The urethra is the tube that connects the mammalian urinary bladder to the urinary meatus. In placental mammals, the urethra transports urine through the penis or vulva during urination and semen through the penis during ejaculation.
The prostate is both an accessory gland of the male reproductive system and a muscle-driven mechanical switch between urination and ejaculation. It is found in all male mammals. It differs between species anatomically, chemically, and physiologically. Anatomically, the prostate is found below the bladder, with the urethra passing through it. It is described in gross anatomy as consisting of lobes and in microanatomy by zone. It is surrounded by an elastic, fibromuscular capsule and contains glandular tissue, as well as connective tissue.
The human urinary system, also known as the urinary tract or renal system, consists of the kidneys, ureters, bladder, and the urethra. The purpose of the urinary system is to eliminate waste from the body, regulate blood volume and blood pressure, control levels of electrolytes and metabolites, and regulate blood pH. The urinary tract is the body's drainage system for the eventual removal of urine. The kidneys have an extensive blood supply via the renal arteries which leave the kidneys via the renal vein. Each kidney consists of functional units called nephrons. Following filtration of blood and further processing, wastes exit the kidney via the ureters, tubes made of smooth muscle fibres that propel urine towards the urinary bladder, where it is stored and subsequently expelled through the urethra during urination. The female and male urinary system are very similar, differing only in the length of the urethra.
Urinary incontinence (UI), also known as involuntary urination, is any uncontrolled leakage of urine. It is a common and distressing problem, which may have a large impact on quality of life. It has been identified as an important issue in geriatric health care. The term enuresis is often used to refer to urinary incontinence primarily in children, such as nocturnal enuresis. UI is an example of a stigmatized medical condition, which creates barriers to successful management and makes the problem worse. People may be too embarrassed to seek medical help, and attempt to self-manage the symptom in secrecy from others.
A urethral stricture is a narrowing of the urethra, the tube connected to the bladder that allows urination. The narrowing reduces the flow of urine and makes it more difficult or even painful to empty the bladder.
Hypospadias is a common malformation in fetal development of the penis in which the urethra does not open from its usual location on the head of the penis. It is the second-most common birth defect of the male reproductive system, affecting about one of every 250 males at birth, although when including milder cases, is found in up to 4% of newborn males. Roughly 90% of cases are the less serious distal hypospadias, in which the urethral opening is on or near the head of the penis (glans). The remainder have proximal hypospadias, in which the meatus is all the way back on the shaft of the penis, near or within the scrotum. Shiny tissue or anything that typically forms the urethra instead extends from the meatus to the tip of the glans; this tissue is called the urethral plate.
Urinary retention is an inability to completely empty the bladder. Onset can be sudden or gradual. When of sudden onset, symptoms include an inability to urinate and lower abdominal pain. When of gradual onset, symptoms may include loss of bladder control, mild lower abdominal pain, and a weak urine stream. Those with long-term problems are at risk of urinary tract infections.
In medicine or biology, a diverticulum is an outpouching of a hollow structure in the body. Depending upon which layers of the structure are involved, diverticula are described as being either true or false.
Vaginectomy is a surgery to remove all or part of the vagina. It is one form of treatment for individuals with vaginal cancer or rectal cancer that is used to remove tissue with cancerous cells. It can also be used in gender-affirming surgery. Some people born with a vagina who identify as trans men or as nonbinary may choose vaginectomy in conjunction with other surgeries to make the clitoris more penis-like (metoidioplasty), construct of a full-size penis (phalloplasty), or create a relatively smooth, featureless genital area.
A urethrotomy is an operation which involves incision of the urethra, especially for relief of a stricture. It is most often performed in the outpatient setting, with the patient (usually) being discharged from the hospital or surgery center within six hours from the procedure's inception.
Posterior urethral valve (PUV) disorder is an obstructive developmental anomaly in the urethra and genitourinary system of male newborns. A posterior urethral valve is an obstructing membrane in the posterior male urethra as a result of abnormal in utero development. It is the most common cause of bladder outlet obstruction in male newborns. The disorder varies in degree, with mild cases presenting late due to milder symptoms. More severe cases can have renal and respiratory failure from lung underdevelopment as result of low amniotic fluid volumes, requiring intensive care and close monitoring. It occurs in about one in 8,000 babies.
The lacrimal caruncle, or caruncula lacrimalis, is the small, pink, globular nodule at the inner corner of the eye. It consists of tissue types of neighbouring eye structures. It may suffer from lesions and allergic inflammation.
Urethral cancer is a rare cancer originating from the urethra. The disease has been classified by the TNM staging system and the World Health Organization.
Obstructive uropathy is a structural or functional hindrance of normal urine flow, sometimes leading to renal dysfunction.
The urethral sphincters are two muscles used to control the exit of urine in the urinary bladder through the urethra. The two muscles are either the male or female external urethral sphincter and the internal urethral sphincter. When either of these muscles contracts, the urethra is sealed shut.
A caruncle is defined as 'a small, fleshy excrescence that is a normal part of an animal's anatomy'. Within this definition, caruncles in birds include wattles, combs, snoods, and earlobes. The term caruncle is derived from Latin caruncula, the diminutive of carō, "flesh".
A urethral diverticulum is a condition where the urethra or the periurethral glands push into the connective tissue layers (fascia) that surround it.
A urethral bulking injection is a gynecological procedure and medical treatment used to treat involuntary leakage of urine: urinary incontinence in women. Injectional materials are used to control stress incontinence. Bulking agents are injected into the mucosa surrounding the bladder neck and proximal urethra. This reduces the diameter of the urethra and creates resistance to urine leakage. After the procedure, the pressure forcing the urine from the bladder through the urethra is resisted by the addition of the bulking agent in the tissue surrounding the proximal urethra. Most of the time this procedure prevents urinary stress incontinence in women.
