Neurogenic Bladder

What is a neurogenic bladder?

In a neurogenic bladder, the nerves and muscles in the urinary system that carry signals between the bladder, spinal cord and brain do not function properly. This leads to poor bladder control, where it may not fill or empty the right way leading to lower urinary tract symptoms (LUTS).

The patterns of LUTS are related to the level of the neurological disorder, which may lead to dysfunction of the bladder and/or urinary sphincter, resulting in storage symptoms (urgency, frequency, urge urinary incontinence) or voiding symptoms (poor urinary flow, straining, hesitancy or terminal dribbling). The levels are classified into:

Suprapontine (brain) — this results in an overactive bladder with normoactive urinary sphincter. The patient presents with mainly storage symptoms with no retention of urine.
Infrapontine to suprasacral (upper spinal) — this results in an overactive bladder and sphincter. The patient presents with both voiding and storage symptoms, often with significant retention of urine.
Infrasacral (lower spinal) — this results in an underactive bladder with either normoactive or underactive sphincter. The patient presents with mainly voiding symptoms with significant retention of urine.

What is neuro-urology?

Neuro-urology focuses on diseases and functional disorders of the urinary tract system and genitalia that are related to neurological disorders and spinal cord injuries. The control of the lower urinary tract requires an intact complex nervous network, which can be impaired by neurological disorders. As a result, patients might experience distressful symptoms such as urgency to urinate, incontinence, and frequent urination. For example, neuro-urology targets patients with neurological conditions such as Parkinson’s disease or multiple sclerosis or spinal cord injury who may encounter urological problems like an overactive bladder or underactive bladder.

What causes a neurogenic bladder?

A neurogenic bladder is generally damage caused by illness or injury that controls the bladder. These may include:

Parkinson’s disease (PD)
Multiple sclerosis
Diabetes
Diseases that affect the nervous system
Spinal cord injuries
Stroke
Heavy metal poisoning
Brain or spinal cord injuries
Congenital nerve problems
Cancers in the pelvis eg cervical or rectal cancer

What are the symptoms of neurogenic bladder?

Symptoms of a neurogenic bladder may differ from person to person. However, common notable symptoms are:

Bladder stones
Urinary incontinence
Urinary frequency
Dribbling urine
Inability to feel when the bladder is full
Urinary tract infections (UTI)
Urinary urgency
Inability to empty the bladder completely
Kidney impairment / failure in severe cases

What happens if we leave a neurogenic bladder untreated?

If left untreated, neurogenic bladder symptoms may lead to bladder stones, kidney damage, worsening bladder function and recurrent UTIs.

How is neurogenic bladder diagnosed?

Diagnosis for a neurogenic bladder often involves checking brain, spinal cord and bladder function. Your urologist will obtain a detailed medical history and order various tests such as:

Urine and blood tests

Urinalysis and urine culture — urine samples will be taken and sent for laboratory testing to check for blood or infection.
Blood tests — samples of your blood will be taken and sent for laboratory testing to check kidney function.
Frequency Voiding Bladder Diary — this is a detailed self-record of urinary habits, including the number of times one urinates in the day and night, the time intervals between them, the volume of urine voided each time, any sensation of urgency or urine leak and the timing and amount of water/fluid intake.

Urine Flow Studies

Uroflowmetry and post-void residual urine — A screening test to assess how well the lower urinary tract functions. It measures the flow and speed of urination, the volume of urine voided and the amount of urine left in the bladder after voiding. Uroflowmetry may be recommended by the doctor if you experience symptoms, such as difficulty in urinating, slow urination, or weak urine stream. Uroflowmetry also helps to screen for other urinary issues such as a weakened bladder, enlarged bladder, or neurogenic bladder dysfunction.

Urodynamic Study — A combination of 2 components, cystometry and pressure-flow studies. A video component may be added, especially for the evaluation of neurogenic bladder.
- Cystometry — A test that measures bladder functions and helps to identify problems related to the filling and sensation of the bladder. The test measures how much urine your bladder can hold, bladder pressure, and how full your bladder is when you have the urge to empty your bladder. Cystometry may be recommended by the doctor if you have difficulty controlling or emptying your bladder or have urinary incontinence.
- Pressure flow studies — Pressure flow studies measure the pressures inside the bladder and abdomen simultaneously to give information on the pressure the bladder needs to urinate and how fast the urine flows at that pressure. The test provides information on urinary incontinence and bladder outflow obstruction.
- Video — with the aid of contrast and x-rays, this study can provide real-time information of how the bladder and external sphincter relate to one another during urination.

Imaging tests

Ultrasound of the kidneys, bladder and prostate and/or CT urogram — these imaging studies aim to evaluate the upper and lower urinary tracts to look for other differential diagnoses and to assess any possible complications.

How is a neurogenic bladder treated?

The primary aims of treatment are to :

Protect the upper urinary tract
Achievement or maintenance of urinary continence
Improvement of lower urinary tract functions
Improvement in quality of life

Due to the varied nature of neurogenic bladder, treatment options are highly individualised and may include the following.

Conservative and Medical Treatments

Behavioural therapy, pelvic floor exercises and bladder training — aims to improve urinary incontinence and bladder storage.
Assisted bladder emptying — this includes special voiding techniques as advised by your urologist or intermittent or long-term insertion of urinary catheters to empty the bladder.
Bladder Rehabilitation, including electrical stimulation — consists of various methods, including electrical or magnetic stimulation, to re-establish bladder functions in patients with neurogenic bladder.
Medications — These include drugs for storage symptoms (anti-muscarinics or beta 3 adrenergic receptor agonists) and for voiding symptoms (α-blockers).
Neurotoxin injections — Botulinum toxin A can be injected into the bladder muscles to reduce spasms and bladder overactivity.

Surgical treatments

Suprapubic cystostomy

Patients with neurogenic bladder may require a long-term indwelling urethral catheter to empty their bladders. Long term indwelling urethral catheters can lead to issues such as recurrent urinary tract infections and injury to the urethra or penis. Cystostomy is a surgical procedure where a tube, also known as suprapubic catheter, is inserted into the bladder via the lower abdomen to drain urine. Suprapubic cystostomy is considered to be a less invasive form of urinary diversion.

The placement of the suprapubic catheter can be performed through an open or percutaneous approach.

Percutaneous cystostomy: During this procedure, the surgeon inserts the catheter directly through the lower abdominal wall using ultrasound and/or cystoscopic (direct visualisation of the inner part of the bladder with a scope) guidance
Open cystostomy: In this approach, the surgeon makes a small incision above the pubic area to gain access to the bladder. The catheter is then inserted directly into the bladder, allowing urine to be drained without having a tube going through the genital area. Open cystostomy is usually performed if the patient had undergone any previous lower abdominal surgeries.

The catheter usually stays inserted for 4 to 8 weeks before it needs to be changed or removed.

External Sphincterotomy

The function of the bladder is to store and empty urine. This requires coordination between the detrusor muscle, urinary sphincter, and central nervous system. However, in patients with spinal cord injuries and other neurological disorders, the bladder muscles and urinary sphincter can lose coordination, resulting in bladder outlet obstruction.

External sphincterotomy helps to overcome that by impairing the external sphincter function in order to reduce the bladder outlet resistance and the bladder pressures during urination. The external sphincter is resected using electrocautery or a cold knife.

There may be resultant urinary incontinence after external sphincterotomy, and may be managed by external devices.

Artificial Urinary Sphincter (AUS)

Implantation of AUS is performed for patients with neurogenic stress urinary incontinence. It consists of a fluid-filled cuff that squeezes the urethra, a balloon reservoir implanted in the abdomen and a pump implanted at the scrotum.

During urination, the pump is activated by the patient, and the fluid-filled cuff is deflated as the fluid is transferred into the balloon reservoir, allowing the patient to pass urine. Once urination is completed, the fluid flows from the reservoir into the cuff once again, preventing urinary incontinence. The success rate of AUS is high, but some patients may require reintervention due to mechanical failure.

Bladder Augmentation

The main aims of bladder augmentation are to increase bladder capacity and reduce bladder muscle overactivity and pressure to protect the upper urinary tract. In this procedure, the bladder capacity is expanded by incorporating a segment of the intestines into the bladder. It is generally performed only after more conservative options have failed. Intermittent catheterisation may be necessary after this surgery.

Urinary Diversion

Urinary diversion is a surgical procedure to provide an alternative pathway for urine to pass out of the body due to neurogenic bladder dysfunction. Urinary diversion can be divided into continent diversion and incontinent diversion. An ileal conduit is the most common form of incontinent urinary diversion. During the ileal conduit diversion procedure, a small part of the small intestine, the terminal ileum, will be used to divert urine from the ureters to an external collecting bag. One end of the terminal ileum is attached to the ureters, while the other end is attached to a stoma (a small opening in the abdomen). A urostomy bag is placed over the stoma to hold the urine. The bag comes with a valve for drainage of the urine.

Summary

A neurogenic bladder may be the result of damage to the neurological system. This leads to an inability to control our bladder and can, understandably, greatly affect our quality of life. Thankfully, there are a variety of interventions that help manage these symptoms. Treatment is also aimed at preventing eventual kidney damage.

If you experience any of the aforementioned symptoms, please visit your urologist for a proper diagnosis and personalised treatment plan tailored to your needs and concerns.

Neurogenic Bladder