Modified Bipedicle Scrotal Tunnel Flap (Murányi Technique)
The Murányi modified bipedicle scrotal tunnel flap is a single-stage penile skin reconstruction developed for paraffin-induced sclerosing lipogranuloma. Its defining innovation is a subcutaneous scrotal tunnel through which the denuded shaft is pulled, combined with an inverted-V ventral closure that converts the historical T-junction (a known necrosis site) into a longitudinal scar. In the largest single-institution series (n = 49), it achieved 90% patient-reported surgical success and 100% preservation of intercourse ability, with an overall complication rate of 26.5%.[1]
For the related single-stage flap relying on a central window rather than a tunnel, see Bipedicled Anterior Scrotal Flap (Fakin). For the graft alternative, see Penile Skin Grafting. For the full decision framework, see Penile Reconstruction.
Rationale
Penile paraffinoma / sclerosing lipogranuloma requires complete excision of all infiltrated skin and subcutaneous tissue, often leaving a circumferential shaft defect.[1][2][3] The Murányi modification was designed to address limitations of prior techniques:[1]
| Prior approach | Limitation |
|---|---|
| Jeong 1996 bilateral scrotal flaps | Complex flap design; T-style ventral-coronal anastomosis prone to necrosis[3][4] |
| Pribaz two-stage scrotal flap | Second operation, prolonged recovery[5] |
| STSG / FTSG | Suboptimal when residual foreign material on the corpora prevents graft take[3] |
| Fakin bipedicled anterior scrotal flap | Requires central window in the elevated flap + circumferential wrap[6] |
Tunneling simplifies the dissection — the scrotal skin naturally envelops the shaft as the penis is pulled through, eliminating the need for window creation or complex bilateral flap rotation.[1]
Indications
- Paraffin-induced sclerosing lipogranuloma — the prototype indication (all 49 patients in the Murányi series)[1]
- Requires intact, uninvolved scrotal skin — contraindicated if foreign material has infiltrated the scrotum
- Circumferential penile shaft defect after radical excision
- Conceptually extensible to other circumferential-loss etiologies (Fournier's, circumcision injury, oncologic excision), though the published evidence is paraffinoma only
Operative Technique
1. Circumferential incisions and lipogranuloma excision
- Two circumferential incisions — subcoronal and at the penoscrotal junction
- All lipogranuloma-involved skin + subcutaneous tissue between them excised to Buck's fascia; shaft fully denuded
- Meticulous hemostasis
2. Horizontal scrotal incision
- Transverse anterior-scrotal incision 2–3 cm inferior to the penoscrotal junction
- Length of incision matches the circumference needed to accommodate the shaft
3. Subcutaneous tunnel creation
- Tunnel dissected between the horizontal scrotal incision and the proximal penile circumferential incision
- Plane is between scrotal skin / dartos and external spermatic fascia / tunica vaginalis
- Tunnel must be wide enough to accommodate the shaft without compression
- Both lateral pedicles preserved within the scrotal skin — bilateral external-pudendal / anterior-scrotal-artery blood supply maintained
4. Penile pull-through
- The denuded shaft is pulled through the tunnel from the penoscrotal junction, emerging through the horizontal scrotal incision
- Scrotal skin naturally drapes circumferentially around the shaft
5. Subcoronal and dorsal suture lines
- Distal scrotal-skin edge sutured to the subcoronal skin circumferentially
- Where the scrotal-skin edges meet on the dorsal shaft → longitudinal dorsal suture line
- Interrupted absorbable sutures
6. Ventral inverted-V incision and longitudinal closure
- On the ventral side, where the shaft exits the scrotum, make an inverted-V incision in the scrotal skin
- Inverted V serves two purposes:
- Creates a penoscrotal angle — prevents scrotal-skin migration onto the ventral shaft (webbing)
- Converts the horizontal scrotal incision into a vertical scar line
- This step adapts the Shin inverted-V principle that eliminated the T-junction necrosis seen with traditional bilateral flaps[4]
7. Donor-site closure
- Remaining scrotal skin closed primarily
- Testes covered by posterior + lateral scrotal skin
How It Differs From Other Scrotal-Flap Techniques
| Feature | Murányi tunnel | Fakin bipedicled[6] | Jeong bilateral[3] | Shin inverted-V[4] |
|---|---|---|---|---|
| Flap design | Tunnel pull-through | Central window in flap | Two separate hemiscrotum flaps | Two hemiscrotum flaps |
| Staging | Single | Single | Single | Single |
| Dorsal suture line | Longitudinal dorsal | Circumferential at base + coronal | T-style at corona | Dorsal only |
| Ventral closure | Inverted V → longitudinal | Circumferential | T-style (necrosis-prone) | Inverted V (end-to-end) |
| Tunnel creation | Yes (defining feature) | No | No | No |
| Series size | 49 | 43 | 17 | 34 (14 inverted-V) |
Outcomes — Murányi Series (n = 49)
Perioperative (2017–2020)[1]
- All paraffin-induced sclerosing lipogranuloma; all single-stage
Complications (Clavien-Dindo)
- Overall complication rate 26.5% (13 / 49)
- Grade 1 (no intervention): 5 events
- Grade 2: 0
- Grade 3a (bedside / non-GA procedure): 8 events
- Grade 3b (intervention under GA): 1 event
- Grade 4–5: 0 (no life-threatening complications, no deaths)
Patient-Reported Outcomes (n = 30 questionnaire respondents)
| Outcome | Result |
|---|---|
| Surgical success | 90% (27 / 30) |
| Intercourse ability | 100% |
| Erectile dysfunction | 6.7% (2 / 30) |
| Pain / tension on erection | 10% (3 / 30) |
| Premature ejaculation | 3.3% (1 / 30) |
| Penile lymphedema | 3.3% (1 / 30) |
Comparative Context
| Outcome | Murányi (n = 49) | Fakin bipedicled (n = 43) | Mendel bilateral (n = 22) |
|---|---|---|---|
| Overall complication | 26.5% | ~ 40% (combined minor)[6] | ~ 50% (early + late)[7] |
| Wound dehiscence | included in CD 3a | 19% | 31.8% |
| Erectile dysfunction | 6.7% | 0% reported | n/r |
| Pain / tension on erection | 10% | n/r | n/r |
| Intercourse ability | 100% | 100% | n/r |
| Patient satisfaction | 90% success | 4.37 / 5 | 8 / 10 global |
Single-stage vs two-stage data (Lumbiganon n = 42)[8]
- Postoperative fever — single-stage 56.5% vs two-stage 8.3% (RR 6.78, 95% CI 1.01–43.83)
- Complication-free — single-stage 43.5% vs two-stage 83.3% (RR 0.53, 95% CI 0.31–0.89)
- Hospital stay — single-stage 7.4 ± 3.2 d vs two-stage 10.9 ± 1.6 d
The Murányi tunnel complication rate (26.5%) sits between Lumbiganon's traditional single-stage (~ 56.5%) and two-stage (~ 16.7%), suggesting the tunnel + inverted-V modifications mitigate some of the historical single-stage complication burden.[1][8]
Advantages
- Single-stage — avoids second operation and psychological burden of a buried penis
- Simplified flap design — no central window or complex bilateral rotation
- Eliminates the T-junction — inverted-V ventral closure avoids the necrosis-prone T-style anastomosis
- Preserved bilateral blood supply — both external-pudendal pedicles intact within the scrotal tunnel
- Natural skin draping — scrotal skin conforms to the shaft as it passes through the tunnel
- Suitable when residual foreign material on corpora — intrinsic flap blood supply tolerates a graft-hostile bed
Disadvantages and Limitations
- Requires intact scrotal skin — contraindicated if foreign material has infiltrated the scrotum
- Pain / tension on erection (10%) — tunnel configuration may tether at the penoscrotal junction
- Erectile dysfunction (6.7%) — higher than Fakin's 0%, possibly from tunnel constriction or nerve injury
- High CD 3a rate — 16.3% required bedside intervention
- Hair-bearing potential — variable
- Testicular ascension / scrotal volume reduction — not specifically reported in Murányi but a known scrotal-flap complication[7]
- Single-etiology evidence — all 49 patients were paraffinoma; applicability to other etiologies is extrapolated
Adjunctive Refinements
Kim Y-V advancement for length preservation
Y-V advancement at the dorsal penile base + partial suspensory ligament resection added to a bipedicled scrotal flap. n = 5 — prevented penile shortening with universal patient satisfaction.[9]
Shin inverted-V anastomosis
Direct comparison (n = 34) of T-style vs inverted-V ventral closure — 100% flap survival with no ventral skin necrosis in the inverted-V group. The Murányi technique incorporates this principle in step 6.[4]
Kang single-stage NPWT + dermal substitute + STSG
For paraffinoma patients who lack adequate scrotal skin or prefer a graft pathway — NPWT + Matriderm Flex + STSG single-stage. n = 11, 90.9% near-complete take, satisfaction 37 / 45.[10]
Patient Selection — When Murányi Wins
| Choose Murányi tunnel | Choose two-stage scrotal flap | Choose Fakin bipedicled |
|---|---|---|
| Circumferential paraffinoma defect with intact scrotal skin | Contaminated / actively infected bed | Surgeon comfort with central-window technique |
| Single-stage preferred | Concern about flap viability (prior scrotal surgery, RT) | Residual material doesn't dictate flap-vs-graft choice |
| Residual foreign material on corpora | Patient can tolerate two operations | Single-stage with similar reliability |
| Surgeon experienced with tunnel dissection | Lower complication rate prioritized |
Key Takeaways
- The subcutaneous tunnel and inverted-V ventral closure are the two defining innovations
- Single-stage, simpler dissection than Fakin or Jeong bilateral approaches
- 100% intercourse preservation; ED 6.7%, pain on erection 10% — counsel patients explicitly
- Half of the complications are CD 3a (bedside) — expect a meaningful rate of wound issues even with the modifications
- Currently the largest published single-institution single-stage paraffinoma series
Cross-references
- Bipedicled Anterior Scrotal Flap (Fakin) — central-window single-stage variant
- Penile Skin Grafting — graft alternative including Kang NPWT + dermal-substitute protocol
- Penile Reconstruction — full decision framework
- Scrotal Reconstruction — scrotal donor-site considerations
- Foundations — Plastic Surgery Principles
References
1. Murányi M, Varga D, Kiss Z, Flaskó T. "A New Modified Bipedicle Scrotal Skin Flap Technique for the Reconstruction of Penile Skin in Patients With Paraffin-Induced Sclerosing Lipogranuloma of the Penis." J Urol. 2022;208(1):171–178. doi:10.1097/JU.0000000000002480
2. Napolitano L, Marino C, Di Giovanni A, et al. "Two-Stage Penile Reconstruction After Paraffin Injection: A Case Report and a Systematic Review of the Literature." J Clin Med. 2023;12(7):2604. doi:10.3390/jcm12072604
3. Jeong JH, Shin HJ, Woo SH, Seul JH. "A New Repair Technique for Penile Paraffinoma: Bilateral Scrotal Flaps." Ann Plast Surg. 1996;37(4):386–93. doi:10.1097/00000637-199610000-00007
4. Shin YS, Zhao C, Park JK. "New Reconstructive Surgery for Penile Paraffinoma to Prevent Necrosis of Ventral Penile Skin." Urology. 2013;81(2):437–41. doi:10.1016/j.urology.2012.10.017
5. McLaughlin MM, Abbassi B, Pribaz JJ. "Bipedicled Scrotal Flap for Penile Resurfacing." Plast Reconstr Surg. 2024;153(4):935–942. doi:10.1097/PRS.0000000000010811
6. Fakin R, Zimmermann S, Jindarak S, et al. "Reconstruction of Penile Shaft Defects Following Silicone Injection by Bipedicled Anterior Scrotal Flap." J Urol. 2017;197(4):1166–1170. doi:10.1016/j.juro.2016.11.093
7. Mendel L, Neuville P, Allepot K, et al. "Bilateral Pedicled Scrotal Flaps as an Alternative to Skin Graft in Penile Shaft Defects Repair." Urology. 2023;176:206–212. doi:10.1016/j.urology.2023.03.025
8. Lumbiganon S, Pachirat K, Sirithanaphol W, et al. "Surgical Treatment of Penile Foreign Body Granuloma: Penile Shaft Reconstruction With Single- Versus Two-Stage Scrotal Flap Techniques." Int J Urol. 2023;30(8):681–687. doi:10.1111/iju.15209
9. Kim SW, Yoon BI, Ha US, et al. "Treatment of Paraffin-Induced Lipogranuloma of the Penis by Bipedicled Scrotal Flap With Y-V Incision." Ann Plast Surg. 2014;73(6):692–5. doi:10.1097/SAP.0b013e31828637d3
10. Kang D, Hong SE, Kim YH. "Single-Stage Penile Resurfacing for Foreign Body Granuloma: A Simplified Negative Pressure Wound Therapy-Assisted Protocol With Dermal Substitute." Urology. 2026. doi:10.1016/j.urology.2026.04.013