Urinary incontinence is defined as the involuntary loss of urine. There are mainly three types of incontinence: stress incontinence, urge incontinence and overflow incontinence.
1.Stress Incontinence
Stress urinary incontinence (SUI) is defined as the involuntary loss of urine during effort or exertion or during sneezing or coughing. It has been estimated that 10 to 30% of adult women are affected by SUI. It severely affects every facet of the patients’ life – work, home, social, physical, sexual and psychological.
In female SUI is most often caused by pelvic floor muscle laxity as a result of repeated childbirth. As a result of the laxity there is loss of anatomical support to the bladder neck and the proximal urethra. During increase in intra-abdominal pressure the weakened anatomical support allow the bladder neck and proximal urethra to rotate downward and posteriorly. The resulting shearing force opens up the urethra and thus incontinence occurs. A less common cause of SUI is intrinsic sphincter deficiency in which the urethral sphincter is intrinsically weak, regardless of its anatomical position. ISD can result from previous surgery that damage urethral sphincter, neurological insult, radiation damage and aging.
Evaluation of patients with SUI should consist of structured micturition history, physical examination, micturition diary, pad test, urinalysis and culture, renal function test and urodyanamic study.
History is important in assessing the characteristics and severity of SUI as well as its impact on quality of life. It is also important in identifying risk factors or underlying causes for the incontinence.
Physical examination should focus on detecting anatomical and neurological abnormalities that contributes to the SUI. A vaginal examination should be performed to assess the tone of the pelvic floor muscle and also to check for pelvic organs prolapse. With the bladder comfortably full the patient is asked to cough or strain in an attempt to reproduce the stress urinary incontinence.
Micturition diary is useful in providing information on patient’s drinking and voiding patterns. Pad test provide a semi-objective measurement of urine loss over a given period of time.
Women in Hong Kong are becoming more aware of the condition of SUI and are more willing to seek medical advice for this condition as SUI significantly affect the quality of life. The treatment depends upon the nature and severity of the condition. With appropriate treatment most women could be cured of their incontinence problem.
2.Urge Incontinence
Urge incontinence is the involuntary loss of urine associated with a strong desire to void. It is caused by the presence of involuntary detrusor contraction.The involuntary detrusor contraction may be idiopathic(overactive bladder) or secondary to infection, urinary tract stones or bladder tumour.
3.Overflow Incontinence
A history of continuous loss of urine suggests overflow incontinence. It happens when small amount of urine leaks from a bladder that is constantly full. It usually occurs in patients who cannot empty their bladder either as a result of bladder outlet obstruction (eg. benign prostatic hyperplasia) or bladder acontractility.