Today, we're talking about a type of bladder dysfunction called neurogenic bladder. We've asked one of our physician assistants, Bradley Hunt, to answer questions about this condition.

As with all content on the GBU blog, the following is meant to be educational, not medical advice. Always talk to a physician about your unique health care needs.

What is neurogenic bladder, and who does it affect? 

BRADLEY HUNT: In a broad sense, a neurogenic bladder is simply a bladder that does not contract. To successfully void, the detrusor (bladder) muscle must squeeze to increase the pressure within the bladder. Urine will then flow from an area of high pressure to an area of low pressure. 

A neurogenic bladder cannot create sufficient pressure to excrete the urine. Neurogenic bladder can affect anyone, but it is more common as we age. Both males and females can suffer from neurogenic bladder.

What causes neurogenic bladder?

BRADLEY HUNT: There are many causes of a neurogenic bladder. 

Sometimes neurogenic bladder originates at the neuron or nerve level from injury to nerves or neurons that control voiding. These injuries include things like a spinal cord injury, multiple sclerosis, or stroke. Dementia can also affect the brain's ability to tell the bladder to squeeze. Just like someone can have weakness in their arm or leg following a neurological event, someone can also have weakness in their bladder muscle. 

Another common cause is peripheral neuropathy, usually from underlying diabetes or other chronic conditions. Just like numbness can develop in the feet of a diabetic, numbness can also develop in the bladder. Patients with peripheral neuropathy might not sense the need to void because the signal transduction slows down. 

At the muscle level, neurogenic bladder can occur when the muscle fibers lose contact with one another. This muscle-fiber "overlap" is paramount to a muscle's squeezing function. For example, when you flex your bicep, the muscle grows because the fibers go from stretched to stacked as they pull together, causing your arm to move. 

Little by little, the bladder muscle gets stretched. The patient may not sense any change, but at some point, the bladder holds such a large volume that the squeezing unit of the muscle does not overlap enough to contract. Obstruction, whether from a prostate or from stricture, could be the initial cause of a bladder not emptying and lead to the development of a neurogenic bladder.

What happens when someone has neurogenic bladder? What are the symptoms?

BRADLEY HUNT: The symptoms of neurogenic bladder can vary depending on the cause. Often, in the setting of a neurologic event such as a stroke or spinal cord injury, there may not be any sensation in the bladder. The diagnosis is made when urine output decreases and catheterization is required. 

In other cases, there may be frequency, urgency, or incontinence. These symptoms occur because the bladder does not empty well, so it fills up more rapidly and cannot accommodate much volume. 

Nocturnal enuresis, or "wetting the bed" in large quantities at night, can sometimes be a neurogenic bladder symptom. 

How is neurogenic bladder diagnosed?

BRADLEY HUNT: We usually diagnose neurogenic bladder by evaluating emptying studies. Large "post void residual" volumes, or PVRs, are the hallmark of a neurogenic bladder. Tests like bladder scans or cystoscopy can also help the urological team make the diagnosis. 

Urodynamics, which measures the amount of pressure the bladder can generate, is the most definitive test for diagnosing neurogenic bladder. This test is particularly helpful in less black-and-white cases.

In such cases, a hypoactive detrusor (weak bladder) hasn't completely lost all of its squeeze but still cannot generate much pressure. Urodynamics can help determine if the detrusor creates sufficient pressure such that surgical intervention is likely to resolve the issue.

How is neurogenic bladder managed or treated? 

BRADLEY HUNT: Several treatments for neurogenic bladder exist depending on the situation. 

The most pressing issue at the time of initial diagnosis is usually that the bladder empties so poorly that urine backs up into the kidneys, causing renal failure. In this case, short-term management is to decompress the bladder with a catheter. Indeed, catheterization is often the short-term and long-term treatment for neurogenic bladder. 

Various catheter options include clean intermittent catheterization (CIC), Foley catheterization, and suprapubic catheterization. Any of these options can be used, though we hope to use clean intermittent catheterization (CIC) whenever possible. 

If there is some residual detrusor strength, other options may be available. If obstruction is the cause, surgical or medical treatment may sufficiently treat it to avoid catheters. If there is no obstruction, medications like Urecholine can help increase the detrusor pressure. 

A procedure called InterStim can also help optimize detrusor strength. However, this is not right for everyone and would require a complete evaluation before attempting such measures.

Can neurogenic bladder ever be cured?

BRADLEY HUNT: A neurogenic bladder can sometimes be improved to allow for spontaneous voiding, but it usually requires ongoing management. As such, I do not like to use the word "cured" and prefer "controlled." 

In some cases, the underlying cause can be treated (for example, patients with diabetes can work on improving their blood glucose levels), and the bladder muscle may respond in kind. It is unlikely that the bladder would recover to perfect function, but it is certainly possible that it recovers to sufficient function that won't require catheter management.

Are there any potential complications if someone has neurogenic bladder?

BRADLEY HUNT: Neurogenic bladder can cause several complications, the most concerning of which is renal failure. When the bladder is too full, fluid backs up into the kidneys, diminishing kidney function. If caught early, kidney damage is temporary. If it persists for an extended period, it can result in permanent kidney damage and, in the worst cases, lead to dialysis. 

Other complications of neurogenic bladder often include urinary tract infections and bladder calculi. Urinary infections occur far more frequently if the bladder is not draining well. It is the same reason running water is cleaner than still water. Unfortunately, urinary tract infections (UTIs) tend to be a big problem and can be a challenge to control. Bladder stones are easier to manage but do usually require a minor outpatient surgery.

If there's one thing that you want people to understand about neurogenic bladder, what would that be?

BRADLEY HUNT: Neurogenic bladder is a complex diagnosis that often causes distress to patients. My biggest advice is to implement clean intermittent catheterization (CIC) early. Although it's an intimidating step and many people feel they could never do nor tolerate it, most people find that CIC greatly improves their quality of life compared to the other management options.  

CIC also has very little downside when done with good technique. Remember, just because a patient opts for CIC doesn't mean we must stop investigating other routes for managing urine retention.

Are you dealing with bladder dysfunction? Let us help.

Make an appointment with a member of our urology team today.