The urinary bladder is the organ that collects urine excreted by the kidneys prior to disposal by urination. Urine enters the bladder via the ureters and exits via the urethra.
Anatomy
The urinary bladder is a hollow, muscular and distensible organ that sits on the pelvic floor (superior to the prostate in males). On its anterior border lies the pubic symphysis and, on it’s posterior border, the vagina (in females) and rectum (in males). The urinary bladder is normally capable of storing 1.1-1.3 liters of urine, but because it is made up of transitional epithelium it is able to stretch to volumes of even several liters.
The ureters enter the bladder diagonally from its dorsolateral floor in an area called the trigone. The trigone is a triangular shaped area on the posteroinferior wall of the bladder. The urethra exits at the lowest point of the triangle of the trigone
Detrusor muscle
The detrusor muscle is a layer of the urinary bladder wall, made up of smooth muscle fibers arranged in inner and outer longitudinal layers and a middle circular layer. Contraction of the detrusor muscle causes the bladder to expel urine through the urethra. Problems with this muscle can lead to incontinence.
Diseases of the bladder
- Bladder sphincter dyssynergia, a condition where the sufferer cannot coordinate relaxation of the urethra sphincter with the contraction of the bladder muscles
- Cystitis-Cystitis is the inflammation of the bladder. The condition primarily affects women, but can affect all age groups from either sex. There are several types of cystitis:
Bacterial cystitis (most common)
Interstitial cystitis, which is rare, difficult to diagnose, and does not involve foreign organisms
Hemorrhagic cystitis
The main cause of bacterial cystitis (or urinary tract infection) is coliform bacteria. These bacteria commonly occupy the bowel, and may become transferred to the urethra, then the bladder, and cause cystitis. An antibiotic is the initial treatment for bacterial cystitis and drinking lots of water. - Cystolithiasis
- Cancer of the urinary bladder: bladder cancer
- Hematuria-is the presence of blood in the urine. It is a sign of a large number of diseases of the kidneys and the urinary tract, ranging from trivial to lethal. Occasionally "hemoglobinuria" is used synonymously, although more precisely it only refers to hemoglobin in the urine. Red discoloration of the urine can have various causes:
· Blood
· Microscopic hematuria (small amounts of blood, can only be seen on urinalysis or light microscopy)
· Macroscopic (or "frank" or "gross") hematuria
· Hemoglobin (only the red pigment, not the red blood cells)
· Other pigments (e.g. porphyrins in porphyria) - Interstitial cystitis-Interstitial cystitis (commonly abbreviated to "IC") is a urinary bladder disease of unknown cause characterized by pelvic and intense bladder pain, urinary frequency (as often as every 10 minutes), pain with sexual intercourse, and often pain with urination. It is not unusual for patients to experience nocturia and pain with sexual intercourse. IC is also known as painful bladder syndrome (PBS), particularly outside of the USA.
- Ureterocele
- Urinary bladder dysfunction
- Urinary incontinence
Urinary incontinence
Urinary incontinence is the involuntary excretion of urine from one's body. It is often temporary, and it almost always results from an underlying medical condition. Women experience incontinence twice as often as men. Pregnancy and childbirth, menopause, and the structure of the female urinary tract account for this difference. But both women and men can become incontinent from neurologic injury, birth defects, strokes, multiple sclerosis, and physical problems associated with aging. While urinary incontinence affects older women more often than younger women. Incontinence is treatable and often curable at all ages.
Types of incontinence
Stress incontinence
Stress incontinence is incontinence that is caused by actions such as coughing, laughing, sneezing, exercising or other movements that increase intraabdominal pressure and thus increase pressure on the bladder. Physical changes resulting from pregnancy, childbirth, and menopause often cause stress incontinence. It is the most common form of incontinence in women and is treatable.
Urge incontinence
Urge incontinence is involuntary loss of urine occurring for no apparent reason while suddenly feeling the need or urge to urinate. The most common cause of urge incontinence is inappropriate bladder contractions. Medical professionals describe such a bladder as "unstable," "spastic," or "overactive." It may also be called "reflex incontinence" if it results from overactive nerves controlling the bladder. Involuntary actions of bladder muscles can occur because of damage to the nerves of the bladder, to the nervous system (spinal cord and brain), or to the muscles themselves. Multiple sclerosis, Parkinson's disease, Alzheimer's disease, stroke, and injury--including injury that occurs during surgery--all can harm bladder nerves or muscles.
Functional incontinence
People with functional incontinence may have problems thinking, moving, or communicating that prevent them from reaching a toilet.
Overflow incontinence
Overflow incontinence occurs when the patient's bladder is always full so that it frequently leaks urine. Weak bladder muscles or a blocked urethra can cause this type of incontinence.
Other types of incontinence
Stress and urge incontinence often occur together in women. Combinations of incontinence - and this combination in particular - are sometimes referred to as "mixed incontinence."
"Transient incontinence" is a temporary version of incontinence. It can be triggered by medications, urinary tract infections, mental impairment, restricted mobility, and stool impaction (severe constipation), which can push against the urinary tract and obstruct outflow.
Diagnosis of incontinence
A careful history taking is essential especially in the pattern of voiding and urine leakage as it suggests the type of incontinence faced. Other important points include straining and discomfort, use of drugs, recent surgery, and illness. The test often performed is the measurement of bladder capacity and residual urine for evidence of poorly functioning bladder muscles.
Other tests include:
Stress test - the patient relaxes, then coughs vigorously as the doctor watches for loss of urine.
Urinalysis - urine is tested for evidence of infection, urinary stones, or other contributing causes.
Blood tests - blood is taken, sent to a laboratory, and examined for substances related to causes of incontinence.
Ultrasound - sound waves are used to "see" the kidneys, ureters, bladder, and urethra.
Cystoscopy - a thin tube with a tiny camera is inserted in the urethra and used to see the inside of the urethra and bladder.
Urodynamics - various techniques measure pressure in the bladder and the flow of urine.
Treatment of incontinence
Exercises
Kegel exercises to strengthen or retrain pelvic floor muscles and sphincter muscles can reduce or cure stress leakage.
Electrical stimulation
Brief doses of electrical stimulation can strengthen muscles in the lower pelvis in a way similar to exercising the muscles. Electrodes are temporarily placed in the vagina or rectum to stimulate nearby muscles. This will stabilize overactive muscles and stimulate contraction of urethral muscles. Electrical stimulation can be used to reduce both stress incontinence and urge incontinence.
Biofeedback
Biofeedback uses measuring devices to help you become aware of your body's functioning. By using electronic devices or diaries to track when your bladder and urethral muscles contract, you can gain control over these muscles.
Timed voiding or bladder training
Timed voiding (urinating) and bladder training are techniques that use biofeedback. In timed voiding, you fill in a chart of voiding and leaking. From the patterns that appear in your chart, you can plan to empty your bladder before you would otherwise leak.
Medications
Medications can reduce many types of leakage. Some drugs inhibit contractions of an overactive bladder. Others relax muscles, leading to more complete bladder emptying during urination. Some drugs tighten muscles at the bladder neck and urethra, preventing leakage. And some, especially hormones such as estrogen, are believed to cause muscles involved in urination to function normally.
Pessaries
A pessary is a medical device that is inserted into the vagina. The most common kind is ring shaped, and is typically recommended to correct vaginal prolapse. The pessary compresses the urethra against the symphysis pubis and elevates the bladder neck. For some women this may reduce stress leakage.
Implants
Implants are substances injected into tissues around the urethra. The implant adds bulk and helps to close the urethra to reduce stress incontinence.
Surgery
Doctors usually suggest surgery to alleviate incontinence only after other treatments have been tried. Many surgical options have high rates of success.
Most stress incontinence results from the bladder dropping down toward the vagina. Therefore, common surgery for stress incontinence involves pulling the bladder up to a more normal position. Working through an incision in the vagina or abdomen, the surgeon raises the bladder and secures it with a string attached to muscle, ligament, or bone.
Catheterization
If you are incontinent because your bladder never empties completely (overflow incontinence) or your bladder cannot empty because of poor muscle tone, past surgery, or spinal cord injury, you might use a catheter to empty your bladder. A catheter is a tube that you can learn to insert through the urethra into the bladder to drain urine. Catheters may be used once in a while or on a constant basis, in which case the tube connects to a bag that you can attach to your leg.
Bladder cancer
Bladder cancer refers to any of several types of malignant growths of the urinary bladder. It is a disease in which abnormal cells multiply without control in the bladder. The bladder is a hollow, muscular organ that stores urine; it is located in the lower abdomen. The most common type of bladder cancer begins in cells lining the inside of the bladder (epithelial cells) and is called transitional cell carcinoma (TCC).
The greatest risk factor for bladder cancer is a genetic predisposition; it is also associated with smoking and occupational exposure to aniline-based dyes (such as in textile factories), as well as with petrol and other chemicals.
Signs and symptoms-Bladder cancer may cause blood in the urine, pain during urination, frequent urination, or feeling the need to urinate without results.
Treatment
The treatment of bladder cancer depends on how deep the tumor invades into the bladder wall. Superficial tumors (those not entering the muscle layer) can be "shaved off" using an electrocautery device. Tumors which infiltrate the bladder require more radical surgery where part or all of the bladder is removed and the urinary stream is diverted. Radiation can also be used to treat this disease.
Immunotherapy in the form of BCG instillation is also used to treat and prevent the recurrence of superficial tumors.
Genetics
The FGFR3, HRAS, RB1 and TP53 genes are associated with bladder cancer. As with most cancers, the exact causes of bladder cancer are not known; however, many risk factors are associated with this disease. Chief among them are smoking and exposure to industrial chemicals.
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