The creation of functioning gastrojejunostomy following magnetic compression

Background Magnetic compression for creating gastrojejunostomy has many advantages according to previous studies. However, following mechanical device release after healing, the anastomotic stenosis becomes the pivotal point. Methods Rectangle-shaped magnets were used for magnetic compression in rabbits. Both paclitaxel-loaded magnets and a strategy of pyloric ligation were chosen to improve the gastrojejunostomy. Based on these choices, the half-capsule was applied to occlude the pylorus after anastomotic formation. The size and patency of the anastomoses were analyzed to evaluate the efficacy of these approaches. A histological examination was also performed. Results The positive effect of ligating the pylorus on gastrojejunostomy was significantly greater than that achieved using paclitaxel-loaded magnets during either short- or long-term follow-up. There were fewer scar tissue and collagen fibers at the anastomotic site in the treatment group than in the control group. The anastomotic aperture was of great interest at 9 months after the ligation of the pylorus following magnetic compression. In the view of the jejunum, although the aperture was barely visible, gastric juice was continuously spilling through it like a spring, and the aperture was clearly visible from the stomach side. All half-capsules failed to block the pylorus. Conclusion The effect of paclitaxel on maintaining gastrojejunostomy patency was temporary. The ligation of the pylorus ensured the long-term patency of gastrojejunostomy, and the aperture was comparable to the pylorus which could play an anti-reflux role. Further studies for the sort of gastrointestinal aperture are being planned.

after anastomotic formation. The size and patency of the anastomoses were 23 analyzed to evaluate the efficacy of these approaches. A histological 24 examination was also performed. Results: The positive effect of ligating 25 the pylorus on gastrojejunostomy was significantly greater than that 26 achieved using paclitaxel-loaded magnets during either short-or long-term 27 follow-up. There were fewer scar tissue and collagen fibers at the 28 anastomotic site in the treatment group than in the control group. The 29 anastomotic aperture was of great interest at 9 months after the ligation of 30 the pylorus following magnetic compression. In the view of the jejunum, 31 although the aperture was barely visible, gastric juice was continuously 32 spilling through it like a spring, and the aperture was clearly visible from 33 the stomach side. All half-capsules failed to block the pylorus. Conclusion: 34 The effect of paclitaxel on maintaining gastrojejunostomy patency was  The magnets maintain a permanent pressure at the anastomotic point 57 until their release and improve the performance of circumferential 58 airtightness so that anastomotic fistulas and bleeding can be avoided in the 59 early stage. Following mechanical device release after healing, however,    Before the experiment, the rabbits were adaptively fed for one week.

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The animals were randomly divided into 5 groups: the initial diameter  to their cages and allowed free access to food and water. 125 An abdominal X-ray was taken immediately to mark the initial 126 position of the magnet device as the base level, and this data was used to 127 confirm whether the device became unexpectedly separated or fell off the 128 anastomotic stoma during the experimental period.

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In the test of MCA-HC, all three half-capsules failed to act as expected 153 to block the pylorus, and they were extruded from the pylorus before the 154 magnet devices released (Fig 1). These rabbits were randomly transferred 155 into the group of measuring initial diameter, the control group, or the 156 MCA-LP group, respectively.   (Fig 2A), and the calculated area was 19.6 mm 2 , which was not 166 in accordance with the expected value of 80 mm 2 given a relative 167 contraction of 75.5%.

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The anastomotic diameter was reduced to 2.2 ± 0.2 mm at 50 days after 169 the MCA procedure (P < 0.01, vs. the initial diameter; Fig 2B). In the 170 present study, a diameter of 7.1 ± 0.2 mm was measured at 50 days after 171 the operation in the MCA-PTX group (P < 0.01 vs. control group; Fig 2C), 172 while the diameter was 8.5 ± 0.4 mm in the MCA-LP group (P < 0.01 vs. 173 control group; P < 0.01 vs. MCA-PTX group; Fig 2D).  Fig 3). The aperture of anastomosis was of great 181 interest at 9 months after the procedure in the MCA-LP group. On the 182 outside view, the side-to-side anastomoses between the stomach and 183 jejunum were complete (Fig 3A). In a window sectioning the jejunum, 184 although the aperture was barely visible, gastric juice was continuously 185 spilling through it like a mountain spring (Fig 3B), and the aperture was 186 clearly visible from the stomach side (Fig 3C). The gastrojejunostomy was 11 187 covered by mucosa with fibrosis in the submucosal and muscular layers.

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There was less scar tissue and fewer collagen fibers at the anastomotic site 189 in the experimental group than in the control group (Fig 4).  The magnets firmly attracted to each other with no accidental 210 separation. The compression force applied by the paired magnets was 9.1 211 ± 0.4 N, and the associated pressure was 11.4 ± 0.5 N/cm 2 with no spacing.

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Considering the thickness of the interposed tissue, the force was 4.4 ± 0.9 213 N with an associated pressure of 5.6 ± 1.0 N/cm 2 according to the distance beneficial until creating a stenosis. In traditional approaches, the scar 231 gradually forms during the inflammation phase, approximately one month 232 after the operation [13]. In this study, the first observation date was set at 233 the 50 days after the operation. In the control group, the aperture had 234 contracted to less than one-half of its original diameter. In the previous 235 study that used smaller magnets (7.2×3.5×2.0 mm), the initial diameter of 236 gastrojejunostomy was 1.5 mm, and the gastrojejunostomy was completely 237 closed within 12 days (Qiao W, unpublished data). The primary size of the 238 anastomosis is related to its permanent patency.

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The local administration of drugs such as paclitaxel-loaded magnets, 240 can improve the patency of the anastomotic stoma in the early stage, but its