Restoration of continence by pessaries: magnetic resonance imaging assessment of mechanism of action.

Abstract

The objective of the study was to determine incontinence pessaries' mechanism of action by measuring changes on urodynamic studies (UDS) and dynamic magnetic resonance imaging (MRI) with and without pessaries in place. Women with stress incontinence had UDS and MRI performed with and without incontinence dish pessaries. Fifteen women were evaluated. Pessary insertion resulted in increased urethral resistance; detrusor pressures increased (33-45 cm H(2)O) and maximal flow rates decreased (30 to 19 mL/second). With Valsalva on MRI, pessaries were associated with decreased posterior urethrovesical angles (175-130 degrees), bladder neck elevation (0.3 below to 0 .8 cm above the pubococcygeal line) and increased urethral lengths (2.4 to 2.97 cm). Bladder neck funneling with cough occurred in 14 patients without pessaries and 3 with pessaries. On UDS and MRI following pessary placement, continence restoration was associated with decreased posterior urethrovesical angles, bladder neck descent and funneling, and increased urethral lengths and resistance to urine flow.