Fedora-type magnetic compression anastomosis device for intestinal anastomosis

BACKGROUND Although previous studies have confirmed the feasibility of magnetic compression anastomosis(MCA),there is still a risk of long-term anastomotic stenosis.For traditional MCA devices,a large device is associated with great pressure,and eventually increased leakage.AIM To develop a novel MCA device to simultaneously meet the requirements of pressure and size.METHODS Traditional nummular MCA devices of all possible sizes were used to conduct ileac anastomosis in rats.The mean(±SD)circumference of the ileum was 13.34±0.12 mm.Based on short-and long-term follow-up results,we determined the appropriate pressure range and minimum size.Thereafter,we introduced a novel“fedora-type”MCA device,which entailed the use of a nummular magnet with a larger sheet metal.RESULTS With traditional MCA devices,the anastomoses experienced stenosis and even closure during the long-term follow-up when the anastomat was smaller thanΦ5 mm.However,the risk of leakage increased when it was larger thanΦ4 mm.On comparison of the different designs,it was found that the“fedora-type”MCA device should be composed of aΦ4-mm nummular magnet with aΦ6-mm sheet metal.CONCLUSION The diameter of the MCA device should be greater than 120%of the enteric diameter.The novel“fedora-type”MCA device controls the pressure and optimizes the size.

Characteristics of fecal microbial communities in patients with non-anastomotic biliary strictures after liver transplantation

AIM To explore the possible relationship between fecal microbial communities and non-anastomotic stricture(NAS) after liver transplantation(LT).METHODS A total of 30 subjects including 10 patients with NAS, 10 patients with no complications after LT, and 10 nonLT healthy individuals were enrolled. Fecal microbial communities were assessed by the 16 S r RNA gene sequencing technology.RESULTS Different from the uncomplicated and healthy groups, unbalanced fecal bacterium ratio existed in patients with NAS after LT. The results showed that NAS patients were associated with a decrease of Firmicutes and Bacteroidetes and an increase of Proteobacteria at the phylum level, with the proportion-ratio imbalance between potential pathogenic families including Enterococcaceae, Streptococcaceae, Enterobacteriaceae, Pseudomonadaceae and dominant families including Bacteroidaceae. CONCLUSION The compositional shifts of the increase of potential pathogenic bacteria as well as the decrease of dominant bacteria might contribute to the incidence of NAS.

Miniature magnetically anchored and controlled camera system for trocar-less laparoscopy

AIM To design a miniature magnetically anchored and controlled camera system to reduce the number of trocars which are required for laparoscopy.METHODS The system consists of a miniature magnetically anchored camera with a 30° downward angle, an external magnetically anchored unit, and a vision output device. The camera weighs 12 g, measures Φ10.5 mm × 55 mm and has two magnets, a vision model, a light source, and a metal hexagonal nut. To test the prototype, the camera was inserted through a 12-mm conventional trocar in an ex vivo real liver laparoscopic training system. A trocar-less laparoscopic cholecystectomy was performed 6 times using a 12-mm and a 5-mm conventional trocar. In addition, the same procedure was performed in four canine models.RESULTS Both procedures were successfully performed using only two conventional laparoscopic trocars. The cholecystectomy was completed without any major complication in 42 min(38-45 min) in vitro and in 50 min(45-53 min) using an animal model. This camera was anchored and controlled by an external unit magnetically anchored on the abdominal wall. The camera could generate excellent image. with no instrument collisions.CONCLUSION The camera system we designed provides excellent optics and can be easily maneuvered. The number of conventional trocars is reduced without adding technical difficulties.