Detrusor: From 1 Different Sources
n. the muscle of the urinary bladder wall. The functioning of the detrusor and urethral sphincter is assessed by a urodynamic investigation (see urodynamics). This is used to diagnose dysfunction, absent and exaggerated reflexes, and overactivity of the muscle (detrusor instability, overactive bladder syndrome). Neurogenic detrusor overactivity is due to neurological damage, as occurs in multiple sclerosis or in suprasacral spinal cord injury.
Urinary incontinence The International Continence Society de?nes urinary incontinence as an involuntary loss of URINE that is objectively shown and is a social and hygiene problem. The elderly suffer most from this disorder because the e?ectiveness of the sphincter muscles surrounding the URETHRA declines with age. Men are less often affected than women; 20 per cent of women over 40 years of age have problems with continence. It is estimated that around three million people are regularly incontinent in the UK, a prevalence of about 40 per 1,000 adults.
Incontinence can be divided broadly into two groups: stress incontinence and incontinence due to an overactive URINARY BLADDER – also called detrusor instability – which affects one-third of incontinent women, prevalence increasing with age. Bladder symptoms do not necessarily correlate with the underlying diagnosis, and accurate diagnosis may require urodynamic studies – examination of urine within, and the passage of urine through and from, the urinary tract. However, such studies are best deferred until conservative treatment has failed or when surgery is planned.
Incontinence causes embarassment, inconvenience and distress in women, and men are reluctant to seek advice for what remains a social taboo for most people. Su?erers should be encouraged to seek help early and to discuss their anxieties and problems frankly. Often it is a condition which can be managed e?ectively at primary care centres, and quite simple measures can greatly improve the lives of those affected. STRESS INCONTINENCE is the most common cause of urinary incontinence in women. This is the involuntary loss of urine during activities that raise the intra-abdominal pressure, such as sneezing, coughing, laughing, exercise or lifting. The condition is caused by injury or weakness of the urethral sphincter muscle; this weakness may be either congenital or the result of childbirth, PROLAPSE of the VAGINA, MENOPAUSE or previous surgery. A CYSTOCOELE may be present. Urinary infection may cause incontinence or aggravate the symptoms of existing incontinence.
The ?rst step is to diagnose and treat infection, if present. Patients bene?t from simple advice on incontinence pads and garments, and on ?uid intake. Those with a high ?uid intake should restrict this to a litre a day, especially if frequency is a problem. Constipation should be treated and smoking stopped. The use of DIURETICS should be reduced if possible, or stopped entirely. Postmenopausal women may bene?t from oestrogen-replacement therapy; elderly people with chronic incontinence may need an indwelling urethral catheter.
Pelvic-?oor exercises can be successful and the insertion of vaginal cones can be a useful subsidiary treatment, as can electrical stimulation of the pelvic muscles. If these procedures are unsuccessful, then continence surgery may be necessary. The aim of this is to raise the neck of the bladder, support the mid part of the urethra and increase urethral resistance. Several techniques are available. URGE INCONTINENCE An overactive or unstable bladder results in urge incontinence, also known as detrusor incontinence – the result of uninhibited contractions of the detrusor muscle of the bladder. The bladder contracts (spontaneously or on provocation) during the ?lling phase while the patient attempts to stop passing any urine. Hyperexcitability of the muscle or a disorder of its nerve supply are likely causes. The symptoms include urgency (acute wish to pass urine), frequency and stress incontinence. Diagnosis can be con?rmed with CYSTOMETRY. Bladder training is the ?rst step in treatment, with the aim of reducing the frequency of urination to once every three to four hours. BIOFEEDBACK, using visual, auditory or tactile signals to stop bladder contractions, will assist the bladder training. Drug treatments such as CALCIUM-CHANNEL BLOCKERS, antimuscarinic agents (see ANTIMUSCARINE), TRICYCLIC ANTIDEPRESSANT DRUGS, and oestrogen replacement can be e?ective. Surgery is rarely used and is best reserved for di?cult cases. OVERFLOW INCONTINENCE Chronic urinary retention with consequent over?ow – more common in men than in women. The causes include antispasmodic drugs, continence surgery, obstruction from enlargement and post-prostatectomy problems (in men), PSYCHOSIS, and disease or damage to nerve roots arising from the spinal cord. Urethral dilatation or urethrotomy may be required when obstruction is the cause. Management is intermittent selfcatheterisation or a suprapubic catheter and treatment of any underlying cause.
Faecal incontinence is the inability to control bowel movements and may be due to severe CONSTIPATION, especially in the elderly; to local disease; or to injury or disease of the spinal cord or nervous supply to rectum and anal muscles. Those with the symptom require further investigation.... incontinence
This is the triangular basement muscle of the urinary bladder. It differs in structure and nerves from the top of the bladder, the detrusor muscle, which expands as the bladder fills, and contracts during urination under parasympathetic nerve stimulus. The trigone does not expand, is under sympathetic nerve stimulus, and supplies the rigidity and sphincter support for the urethra in front and the ureters in back.... trigone
(bladder outlet obstruction) a condition in which urine flow from the bladder through the urethra is impeded. It is usually caused by an enlarged *prostate gland but also by a high bladder neck or uncoordinated contraction of the urinary sphincter and detrusor muscle of the bladder.... boo
(LUTS) symptoms occurring during urine storage, voiding, or immediately after. These include *frequency, *urgency, *nocturia, *incontinence, *hesitation, *intermittency, *terminal dribble, *dysuria, and *postmicturition dribble. These symptoms used to be known as prostatism. Sometimes they are due to benign prostatic hyperplasia (see prostate gland), but they may be due to *detrusor overactivity, excessive drinking, diuresis due to poorly controlled diabetes, or a urethral stricture.... lower urinary tract symptoms
n. 1. (urinary bladder) a sac-shaped organ that has a wall of smooth muscle and stores the urine produced by the kidneys. Urine passes into the bladder through the *ureters; the release of urine from the bladder is controlled by a sphincter at its junction with the *urethra. The bladder neck is the outlet of the bladder where it joins the urethra and in males it is in contact with the *prostate gland; it is under the control of the autonomic nerves of the pelvis. The neck of the bladder is the commonest site for *retention of urine, usually by an enlarged prostate or a urethral *stricture. See also detrusor. 2. any of several other hollow organs containing fluid, such as the *gall bladder.... bladder
a powerful nerve toxin, produced by the bacterium Clostridium botulinum, that has proved effective, in minute dosage, for the treatment of various conditions of muscle dysfunction, such as dystonic conditions (see dystonia), including *torticollis and spasm of the orbicularis muscle in patients with *blepharospasm, and spastic paralysis associated with cerebral palsy and stroke. It is also used for the treatment of severe *hyperhidrosis and the prevention of chronic migraine headaches. The toxin may also be used to treat *achalasia, being injected through an endoscope into the gastro-oesophageal sphincter, and is used in the bladder to treat urinary incontinence due to *detrusor overactivity (as in multiple sclerosis) that is resistant to other treatments. Side-effects include prolonged local muscle paralysis. Under the trade names Botox and Dysport it is widely used for the cosmetic treatment of facial wrinkles.... botulinum toxin
see detrusor.... overactive bladder syndrome
n. an *antimuscarinic drug used to reduce frequency and urgency of passing urine associated with an instability of the *detrusor muscle of the bladder wall. It acts by reducing spontaneous detrusor activity and decreasing detrusor pressure. Side-effects include a dry mouth, loss of appetite, constipation, and blurred vision.... oxybutynin
n. an *antimuscarinic drug administered to relieve urinary frequency, urgency, and incontinence due to overactivity of the *detrusor muscle of the bladder. It has few side-effects.... solifenacin
n. an *antimuscarinic drug taken to treat *detrusor overactivity giving rise to the *lower urinary tract symptoms of frequency, urgency, or urge incontinence.... tolterodine
an *antimuscarinic drug indicated for the treatment of overactivity of the bladder *detrusor muscle with symptoms of urge incontinence, urgency, and frequency. The most common side-effects are dry mouth and constipation.... trospium chloride
n. the investigation of the function of the lower urinary tract. It involves the recording of pressures within the bladder during filling and voiding by the use of special equipment that can also record urethral sphincter pressures. Simultaneously, abdominal pressure is usually recorded with a catheter in the rectum, vagina, or ileal conduit. It is an essential investigation in the study of urinary incontinence. In some men, urodynamic studies are necessary to determine if their *lower urinary tract symptoms are caused by bladder outlet obstruction or *detrusor instability.... urodynamics
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