Interior of cecum and appendix
This specimen shows the appendix and the internal features of the caecum.
The caecum is a large, dilated, blind sac, located at the commencement of the large intestine. Above, it continues with the ascending colon, medially with the ileum and posteromedially with the appendix. Its interior presents two orifices, namely the ileocaecal orifice and the appendicular orifice. The ileocaecal orifice is guarded by the Ileocaecal valve and the appendicular orifice is guarded by a mucosal fold known as valve of Gerlach. The ileocaecal valve is formed by two ileocaecal valve lips, joined in the ends by the frenula.
The ileum is the terminal part of the small intestine. Histologically, its mucosa shows numerous lymphoid follicles, known as Payer‚Äôs patches. The ileum opens into the caecum through the ileocaecal valve situated at the ileocaecal junction.
Its interior presents a valve, known as, the ileocacecal valve. This is guarded by two lips. The two lips meet at the ends in the form of mucous folds, called, the caecal frenula
The Ileocaecal valve is located at the posteromedial aspect of the caecocolic junction where the ileum opens into the caecum. The valve presents two ileocaecal valve lips (upper and lower). The ileocaecal valve regulates the unidirectional flow of contents from the ileum to the caecum and prevents the regurgitation of contents back to ileum.
Ileocaecal valve lips:
The ileocaecal valve lips (upper and lower) guard the ileocaecal valve. The upper lip is horizontal whereas the lower lip is concave above. These lips meet at the ends to form the mucosal folds known as frenula.
The ends of the ileocaecal valve lips meet to form the mucosal folds known as the frenula.
The appendix is a worm-like diverticulum from the caecum. It is the narrowest part of the gastrointestinal tract. It presents a tip, a base and a body. The tip is movable and points at various directions. The most common position of the tip is the retrocaecal position. The base is attached to the posteromedial wall of the caecum 2cms below the ileocaecal junction. Its mucosa is made up of numerous lymphoid aggregations. Inflammation of the appendix is known as appendicitis. Maximum tenderness during appendicitis can be elicited at the McBurney‚Äôs point on the anterior abdominal wall.