What is Bladder Sphincter Dyssynergia?
The ability to control urination and remain continent relies on the well-functioning detrusor muscle (muscle in your bladder) and a competent urethral sphincter (ring-like muscle that controls the flow of urine). Normal urination involves two stages—a storage stage and a voiding or emptying stage. In the storage stage, the bladder fills up passively. During the voiding stage, there needs to be accurate coordination between the contraction of the detrusor muscle and the relaxation of the external and internal sphincters (ring-like muscles at the bladder’s exit).
The central nervous system, which includes the brain and spinal cord, regulates this intricate process of urination. It oversees the activity of the autonomic and somatic nervous systems, which control involuntary and voluntary body functions, respectively. Their coordination ensures normal control over urination and continence. Detrusor sphincter dyssynergia (DSD) is a term for various lower urinary tract symptoms. This condition occurs when the detrusor muscle contracts while the urethral sphincter also contracts inappropriately and involuntarily, disrupting normal urination.
What Causes Bladder Sphincter Dyssynergia?
DSD, or detrusor sphincter dyssynergia, results from damage in certain areas of the spinal cord, more specifically the suprasacral region. Various reasons such as spinal cord injury from an accident, disorders related to spinal cord development (myelodysplasia), multiple sclerosis, stroke, spinal cord infections, transverse myelitis (inflammation of the spinal cord), and birth defects such as neural tube defects, spina bifida, and spinal dysraphism could lead to this damage. More often, DSD is seen in people who have had spinal cord injuries, spina bifida, or multiple sclerosis.
DSD has been categorized into three types. Type 1 happens when the bladder muscle (detrusor) and the bladder outlet (sphincter) tighten at the same time. Once the bladder contraction reaches its peak, the bladder outlet suddenly relaxes, resulting in urination. In Type 2, the bladder outlet randomly tightens during the whole bladder contraction. Type 3 is when the bladder outlet’s contraction follows a pattern of increasing and decreasing during the entire bladder contraction, blocking the bladder opening throughout.
Researchers have further classified DSD into continuous or intermittent. The specific subtype of DSD a person may have seems to relate to the type and extent of their spinal cord injury. For example, people with damage at the cervical (neck level) of the spinal cord are more likely to develop DSD than those with damages at lower levels of the spinal cord. Those with incomplete neurological damage are commonly associated with Type 1 DSD, and those with complete neurological lesions may develop Type 2 or 3 DSD.
Risk Factors and Frequency for Bladder Sphincter Dyssynergia
Detrusor-Sphincter Dyssynergia (DSD) is a condition that can show up in almost any significant neurological disease, but the exact number of cases is unknown. Spinal Cord Injuries (SCI) are a common cause of DSD. These injuries often occur in younger people and are more common in males. DSD is found in about 75% of individuals who have had a suprasacral SCI. In patients with multiple sclerosis, about 35% may show signs of DSD when tested, and up to 50% of infants with spina bifida may experience this disorder.
Signs and Symptoms of Bladder Sphincter Dyssynergia
Patients with Detrusor Sphincter Dyssynergia (DSD) usually experience problems with their lower urinary tract, making it difficult to release or store urine. Some of the problems that might occur include long-term urinary retention, irregularities in urinating, or even involuntary leakage of urine without the feeling of needing to urinate, which is known as reflex incontinence. It’s also important to note that DSD is often linked to disorders of the central nervous system which can cause other neurological symptoms.
When doctors examine these patients, they aim to identify the cause and pattern of bladder issues, look for potential complications, and check for changes in bowel and bladder habits as well as related neurological symptoms. They will also look for signs of underlying neurological diseases and investigate if there are unexpected vision problems, back or neck pain, weakness, numb feelings, abnormal sensations, and unexplained urinary or bowel symptoms.
- Long-term urinary retention
- Irregularities in urinating
- Involuntary leakage of urine (reflex incontinence)
- Unexpected vision problems
- Back or neck pain
- Weakness
- Numb feelings
- Abnormal sensations
- Unexplained urinary or bowel symptoms
An essential part of the examination process involves assessing the abdomen to identify the presence of a noticeable bladder, retained fecal matter, tenderness, and signs of previous surgeries. They also inspect the genital area for any signs of disease or skin irritation. A digital rectal examination is performed to assess the muscle tone in the anus at rest and during voluntary contraction. Additionally, doctors also take note of sensation levels in the perineum and conduct other relevant reflex tests.
Testing for Bladder Sphincter Dyssynergia
The main goal of testing for bladder dysfunction is to accurately find out the root cause and any potential complications. Initially, doctors usually check for common symptoms related to the lower urinary tract. If they suspect a urinary tract infection, they will order a urine culture and sensitivity test. It’s also important to check the levels of urea and creatinine in the blood and measure electrolytes. A patient might be asked to keep a 24-hour diary to record when and how often they urinate. This can help provide more insights.
Imaging techniques, such as ultrasonography and computed tomography (CT) scans, can help further investigate complications including kidney swelling, urinary reflux, urinary stones, and residual urine left in the bladder after urinating. However, please note that these imaging results might not give a specific diagnosis of Detrusor Sphincter Dyssynergia (DSD), a condition of the urinary tract that occurs when the bladder muscle and the urethral sphincter malfunction and do not work together co-ordinately.
To diagnose DSD, doctors typically use a urodynamic study, which is a type of testing that measures how well your bladder and urethral sphincter are working. This can involve several techniques such as electromyography (EMG), voiding cystourethrogram, video urodynamics, and urethral pressure profile measurements. Sometimes, a procedure called a cystoscopy is done to rule out any narrowing of the urethra.
In EMG, doctors look for increased sphincter activity when the bladder muscle contracts. In a voiding cystourethrogram, the bladder neck appears closed during the filling phase but expands during urination up to the external urinary sphincter. A plateau or standstill in the bladder muscle pressure during urination may suggest DSD, but it’s not a definitive criterion and needs confirmation.
Urethral pressures are also used to help diagnose DSD. Doctors place a catheter with independent bladder and urethral pressure sensors at the site of the highest sphincter pressure in the proximal urethra. DSD is then defined as an abrupt increase in urethral pressure by more than 20 cm of water during or just before a bladder muscle contraction.
Treatment Options for Bladder Sphincter Dyssynergia
Before starting treatment, it’s important for the doctor and patient to agree on the main goals. These typically include preserving kidney function, ensuring patient safety, and enhancing quality of life. The main aim is to ensure that the bladder can store and release urine properly and safely, and without putting too much pressure on the inside of the bladder. Regular check-ups and tests are needed to make sure that the treatment is working effectively.
Type 1 DSD is usually just closely monitored without any specific treatment, unless there are complications such as kidney swelling, kidney damage, or some nerve disorders.
In treating DSD, medications play a limited role. Alpha-blockers such as tamsulosin which improve urine flow have been successfully used to reduce residual urine in the bladder and increase the volume of urine voided. Diazepam has also been used either by itself or in combination with alpha-blockers. However, there aren’t sufficient controlled studies to fully endorse its use.
Baclofen is a medicine traditionally used to treat muscle spasms. However, it does not easily pass the blood-brain barrier, meaning it does not reach the brain effectively. Because of this, it’s not very effective in treating DSD unless it’s directly delivered into the space around the spinal cord (intrathecal delivery). This method has shown some success, but it is considered invasive and labor-intensive.
Other drugs have been tried, including nitric oxide donors like glyceryl trinitrate, benzodiazepines, and dantrolene sodium. However, none of these are currently recommended as standard treatments. A drug called oxybutynin has been tested; it is thought to reduce uncontrolled contractions and improve the bladder’s holding capacity, but there is insufficient data to support its use.
A method called sacral neuromodulation could potentially be highly beneficial for treating DSD. This procedure uses an implanted device which sends mild electrical impulses to the sacral nerves, thought to control bladder function. However, more studies are needed to confirm its effectiveness.
Clean Intermittent Self-Catheterization (CISC) is a common treatment technique used alongside medications (antimuscarinics) to reduce bladder pressure and contractions. This method helps to regularly drain the bladder, even in the presence of a problematic sphincter. Antimuscarinics can cause side effects such as dry eyes, dry mouth, constipation, nausea, headaches, and cognitive impairments. Regular renal ultrasound can be used to monitor if this treatment is reducing kidney swelling. In cases where patients can’t carry out self-catheterization, indwelling catheters are recommended.
There are 3 different self-catheterization methods available, with the “clean” technique being most suitable for patients at home. The other 2 methods are generally used in medical facilities. However, it should be noted that all these methods come with some risks, such as potential urethral injury, scarring, bleeding, and threat of infection if not done properly.
When non-invasive treatments become ineffective, injections of botulinum toxin (Botox) into the urethra or bladder may be considered. Botulinum toxin works by blocking the release of a chemical messenger which initiates muscle contraction, thereby causing muscle relaxation. This treatment is quite effective when administered directly into the muscle controlling the bladder.
Historically, surgery was the standard treatment, but this approach may come with significant complications. There has been some success with minimally invasive techniques, such as balloon dilatation and temporary or permanent urethral stents. These are seen as safe and effective, with one obvious advantage of using a urethral stent being its reversibility. On the downside, there’s a risk of misplacement or it causing an obstruction in the bladder.
What else can Bladder Sphincter Dyssynergia be?
Patients with Detrusor Sphincter Dyssynergia (DSD) often experience a variety of lower urinary tract symptoms. However, before diagnosing DSD, it’s crucial to investigate and rule out other more typical causes of these symptoms. The common non-neurological causes for these urinary symptoms include:
- Bladder neck obstruction
- External sphincter spasticity
- Bladder neck and urethral strictures
- Dysfunctional voiding
- Pseudodyssynergia – the involuntary contraction of the external urethral sphincter during urination, which can often be mistaken for DSD
Pseudodyssynergia can be caused by straining the abdomen during a Valsalva maneuver (a technique of breathing), response to pain, or deliberately trying to stop a bladder contraction.
What to expect with Bladder Sphincter Dyssynergia
DSD, or Detrusor Sphincter Dyssynergia, can cause high pressure in the bladder, which may lead to backflow of urine towards the kidney, bladder damage, and various patterns of abnormal urination. If not treated, up to half of the patients with DSD might experience complications.
A study that combines the results of various other studies shows that the success rates can vary depending on the treatment methods, like:
* Injections of Botulinum A into the external part of the urinary muscle, called the sphincter. These have a success rate between 64% and 100%.
* Injections of Botulinum A into the bladder, with a success rate between 44% and 76%.
* Drug treatments, which also have a success rate between 44% and 76%.
* Sphincterotomy, which is a surgical procedure to cut the sphincter muscle. This technique has been successful in 48% to 85% of instances.
* Transurethral incision of the bladder neck, a surgical method with a high success rate up to 82%.
* Sacral neuromodulation, a treatment that involves the use of electrical impulses to the nerves controlling the bladder, which has a 60% success rate.
* Urethral stents, a treatment that places a small tube inside the urethra to keep it open, with a wide range of reported success rates between 9% and 91%.
Possible Complications When Diagnosed with Bladder Sphincter Dyssynergia
The consequences of not treating DSD can be severe and affect many areas of your urinary system.
Patients leaving DSD untreated might face a variety of health problems. Up to half of these patients could experience serious urinary-related complications. Women are less likely than men to experience these complications because the bladder muscles in women, known as detrusor muscles, generate less internal pressure.
If not treated, DSD can lead to several unpleasant ailments. These include urinary tract infections (UTIs), blood infection from a UTI (urosepsis), backflow of urine from bladder to kidney (vesicoureteric reflux), kidney swelling from a blockage in urine flow (hydronephrosis), damage to the upper urinary tract, kidney functionality impairment (renal insufficiency), stone formation in the urinary system (urolithiasis), and damage to the bladder.
You may also experience complications due to the medical treatment used in addressing DSD.
Below is the list of potential complications:
- Severe urological complications
- Urinary tract infections (UTIs)
- Urosepsis (blood infection originating from a UTI)
- Vesicoureteric reflux (backflow of urine from bladder to kidney)
- Hydronephrosis (kidney swelling due to a blockage in the urine flow)
- Upper urinary tract damage
- Renal insufficiency (impaired kidney function)
- Urolithiasis (stone formation in the urinary system)
- Bladder damage
- Complications from DSD treatment
Preventing Bladder Sphincter Dyssynergia
It’s vital to educate patients about DSD (Detrusor Sphincter Dyssynergia) to enhance their understanding and help them feel more in control of their health. DSD refers to a condition where the bladder muscle and the urinary sphincter (the muscle controlling urine flow out of the bladder) don’t work together properly, which can cause issues with urination. By clearly explaining this to patients, they can understand the importance of early detection and the right management of DSD to maintain a good quality of life.
It’s also essential for patients to be familiar with the different treatment options available for DSD, such as exercises, medications, or using a catheter (a thin tube inserted into the bladder to drain urine). This knowledge allows patients to be actively involved in making decisions about their care. By making them aware of possible complications like UTIs (Urinary Tract Infections), and the importance of sticking to their treatment plans, patients can take actions to reduce the potential risks linked with DSD.
Educating patients about DSD can help relieve their worries by helping them understand the neurological basis – or the brain and nerve related cause – of their condition. Moreover, it emphasizes that their healthcare providers are there to support them in improving their urinary function and enhancing their overall health and well-being.
