Skip to main content

Midurethral Sling Trocars (TVT / TOT)

Curved-needle trocars used to pass the mesh tape of a midurethral sling through the retropubic space (TVT) or the obturator foramen (TOT). The trocar is the defining instrument of the midurethral-sling family — the same polypropylene tape can take any of three routes (retropubic, transobturator, single-incision) depending on which trocar is used and in which direction it is passed. Originally called a "tunneller" in the Petros / Ulmsten IVS literature; the modern WARWIKI convention is trocar, matching the parallel terminology in the Raz-Pereyra, Stamey, and suprapubic catheter trocar systems.[1][2]

For the procedure-level page (indications, outcomes, AUA/SUFU positioning), see the Female SUI database.

Trocar Family​

TrocarApproachTrajectoryDirectionStandard angle
TVT trocar (Gynecare/Ethicon)RetropubicVertical through space of RetziusBottom-to-top (vaginal → suprapubic) or top-to-bottom~ 120° (re-engineered from the 90° IVS); 3.0 mm shaft in TVT-Exact
IVS tunneller (Petros / Ulmsten, 1990s)RetropubicVerticalBottom-to-top90° with delta-wing handle and blunt wedge tip
TOT trocar (Delorme, outside-in)TransobturatorHorizontal through obturator membraneSkin → vaginaHelical / curved
TVT-O trocar (de Leval, inside-out)TransobturatorHorizontalVagina → skinHelical / curved
Single-incision mini-sling inserterSingle-incisionShort anchor / barb deploymentVagina-onlyShort helical or fixed-arm
Stamey needle (improvised TOT trocar)TransobturatorAs substitute for commercial helical trocar in self-prepared meshEither directionCurved-tip ligature carrier[3]

Design Notes​

Retropubic (TVT) trocar​

  • Two solid stainless-steel needles with sharp tips, joined by the polypropylene Amid type-1 mesh tape; each end carries a heavy screw-on handle for the throw.[1]
  • IVS → TVT angle change (90° → ~ 120°) lost the precise vertical-plane tactile feedback of the original Petros design; this design change has been cited as a contributor to bladder-perforation risk.[1]
  • TVT-Exact modification: rigid 3.0 mm shaft intended to lower complications; bleeding events still reported with this device (Masata 2015).[4]
  • The retropubic throw is blind through the space of Retzius — intraoperative cystoscopy is mandatory to confirm no bladder perforation.[5]

Transobturator (TOT) trocars​

  • Curved / helical to traverse the obturator membrane horizontally.
  • Outside-in (Delorme) — enters at the genitofemoral fold, exits the vaginal dissection. Cadaveric data place the tape farther from the obturator canal (2.3 cm) but closer to the ischiopubic ramus (0.04 cm).[6]
  • Inside-out (de Leval / TVT-O) — exits the skin from the vaginal entry. Tape sits closer to the obturator canal (1.3 cm) but farther from the ischiopubic ramus (0.39 cm); meta-analysis shows fewer vaginal-sulcus perforations (OR 0.14) with a trend toward more groin / thigh pain.[6][7]

Reconstructive-Urology and Urogyn Uses​

The trocar is the procedure-defining instrument for:

  • Retropubic TVT — gold-standard MUS for primary female SUI in the typical patient.
  • TOT / TVT-O — alternative for the patient with prior pelvic surgery, dense Retzius scarring, or higher bladder-perforation risk, accepting the trade-off of more groin-thigh pain.
  • High-risk SUI (ISD, obesity, recurrent SUI, concomitant POP) — Kim 2019 meta-analysis favors the retropubic trocar over the transobturator on both objective and subjective cure.[8]
  • Self-prepared (non-kit) mesh slings in resource-limited settings — a Stamey needle substitutes for the commercial helical trocar in published comparative series.[3]

Tape-to-Urethra Distance — Tensioning Technique​

The trocar pass is only half the operation; the tension-free position is set by a calibrated suburethral spacer. Two standardized approaches:

  • Ulmsten original — 16 Fr Foley intraurethral + Metzenbaum scissor blade (3–5 mm) between tape and urethra.[9]
  • TOT 8/4 (Ludwig 2016) — Hegar 8 intraurethral + Hegar 4 suburethral to set a consistent 3–5 mm gap; standardization rose from 28% → 83% of cases.[9]

Complication Profile by Trocar​

ComplicationRetropubic trocar (TVT)Transobturator trocar (TOT / TVT-O)
Bladder perforationHigher (~ 5 more per 1,000); mandatory cystoscopyLower — trajectory avoids Retzius
Vascular / bowel injuryRare (vascular 0.07%, bowel 0.04%)Very rare
Postoperative voiding dysfunctionHigherLower
Groin / thigh painLowerHigher (~ 83 more per 1,000 at 6 mo)
Vaginal-sulcus perforationN/AHigher with outside-in vs inside-out (OR 0.14 for inside-out)[7]

Outcomes Summary​

  • TOMUS trial (Richter 2010) — TVT and TOT objectively equivalent at 12 months.[10]
  • Long-term cure ~ 80–90% at 5 yr for both routes, with some long-term signals favoring the retropubic trocar in high-risk subgroups.[8][11]
  • Operative time and hospital stay slightly shorter with TOT.[12]
  • AUA/SUFU 2023 — MUS remains the dominant surgical option for female SUI; choice of trocar route is individualized; some long-term data favor retropubic.[13]

Limitations​

  • Blind retropubic throw — even with the modern 3.0 mm shaft, the trajectory is not visualized; mandatory cystoscopy is the safety net.
  • Vascular and obturator-canal proximity — the few centimeters between safe and unsafe trocar trajectories are anatomically tight, particularly in the obese pelvis and the patient with prior retropubic surgery.
  • Regulatory and medicolegal scrutiny of transvaginal mesh has led to restriction of MUS devices in some countries; the MUS itself remains the recommended SUI surgical option by AUA/SUFU and EAU, but the regulatory environment varies.[5][13]

References​

1. Petros P, Abendstein B. "The mechanics of urethral closure, incontinence, and midurethral sling repair. Part 3 surgical applications (1990–2016)." Neurourol Urodyn. 2019;38(2):818–24. doi:10.1002/nau.23840

2. Ford AA, Taylor V, Ogah J, et al. "Midurethral slings for treatment of stress urinary incontinence review." Neurourol Urodyn. 2019;38 Suppl 4:S70–5. doi:10.1002/nau.24030

3. Zyczkowski M, Nowakowski K, Kuczmik W, et al. "Tension-free vaginal tape, transobturator tape, and own modification of transobturator tape in the treatment of female stress urinary incontinence: comparative analysis." Biomed Res Int. 2014;2014:347856. doi:10.1155/2014/347856

4. Masata J, Svabik K, Martan A. "Bleeding complication with the TVT-Exact procedure: a report of two cases." Int Urogynecol J. 2015;26(2):303–5. doi:10.1007/s00192-014-2494-7

5. Abdel-Fattah M, Cooper D, Davidson T, et al. "Single-incision mini-slings for stress urinary incontinence in women." N Engl J Med. 2022;386(13):1230–43. doi:10.1056/NEJMoa2111815

6. Zahn CM, Siddique S, Hernandez S, Lockrow EG. "Anatomic comparison of two transobturator tape procedures." Obstet Gynecol. 2007;109(3):701–6. doi:10.1097/01.AOG.0000255662.79008.18

7. Madhuvrata P, Riad M, Ammembal MK, Agur W, Abdel-Fattah M. "Systematic review and meta-analysis of 'inside-out' versus 'outside-in' transobturator tapes in management of stress urinary incontinence in women." Eur J Obstet Gynecol Reprod Biol. 2012;162(1):1–10. doi:10.1016/j.ejogrb.2012.01.004

8. Kim A, Kim MS, Park YJ, et al. "Retropubic versus transobturator mid urethral slings in patients at high risk for recurrent stress incontinence: a systematic review and meta-analysis." J Urol. 2019;202(1):132–42. doi:10.1097/JU.0000000000000222

9. Ludwig S, Stumm M, Mallmann P, Jager W. "TOT 8/4: a way to standardize the surgical procedure of a transobturator tape." Biomed Res Int. 2016;2016:4941304. doi:10.1155/2016/4941304

10. Richter HE, Albo ME, Zyczynski HM, et al. "Retropubic versus transobturator midurethral slings for stress incontinence." N Engl J Med. 2010;362(22):2066–76. doi:10.1056/NEJMoa0912658

11. Laurikainen E, Valpas A, Aukee P, et al. "Five-year results of a randomized trial comparing retropubic and transobturator midurethral slings for stress incontinence." Eur Urol. 2014;65(6):1109–14. doi:10.1016/j.eururo.2014.01.031

12. Huang ZM, Xiao H, Ji ZG, Yan WG, Zhang YS. "TVT versus TOT in the treatment of female stress urinary incontinence: a systematic review and meta-analysis." Ther Clin Risk Manag. 2018;14:2293–303. doi:10.2147/TCRM.S169014

13. Kobashi KC, Vasavada S, Bloschichak A, et al. "Updates to surgical treatment of female stress urinary incontinence (SUI): AUA/SUFU guideline (2023)." J Urol. 2023;209(6):1091–8. doi:10.1097/JU.0000000000003435