Wise B G, Cardozo L D, Cutner A, Benness C J, Burton G
Department of Obstetrics and Gynaecology, King's College Hospital, London.
Br J Urol. 1993 Jul;72(1):26-9. doi: 10.1111/j.1464-410x.1993.tb06451.x.
The phenomenon of urethral instability has been poorly defined and its significance is disputed. The aim of this study was to investigate the prevalence and significance of urethral instability in a group of women with idiopathic detrusor instability. Urethral instability was defined as a spontaneous fall in maximum urethral pressure of one-third or more, in the absence of detrusor activity, over a 2-min period. Urethral instability occurred in 42% of patients with detrusor instability and was strongly associated with the sequence of relaxation of the urethra prior to unprovoked detrusor contraction. Women with detrusor instability and a stable urethra exhibited primary contraction of the detrusor. The symptom of stress incontinence was more common in women with urethral instability. Women with detrusor instability may be subdivided into 2 groups on the basis of urethral instability, the presence of which suggests a primary dysfunction of the urethra. Such patients may derive more benefit from treatment with an alpha adrenoceptor agonist in addition to (or instead of) standard anticholinergic therapy.
