RESUMEN
BACKGROUND AND AIMS: Post-cholecystectomy biliary strictures can be treated surgically or nonsurgically. Although endoscopic or percutaneous treatments are the preferred approaches, these methods are not feasible in cases in which complete stricture occlusion prevents the successful passage of a guidewire. The utility of magnetic compression anastomosis (MCA) in patients with post-cholecystectomy complete biliary obstruction that cannot be treated conventionally was evaluated. METHODS: MCA was performed in 10 patients with post-cholecystectomy biliary strictures that did not resolve with conventional endoscopic or percutaneous treatment. One magnet was delivered through the percutaneous transhepatic biliary drainage tract, and another was advanced via ERCP of the common bile duct. After magnet approximation and recanalization, a fully covered self-expandable metal stent (FCSEMS) was placed for 3 months and then replaced for an additional 3 months. Stricture resolution was evaluated after FCSEMS removal. RESULTS: Among the 10 patients who underwent MCA for post-cholecystectomy biliary stricture, the biliary injury was Strasberg type B in 2, type C in 3, and type E in 5. Recanalization was successful in all patients (technical success rate, 100%). The mean follow-up period after recanalization was 50.2 months (range, 13.2-116.8 months). Partial restenosis after MCA occurred in 2 patients at 24.1 and 1.6 months after stent removal. ERCP with FCSEMS placement resolved the recurrent stenosis in both patients. CONCLUSIONS: MCA is a useful nonsurgical alternative treatment for complete biliary obstruction after cholecystectomy that cannot be resolved by use of conventional methods.
RESUMEN
Lacking of available water quality data causes the limited understanding of the coupled dynamics of hydrologic and nutrient cycles in lakes and reservoirs and along river streams. This study conducts the rotated Principal Component Analysis (rPCA) of water volume and total organic carbon (TOC) concentration data from â¼2200 agricultural reservoirs in South Korea to extract the major modes of their spatiotemporal variability. Over 2020-2022, the total TOC load in the reservoirs ranges between 1,165 and 1,492 tons (289 and 360 Mtons of water storage volume; 3.54 and 4.60 mg/L of TOC concentration). The first rPCA mode is assoicated with a decreasing trend of water level (38 % of the explained variance) and increasing trend of TOC concentration (27 %) over the southern Korea region, where the TOC concentration increased during the 2022 drought. The second rPCA mode is associated with interannual variability of water level (25 %) and TOC concentration (18 %) over the central Korea region. This study found a marginal relationship between paddy field area and TOC concentration and their regime shift to high TOC concentration during the 2022 drought, which was a potential cause of the increased TOC concentration in 2022. This study provided observational evidence of interactions between water volume and TOC concentration during a severe drought, suggesting a possible shift of the role of agricultural reservoirs to carbon source.