Fig. 2.

a Typical signals from a continent subject. p _ura and p _ves are measured using the urethral sleeve sensor. p _clo is the subtracted value of p _ves from p _ura. All pressures are expressed in centimeters of water on the y-axis. Time is on the x-axis. During Valsalva, the continent subject increases her abdominal pressure and vesical pressure (p _ves), and there is a corresponding increase in urethral pressure (p _ura). The subject is able to maintain p _clo > 0, and no leakage is observed. During PFMC, the continent patient is able to increase her p _clo pressures by increasing her p _ura. This subject is clearly performing the PFMC correctly because there is no increase in p _ves. p _ura urethral pressure, p _ves vesical pressure, p _clo urethral closure pressure, PFMC pelvic floor muscle contraction. b Typical signals from an incontinent subject. During Valsalva, the incontinent subject is unable to maintain her urethral closure pressures when vesical pressure increases and p _clo becomes <0 cm H₂O, resulting in urine leakage. Even in the incontinent subject there is a modest increase in p _clo during a properly performed PFMC