To compare the ultrasonographic positional changes of mid-urethral sling(MUS) tape in relation to symphysis pubis, and the different clinical outcomes among women who underwent MUS insertion with MiniArcTM or MonarcTM for the treatment of stress urinary incontinence 3 years after.
Materials and methods
A retrospective follow-up study on patients with clinically confirmed stress urodynamic incontinence and urodynamic stress incontinence who had undergone MiniArc or Monarc surgery. Data regarding preoperative evaluation, intraoperative complications and post-operative follow-ups were collated. Main outcome is to determine the change in position of the sling through measurement of the x- and y-axis at rest and during Valsalva maneuver using the 3D introital ultrasound.
A total of 138 patients were evaluated, 82 belonged to Monarc and 56 to MiniArc. At 3years, objective and subjective cure rates for MiniArc and Monarc were comparable (88%, 91%; p>0.05; 83%, 89%, p>0.05 respectively). Ultrasonographic changes between MiniArc and Monarc from 6 months to 3 years, showed MiniArc to exhibit significant movement in both x- [3.0 ±0.4 mm vs. 2.2 ±0.3 mm (p = 0.02) at rest; 2.6 ±0.3 mm vs. 1.6 ±0.3 mm (p<0.001) during valsalva] and y-axis [3.5 ±0.5 mm vs. 2.0 ±0.3 mm (p<0.001) at rest; 3.3 ±0.5 mm vs. 2.9 ±0.3 mm (p = 0.037) during Valsalva]. The mobility of MiniArc was significantly more than Monarc from rest to Valsalva (1.1 ±0.4 mm vs. 0.3 ±0.3 mm, p = 0.001). Tightness of the sling assessed from the major and minor axis of the urethral core had no significant difference in both groups at rest and during Valsalva. Urethral kinking percentage and the location of the sling did not yield statistical difference.
Maintenance of continence rates of mid-urethral slings depends on the compressive effect of the sling on the urethra, urethral kinking, and sling fixation. From 6months to 3 years, MiniArc changed its position in both x- and y-axis over time, which the authors attribute to loosening of the anchoring mechanism since no clinical relevance could be sought.