The ureters are tubes made of smooth muscle that propel urine from the kidneys to the urinary bladder. In the human adult, the ureters are usually long and around in diameter. The ureter is lined by urothelial cells, a type of transitional epithelium, and has an additional smooth muscle layer in third closest to the bladder that assists with peristalsis. The ureters can be affected by a number of diseases; including urinary tract infections and kidney stone. is when a ureter is narrowed, due to for example chronic inflammation. Congenital abnormalities that affect the ureters can include the development of two ureters on the same side, or abnormally placed ureters.
Introduction
Ureter
Ureter | Introduction
The ureters are tubes made of smooth muscle that propel urine from the kidneys to the urinary bladder. Tubes made to propel urine from the kidneys to the urinary bladder. The ureters are tubes made of smooth muscle that propel urine from the kidneys to the urinary bladder They are tubes made of smooth muscle that propel urine from the kidneys to the urinary bladder
what tissue types form the wall of the ureter
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urothelial cells
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The ureter is lined by urothelium, a type of transitional epithelium that is capable of responding to stretches in the ureters. The transitional epithelium may appear as a layer of column-shaped cells when relaxed, and of flatter cells when distended. Below the epithelium sits the lamina propria. The lamina propria is made up of loose connective tissue with many elastic fibers interspersed with blood vessels, veins and lymphatics. The ureter is surrounded by two muscular layers, an inner longitudinal layer of muscle, and an outer circular or spiral layer of muscle. The lower third of the ureter has a third muscular layer.
Ureter | Microanatomy
The ureters are tubes made of smooth muscle that propel urine from the kidneys to the urinary bladder. In the human adult, the ureters are usually long and around in diameter. The ureter is lined by urothelial cells, a type of transitional epithelium, and has an additional smooth muscle layer in third closest to the bladder that assists with peristalsis. The ureters can be affected by a number of diseases; including urinary tract infections and kidney stone. is when a ureter is narrowed, due to for example chronic inflammation. Congenital abnormalities that affect the ureters can include the development of two ureters on the same side, or abnormally placed ureters.
Ureter | Introduction
The ureters are richly supplied by nerves that form a network () of nerves, the ureteric plexus that lies in the adventitia of the ureters. This plexus is formed from a number of nerve roots directly (T9-12, L1, and S2-4), as well as branches from other nerve plexuses and nerves; specifically, the upper third of the ureter receives nerve branches from the renal plexus and aortic plexus, the middle part receives branches from the upper hypogastric plexus and nerve, and the lower ureter receives branches from the lower hypogastric plexus and nerve. The plexus is in the adventitia. The these nerves travel in individual bundles and along small blood vessels to form the ureteric plexus.
Ureter | Nerve supply
Beyond these layers sits an adventitia containing blood vessels, lymphatic vessels, and veins.
Ureter | Microanatomy
The ureters develop from the ureteric buds, which are outpouchings from the mesonephric duct. This is a duct, derived from mesoderm, found in the early embryo. Over time, the buds elongate, moving into surrounding mesodermal tissue, dilate, and divide into left and right ureters. Eventually, successive divisions from these buds form not only the ureters, but also the pelvis, major and minor calyces, and collecting ducts of the kidneys. The mesonephric duct is connected with the cloaca, which over the course of development splits into a urogenital sinus and the anorectal canal. The urinary bladder forms from the urogenital sinus.
Ureter | Development
Ureteritis is a medical condition of the ureter that involves inflammation. One form is known as "ureteritis cystica". Eosinophilic ureteritis has been observed. Ureteritis is often considered part of a urinary tract infection.
Ureteritis | Introduction
IVU-shows Adder head appearance or Cobra head appearance. Cystoscopy-shows translucent cyst which is thin walled surrounding ureteric orifice
Ureterocele | Diagnosis
From here, in males they cross under the vas deferens and in front of the seminal vesicles to enter the bladder near the trigone. In females, the ureters pass behind the ovaries, and then travel in the lower midline section of the broad ligament of the uterus. For a short part, the uterine arteries travel on top for a short (2.5 cm) period. They then pass by the cervix, travelling inwards towards the bladder.
Ureter | Structure
Cancer of the ureters is known as ureteral cancer. It is usually due to cancer of the urothelium, the cells that line the surface of the ureters. Urothelial cancer is more common after the age of 40, and more common in men than women; other risk factors include smoking and exposure to dyes such as aromatic amines and aldehydes. When cancer is present, the most common symptom in an affected person is blood in the urine; it may not cause symptoms, and a physical medical examination may be otherwise normal, except in late disease. Ureteral cancer is most often due to cancer of the cells lining the ureter, called transitional cell carcinoma, although it can more rarely occur as a squamous cell carcinoma if the type of cells lining the urethra have changed due to chronic inflammation, such as due to stones or schistosomiasis.
Ureter | Cancer
Sensation supplied is sparse close to the kidneys and increases closer to the bladder. Sensation to the ureters is provided by nerves that come from T11 - L2 segments of the spinal cord. When pain is caused, for example by spasm of the ureters or by a stone, the pain may be referred to the dermatomes of T11 - L2, namely the back and sides of the abdomen, the scrotum (males) or labia majora (females) and upper part of the front of the thigh.
Ureter | Nerve supply
The ureters are tubular structures, approximately in adults, that pass from the pelvis of each kidney into the bladder. From the renal pelvis, they descend on top of the psoas major muscle to reach the brim of the pelvis. Here, they cross in front of the common iliac arteries. They then pass down along the sides of the pelvis, and finally curve forwards and enter the bladder from its left and right sides at the back of the bladder. The ureters are between 1.5 - 6 mm in diameter, and surrounded by a layer of smooth muscle for 1 - 2 cm near their ends just before they enter the bladder.
Ureter | Structure
The difference between the two could lead to fluid entering or exiting the ureter due to the osmotic pressure. Histologie 1er cycle des études médicales, Lüllman-Rauch, 2008
Facet cells | Introduction
A ureteral neoplasm is a type of tumor that can be primary, or associated with a metastasis from another site. Treatment may involve removal of the kidney and ureter, or just the ureter. Classification of cancers often is oriented around the embryological origin of the tissue. In some contexts, the primary division is at the border of kidney and ureter, and in other contexts, the primary division is between derivatives of the metanephric blastema and those of the ureteric bud. Because of this, neoplasia of the ureters are sometimes grouped with tumors of the renal pelvis.
Ureteral neoplasm | Introduction
In the human female, the urethra is about 4 cm long, and exits the body between the clitoris and the vagina, extending from the internal to the external urethral orifice. The meatus is located below the clitoris. It is placed behind the symphysis pubis, embedded in the anterior wall of the vagina, and its direction is obliquely downward and forward; it is slightly curved with the concavity directed forward. The proximal two-thirds of the urethra is lined by transitional epithelial cells, while the distal third is lined by stratified squamous epithelial cells. Between the superior and inferior fascia of the urogenital diaphragm, the female urethra is surrounded by the urethral sphincter.
Urethra | Female
As it passes down the muscle, it travels over the genitofemoral nerve and. The inferior vena cava and the abdominal aorta sit to the midline of the right and left ureters respectively. In the lower part of the abdomen, the right ureter sits behind the lower mesentery and the terminal ileum, and the left ureter sits behind the jejunum and the sigmoid colon. As the ureters enter the pelvis, they are surrounded by connective tissue, and travel backwards and outwards, passing in front of the internal iliac arteries and internal iliac veins. They then travel inwards and forwards, crossing the umbilical, inferior vesical and middle rectal arteries.
Ureter | Structure
The word "ureter" comes from the Ancient Greek stem "uro" relating to urination, and the first use of the word is seen during the era of Hippocrates to refer to the urethra. The anatomical structure of the ureter was noted by 40 AD. However, the terms "ureter" and "urethra" were variably used to refer to each other thereafter for more than a millennium. It was only in the 1550s that anatomists such as Bartolomeo Eustacchio and Jacques Dubois began to use the terms to specifically and consistently refer to what is in modern English called the ureter and the urethra.
Ureter | History
The ureters enter the bladder from its back surface, traveling before opening into the bladder at an angle on its outer back surface at the slit-like "ureteric orifices". This location is also called the vesicoureteric junction. In the contracted bladder they are about apart and about the same distance from the internal urethral orifice; in the distended bladder these measurements may be increased to about . A number of structures pass by, above, and around the ureters on their path down from the kidneys to the bladder. In its upper part, the ureter travels on the psoas major muscle, and sits just behind the peritoneum.
Ureter | Structure
An urothelial papilloma (or Transitional cell papilloma) is a papilloma developed from the urothelium.
Urothelial papilloma | Introduction
The urethra is a fibrous and muscular tube which connects the urinary bladder to the external urethral meatus. Its length differs between the sexes, because it passes through the penis in males.
Urethra | Structure
The ureters are muscular ducts that propel urine from the kidneys to the urinary bladder. In the human adult, the ureters are usually 25–30 cm (10–12 in) long. In humans, the ureters arise from the renal pelvis on the medial aspect of each kidney before descending towards the bladder on the front of the psoas major muscle. The ureters cross the pelvic brim near the bifurcation of the iliac arteries (which they run over). This "pelviureteric junction" is a common site for the impaction of kidney stones (the other being the uteterovesical valve). The ureters run posteriorly on the lateral walls of the pelvis.
Excretory system | Ureter
Ureteral cancer is cancer of the ureters, muscular tubes that propel urine from the kidneys to the urinary bladder. It is also known as ureter cancer, renal pelvic cancer, and rarely ureteric cancer or uretal cancer. Cancer in this location is rare. Ureteral cancer is usually transitional cell carcinoma. Transitional cell carcinoma is "a common cause of ureter cancer and other urinary (renal pelvic) tract cancers."
Ureteral cancer | Introduction
The cells lining the urethra (the epithelium) start off as transitional cells as it exits the bladder, which are variable layers of flat to cuboidal cells that change shape depending on whether they are compressed by the contents of the urethra. Further along the urethra there are pseudostratified columnar and stratified columnar epithelia. The lining becomes multiple layers of flat cells near the end of the urethra, which is the same as the external skin around it. There are small mucus-secreting urethral glands, as well as bulbo-urethral glands of Cowper, that secret mucous acting to lubricate the urethra. The urethra consists of three coats: muscular, erectile, and mucous, the muscular layer being a continuation of that of the bladder.
Urethra | Microanatomy
The anatomy of "Tomigerus clausus" was examined by Harold Heath in 1914. The mantle has more highly thickened margins and more glandular epithelium than in the genus"Anostoma", extending throughout the body whorl of the shell to the region adjacent to the aperture. It thus terminates at the point where the ureter bends abruptly upon itself. The external openings of the ureter and intestine occupy the usual positions on the right side, and from this point they pursue a course parallel to the external surface of the body, in close contact with the mantle cavity. The ureter bends sharply upon itself at the termination of the mantle cavity, and, dorsally placed with reference to this chamber, proceeds anteriorly to unite with the forward extremity of the kidney.
Tomigerus clausus | Anatomy
Pseudostratified columnar – proximally, Stratified squamous – distally
Spongy urethra | Epithelium
In males the neck of the urinary bladder is next to the prostate gland. The bladder has three openings. The two ureters enter the bladder at ureteric orifices, and the urethra enters at the trigone of the bladder. These ureteric openings have mucosal flaps in front of them that act as valves in preventing the backflow of urine into the ureters, known as vesicoureteral reflux. Between the two ureteric openings is a raised area of tissue called the interureteric crest. This makes the upper boundary of the trigone. The trigone is an area of smooth muscle that forms the floor of the bladder above the urethra.
Urinary bladder | Structure
Blockage, or obstruction of the ureter can occur, as a result of narrowing within the ureter, or compression or fibrosis of structures around the ureter. Narrowing can result of ureteric stones, masses associated with cancer, and other lesions such as endometriosis tuberculosis and schistosomiasis. Things outside the ureters such as constipation and retroperitoneal fibrosis can also compress them. Some congenital abnormalities can also result in narrowing or the ureters. Congenital disorders of the ureter and urinary tract affect 10% of infants. These include partial or total duplication of the ureter (a duplex ureter), or the formation of a second irregularly placed () ureter; or where the junction with the bladder is malformed or a ureterocoele develops (usually in that location).
Ureter | Anatomical and surgical abnormalities
Related to the urinary bladder, anteriorly there are the following folds:
Umbilical folds | Introduction
The urethral sponge is a spongy cushion of tissue, found in the lower genital area of females, that sits against both the pubic bone and vaginal wall, and surrounds the urethra.
Urethral sponge | Introduction
Since it has no muscles to regulate urination, urine collects in a bag. There are four common types of ureterostomies:
Ureterostomy | Types
Over time, as the bladder enlarges, it absorbs the surrounding parts of the primitive ureters. Finally, the entry points of the ureters into the bladder move upwards, owing to the upward migration of the kidneys in the developing embryo.
Ureter | Development
The ureteric plexus is a nerve plexus covering and innervating the ureter. The plexus can be graduated into three parts, as the ureter itself can be divided: In the upper part of the ureter, the plexus gets its nerve fibers mainly from the renal plexus, but also from the abdominal aortic plexus. In the intermediate part the plexus receives nervous input from the superior hypogastric plexus and in the lower part from the inferior hypogastric plexus. The plexus contains both sympathetic and parasympathetic fibers, where the sympathetic components come from T11 to L2 levels of the spinal cord. Preganglionic vagal fibers (vagal fibers before passing through a ganglion) run through the celiac plexus and reach the ureteric plexus.
Ureteric plexus | Introduction
through diagnostic imaging performed for unrelated reasons.
Ureterocele | Introduction
The membranous urethra or intermediate part of male urethra is the shortest, least dilatable, and, with the exception of the urinary meatus, the narrowest part of the urethra. It extends downward and forward, with a slight anterior concavity, between the apex of the prostate and the bulb of the urethra, perforating the urogenital diaphragm about 2.5 cm below and behind the pubic symphysis. The hinder part of the urethral bulb lies in apposition with the inferior fascia of the urogenital diaphragm, but its upper portion diverges somewhat from this fascia: the anterior wall of the membranous urethra is thus prolonged for a short distance in front of the urogenital diaphragm; it measures about 2 cm in length, while the posterior wall which is between the two fasciæ of the diaphragm is only 1.25 cm long.
Membranous urethra | Introduction
More invasive forms of imaging include ureteroscopy, which is the insertion of a flexible endoscope into the urinary tract to view the ureters. Ureteroscopy is most commonly used for medium to large-sized stones when less invasive methods of removal are not able to be used.
Ureter | Imaging
Injuries to the ureter can occur after penetrating abdominal injuries, and injuries at high speeds followed by an abrupt stop (such as a high speed car accident). The ureter can be injured during surgery to nearby structures. It is injured in 2 per 10,000 cases of vaginal hysterectomies and 13 per 10,000 cases of abdominal hysterectomies, usually near the suspensory ligament of the ovary or near the cardinal ligament, where the ureter runs close to the blood vessels of the uterus.
Ureter | Injury
Under microscopy, the urinary system is covered in a unique lining called urothelium, a type of transitional epithelium. Unlike the epithelial lining of most organs, transitional epithelium can flatten and distend. Urothelium covers most of the urinary system, including the renal pelvis, ureters, and bladder.
Urinary system | Microanatomy
The arteries which supply the ureter vary along its course. The upper third of the ureter, closest to the kidney, is supplied by the renal arteries. The middle part of the ureter is supplied by the common iliac arteries, direct branches from the abdominal aorta, and gonadal arteries; the gonadal arteries being the testicular artery in men and the ovarian artery in women. The lower third of the ureter, closest to the bladder, is supplied by branches from the internal iliac arteries, mainly the superior and inferior vesical arteries. The arterial supply can be variable, with arteries that contribute include the middle rectal artery, branches directly from the aorta, and, in women, the uterine and vaginal arteries.
Ureter | Blood and lymphatic supply
The arteries that supply the ureters end in a network of vessels within the adventitia of the ureters. There are many connections () between the arteries of the ureter, particularly in the adventitia, which means damage to a single vessel does not compromise the blood supply of the ureter. Venous drainage mostly parallels that of the arterial supply; that is, it begins as a network of smaller veins in the adventitia; with the renal veins draining the upper ureters, and the vesicular and gonadal veins draining the lower ureters. Lymphatic drainage depends on the position of lymphatic vessels in the ureter.
Ureter | Blood and lymphatic supply
The wall of the urinary bladder is normally 3–5 mm thick. When well distended, the wall is normally less than 3 mm.
Urinary bladder | Structure
In this case, usually one ureter drains correctly to the bladder, with the duplicated ureter presenting as ectopic.
Ectopic ureter | Introduction
There are two basic types of urostomies. The first features the creation of a passage called an "ileal conduit." In this procedure, the ureters are detached from the bladder and joined to a short length of the small intestine (ileum). The other type of urostomy is cutaneous ureterostomy. With this technique, the surgeon detaches the ureters from the bladder and brings one or both to the surface of the abdomen. The hole created in the abdomen is called a stoma, a reddish, moist abdominal protrusion. The ileal conduit is not painful; it has no sensation. The ureterostomy stoma retains sensation.
Ureterostomy | Types
Ureteral development begins in the human fetus around the 4th week of embryonic development. A ureteric bud, arising from the mesonephric (or Wolffian) duct, gives rise to the ureter, as well as other parts of the collective system. In the case of a duplicated ureter, the ureteric bud either splits or arises twice. In most cases, the kidney is divided into two parts, an upper and lower lobe, with some overlap due to intermingling of collecting tubules. However, in some cases the division is so complete as to give rise to two separate parts, each with its own renal pelvis and ureter.
Duplicated ureter | Pathophysiology
The other, more superficial, portion of the diverticulum, on the other hand, becomes the ureter.
Development of the urinary system | Ureteric bud
Ureteroureterostomies are often performed because of injured or scarred ureters, especially when the ureter in question is damaged in its upper third section. Generally if the patient has distal uretral strictures (narrowing of the ureter), a ureteroureterostomy is not recommended and a ureter reimplantation would be favorable.
Ureteroureterostomy | Reasons for performing procedure
Prognosis can vary markedly depending on the tumour grade, with a worse prognosis associated with an ulcerating lesion.
Ureter | Cancer
Additionally, reflux of urine from the bladder back up the ureters is a condition commonly seen in children. The ureters have been identified for at least two thousand years; with the word ureter stemming from the stem relating to urinating and seen in written records since at least the time of Hippocrates. It is however only since the 1500s that the term "ureter" has been consistently used to refer to the modern structure; and only since the development of medical imaging in the 1900s that techniques such as X-ray, CT and ultrasound have been able to view the ureters. The ureters are also seen from the inside using a flexible camera, called ureteroscopy, which was first described in 1964.
Ureter | Introduction
The internal sphincter is present both in males and females.
Urethra | Introduction
The ureters are a component of the urinary system. Urine, produced by the kidneys, travels along the ureters to the bladder. It does this through regular contractions called peristalsis.
Ureter | Function
The ureteral branches of renal artery are small branches which supply the ureter.
Ureteral branches of renal artery | Introduction
The UR is quite thin, the telson being fairly short in length.
Hyperia macrocephala | Description
[edit on Wikidata] Ureteroureterostomy ( "urétero-uréte-róstomy") is end-to-end connection (anastomosis) of the two portions of a transected ureter; also called ureteroureteral anastomosis and van Hook operation (after Weller van Hook, surgeon).
Ureteroureterostomy | Introduction
The urethral sponge is composed of erectile tissue; during arousal, it becomes swollen with blood, compressing the urethra, helping, along with the pubococcygeus muscle, to prevent urination during sexual activity.
Urethral sponge | Functions
A ureteric stent may be inserted to relieve an obstruction. If the cause cannot be removed, a nephrostomy may be required, which is the insertion of a tube connected to the renal pelvis which directly drains urine into a stoma bag.
Ureter | Anatomical and surgical abnormalities
The researchers stated, "In the mouse, as in human females, tissue organization in the corpora cavernosa of the clitoris is essentially similar to that of the penis except for the absence of a subalbugineal layer interposed between the tunica albuginea and the erectile tissue."
Clitoris | Cats, sheep and mice
Below is a cladogram from their analysis:
Eretmorhipis | Description
Transitional epithelium is a type of stratified epithelium. This tissue consists of multiple layers of epithelial cells which can contract and expand in order to adapt to the degree of distension needed. Transitional epithelium lines the organs of the urinary system and is known here as urothelium. The bladder for example has a need for great distension.
Transitional epithelium | Introduction
They then curve anteriormedially to enter the bladder through the back, at the vesicoureteric junction, running within the wall of the bladder for a few centimeters. The backflow of urine is prevented by valves known as ureterovesical valves. In the female, the ureters pass through the mesometrium on the way to the bladder.
Excretory system | Ureter
Ureterolysis is a surgical procedure aimed at exposing the ureter in order to free it from external pressure or adhesions or to avoid injury to it during pelvic surgery, most often hysterectomy.
Ureterolysis | Introduction
The ureteric bud, also known as the metanephric diverticulum, is a protrusion from the mesonephric duct during the development of the urinary and reproductive organs. It later develops into a conduit for urine drainage from the kidneys, which, in contrast, originate from the metanephric blastema.
Ureteric bud | Introduction
The urethral crest is an anatomical feature present in the urinary system of both males and females. In males, the urethral crest is known as the "crista urethralis masculinae, or the crista phallica, and is a longitudinal fold on the posterior wall of the urethra extending from the uvula of the bladder through the prostatic urethra. It is from 15 to 17 mm. in length, and about 3 mm. in height, and contains muscular and erectile tissue. When distended, it may serve to prevent the passage of the semen backward into the bladder. In females, it is known as the crista urethralis femininae, and is a conspicuous longitudinal fold of mucosa on the posterior wall of the urethra.
Urethral crest | Introduction
Lymph collects in submucosal, intramuscular and advential lymphatic vessels. Those vessels closer to the kidney drain into renal collecting vessels, and from here into the lateral aortic nodes near the gonadal vessels. The middle part of the ureter drains into the right paracaval and interaortocaval nodes on the right, and the left paraaortic nodes on the left. In the lower ureter, lymph may drain into the common iliac lymph nodes, or lower down in the pelvis to the common, external, or internal iliac lymph nodes.
Ureter | Blood and lymphatic supply
The anatomy of the human urinary system differs between males and females at the level of the urinary bladder. In males, the urethra begins at the internal urethral orifice in the trigone of the bladder, continues through the external urethral orifice, and then becomes the prostatic, membranous, bulbar, and penile urethra. Urine exits through the external urethral meatus. The female urethra is much shorter, beginning at the bladder neck and terminating in the vaginal vestibule.
Urinary system | Structure
The urachus is a fibrous remnant of the allantois, a canal that drains the urinary bladder of the fetus that joins and runs within the umbilical cord. The fibrous remnant lies in the space of Retzius, between the transverse fascia anteriorly and the peritoneum posteriorly.
Urachus | Introduction
The larger cranial bulb prevents distal migration, while the longer narrow section maintains the increased diameter of a predilated stricture in the ureter section.
Ureteric balloon catheter | Introduction
When viewed under a microscope the bladder can be seen to have an inner lining (called epithelium), three layers of muscle fibres, and an outer adventitia. The inner wall of the bladder is called urothelium, a type of transitional epithelium formed by three to six layers of cells; the cells may become more cuboidal or flatter depending on whether the bladder is empty or full. Additionally, these are lined with a mucous membrane consisting of a surface glycocalyx that protects the cells beneath it from urine. The epithelium lies on a thin basement membrane, and a lamina propria. The mucosal lining also offers a urothelial barrier against the passing of infections.
Urinary bladder | Microanatomy
Treatment methods include surgery, chemotherapy, radiation therapy and medication.
Ureteral cancer | Treatment
Ureteroscopy is an examination of the upper urinary tract, usually performed with a ureteroscope that is passed through the urethra and the bladder, and then directly into the ureter. The procedure is useful in the diagnosis and treatment of disorders such as kidney stones and urothelial carcinoma of the upper urinary tract. Smaller stones in the bladder or lower ureter can be removed in one piece, while bigger ones are usually broken before removal during ureteroscopy. The examination may be performed with either a flexible, semi-rigid or rigid device while the patient is under anesthesia. In specific cases, the patient is free to go home after the examination.
Ureteroscopy | Introduction
A urethral diverticulum is a condition where the urethra or the periurethral glands push into the connective tissue layers (fascia) that surround it.
Urethral diverticulum | Introduction
A ureterocele is a congenital abnormality found in the ureter. In this condition the distal ureter balloons at its opening into the bladder, forming a sac-like pouch. It is most often associated with a duplicated collection system, where two ureters drain their respective kidney instead of one. Simple ureterocele, where the condition involves only a single ureter, represents only twenty percent of cases. Ureterocele affects one in 4,000 individuals, at least four-fifths of whom are female. Patients are frequently Caucasian. Since the advent of the ultrasound, most ureteroceles are diagnosed prenatally. The pediatric and adult conditions are often found incidentally, i.e.
Ureterocele | Introduction
Due to the positions where the urethra exits the body, males and females often use different techniques for urination.
Urination | Techniques
Ectopic ureter (or ureteral ectopia) is a medical condition where the ureter, rather than terminating at the urinary bladder, terminates at a different site. In males this site is usually the urethra, in females this is usually the urethra or vagina. It can be associated with renal dysplasia, frequent urinary tract infections, and urinary incontinence (usually continuous drip incontinence). Ectopic ureters are found in 1 of every 2000–4000 patients, and can be difficult to diagnose, but are most often seen on CT scans. Ectopic ureter is commonly a result of a duplicated renal collecting system, a duplex kidney with 2 ureters.
Ectopic ureter | Introduction
If a partial cystectomy is performed, damage to the ureter may occur depending of the location of the tumor removed. This may require an additional procedure to repair.
Cystectomy | Urinary tract
Tobacco smoking is associated with an increased risk of ureteral cancer.
Ureteral cancer | Risk factors
In the developing embryo, at the hind end lies a cloaca. This, over the fourth to the seventh week, divides into a urogenital sinus and the beginnings of the anal canal, with a wall forming between these two inpouchings called the urorectal septum. The urogenital sinus divides into three parts, with the middle part forming the urethra; the upper part is largest and becomes the urinary bladder, and the lower part then changes depending on the biological sex of the embryo. The cells lining the urethra (the epithelium) come from endoderm, whereas the connective tissue and smooth muscle parts are derived from mesoderm.
Urethra | Development
All vertebrates have two kidneys located behind the abdomen that produce urine, and have a way of excreting it, so that waste products within the urine can be removed from the body. The structure specifically called the ureter is present in amniotes, meaning mammals, birds and reptiles. These animals possess an adult kidney derived from the metanephros. The duct that connects the kidney to excrete urine in these animals is the ureter. It connects to the urinary bladder, from whence urine leaves via the urethra.
Ureter | Other animals
Instruments used specially in Urology are as follows:
Instruments used in urology | Introduction
In the male the Müllerian ducts atrophy, but traces of their anterior ends are represented by the appendices testis (hydatids of Morgagni of the male), while their terminal fused portions form the utriculus in the floor of the prostatic urethra.
Development of the urinary system | Atrophy in males
Alternatively, Edwards (1982) proposed that the inner tissue of "Nematothallus" comprised stringy tubes, with the cellular patterning produced by their ends.
Nematothallus | History of research
Urethral rupture may be diagnosed with a cystourethrogram. Due to the tight adherence of the fascia lata, urine from a urethral rupture cannot spread into the thighs.
Urethral rupture | Introduction
Several forms of medical imaging exist that are used to view the ureters and urinary tract. Ultrasound may be able to show evidence of blockage because of hydronephrosis of the kidneys and renal pelvis. CT scans, including ones where contrast media is injected intravenously to better show the ureters, and with contrast to better show lesions, and to differentiate benign from malignant lesions. Dye may also be injected directly into the ureters or renal tract; an antegrade pyelogram is when contrast is injected directly into the renal pelvis, and a retrograde pyelogram is where dye is injected into the urinary tract via a catheter, and flows backwards into the ureters.
Ureter | Imaging
According to the American Urological Association, the diagnostic criteria are the following: Tissue for histological analysis is usually obtained via a transurethral resection of bladder tumor (TURBT).
Urachal cancer | Diagnosis
A ureterostomy is the creation of a stoma (a new, artificial outlet) for a ureter or kidney. The procedure is performed to divert the flow of urine away from the bladder when the bladder is not functioning or has been removed. Indications include bladder cancer, spinal cord injury, malfunction of the bladder, and birth defects such as spina bifida.
Ureterostomy | Introduction
Ureterocutaneostomy is a type of incontinent, cutaneous urinary diversion. It provides a basic urinary diversion for preventing ureteral obstruction. Ureterocutaneostomy is usually preferred in infants/children as a temporary diversion whose metabolic status is inadequate for reconstructive surgery or palliative care of bladder carcinoma patients. Main surgical technique involves dissection of ureter/ureters and creating a terminal or loop stoma to skin using ureter lumen. In case of bilateral obstruction, two ureter lumens can be connected using transureteroureterostomy technique or two separate stomas can be created.
Ureterocutaneostomy | Introduction
Invasive urothelial carcinoma is a type of transitional cell carcinoma. It is a type of cancer that develops in the urinary system: the kidney, urinary bladder, and accessory organs. Transitional cell carcinoma is the most common type of bladder cancer and cancer of the ureter, urethra, renal pelvis, the ureters, the bladder, and parts of the urethra and urachus. It originates from tissue lining the inner surface of these hollow organs - transitional epithelium. The invading tumors can extend from the kidney collecting system to the bladder. Carcinoma (from the Greek "karkinos", or "crab", and "-oma", "growth") is a type of cancer.
Invasive urothelial carcinoma | Introduction
The word "urethra" comes from the Ancient Greek stem "uro" relating to urination, with the structure described as early as the time of Hippocrates. Confusingly however, at the time it was called "ureter". Thereafter, terms "ureter" and "urethra" were variably used to refer to each other thereafter for more than a millennia. It was only in the 1550s that anatomists such as Bartolomeo Eustacchio and Jacques Dubois began to use the terms to specifically and consistently refer to what is in modern English called the ureter and the urethra. Following this, in the 19th and 20th centuries multiple terms relating to the structures such as urethritis and urethrography, were coined.
Urethra | History
The anatomical variation in membranous urethral length measurements in men have been reported to range from 0.5 cm to 3.4 cm.
Membranous urethra | Introduction
The corpus spongiosum is the mass of spongy tissue surrounding the male urethra within the penis. It is also called the corpus cavernosum urethrae in older texts.
Corpus spongiosum penis | Introduction
The clitoral crura (singular: clitoral crus) are two erectile tissue structures, which together form a V-shape. "Crus" is a Latin word that means "leg". Each "leg" of the "V" converges on the clitoral body. At each divergent point is a corpus cavernosum of clitoris. The crura are attached to the pubic arch, and are adjacent to the vestibular bulbs. The crura flank the urethra, urethral sponge, and vagina and extend back toward the pubis. Each clitoral crus connects to the rami of the pubis and the ischium. During sexual arousal, the crura become engorged with blood, as does all of the erectile tissue of the clitoris.
Crus of clitoris | Introduction
The urethra lies very near the last part of the intestine. Digestive system: The jaw has numerous ribs. Radula with tricuspid central tooth with square basal plate, as large as the bicuspid laterals, the marginals multicuspid. Reproductive system: Ovotestis forms two groups of follicles. Penis is continued in a long epiphallus and bears a long appendix, with swollen basal and distal divisions, the penial retractor bifurcate, one branch inserted on the epiphallus, the other on the base of the appendix (distally it attaches to the right ocular retractor, according to G. Dallas Hanna).
Strobilopsidae | Anatomy
perversus" is not present in the Natuna Islands. Carl Arend Friedrich Wiegmann (1893, 1898) discussed portions of the anatomy of "A. adamsii", "A. porcellanus", "A. contrarius", and "A. sinistralis". Walter Edward Collinge (1901, 1902) briefly noted features of "A. palaceus" and "A. parakensis" (reported as "A. perversus"). Haniel (1921) dissected "A. contrarius" and "A. reflexilabris", and Bernhard Rensch published a few scattered notes in his various faunistic surveys. A few earlier notes are mentioned in Pilsbry (1900). Characters such as the long, narrow kidney with reflexed ureter and closed secondary ureter, the penial complex with distinct penis, which is continuous with the epiphallus, epiphallic caecum (a flagellum and an appendix), unbranched gametolytic duct, lack of vaginal accessory organs, and the basic condition of the nervous and retractor muscle systems support the inclusion of "Amphidromus" in the family Camaenidae.
Amphidromus | Anatomy
Uroleptus musculus is a species of ciliates.
Uroleptus musculus | Introduction
For a time the vagina is represented by a solid rod of epithelial cells. A ring-like outgrowth of this epithelium occurs at the lower end of the uterus and marks the future vaginal fornix. At about the fifth or sixth month the lumen of the vagina is produced by the breaking down of the central cells of the epithelium. The hymen represents the remains of the Müllerian eminence.
Development of the urinary system | Development in females
Urogenital tuberculosis may cause strictures of the ureter, which, however, may heal when infection is treated.
Urogenital tuberculosis | Complications
A ureteral stent (pronounced you-REE-ter-ul), or ureteric stent, is a thin tube inserted into the ureter to prevent or treat obstruction of the urine flow from the kidney. The length of the stents used in adult patients varies between 24 and 30 cm. Additionally, stents come in differing diameters or gauges, to fit different size ureters. The stent is usually inserted with the aid of a cystoscope. One or both ends of the stent may be coiled to prevent it from moving out of place; this is called a JJ stent, double J stent or pig-tail stent.
Ureteric stent | Introduction
Part of the renal cortex, a medullary ray is a collection of renal tubules that drain into a single collecting duct. The tip, or papilla, of each pyramid empties urine into a minor calyx; minor calyces empty into major calyces, and major calyces empty into the renal pelvis. This becomes the ureter. At the hilum, the ureter and renal vein exit the kidney and the renal artery enters. Hilar fat and lymphatic tissue with lymph nodes surround these structures. The hilar fat is contiguous with a fat-filled cavity called the renal sinus. The renal sinus collectively contains the renal pelvis and calyces and separates these structures from the renal medullary tissue.
Kidney | Gross anatomy
The fibrous envelope of the corpus cavernosum urethrae is thinner, whiter in color, and more elastic than that of the corpora cavernosa penis. It is called the trabeculae of corpus spongiosum of penis. The trabeculae are more delicate, nearly uniform in size, and the meshes between them smaller than in the corpora cavernosa penis: their long diameters, for the most part, corresponding with that of the penis. The external envelope or outer coat of the corpus cavernosum urethrae is formed partly of unstriped muscular fibers, and a layer of the same tissue immediately surrounds the canal of the urethra.
Trabeculae of corpus spongiosum of penis | Introduction
The urethra (from Greek οὐρήθρα – "ourḗthrā") is a tube that connects the urinary bladder to the urinary meatus for the removal of urine from the body of both females and males. In human females and other primates, the urethra connects to the urinary meatus above the vagina, whereas in marsupials, the female's urethra empties into the urogenital sinus. Females use their urethra only for urinating, but males use their urethra for both urination and ejaculation. The external urethral sphincter is a striated muscle that allows voluntary control over urination. The internal sphincter, formed by the involuntary smooth muscles lining the bladder neck and urethra, receives its nerve supply by the sympathetic division of the autonomic nervous system.
Urethra | Introduction
Between 1988 and 2001 in the United States, cancer surveillance reports to SEER included 1,333 cases of ureteral cancer in adults: 808 male and 525 female, 1,158 white and 42 black. Of the total, 1,251 (94%) were transitional cell carcinoma of the papillary type. "Five-year relative survival rates from cancers of the ureter were similar among males vs. females..."
Ureteral cancer | Epidemiology
A urinary diversion is then created and the free ends of the ureters are reconnected to the diversion.
Cystectomy | Open
Cavernous tissue refers to blood-filled spaces lined by endothelium and surrounded by smooth muscle. It is present in the erectile tissue of the penis and clitoris.
Cavernous tissue | Introduction