Gallbladder torsion is a rare, acute abdominal disease. It was first reported by Wendell in 1898. Since then, only 500 cases have been reported. Gallbladder torsion occurs in all age groups, although it usually appears in the latter stages of life. The occurrence ratio between women and men is 3:1. Most cases are diagnosed during surgery. The main treatment is surgical detorsion and cholecystectomy. Despite progress in radiologic imaging diagnosis, it is not easy to obtain a precise preoperative diagnosis of gallbladder torsion. In previous reports, only 9.8% of all gallbladder torsion cases were diagnosed preoperatively. We present a case of acute body-neck gallbladder torsion in an elderly man, and we review the radiologic findings of magnetic resonance imaging, computed tomography, and ultrasonography. The radiologic findings in the present case were helpful in obtaining a preoperative diagnosis of gallbladder torsion. The diagnosis was confirmed by T2-weighted magnetic resonance images, which showed an intra-gallbladder segment located between the body and neck of the gallbladder, with a notable crease within this segment.

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SUMMARYWireless sensor nodes may be spread over large areas and long distances, and require multi-hop communications between nodes, making direct management numerous wireless sensor nodes inefficient. Hierarchical management can be adopted to control several nodes. Effectively controlling the top-level nodes can decrease the costs of managing nodes and of the communication among them. The lower-level nodes are controlled and organized with the higher-level nodes. This study presents an algorithm for self-organization mechanism of higher-level nodes, contesting member nodes by multi-hop to form hierarchical clusters, and applying the '20/80 rule' to determine the ratio of headers to member nodes. Furthermore, the broadcast tree is constructed with the minimum number of hops. Simulation results indicate that the mechanism has a 6-22% lower cover loss than other approaches. The average delay of the minimum hop count approach is 0.22-1.57 ms less than that of free hop count approach. The simulation also reveals the influence of 20/80 rule on cluster formation between sensor nodes.

Internal abdominal herniations are rare. A 34-year-old healthy man was seen in the emergency room because of severe lower abdominal pain and episodic vomiting. Pericecal internal herniation of the inferior ileocecal recess was suspected by abdominal CT study and confirmed by exploratory laparotomy. Finally, the herniated ileal loops were reduced, and the redundant peritoneum was resected. In the present case, CT demonstrates the precise anatomic diagnosis and shows acute complications that should be recommended preoperatively. Urgent surgical intervention is necessary to prevent strangulation, which is responsible for high mortality. Early diagnosis and treatment had a good outcome.