Several muscles and nerves must work together for the body to control urination.
Neurogenic bladder may be
Flaccid: A flaccid bladder does not contract and the bladder fills up until it overflows. Then urine dribbles out.
Spastic: The person has involuntary bladder contractions and feels the need to urinate even when there is little or no urine in the bladder. Bladder contractions are typically poorly coordinated with the muscle that closes the opening of the bladder (urinary sphincter).
Mixed: Some people have elements of both flaccid and spastic bladder.
Any condition that damages or interferes with nerves that control the bladder or the bladder outlet can cause neurogenic bladder.
The primary symptom is urinary incontinence. People continually release small amounts of urine. Men tend to have erectile dysfunction. Some people with spastic neurogenic bladder also need to urinate frequently, often with an urgent need, and need to get up during the night to urinate. People with spastic neurogenic bladder may have damage to other nerves that causes weakness, muscle spasms, and/or loss of sensation in the legs.
Doctors may suspect neurogenic bladder in people with nerve disorders who have incontinence. Usually, doctors measure the amount of urine remaining in the bladder after the person urinates (postvoid residual volume) by inserting a catheter into the bladder or using ultrasonography. Ultrasonography of the entire urinary tract is also done to detect abnormalities, and some blood tests are done to assess kidney function (see Imaging Tests of the Urinary Tract).
Further tests may be needed depending on the person's condition. More detailed studies of the urinary tract (for example, cystography, cystoscopy, and cystometrography) may be done to check bladder function or to help determine the duration and cause of neurogenic bladder.
Prompt treatment can help prevent permanent dysfunction and kidney damage. Catheterization or techniques to trigger urination can help prevent urine from remaining too long in the bladder. For example, some people with spastic bladder can trigger urination by pressing their lower abdomen or scratching their thighs. When urine remains in the bladder for too long, the person is at risk of urinary tract infections. Inserting a catheter into the bladder periodically is usually safer than leaving a catheter in continuously.
People are encouraged to drink sufficient fluids and to limit calcium in the diet to prevent stones from developing. Doctors also monitor kidney function regularly.
Sometimes drugs given to treat urge incontinence can be helpful (see table Some Drugs Used to Treat Urinary Incontinence). Rarely, people need surgery to create another way for urine to leave the body.