Pulmonary sclerosing hemangioma: report of two cases.

Pulmonary sclerosing hemangioma (PSH) is a rare benign tumor of the lungs. These tumors are composed of cuboidal surface cells and polygonal stromal cells and show four histological manifestations: hemorrhagic, papillary, solid, and sclerotic. PSH predominantly affects asymptomatic middle-aged women. The tumor often occurs at the intralobar site, and less commonly in the bronchus and mediastinum. PSH is easy to be misdiagnosed preoperatively. In this study, we present in detail the treatment procedures followed for two atypical cases of PSH. Case 1 was a 62-year-old woman bearing a tumor for 15 years. The tumor lesion was found to be located in the oblique fissure of the left lung. PSH was confirmed by surgical resection and postoperative pathological diagnosis. There was no sign of recurrence and metastasis 1.5 years after surgery. Case 2 was a 54-year-old woman diagnosed with bilateral multiple nodules by physical examination. This patient was diagnosed with definite PSH through computed tomography-guided percutaneous lung biopsy. Surgical resection was not performed. The patient also showed no sign of enlarged tumor and metastasis after 2 years of follow-up. Although PSH can be cured by surgical resection, the findings in our cases indicate that surgical resection need not be considered the preferred course of treatment. If PSH is diagnosed before surgery, the patients may survive while bearing the tumor.

Biomechanical behaviour of temporomandibular joints during opening and closing of the mouth: A 3D finite element analysis.

Temporomandibular joints (TMJs) constitute a pair of joints that connect the jawbone to the skull. TMJs are bilateral joints which work as one unit in conducting daily functions such as speaking, mastication, and other activities associated with the movement of the jaw. Issues associated with the TMJs may arise due to various factors-one such factor being the internal load on the TMJ. These issues may contribute to temporomandibular disorders (TMD). This study aims to evaluate the mandibular trajectories and the associated stress changes during the process of opening the mouth on the TMJs of an asymptomatic subject. The mouth opening motion was recorded by a motion capturing system using models of the mandible and maxilla constructed based on the computed tomography (CT). Two discs constructed based on magnetic resonance imaging (MRI). Finite element analysis was performed on the relative motion of the mandible to the maxilla and validated. The process modelled by these displacements provided less than 10% error in terms of deformation. The simulation results indicate that the lateral intermediate zone-the head and neck of the mandible-and the articular eminence sustained the most significant stresses during the mouth opening motion. The results also suggested that the stresses increase as the range of opening increases with the greatest von Mises stress, tensile, and compressive stress found at the position of maximal opening.