The intramural ureter is the most distal part of the organ, located in the thickness of the surface of the bladder and opening into its cavity with the help of the mouth. The length of this section is about 1.5-2 cm. The intramural section is one of the four zones of physiological narrowing in the organ (except for the intramural part, similar narrowings are observed in the juxtavesical region, in the areas of transition of the pelvis to the ureter and interlacing with the iliac vessels).
Importance of the department
In clinical medicine, the importance of the intramural ureter is due, firstly, to the fact that it is a natural antireflux mechanism that does not allow urine to flow back during urination in he althy people with an increase in intravesical pressure. Secondly, in this department most oftenthere is the presence of small stones, which, due to the common innervation with the bladder, can be clinically manifested not only in the form of renal colic, but also in the form of dysuria. Intramural ureter - where is it? So what's this? Let's take a closer look at all these issues, talk about the features of the treatment of urolithiasis.
What is this?
Let's give a brief description. The ureter is a urinary paired organ that serves to remove urine from the kidneys into the cavity of the bladder. First, the upper sections are filled with urine, and thanks to the contractions of the muscle structures in its wall, the urine moves further into the cavity of the bladder, even if the person is in a horizontal position at that time.
The ureter is divided into three sections: distal, abdominal and pelvic. The abdominal is localized in the retroperitoneal wall behind the abdomen and is adjacent to the lumbar muscles. It begins behind the duodenum, and closer to the pelvic zone passes behind the mesentery of the sigmoid colon. The pelvic region in women is located behind the ovaries, goes around the uterus on the sides, runs along its wide ligament, in the lumen between the bladder and the vaginal wall. The difference between the abdominal ureter in men is that the tubes of this organ are outside the seminal ducts, and enter the bladder above the upper side of the seminal bladder.
The distal zone of the organ is the most remote from the kidneys, and the second name of this area is the “intramural section”. It is localized directly in the wall thickness of the urinarythe bubble and its length is only 1.5–2 cm.
Building
The ureter in the anatomy of the human body is a very important structure that connects the kidneys to the bladder. This is a paired tubular hollow organ, which is a muscular connective tissue. Its length is approximately from 25 to 35 cm. The diameter, which has no anatomical pathologies, ranges on average from 2 to 8 mm.
Features of the organization of the muscular structures of the ureter are such that it consists of:
- outer muscle tissue;
- intrinsic muscle tissue;
- vessels that feed the body;
- epithelial layer covered with mucous membranes.
Outer layer
The outer layer is covered with an adventitial membrane and fascia, and in the intraparietal areas, the mucous membrane is anatomically divided into:
- transitional epithelial layer, which is located in the organ in several rows;
- epithelial plates containing elastic fibers of muscle tissue collagen.
Thus, the entire internal part of this hollow organ is made up of many longitudinal folds, which provide an inseparable stretching of the parts of the ureter, which prevents the backflow of urine into the kidney. What are the features of the organization of the muscular structures of the ureter?
The structure of muscle layers
Directly muscle tissue, which is the basis for the structure and normal functioning of the ureters. itpeculiar bundles of muscle cells of different thickness, which can be arranged as follows:
- obliquely;
- lengthwise;
- crosswise.
The upper layers of muscle tissue consists of two interpenetrating sublayers: circular and longitudinal. The lower, inner part of the muscle layer contains three sublayers - two longitudinally located and one circular layer of cells between them. Between the bundles of myocyte cells in the muscles there are nexus cells that have a connecting function, they also pass through the epithelial plates and through the adventitia.
The ureter in men is 2-3 cm longer than in women, and the right ureter in all people is 1-1.5 cm shorter than the left, since the activity and development of the left kidney is always higher.
The lumen of the organ cavity also differs, in the context it resembles an accordion. The most significant narrowing of the internal lumens are located:
- behind the pelvis;
- at the beginning of the pelvic and ending of the abdominal part;
- when entering the bladder.
It is these narrowed areas of the ureter, including the intramural section, that are most often exposed to various pathologies, infections and congestion. The narrowest points vary in diameter from 2 to 4 mm, but they have the ability to expand up to 8 mm.
Abdominal and pelvic areas are different in diameter of the internal cavity:
- behind the abdominal wall - from 6 to 8 mm, and the expansion of this part can reach up to 14.5 mm;
- organs passing through the pelvic area have an internal lumenapprox. 4 mm, expandable to 8 mm.
Blood supply to the area
All parts of the ureters are filled and nourished by arterial blood. The vessels are located in the adventitial part of the membrane, and capillaries pass from them into the organ.
In the upper part, the arterial branches come from the renal artery. The middle section is connected by the common internal iliac artery and the abdominal aorta. The lower section is powered by branches of the iliac arteries, such as the cystic, uterine and rectal. In the abdominal region, the vascular plexus is located in front of the ureter, and in the pelvic region - behind it.
As for venous blood flow, it is provided by the veins of the same name, located not far from the arteries. Blood from the lower part of the organ goes into the iliac internal veins, and from the upper part into the testicular veins. Lymph flow is provided by the lumbar and internal iliac lymph nodes.
Features of the functioning of the organ
The functions of the ureter are controlled by the autonomic nervous system. The branches of the vagus nerve approach the upper section of this organ, and the lower section is innervated by the pelvic nerve plexuses. The main function of the ureters is to push fluid from the renal pelvis to the bladder, which is provided by contractions of muscle tissue cells. The rhythm of such contractions is set by the cells of the ureteropelvic segment, but it can vary depending on:
- of the kidneys, that is, the speed with which it is filteredurine;
- body position, i.e. standing, sitting or lying down;
- urethral and bladder conditions;
- work of the autonomic nervous system.
The level of calcium in the body has a direct effect on the functionality of the organ. It is the concentration of calcium in the muscle tissue that determines the force with which the ureter contracts, and the calcium content in the cells ensures equal pressure in the kidneys, where the ureter begins, and along its entire length, and in the bladder.
The norm is the pumping of urine in a volume of 10-14 ml per minute. As for the internal pressure, it can "adjust" to the kidneys, and in the cavity of the bladder - to the ureters. The process is called vesicoureteral reflux, and its appearance causes pain and physiologically unpleasant moments.
Stone in intramural ureter
Ureterolithiasis (stones in this organ) is dangerous with serious and severe complications. Stones that disrupt the passage of urine cause loosening of the mucous membrane of the organ, hypertrophy of the muscle walls, and hemorrhages in the submucosal layer. Over time, such changes lead to atrophy of the nerve and muscle fibers of the ureter, a decrease in its tone, hydroureteronephrosis and ureterectasia.
The most common localizations of stones that have formed in the kidneys and displaced this organ are areas of narrowing. In most cases, this is its mouth - the intramural ureter. Here the stones often stop and the patientmedical assistance is required to remove them.
Treatment of this pathology
The dissolution of intramural calculi of the right or left ureter can be carried out with drugs, but this condition is usually very painful. In this case, prompt assistance is often required (if the stone is large), or an increase in the patient's motor activity so that the calculus quickly passes through the mouth into the bladder.
With planned treatment, stones in the intramural ureter can be expelled with medication. This method is used for grinding formations. Small grains of sand come out by themselves absolutely painlessly. Those that are larger, under the influence of drugs, break up into fragments.
Urolithiasis treatment method
Urate stones in the development of urolithiasis in most cases are eliminated with allopurinols ("Silorik", "Sanfipurol"). Medicines such as Blemaren, Canephron N and Urolesan act quickly. Phosphate stones are broken down by the drug "Marelin", which is made on the basis of vegetable raw materials. Oxalate stones are removed with the help of the drug "Prolit" and means for alkalizing urine. In the treatment of cystine formations, "Thiopronin", "Penicillamine" are prescribed.
To accelerate the release of the stone from the lumen of the ureter, it is recommended to take antispasmodics - "Papaverine", "No-shpa". At the same time, the muscles of these hollow structures relax, and their lumen expands, which contributes toadvancing stones. In difficult cases, surgery or crushing of kidney stones in the intramural ureter is prescribed.
