Q-Flap (Morey / Tran / Zinman)
The Q-flap is a circumferential distal penile skin flap with a ventral midline extension — the resulting outline resembles the letter "Q" — designed by Allen Morey, Tran, and Zinman in 2000 for single-stage reconstruction of panurethral strictures.[1] The ventral extension significantly increases usable flap length to a mean of 17 cm (range 15–24 cm), eliminating the need for combined tissue transfer or staged reconstruction in carefully selected uncircumcised patients.
The Q-flap is not the same as the Quartey flap (Quartey 1983). The Quartey flap is the original 1983 transverse preputial / distal-penile island flap. The Q-flap is a Morey 2000 modification that extends the circumferential flap with a ventral midline limb, creating the "Q" outline and adding length specifically for panurethral disease. The terms are sometimes used loosely in practice but represent distinct flap designs with different length capabilities and indications.
For the original 1983 Quartey flap, see Quartey Flap. For the alternative free-graft panurethral strategy, see Preputial Spiral Graft Urethroplasty (PSGU) and Kulkarni One-Sided Dorsolateral BMG. For broader penile-flap principles, see Pedicled Penile / Preputial Flap. For combined-tissue-transfer alternatives, see Combined Dorsal BMG + Ventral Fasciocutaneous Flap (Erickson).
Design — Why the "Q" Shape
The Q-flap starts with a distal circumferential penile skin flap (analogous to the McAninch / Quartey concept), then adds a ventral midline extension along the penile shaft. The resulting outline on the marked penile skin resembles the letter "Q" — circumferential loop with a tail.[1][2]
The added ventral limb provides additional skin length that the circumferential portion alone cannot supply, achieving usable flap lengths sufficient to reconstruct the entire anterior urethra in a single stage.[1]
Indications
- Panurethral anterior urethral strictures — the defining indication, where standard pedicled flaps and single-onlay grafts cannot bridge the entire defect.[1][2]
- Uncircumcised patients with adequate distal penile and preputial skin.[1][2]
- Cases where the surgeon prefers a single-stage flap-based panurethral repair over combined graft / flap (Erickson, Combined Dorsal BMG + Ventral Fasciocutaneous Flap) or staged reconstruction (Bracka two-stage, Johanson two-stage).[3]
The technique requires adequate non-diseased penile / preputial skin and is contraindicated in lichen sclerosus and in circumcised patients with insufficient remaining penile skin.
Technique Highlights
| Step | Detail |
|---|---|
| 1. Marking | Outline a circumferential distal penile skin flap with a ventral midline extension along the shaft — the "Q" shape; total designed length up to 24 cm[1] |
| 2. Flap harvest | Raise as a fasciocutaneous flap on the dartos pedicle with its axial blood supply from the superficial external pudendal vessels (same vascular basis as the Quartey flap)[1][4] |
| 3. Urethrotomy | Open the panurethral stricture along its full length |
| 4. Flap inset | Configure as an onlay to augment the urethral plate; the ventral limb of the "Q" reaches the proximal extent of the stricture, the circumferential portion covers the more distal segments |
| 5. Closure | Standard layered closure with a urethral catheter |
Outcomes
The Morey 2000 original description reports successful single-stage reconstruction of panurethral strictures with mean flap length 17 cm (15–24 cm), eliminating the need for supplemental grafts in those cases.[1] The technique is referenced in the broader penile-skin-flap literature as the gold-standard pedicled-flap option for panurethral disease in uncircumcised patients when single-stage flap-only reconstruction is desired.[2]
Detailed long-term comparative cohort data specific to the Q-flap remain limited; in the contemporary GURS landscape, ~ 90% of reconstructive surgeons now prefer multiple BMGs over combined graft / flap for panurethral strictures,[5] and the Preputial Spiral Graft Urethroplasty (PSGU) is emerging as a free-graft alternative using the same donor tissue.
Comparison Table — Quartey vs Q-Flap
| Feature | Quartey Flap (1983) | Q-Flap (2000) |
|---|---|---|
| Originator | J.K.M. Quartey | Morey, Tran, Zinman |
| Flap design | Transverse preputial / penile island | Circumferential flap + ventral midline extension ("Q" shape) |
| Typical length | 12–15 cm | Mean 17 cm (15–24 cm) |
| Primary indication | Anterior urethral strictures (segmental, long) | Panurethral strictures |
| Need for supplemental grafts | May be required for very long strictures | Eliminated by extended flap length |
| Vascular pedicle | Dartos / superficial external pudendal vessels | Same (dartos / SEPA) |
| Prerequisite | Uncircumcised (preputial skin) | Uncircumcised; adequate ventral shaft skin for the extension |
Limitations
- Requires uncircumcised patients with adequate preputial and ventral shaft skin.
- Contraindicated in lichen sclerosus — penile skin is unreliable; oral mucosa preferred.
- Limited published long-term data compared with the McAninch circular flap and BMG urethroplasty.
- Increasingly supplanted at high-volume centers by dual-BMG approaches and the spiral preputial graft (PSGU) — but remains a valuable single-stage flap option when the surgeon's experience and patient anatomy favor a pedicled-flap reconstruction.
References
1. Morey AF, Tran LK, Zinman LM. Q-flap reconstruction of panurethral strictures. BJU Int. 2000;86(9):1039-1042. doi:10.1046/j.1464-410x.2000.00974.x.
2. Joshi PM, Bandini M, Kulkarni SB. Common flaps in genitourinary reconstruction. Urol Clin North Am. 2022;49(3):361-369. doi:10.1016/j.ucl.2022.04.001.
3. Wessells H, Morey A, Souter L, Rahimi L, Vanni A. Urethral stricture disease guideline amendment (2023). J Urol. 2023;210(1):64-71. doi:10.1097/JU.0000000000003482.
4. Quartey JK. One-stage penile/preputial cutaneous island flap urethroplasty for urethral stricture: a preliminary report. J Urol. 1983;129(2):284-287. doi:10.1016/s0022-5347(17)52051-0.
5. Berg C, Singh A, Hu P, et al. Current trends in the use of buccal grafts during urethroplasty among Society of Genitourinary Reconstructive Surgeons. Urology. 2024;191:139-143. doi:10.1016/j.urology.2024.06.019.