RESUMEN
Dynamic colored meshes (DCM) are widely used in various applications. However, this kind of meshes may undergo different processes, such as compression or transmission, which can distort them and degrade their quality. To facilitate the development of objective metrics for DCMs and study the influence of typical distortions on their perception, we create the Tencent - Dynamic colored Mesh Database (TDMD) containing eight reference DCM objects with six typical distortions. Using processed video sequences (PVS) derived from the DCM, we conduct a large-scale subjective experiment that resulted in 303 distorted DCM samples with mean opinion scores, making the TDMD the largest available DCM database to our knowledge. This database enables us to study the impact of different types of distortion on human perception and offers recommendations for DCM compression and related tasks. Additionally, we have evaluated three types of state-of-the-art objective metrics on the TDMD, including image-based, point-based, and video-based metrics, on the TDMD. Our experimental results highlight the strengths and weaknesses of each metric, and we provide suggestions about the selection of metrics in practical DCM applications. The TDMD is publicly available at the following location: https://multimedia.tencent.com/resources/tdmd.
RESUMEN
Chronic idiopathic ulcers of the colon pose diagnostic challenges due to their elusive etiology and potential resemblance to other intestinal pathologies, such as cecal carcinoma. This case report outlines the clinical course of a 68-year-old female patient who presented to the emergency department (ED) with persistent right lower quadrant pain. Despite multiple hospital visits yielding varied diagnoses, a definitive diagnosis was only made following a laparoscopic partial colectomy, which revealed chronic idiopathic ulcers with transmural scarring and adhesions to adjacent small intestine loops. Histological examination demonstrated a substantial ulcer bed populated by inflammatory cells, including large stellate and spindled stromal cells within the granulation tissue, alongside lymphoid hyperplasia and scar tissue extending into the muscularis propria. The initial presentation of this case could easily be mistaken for appendicitis, diverticulitis, carcinoma, or irritable bowel syndrome, highlighting the significance of considering chronic idiopathic ulcers in the differential diagnosis of patients presenting with cecal masses.
RESUMEN
During a routine dissection of the abdominal region in our department of anatomy's dissection laboratory, we found two variations of the vasculature of the gastrointestinal tract within the greater peritoneal and retroperitoneal compartments: an aberrant left colic artery (LCA) and an accessory right colic artery (RCA). The aberrant LCA originates from a common trunk (CT) that arises from the superior mesenteric artery instead of the inferior mesenteric artery. The CT continues for a short distance and terminates by dividing into a middle colic artery and an accessory RCA. The aberrant LCA and accessory RCA had abnormal courses; therefore, they are vulnerable to injury during surgical procedures of the region. Hence, a thorough knowledge of vascular variations is required to avoid potential complications.