The Anatomy of the Urinary System consist of: Kidneys, ureters, bladder and urethra. Urine is created in the renal tubules, and it is stored in the kidney’s renal pelvis. Urine flows from the kidneys, passing through the ureters to the bladder. Urine builds up in the bladder until it is ejected from the body through the urethra.
What is Ureter?
Ureter is the canal through which urine is transported from the kidney to the bladder. The ureters are two deep tubes that connect the kidneys to the bladder back. Each one has a length of 30 centimeters (approximate), which advance from the bottom of each kidney, following through the lower abdomen and the pelvis first area.
Where is ureter located?
Ureter is located in the abdominopelvic visceral area, sharing place with the pancreas, the liver and the spine. This tube has very interesting characteristics, because it has the capacity to control the urinary flow, namely sphincter.
Picture 1: Location of Ureter in the human body
Structure
The Ureter inner frame is mucous, in order to guarantee an operative transportation of the urine and those mixtures that shape in the kidneys.
Picture 2: Structure of ureters
The wall of the ureters consists of three layers. The remotest is the adventitia, composed by connective tissue with plentiful blood jugs, lymphatics and nerves. This covering, in turn, protects the transitional muscle coat, helping with plane muscle fibers, and the deepest layer or mucosa (created by inside layer epithelium). The ureters act similarly to the esophagus (in Digestive System). Both are passages, but they are not passive.
Function of Ureter
The elementary structure of the ureter is elastic muscles entangled in fiber layers, that allow to control the sphincter. The muscular layers cover the whole path between the kidney to the bladder. The kidneys produce urine by filtering excess water from our blood. The blood transports the debris to the kidneys. From there, the urine passes through two tiny tubes, ureters, into the bladder. The ureters measure between 20 and 26 cm. The muscles in the ureters walls contract and relax, in order to force the urine to go away from the kidneys. Small quantities of urine flow from the ureters to the bladder every single 10-15 seconds.
Through a sequences of ureters walls contractions and relaxations, the tubular structure advances. Unified with the urinary bladder (the next section of the urinary tract) are located the ureteral orifices, which allow the urine pass through. The ureters regulate the course of the urine, in a single direction. However, they do not work like other body sphincters, preventing reflux. Thus, if there is any abnormality in ureter tubes (and orifices), it is probable the urine return to the kidneys, leading to physiologic complications.
Clinical significance
Clinical problems with the ureters can get up from an obstruction, or from an injury. In addition, if the urine turn into stuck, a urinary tract infection may progress. Medical professionals diagnose ureter problems using a set of scientific useful tests. The several examinations include: urinalysis, x-rays, also a test with a special catheter, using a small camera named cystoscopy. Clinical treatment differs depending on the source of problem. It may include medicines and, in serious cases, surgery.
Hydronephrosis
Hydronephrosis is defined as a dilatation of renal gathering system due to difficulty in the urine elimination, caused by complications, which may be mechanical or functional. This clinical problem may be accompanied by progressive degeneration of the renal parenchyma. It may be due to a mechanical origin that leads obstruction at any level of the urinary region, making it difficult to eject urine. A functional origin is less frequently, due to poor evacuation of the urinary bladder or by vesicoureteral reflux.
Urinary tract Obstruction
An obstruction of the urinary tract impedes the flow of urine through the normal route. The obstruction can be total or partial. The obstruction may lead to kidneys damage, kidney stones, and infection. Symptoms include, but are not limited to, pain in the side, reduced or enlarged urine flow, and need to urinate at night. Diagnostic examinations include: Introduction of a urethral catheter, insertion of an observation tube into the urethra (ureteroscopy), and diagnostic imaging tests. Treatment is based on clinical actions to open the blocked course, and then to treat the origin of the obstruction. A blockage at any point in the urinary tract can lead to an increase of pressure in the urinary tract, reducing the flow of urine. This serious problem can happen brusquely or gradually advance over several days, weeks, or months, and finally can lead to an occlusion of the urinary tract. Sometimes only one kidney is affected, but the obstruction can affect both kidneys.
Each year, about 2 in 1,000 people in the developed countries are hospitalized for urinary tract obstruction. In children, the obstruction is mainly due to congenital abnormalities that damage the urinary tract. Men, particularly those over 60 years old, are more likely to be affected because aging makes the prostate have a tendency to increase in size, blocking the urine flow.
Mechanical alterations can originate in the kidney, ureter or urethra:
- Kidney: The most common origins are calculus (lithiasis) concretion, infections, benign or malignant tumors, and congenital abnormalities, such as pyeloureteral stenosis.
- Ureter: Congenital malformations such as narrowing, kinking or ureteroceles may be in the ureter. In adult people, the most common origins are lithiasis, and compression due to an abdominal tumor.
- Urethra: There may also be congenital alterations that result in obstruction, such as urethral valves, including external compression due to a prostate enlargement.
Imperfections in the ureter canal are very ambiguous, all of them mostly prejudiced by a change in the patient’s anatomy, or a complication in the kidneys area. Retroperitoneal Fibrosis generates tumors that, by collecting shape and dimension, can detour the ureter until it is constrained against the wall of tissues blocking the canal. Large kidney stones may lead to break the ureter muscle tissues.
Repairing ureter terminal surgery
Ureterovesical reimplantation is a surgical intervention that aims to reconnect the higher, healthy section of the ureter (to the bladder), when there is an obstruction to the proper passage of urine in the lower ureter (due to fibrosis, tumor, lithiasis, fistula, etc.), and to prevent the progressive kidney function loss. This repairing surgery requires: general anesthesia, approaching the ureter by a pararectal incision, ilioinguinal or infraumbilical. Once the stenosis area is located, and the non-viability of the termino terminal anastomosis of the ureteral segments is verified, the ureter is reimplanted distal to the bladder.
Prevention
There is no 100% effective method to prevent infections in the urinary system, however, changing some of our daily habits, we can avoid them:
- We must always drink at least 1.5 liters to 2 liters per day of water (plus another healthy liquid) to eliminate the bacteria. Cranberry juices work very well, as well as vitamin C, as they increase the acidity in urine, preventing bacteria from growing.
- We should urinate frequently: Whenever we feel like urinating, we should not delay it, because maintaining the urine cause the bacteria will reproduce more easily.
- It is also recommended to wear loose cotton underwear, because it allows the entry of air, keeping the area dry.
- In sexual relations, it is advisable to urinate after finish, in order to eliminate bacteria that have been introduced into the urethra during coition.
- In the case of women, latex condoms stimulate the growth of bacteria, so it is better to change the contraceptive method (when there is possibility to do).
