Acute median arcuate ligament syndrome after pancreaticoduodenectomy

Abstract Background Median arcuate ligament syndrome (MALS) can cause severe complications after pancreaticoduodenectomy (PD). Most of the reported cases of MALS have been diagnosed perioperatively and can be treated efficiently by interventional radiology or division of the median acute ligament (MAL) fibers. Case report A 69-year-old woman underwent PD with resection of the SMV for pancreatic head cancer. Intraoperative exploration showed normal anatomy of the celiac trunk. Intraoperative digital palpation revealed normal pulsation of the common hepatic artery after resection of the gastroduodenal artery. On postoperative day (POD) 3, her liver function tests were abnormal, and bloody fluids were found in the drain. Abdominal CT showed necrosis of the pancreatic body and ischemia in the liver secondary to MALS which was not detected in the preoperative CT. Interventional radiology was tried first but failed. Division of the MAL fibers markedly increased the blood flow in the hepatic artery. Resection of the remnant pancreas and spleen was also performed simultaneously. Abdominal CT on POD 20 showed re-occlusion of the celiac artery. She experienced rupture of the gastrojejunostomy site, severe hepatic cytolysis, and choledochojejunostomy stricture thereafter. Conclusions This is the third case of MALS that has developed acutely after PD. MALS can cause refractory complications even after MAL release

Characterisation of structural similarities of precipitates in Mg–Zn and Al–Zn–Mg alloys systems

High angle annular dark field scanning transmission electron microscopy has been employed to observe precipitate structures in Al–Zn–Mg and Mg–Zn alloys. h1 precipitate structures in Al–Zn–Mg are commonly formed by MgZn2 Penrose bricks, but also frequently observed to incorporate Mg6Zn7 elongated hexagons via two different modes. Tilings of MgZn2 and Mg6Zn7 building blocks in both Beta′ 1 inMg–Zn and eta1 in Al–Zn–Mg alloys, create overall patterns which deviate from the chemical and structural configuration of solely monoclinic Mg4Zn7 or MgZn2 unit cells. Precipitate morphologies were found to be correlated to their internal sub-unit cell arrangements, especially to Mg6Zn7 elongated hexagons. Systematic or random arrangements of Mg6Zn7 elongated hexagons inside precipitates and therefore compositional and structural patterns, were found to be strongly related to the aspect ratio of the precipitates and altering of the precipitate/ matrix interface