Newly designed J-shaped tip guidewire: A preliminary feasibility study in wire-guided cannulation

AIM: To perform wire-guided cannulation using a newly designed J-shaped tip guidewire, and to verify feasibility and safety for use. METHODS: The study was conducted on endoscopic retrograde cholangiopancreatography (ERCP) patients with na ve papilla undergoing diagnosis and treatment of biliary diseases between September 2011 and July 2012. We performed ERCP in a succession of 50 cases with a J-shaped tip guidewire. The first insertion attempt began with a trainee who had 5 min to complete cannulation, followed if necessary by the trainer for another 5 min. We assessed the primary success rate of selective biliary cannulation within 10 min and adverse events such as post-ERCP pancreatitis (PEP), bleeding or perforation.RESULTS: The primary success rate was 90% (45/50) within 10 min, the initial success rate within 5 min by trainee staff was 76% (38/50). The rate of PEP was 6% (3/50), but all 3 cases were mild pancreatitis. All patients were managed successfully with conservative treatment. There was no bleeding or perforation. CONCLUSION: A newly designed J-shaped tip guidewire has the possibility to facilitate selective biliary cannulation for ERCP and appears to be safe.

0.025-inch vs 0.035-inch guide wires for wire-guided cannulation during endoscopic retrograde cholangio pancreatography:A randomized study

AIM:To compare the clinical outcomes between 0.025-inch and 0.035-inch guide wires(GWs) when used in wire-guided cannulation(WGC).METHODS:A single center,randomized study was conducted between April 2011 and March 2013. This study was approved by the Medical Ethics Committee at our hospital. Informed,written consent was obtained from each patient prior to study enrollment. Three hundred and twenty-two patients with a na?ve papilla of Vater who underwent endoscopic retrograde cholangiopancreatography(ERCP) for the purpose of selective bile duct cannulation with WGC were enrolled in this study. Fifty-three patients were excluded based on the exclusion criteria,and 269 patients were randomly allocated to two groups by a computer and analyzed:the 0.025-inch GW group(n = 109) and the 0.035-inch GW group(n = 160). The primary endpoint was the success rate of selective bile duct cannulation with WGC. Secondary endpoints were the success rates of the pancreatic GW technique and precutting,selective bile duct cannulation time,ERCP procedure time,the rate of pancreatic duct stent placement,the final success rate of selective bile duct cannulation,andthe incidence of post-ERCP pancreatitis(PEP).RESULTS:The primary success rates of selective bile duct cannulation with WGC were 80.7%(88/109) and 86.3%(138/160) for the 0.025-inch and the 0.035-inch groups,respectively(P = 0.226). There were no statistically significant differences in the success rates of selective bile duct cannulation using the pancreatic duct GW technique(46.7% vs 52.4% for the 0.025-inch and 0.035-inch groups,respectively; P = 0.884) or in the success rates of selective bile duct cannulation using precutting(66.7% vs 63.6% for the 0.025-inch and 0.035-inch groups,respectively; P = 0.893). The final success rates for selective bile duct cannulation using these procedures were 92.7%(101/109) and 97.5%(156/160) for the 0.025-inch and 0.035-inch groups,respectively(P = 0.113). There were no significant differences in selective bile duct cannulation time(median ± interquartile range:3.7 ± 13.9 min vs 4.0 ± 11.2 min for the 0.025-inch and 0.035-inch groups,respectively; P = 0.851),ERCP procedure time(median ± interquartile range:32 ± 29 min vs 30 ± 25 min for the 0.025-inch and 0.035-inch groups,respectively; P = 0.184) or in the rate of pancreatic duct stent placement(14.7% vs 15.6% for the 0.025-inch and 0.035-inch groups,respectively; P = 0.832). The incidence of PEP was 2.8%(3/109) and 2.5%(4/160) for the 0.025-inch and 0.035-inch groups,respectively(P = 0.793).CONCLUSION:The thickness of the GW for WGC does not appear to affect either the success rate of selective bile duct cannulation or the incidence of PEP.

Wideband acoustic source localization using multiple spherical arrays : anangular-spectrum smoothing approach

A novel algorithm using multiple spherical arrays based on spherical harmonic analysis is proposed to localize wideband acoustic sources. In the novel spherical harmonic algorithm, the re- ceived microphone signals are firstly used to do the spherical Fourier transformation. Then, the mul- tiple signal classification （MUSIC） algorithm is applied to the spherical components to obtain the an- gular-spectrum. Finally, the angular-spectrum smoothing technique is proposed to obtain the accu- rate localization of wideband sources. In contrast to the traditional single spherical array, the multi- pie spherical arrays used in this paper consist of several randomly distributed spheres in a given plane. The microphones are uniformly placed on each sphere, the same as the usual single spherical array. Simulation comparison of wideband sources localization between a single spherical array and multiple spherical arrays based on the novel algorithm is carried out to validate our proposed meth- od.