Could the sling position influence the clinical outcome in male patients treated for urinary incontinence? A magnetic resonance imaging study with a 3 tesla system.

Objective: To analyze the morphologic changes visible on magnetic resonance imaging (MRI) after sling procedure in continent patients and to compare MRI findings with the incontinent ones, to detect possible factors explaining the different clinical outcomes.

Methods: Twenty-seven male patients who were treated with Advance sling for urinary stress incontinence after prostate surgery were enrolled: 16 had clinical recovery, whereas 11 had persistent incontinence. Patients after sling were defined as continent if used 0-1 dry "security pad" or incontinent >1 pad. Magnetic Resonance examinations were performed with a 3 Tesla system and included 3-dimensional T2-weighted sequence. Three readers performed a qualitative (representation of the bulb and indentation of the sling) and a quantitative analysis (length of the bulb posterior to the sling and distance of the sling from a line bisecting the pubic symphysis).

Results: The sling was clearly recognizable in all 16 continent patients but only in 2 of 11 incontinent ones. The length of the bulb posterior to the sling was >10 mm (range, 10-28) in all continent patients and in 2 of the incontinent ones. The sling was coincident with a line drawn through the long axis of the pubic bone in 9 of 16 continent patients. A statistically significant association was found between MRI qualitative findings and continence status (P <.0001).

Conclusion: On the basis of our MRI results, the position of the sling and, in particular, the length of the urethral bulb posterior to the sling seem to be correlated with continence and must be considered in case of treatment failure.