Voiding dysfunction: definitions

'Lower urinary tract symptoms' is a term that describes symptoms related to both the storage and emptying phases of the micturition cycle. Storage symptoms include urinary frequency urgency, urge incontinence, nocturia, dysuria and other kinds of pain emanating from the bladder or urethra. Emptying symptoms consist of hesitancy, straining to void, difficulty starting, diminished stream, a feeling of incomplete bladder emptying and urinary retention. In both sexes, the etiology of lower urinary tract symptoms is multifactorial, and symptoms are a poor indicator of underlying pathophysiology. In men, lower urinary tract symptoms are most often attributed to prostatic obstruction, but only approximately two-thirds of men with lower urinary tract symptoms meet the accepted diagnostic criteria for obstruction. Approximately half have detrusor overactivity and a smaller number have impaired detrusor contractility, sensory urgency, sphincteric incontinence, polyuria or nocturnal polyuria. In women, lower urinary tract symptoms are often considered to result from hormonal abnormalities, childbirth, aging, or previous surgery, but the multifactorial underlying pathophysiology is similar to that seen in men, except for a much lower incidence of urethral obstruction and a high incidence of sphincteric incontinence. Treatment typically begins with empiric, conservative therapies aimed at resolving detrusor instability or bladder outlet obstruction. However, although either or both of these etiologies may exist in the individual with lower urinary tract symptoms, treatment may fail as a result of another cause. We believe that treatment based on the pathophysiology of the symptoms will lead to better outcomes than treatment based on symptoms alone.