The ureter is a fibro muscular tube, which is 41 to 46 cm long, through which the urine passes from the kidneys to the bladder. Present in each of the two kidneys, the duct mucosal muscle can ideally be divided into an abdominal portion and a pelvic portion (since it originates in the abdomen and ends in the urinary bladder). As urine is produced by each of the kidneys, it eventually passes into the ureter, which by contracting rhythmically, it forces the urine along and empties it in spurts into the bladder. After it is temporarily stored in the bladder, the urine will pass out of the body by way of the urethra. Occasionally a small calculus or stone may form in the kidneys and will eventually pass into a ureter obstructing it, this is known as a kidney stone.
What are the ureters?
The ureters are the ducts that allow the passage of urine from the kidneys to the bladder. Each tube is composed of a muscular, fibrous, and a mucous coat and divides into an abdominal part and pelvic part. The abdominal part lies behind the peritoneum of the medial side of the major psoas and enters the pelvic cavity via a crossing, which is either the commencement of the external iliac artery or the termination of the common iliac artery. The ureter in males (in the pelvic part) runs along the lateral wall of the pelvic cavity and reaches the later angle of the bladder just under the upper tip of the seminal vesicle. In females the pelvic part of the ureters creates the posterior boundary of the ovarian fossa and runs medially and ventrally along the upper part of the vagina. Urine is pumped through the ureters by peristaltic waves, which occur on average of three times within a minute.
The two ureters are arranged at the sides of the spinal column, vertically. Their diameter, which measures to about one centimeter, while the length is approximately 25 to 30 cm. Internally they are covered by a mucosa wall which comes into contact with the urine, in turn covered by a tunica muscularis which by contracting causes the expulsion of urine in the bladder. Each ureter has in its lower end, in the area of the rear outlet a wall of the bladder, which acts like a valve that allows urine to flow into the bladder but prevents the reverse path, thus preventing the flow of urine back into the kidneys. Despite the way the human organism is designed to only have one ureter for each kidney, ureteral duplicity – namely the presence of two ureters for one kidney – is a congenital malformation that affects up to 0.8% of the population, and that most of the time does not generate any serious health problems, as well as not affecting the functional level.
Among the diseases that affect the ureter, there are those that affect the ureteral wall (including inflammation and malformations), in addition to this is calculosis and neoplasms. Diseases of neighboring organs, such as cancer or sclerosis, may affect the ureter and cause an effect on the state of wellbeing of the patient (i.e. squeezing pain).
What function do the ureters serve?
The function of the ureters is to carry the urine produced by the kidneys from the renal pelvis to the urinary bladder.
