Intrinsic sphincter deficiency is associated with female stress incontinence as a common contributing factor.
Currently defined by the International Continence Society as “the complaint of involuntary loss of urine on effort or physical exertion”, stress incontinence affects 22% of women aged 45 to 64 years.
Are you suffering from stress incontinence? Read our guidance on managing stress incontinence for advice.
Experts often disagree on the meaning of the term “intrinsic sphincter deficiency”. There is no laboratory method to diagnose ISD precisely, which makes it hard to develop a specific definition. In summary, people with intrinsic sphincter deficiency have a combination of urethral anatomic and physiologic factors that fail to prevent stress urinary incontinence, despite having urethrovesical junction support. The bladder neck and urethra do not have sufficient pressure resistance necessary to prevent escape of urine, despite the absence of a bladder contraction. It should be suspected in women with stress incontinence for an early diagnosis. If ISD is not diagnosed before surgery, it creates a huge risk for further complication.
In summary, the key features of Intrinsic Sphincter Deficiency are the following:
– a lack of urethral mobility
– the presence of stress incontinence
– there is no detrusor contraction at the time of leakage
In those with ISD, the urethra completely loses its ability to maintain a watertight seal. In this case, the urethral sphincter is unable to generate enough resistance to retain urine in the bladder. People with this condition can often struggle severely, leaking urine at low volumes and pressures with minimal exertion. Records show that intrinsic sphincter deficiency is very often associated with multiple incontinence surgical procedures in women, as well as hypoestrogenism.
Interestingly, evidence has shown that accidents are more frequent in cases of ISD than in cases of stress urinary incontinence without ISD. Stress incontinence with ISD is also much less common than stress incontinence without the condition.
What is Intrinsic Sphincter Deficiency Caused by?
Intrinsic Sphincter Deficiency occurs when there is a weakness of the urethral sphincter. It is often caused by genetics, nerve damage from surgery or neurological conditions such as Parkinson’s Disease.
It can also be caused by:
-A vaginal birth
Treating Intrinsic Sphincter Deficiency
Treatment for intrinsic sphincter deficiency should be focused on increasing urethral resistance. Adequate intrinsic urethral resistance is much more useful than the correction of urethral hypermobility in those with intrinsic sphincter deficiency.
Popular treatment methods for intrinsic sphincter deficiency include sling procedures, injections and artificial sphincters. The suburethral sling procedure is the most widely accepted definitive therapy for intrinsic sphincter deficiency. If you are a poor candidate of surgery however, periurethral injection therapy is a popular alternative. Intrinsic sphincter deficiency is frequently treated with collagen bulking at the bladder neck. A study in 2001 evaluated the effectiveness of bulking agents to treat intrinsic sphincter deficiency. Incontinence grading indicated 16 patients dry, and 10 improved at 12 months for a total of 26 of 32 dry and improved after one treatment. Only four patients had a 12 month pad weight test over 2.2g. Quality of life scores improved significantly after treatment.
Artificial urinary sphincter is another popular treatment method for intrinsic sphincter deficiency. An artificial sphincter has a cuff, pump and fluid-filled reservoir. The cuff is placed around your urethra, squeezing it so urine does not leak out. The pump is placed underneath the skin next to the vagina. To pass urine, you simply squeeze the pump. In general, patients have high satisfaction and gain continence with the device. However, it is currently offered only in centres with expertise in stress incontinence.
52 year old Andrea is one of the many women who suffer from intrinsic sphincter deficiency. She asserts, “many years ago, I noticed I leaked urine during physical exertion. If I lifted something heavy in the warehouse at work, I would leak a few drops of urine. My friend recommended me a pad specially designed for light incontinence, which made my experience much less embarrassing. My Doctor found I had intrinsic sphincter deficiency. He suggested a suburethral sling procedure and this honestly turned my life around”.
You can shop our light and stress incontinence products here for protection against leaks caused by ISD.