Objective:To compare the accuracy of renal calyceal fornix puncture and complication between non-vascular contrast-enhanced ultrasound (NV CEUS) and conventional ultrasound guided in percutanous nephrolithotomy for nephrolithiasis patients with slight or no hydronephrosis.Methods:This randomized controlled trial was conducted in nephrolithiasis patients with slight or no hydronephrosis in our hospital from May 2018 to June 2019. The patients were randomized to receive NV CEUS or conventional ultrasound guided PCNL.Inclusion criteria: age 18-70 years old and nephrolithiasis patients with slight or no hydronephrosis. Exclusion criteria: pregnant women, functional solitary kidney, abnormal anatomy or high-risk of intestinal injury, acute urinary tract infection, coagulation dysfunction or taking drugs that affect blood coagulation, heart failure, severe arrhythmia or other high-risk diseases, abnormal renal function (SCR > 1.2-fold upper limit), or severe obesity (BMI>40 kg/m 2). Patients in both groups underwent anterorenal pyelography of renal fistula. Data of the study were recorded: the decrease in hemoglobin, the puncture time, the success rate of one needle puncture, the time of hospital stay, the stone for free, and postoperative renal fistula anterograde pyelography to confirm whether the puncture was performed through the calyces. Results:A total of 48 patients were enrolled, 24 patients in each group, the preoperative parameters were comparable between the two groups(all P>0.05). The puncture accuracy of calyces fornix in experimental group and control group was 87.50%(21/24) and 41.67%(10/24), respectively.The hemoglobin drop was 2.0(0.0, 12.0) and 14.0(7.0, 17.0) g/L, the puncture time was 40.0(28.5, 53.0) and 70.0 (55.5, 84.5) seconds, and the success rate of one needle puncture was 95.83%(23/24) and 75%(18/24). The differences between the two groups were statistically significant (all P<0.05). No blood transfusion, interventional embolization, septic shock and other serious infection complications were found in the two groups. Conclusions:For nephrolithiasis patients with slight or no hydronephrosis, NV CEUS guided can significantly improve the accuracy of calyx vault puncture, shorten the puncture time and reduce bleeding compared with conventional ultrasound guided PCNL.

The relationship of cause-result between low selenium (Se) and Kashin-Beck disease (KBD) was probed by the prospective study of epidemiological method with regarding low-Se as an exposure factor in this paper. 597 healthy children lived in KBD areas with low, middle and high prevalence were divided into the low-Se exposed group and the non-low-Se exposed group according to their Se content in hair. The low-Se exposed group was divided into three subgroups, such as Se content in hair≤110 ng/g, 110 ng/g＜Se content in hair≤150 ng/g and 150 ng/g＜Se content in hair≤200 ng/g, respectively. Six new cases of the total with KBD (incidence was 0.574% person-year) were found in the low-Se exposed group during three years period of the investigation. No new case was found in the non low-Se exposed group . KBD incidence was not significantly different between those two groups. Two new cases were found in children with Se content in hair kept below 110 ng/g during three years (incidence: 1.21% person-year). SMR in each group indicated that the new cases observed in the low-Se exposed group was remarkable lower than the new cases expected. It was not observed that the dose-response relationship between low-Se and KBD, and was not supported that the low-Se was a predominant factor to cause KBD.