title: Bladder base insufficiency.
abstract: The normal female bladder base is defined. It is shown that the trigone does not always form part of a flat base. In 25% of all female patients referred for cystourethrography a specific defect of the anterior part of the base is seen caused by an insufficient upwards and backwards suspension of the bladder neck. 92% of these patients are stress incontinent. Urodynamically they have low protracted flows, but the most characteristic feature is a very low intravesical pressure and particularly a very low opening pressure. The low pressure is due to the fact that the internal orifice does not close correctly because of insufficient support. The protracted and low flows are due to an increased tone in the posterior urethra needed for continence when the bladder neck has lost its passive continence function.
mesh_terms: D005260:Female; D006801:Humans; D001743:Urinary Bladder / Q000033:anatomy & histology / Q000503:physiopathology; D014550:Urinary Incontinence, Stress / Q000000981:diagnostic imaging / Q000209:etiology*; D014554:Urination; D014567:Urography