effects of applying ultrasound-guided balloon dilatation in the treatment of post-stroke cyclopthyroid achalasia.Methods:Thirty-eight stroke survivors with cyclopneaful achalasia were divided into a control group ( n=19) and an experimental group ( n=19). All had been diagnosed with cycloparyngeal achalasia using videofluoroscopic swallowing study (VFSS). The controls were treated with conventional oral balloon dilatation, while the experimental group underwent ultrasound-guided oral balloon dilatation. The treatment was performed once every 2 days. During the treatment period, the durations and the number of expansions were recorded, and the patient′s comfort and throat pain were evaluated. The Kubota drinking water test (KDWT), standardized swallowing assessment (SSA) scoring and VFSS scoring were compared before and after the 2 weeks of treatment. Results:The average daily duration of expansions in the experimental group was significantly less than in the control group and their number was significantly greater. Comfort and larynx pain were also significantly better in the experimental group. The effective rate in the KDWT was 78.95% in the treatment group, significantly higher than the control group′s 31.58%. Significant differences were also found in the average SSA scores, VFSS pharyngeal phase scores and in the incidence of achalasia between the experimental and control groups.Conclusions:Using ultrasound to guide balloon dilatation can shorten the operation, reduce the throat pain involved and allow for more expansions, greater comfort and thus more effective treatment.