Ureter

Ureter , ureter - a paired, retroperitoneal tubular organ that connects the renal pelvis to the bladder . The length of the ureter is 30-35 cm, the diameter is uneven: at the point of departure from the pelvis, at the entrance to the small pelvis and when passing through the wall of the bladder, it does not exceed 3-4 mm, and between these narrowed segments reaches 9 mm.

There are two parts of the ureter : the abdominal and pelvic.

The abdominal part , pars abdominalis, forms a bend at the place of deviation from the pelvis. Turning down and medially, the ureter passes along the anterior surface of the large lumbar muscle down to the borderline of the pelvis . The pelvic part , the pelvina pars, goes under the peritoneum of the small pelvis, turns forward, medially and down. Having reached the bottom of the bladder, the ureter pierces its wall in an oblique direction and opens into the cavity of the bladder with a slit aperture.

The wall of the ureter consists of three layers.

The adventitia , tunica adventitia, consists of fibrous connective tissue and elastic fibers. In the thickness of the fiber pass the nerves and vessels of the ureter. The ureter is surrounded by an underdeveloped fascia, which is a continuation of the renal fascia.

The muscular membrane , tunica muscularis, consists of three layers: the inner longitudinal, the middle circular and the outer longitudinal. The last layer is not continuous, but is represented by separate bundles, which are larger in the lower part of the ureter.

The mucous membrane , tunica mucosa, forms longitudinally extending folds, as a result of which the lumen of the ureter is star-shaped; Closer to the lower regions of the ureter, the folds are smoothed out and the lumen loses the indicated shape. In the thickness of the mucous membrane, mainly in the upper part of the ureter, there is a small number of small glands.

The topographic relationships of the abdominal region of the right and left ureters are not the same. The right ureter in the initial part is located behind the descending part of the duodenum. The lower part of the abdominal part intersects the root of the mesentery of the ileum. At the level of the border line, it passes in front of the common iliac vessels. The left ureter in the initial section passes behind the duodenal-lean curve, and in the lower part of its ventral part passes the root of the mesentery of the sigmoid colon. When you move to a small pelvis, the ureter crosses the outer iliac vessels.

The right and left ureters cross the ovarian (ovarian) vessels in the middle or upper third of their extent.

The topographical relationships of the intragastric parts on the right and left are the same, but they are different for men and women.

In men immediately before entering the bladder, the ureter crosses the vas deferens, which here passes medially from it; The place of entry into the bladder is located somewhat below the bottom of the rectum-vesicular cavity and corresponds to the tip of the seminal vesicle.

In women, the ureter, descending the wall of the small pelvis, crosses, located superficially, the beginning of the uterine artery; Further, going medially, down and forward, passes in the ovary cellulose and here, at the level of the cervix, crosses the uterine artery, located below it. Still further anteriorly the ureter crosses the anterolateral wall of the vagina and enters the bladder.

Innervation: Sympathetic nerves approach different parts of the ureter: to the upper part - from the plexus renalis, to the lower abdominal part from the plexus uretericus, to the pelvic part - from the plexus hypogastricus inferior. Parasympathetic nerves to the upper part of the ureter come from n. Vagus, and to the bottom - from nn. Splanchnici pelvini.

Blood supply: rr. Ureterici (from a rectalis inferior and a. Vesicalis inferior). Venous blood flows into v. Testicularis (v. Ovaris) and v. Iliaca interna. The lymph flows into the nodi lymphatici lumbales and iliaci interni.

You will be interested to read this:

• Urinary organs.
• The kidneys .
• Bladder .
• Urethra.