A comparison of urethral pressure profilometry using microtip and double-lumen perfusion catheters in women with genuine stress incontinence

Abstract

Objective: To compare urethral pressure profilometry measurements using microtip transducer and double-lumen perfusion catheters.

Design: Prospective study.

Setting: Tertiary referral urogynaecology unit.

Sample: Three hundred and ninety two non-pregnant women with various lower urinary tract symptoms.

Methods: Multichannel urodynamic investigations were performed using double-lumen perfusion catheters with external pressure transducers in 392 women. For those 301 (76.8%) diagnosed as having genuine stress incontinence, an investigation with microtip transducers followed. For data analysis, a mixed-effects model was used to evaluate changes in the urethral profilometry and an approach proposed by Bland and Altman was applied to access agreement between the two techniques.

Results: Of the 301 women with genuine stress incontinence, 272 were eligible for this study. In resting status, the differences between the two techniques were statistically significant (48.9cm H2O vs 73.4cm H2O, P = 0.0001) after adjusting for age. Moreover, the agreement study also confirmed that these two techniques do not agree sufficiently.

Conclusion: Maximum urethral closure pressure obtained from the double-lumen catheter was significantly higher than that obtained from the microtip catheter. Use of the double-lumen catheter for the measurement of maximum urethral closure pressure can be considered a reliable technique since its reproducibility is as good as that of the microtip catheter. Therefore, the diagnosis of 'low pressure urethra' will be different between the two techniques.