Neurogenic lower urinary tract dysfunction.

The two roles of the lower urinary tract are storage of urine and emptying at appropriate times. Optimal and coordinated activity of the bladder and urethra is subject to complex neural control which involves all levels of the nervous system, from cortex to peripheral nerve. This explains the high prevalence of urinary disturbances in neurological disease. Information obtained from history taking and supplemented by use of a bladder diary forms the cornerstone of evaluation. Ultrasonography is used to assess the degree of incomplete bladder emptying, and for assessing the upper tracts. Urodynamic tests, with or without simultaneous fluoroscopic monitoring, assess detrusor and bladder outlet function and give fundamental information about detrusor pressure and thus the risk of upper tract damage. Impaired emptying is most often managed by clean-intermittent self-catheterization, which should be initiated if the postvoid residual urine exceeds one-third of bladder capacity or is greater than 100mL, or rarely if spontaneous voiding is dangerous due to high detrusor pressure. Storage symptoms are most often managed using antimuscarinic medications. Intradetrusor injection of botulinum toxin type A is emerging as an effective treatment for managing detrusor overactivity. Understanding of the underlying mechanism of lower urinary tract dysfunction is crucial for effective management.