Describing Bladder Storage Function: Overactive Bladder Syndrome and Detrusor Overactivity

After a comprehensive review of terminology of lower urinary tract function/dysfunction, the International Continence Society (ICS) has recommended the use of the terms overactive bladder syndrome (OAB) and detrusor overactivity. Detrusor overactivity is defined as a urodynamic observation characterized by involuntary detrusor contractions during the filling phase that may be spontaneous or provoked. Detrusor overactivity is subdivided into idiopathic detrusor overactivity and neurogenic detrusor overactivity. Because detrusor overactivity is a urodynamic diagnosis, it is essential to record symptoms and signs during urodynamic studies to correlate them with any involuntary contractions. The ICS 2002 report describes 2 types of detrusor overactivity: (1) phasic, which may or may not lead to urinary incontinence; and (2) terminal, which is a single involuntary detrusor contraction that often results in complete bladder emptying. OAB, as defined by ICS 2002, is a new term and is a symptomatic diagnosis. OAB is defined as urgency, with or without urge incontinence, and usually with frequency and nocturia. The ICS endorsement of the term OAB recognizes that patients with this symptom syndrome are almost always treated by nonsurgical means on an empirical basis, ie, without a urodynamic confirmation of the presumed diagnosis, detrusor overactivity. The ICS believes that these terms are more intuitive and will make it easier for patients and physicians alike to understand. It is hoped that general use of the new ICS definitions will facilitate effective communications between patients and their physicians concerning their urologic dysfunctions.