Can ultrasound replace ambulatory urodynamics when investigating women with irritative urinary symptoms?
OBJECTIVE
To determine whether transvaginal ultrasound measurement of bladder wall thickness could replace ambulatory urodynamics when investigating women with lower urinary tract dysfunction not explained by conventional laboratory urodynamic studies.


METHODS
A blinded prospective study.


METHODS
Tertiary referral unit in a London teaching hospital.


METHODS
One hundred and twenty-eight women referred for ambulatory urodynamics with equivocal laboratory urodynamic findings or whose symptoms were not explained by the laboratory urodynamic findings.


METHODS
Transvaginal ultrasound assessment of bladder wall thickness was performed in three planes with an empty bladder prior to ambulatory urodynamics. Mean bladder wall thickness was calculated and the results analysed with respect to the ambulatory urodynamic diagnosis.


METHODS
Mean bladder wall thickness in women with a normal ambulatory study or a diagnosis of detrusor instability, genuine stress incontinence (GSI) or mixed incontinence.


RESULTS
Using a one way analysis of variance (ANOVA) bladder wall thickness was found to be significantly different in all diagnostic groups and this reached significance (P = 0.0001). There was no overlap in the 95% confidence intervals representing a diagnosis of detrusor instability or genuine stress incontinence.


CONCLUSIONS
Transvaginal ultrasound assessment of mean bladder wall thickness is a sensitive screening tool, which can detect detrusor instability in those women with equivocal laboratory urodynamics. In women who have no evidence of GSI on laboratory studies, a cutoff of 6.0mm is highly suggestive of detrusor instability. However, in those women with GSI then ambulatory studies probably remain the investigation of choice.
Robinson
Dudley
D
Department of Urogynaecology, King's College Hospital, London, UK.
Anders
Kate
K
Cardozo
Linda
L
Bidmead
John
J
Toozs-Hobson
Philip
P
Khullar
Vikram
V
D000553:Ambulatory Care; D000704:Analysis of Variance; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D011446:Prospective Studies; D014463:Ultrasonography; D001745:Urinary Bladder Diseases / Q000000981:diagnostic imaging* / Q000473:pathology / Q000503:physiopathology; D014550:Urinary Incontinence, Stress / Q000000981:diagnostic imaging / Q000503:physiopathology; D016055:Urinary Retention / Q000000981:diagnostic imaging* / Q000503:physiopathology; D014563:Urodynamics