**2. The appendix vermiformis**

The appendix vermiform is an anatomical structure located at the end of cecum, commonly in posteromedial projection, located about 1.7 cm below the ileocecal valve, at the end of the taenias of the colon converging on the cecum. Its size is about 91.2 mm long in men and 80.3 mm in women, respectively. The appendix is a true diverticulum, as its layer is made up of mucosa, submucosa, longitudinal and circular muscle, and serosa. Anatomically, the position of the appendix just located anterior to the iliopsoas muscle and the lumbar plexus, and posterior to the layers of abdominal wall muscles. The main blood supply to the appendix comes from the appendicular artery, one branch of ileocolic artery, which extends along the mesoappendix to the distal tip of the appendix. Mesoappendix is a mesenterium consists of connective tissue anchoring the appendix into the mesentery of the intestines which size varies to the size of the appendix itself. Somehow, angle and projection of the appendix may differ from one to another: retrocecal, subcecal, preileal, postileal, and pelvic (**Figure 1**) [6, 7].

Nutrition of the vermiform appendix was obtained by special vessels vasculating the appendix running along the mesoappendix. Main nutrition and oxygenation living the appendix are supplied by the appendicular artery, derived and branched from the ileocolic artery alongside the ileum, cecum, and ascending colon. The
