Durability of Macroplastique volume and configuration in women with stress urinary incontinence secondary to intrinsic sphincter deficiency: A retrospective review

Objectives: To evaluate the durability of Macroplastique® (MPQ) volume and configuration in women with stress urinary incontinence (SUI) secondary to intrinsic sphincter deficiency (ISD) using serial three-dimensional ultrasound (3DUS) measurements. Methods: Following Institutional Review Board approval, charts of women with SUI and ISD (defined based on leak point pressure; lateral imaging of urethral support without hypermobility) who underwent MPQ were reviewed from a prospectively maintained database. All had at least two serial transperineal 3DUS measurements with no MPQ or other bulking agent injection between measurements. 3DUS was performed using the Philips IU22 ultrasound system with endovaginal 3D 9-3V end-fire probe typically at 6‑8 weeks post-injection and yearly thereafter. The same imaging team blinded to clinical outcomes evaluated volume and configuration (circumferential/symmetric or asymmetric) at each 3DUS. Results: Between 2011 and 2019, 62 of 174 women met study criteria. Those with prior other bulking agent injection or having ≤1 3DUS follow-up were excluded. Seventy-one percent of patients had one injection, while the remainder had two or more (29%). Median time between first and second 3DUS was 12 months. The mean change in MPQ volume between the first and last 3DUS measurement was −0.2 cc (95% CI: −0.5 to 0.004; P =.054). A median of 5.0 cc were injected in each patient. Forty-seven women had symmetric MPQ at first 3DUS, of whom only five (11%) had a follow-up 3DUS showing asymmetric MPQ distribution. Conclusions: At mid-term follow-up, repeat transperineal 3DUS after MPQ injection revealed minimal change in volume and configuration in the urethral wall.