Pathology

I. Gross Anatomy and Histology

Objectives:

After going through this section you will be able to:

• list and identify the various parts of the fallopian tube
• describe the gross anatomy and histology of the fallopian tube

1. Anatomy

The fallopian tubes (uterine tubes, salpinx uteria, oviducts) are bilateral ducts, about 10 cm long, that lie in the upper border of the broad ligament and connect the uterine cavity to the peritoneal cavity near the ovaries. Each tube is divided into 4 parts:

Infundibulum, the funnel-shaped, expanded lateral end of the tube, which projects beyond the broad ligament and overlies the ovary. The free edge has many finger-like processes, the fimbriae, suspended over the ovary. It contains the abdominal ostium of the tube.

Ampulla, the intermediate segment, is next to the infundibulum. It is wide and tortuous.

Isthmus, the narrow portion lies just lateral to the uterus.

Intramural (interstitial), the uterine portion of the tube. This pierces the uterine wall, and through the uterine ostium, opens into the endometrial cavity.

2. Histology

The wall of the fallopian tube consists of:

Mucosa, the inner layer. In the ampulla, this is relatively thick and forms numerous elaborately branched finger-like processes, the plicae, which gives a cross-section a maze-like appearance. In the isthmus, the plicae are shorter and less branched, and in the intramural segment, they are reduced to low ridges. The mucosa is lined by simple columnar epithelium. The epithelial cells are tallest in the infundibulum and ampulla and shorter in the isthmus. Two types of epithelial cells, ciliated and non-ciliated, are found the latter being secretory cells. The lamina propria contains fibroblasts, reticular fibers and a few lymphocytes and macrophages. There is no muscularis mucosae.

Muscularis, the middle coat of smooth muscle. The mucosa rests directly on this. It has three layers, an innermost circular bundle, which merges with a middle layer of mixed circular and longitudinal smooth muscle fibers and an outer longitudinal bundle.

Serosa, the peritoneal covering, is the outermost layer.