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Flaps in Genitourinary Reconstruction

A flap is tissue transferred with vascular supply retained through a pedicle or restored by microvascular anastomosis; a graft is transferred without its own vascular supply. Flaps are selected when the recipient site is inadequately vascularized for graft take, when bulk or structural support is required, or when the defect is too large or complex for simpler reconstruction.

Flap Classification Overview​

Every classification axis below descends directly from the layered, tiered-perfusion anatomy of the skin. See the Skin anatomy page for the layers, vascular plexuses, and biomechanics that the terms here refer to. Flaps are classified along several intersecting axes:

AxisCategories
Blood supplyRandom (subdermal plexus, no named vessel) · Axial (named artery along flap axis) · Perforator (cutaneous perforator traversing fascia, sometimes muscle, from a source artery)[14][15]
Tissue compositionCutaneous · Fasciocutaneous · Myocutaneous · Adipofascial · Omental
MovementAdvancement · Rotation · Transposition · Interpolation
Transfer methodPedicled (continuous vascular connection) · Free (microvascular anastomosis at recipient site)

By vascular pattern, Nakajima's classification splits cutaneous flaps into five types (cutaneous, fasciocutaneous, adipofascial, septocutaneous and musculocutaneous), with the fasciocutaneous group further divided into six subtypes by their input to the fascial plexus.[11] In GU reconstruction, fasciocutaneous and myocutaneous flaps predominate. Most pedicled flaps used in perineal and pelvic reconstruction are axial, based on named vessels with reliable anatomy.

A separate axis classifies flap elevation by cutaneous and vascular continuity: a peninsula flap retains both cutaneous and vascular continuity with the donor site; an island flap divides cutaneous continuity while preserving the vascular pedicle; and a microvascular free flap interrupts both, then re-establishes vascular continuity by anastomosis at the recipient site. This terminology distinguishes a true island flap from a skin island or paddle carried on an underlying muscle or fascial flap, though usage varies across the flap literature.[32]

Vascular Basis of Flap Design — Angiosome and Perforasome​

Two anatomic models predict how far a flap can reach beyond its named vessel before it outruns its blood supply.

The angiosome concept (Taylor & Palmer, 1987) describes three-dimensional vascular territories supplied by source arteries and their accompanying veins.[12] In experimental and selected clinical observations, a perforator's clinical territory could extend into that of an adjacent perforator.[12][13] Actual perfusion, venous drainage, prior surgery and the chosen flap still need assessment.

The perforasome theory (Saint-Cyr, 2009) refined this to the territory of an individual perforator and added the rules that govern flap axis:[14]

  • Each perforasome links to its neighbors through direct linking vessels (true parallel anastomoses) and indirect linking vessels (connections through the subdermal plexus).
  • The vascular axis of a flap follows the axiality of the linking vessels, so the flap is oriented along them.
  • Perforators near a joint direct flow away from the joint, and mid-trunk perforators have multidirectional flow.
  • Both the subdermal plexus and the deep fascia contribute to flap perfusion.

Main source arteries may be predictable, but individual perforators vary in size and position. Handheld Doppler or selected vascular imaging can assist planning, with intraoperative reassessment and an alternative design if the expected perforator is unsuitable.[15] These principles underwrite the propeller and perforator flaps used in perineal and genital reconstruction (PMTP, SCIP, IGAP or IPAP, EPAP).

Random Pattern Flap Design Principles​

Some local genital and perineal flaps in this library, including certain rhomboid, bilobed, rotation and advancement designs, are random-pattern flaps supplied through a broad tissue base and the subdermal network. Do not place every penile or preputial or scrotal flap in this category: their vascularized fascial pedicles or named perforators may make them axial or perforator-based designs. Perfusion can decline toward a random flap's tip, but neither a linear fall nor a single dominant necrosis mechanism applies to every design.[16][17]

Length-to-width ratio​

Traditional length-to-width teaching varies by location and flap design.[17] Stell's pig random-flap experiments suggested limiting length to about base width and roughly 12.5 cm.[17] Human laser-speckle observations found a relation between ratio and perfusion, while another pig experiment found absolute length and thickness more predictive than the ratio alone. Assess the actual vascular base and tissue; a fixed 1:1, 2:1 or 3:1 prescription is not supported.[18][31]

Geometry — the arbor principle​

A large area can survive on a narrow base with a short pedicle, but not on a long narrow pedicle: blood flows radially from the base in a tree-foliage ("arbor") pattern. Small random flaps are broadened immediately adjacent to a short, narrow base and are not drawn as long rectangles.[19]

Orientation to relaxed skin tension lines​

Place closure lines parallel to RSTLs wherever possible. Parallel wounds need less force to close, retract less, and benefit more from undermining.[20] In a finite-element model of tissue-expanded advancement flaps, stress was lower with advancement perpendicular to RSTLs.[40] Incisions along cosmetic-unit junctions give the best scar quality. (See the Skin biomechanics section.)

Undermining — technique and extent​

Undermining lowers closure tension up to a point of diminishing returns:

  • In a cadaveric A-to-T flap study, undermining to about three times the defect diameter reduced closure tension, with little additional reduction beyond that distance.[21]
  • On the scalp, 5 cm of subgaleal undermining achieved a mean 83% reduction in closing tension relative to 1 cm of undermining, and 15 cm reached 92% (20 scalp flaps in 10 patients). The further gain was statistically significant but clinically modest.[22]
  • Undermine in the subcutaneous plane (above the deep fascia for most sites) to keep the subdermal plexus with the flap.

Tension and blood flow​

There is an inverse relationship between closing tension and flap blood flow.[23] The frequently quoted 250 g necrosis signal came from 27 piglet random flaps with impaired blood supply.[23] Design generously and offload tension as anatomy permits.[21]

Preserve the subdermal plexus​

The subdermal plexus is the lifeline of a random flap:

  • Avoid unplanned thinning that divides the flap's vascular network.[24] A porcine study of 5×10 cm random flaps reported a mean surviving area of 95.5% for standard flaps and 64.9% for thinned flaps.[24]
  • When de-epithelializing a buried flap, preserve the vascular dermis where the design requires it.[25] In 12 cadaveric hemi-DIEP flaps, the mean perfusion difference after dermis removal was 25.9%.[25]
  • Preserve the subdermal vascular plexus and avoid cautery injury to it; planned thinning depends on the flap design and vascular plane.[24]

The delay phenomenon​

In selected designs, a surgical delay (staged partial incision or elevation before transfer) has been described to improve perfusion and survival in animal models.[27] In a retrospective pediatric tissue-expansion cohort, delayed flaps were narrower-based and had a partial-loss rate comparable to conventional flaps (17 delay procedures among 66 in total).[26] In a 38-rat random-flap model, distal VEGF increased at day 3 and perfusion after day 5, with less average necrosis after a five-day interval.[27][28] Microneedling preconditioning remains experimental.[29]

Pharmacologic adjuncts​

In a review of rat dorsal random-flap experiments, several agents, including pentoxifylline, sildenafil and adrenergic antagonists, were studied for distal necrosis.[30] Flap design, vascular assessment and defect-specific planning remain central.

Summary​

PrincipleBest practiceRationale
Length-to-widthConsider site-specific dimensionsHuman and animal studies give no fixed genital ratio[17][18][31]
ShapeBroaden adjacent to a short, narrow base (arbor)Radial flow from base; long narrow pedicles fail[19]
OrientationAlign closure with RSTLs / cosmetic-unit junctionsLess tension and retraction; better scars[20]
UnderminingEnough to reduce closure tension while preserving the vascular plane[21][22]—
TensionMinimize and assess perfusionThe >250 g finding was in piglets with impaired flow[23]
ThicknessPreserve the vascular plane; thinning is design-dependentUnplanned thinning harmed experimental random flaps[24]
De-epithelializationPreserve vascular dermis where required[25]—
DelayConsider selectively; interval depends on flap and patientFive-day benefit was demonstrated in a rat model[26][27]

Geometric Plasty Techniques​

Several reconstructive maneuvers rearrange local tissue through defined geometric patterns instead of moving tissue from a distant donor. These are part of the flap toolkit and appear repeatedly in GU reconstructive practice:

TechniquePrinciplePrimary GU role
Y-V plastyY-shaped incision → V-shaped closure; advances triangular flap into contracted segment to lengthen perimeterRefractory bladder neck contracture, VUAS after radical prostatectomy
V-Y advancementV-shaped incision → Y-shaped closure; advances triangular flap to cover a defectBuried penis / penile lengthening (suprapubic V-Y); vulvar reconstruction (pubolabial, medial thigh, gluteal V-Y); scrotal and perineal coverage; perineoplasty for lichen-sclerosus introital stenosis; episiotomy-dehiscence repair
Z-plastyTwo transposed triangular flaps; reorients the scar by 90° in an ideal 60° design, lengthens along the original axis (theoretical gain about 75% for an equal-limb 60° design; actual gain is smaller), and breaks linear contractures[37]Pediatric genital reconstruction (hypospadias / chordee / penoscrotal webbing / bifid scrotum); foreskin Z-plasty for phimosis; frenuloplasty; transverse vaginal septum (Garcia / Grünberger); iatrogenic vaginal constriction; posterior-fourchette dyspareunia (Plymouth Procedure)
Rhomboid (Limberg) flapRhombic transposition flap (60° / 120°); 1:1 length-to-width ratio; random vascularization; flap chosen along the line of maximal extensibilitySmall posterior / commissure vulvar defects (bilateral Limberg); epispadias-exstrophy penile elongation; scrotal SCC / EMPD reconstruction
Bilobed flapDouble-transposition flap with two sequential lobes around a shared pivot (Zitelli 90–100° arc); distributes tension across two donorsVulvoperineal defects spanning urogenital + anal triangles (bilobed PAP flap); deep pelvic / perineal defects after APR / exenteration / Fournier's (bilobed gracilis); perineal-body reconstruction after fourth-degree obstetric injury
Propeller flapIsland flap rotated 90–180° around a vascular pedicle; the Tokyo Consensus includes subcutaneous-pedicled, perforator-pedicled and supercharged designs[42]; freestyle designAesthetic penoscrotal resurfacing (IPAP gluteal-fold propeller); vulvar reconstruction (IPAP, gull-wing, lotus petal, perineal-perforator switch); extensive perineal defects after Fournier's / ELAPE / exenteration (PMTP, vPMT, DEPAP, SCIP, EPAP); perineal urethrostomy revision
Lotus petal flapGluteal-fold/internal-pudendal-territory fasciocutaneous flap; donor scar may be concealedSelected vulvar, pelvic-floor and posterior-perineal reconstruction; options for neovaginal or scrotal coverage depend on defect and pedicle

Y-V plasty is a local tissue rearrangement option for selected refractory bladder-neck or anastomotic stenosis.

Flap Index​

Each flap below has a dedicated page with detailed anatomy, harvest technique, GU applications, outcomes, and limitations. The table is the navigation entry point; each flap name links to its dedicated page for full detail.

FlapTypeVascular PedicleCompositionPrimary GU Applications
Pedicled penile/preputial skinPedicled; fasciocutaneousVascularized dartos fascia with superficial penile cutaneous supplySkin + dartos fasciaAnterior urethroplasty, hypospadias, penile shaft coverage
Radial Forearm Free Flap (RFFF)Free; fasciocutaneousRadial artery + venae comitantes / cephalic v.Thin skin + deep fascia (± LACN nerve)Phalloplasty (tube-in-tube), neourethroplasty
GracilisPedicled or free; myocutaneousProfunda femoris or medial circumflex femoral a. (dominant supply varied in 30 gracilis dissections)[41]Gracilis muscle ± skin paddlePerineal/vaginal reconstruction, neovagina, scrotal reconstruction, sphincter reinnervation
Anterolateral Thigh (ALT)Free or pedicled; perforator/fasciocutaneousDescending branch lateral circumflex femoral a.Skin + fat ± fascia ± VL muscleLarge perineal/vaginal defects, phalloplasty (select centers), pelvic reconstruction
VRAMPedicled; myocutaneousInferior epigastric a.Rectus abdominis muscle + vertical skin paddlePelvic floor, perineal/vaginal defects post-cystectomy/exenteration
Omental flapPedicled or freeRight or left gastroepiploic a.Omentum (adipose + vascular)BMG ureteroplasty, urethrovaginal fistula, pelvic dead space obliteration
Peritoneal flapPedicledPeritoneal perforatorsPeritoneumUreteral onlay/wrap, Mitrofanoff adjunct
Vastus lateralisPedicled or free; myocutaneousDescending branch lateral circumflex femoral a.Vastus lateralis muscle ± skinPerineal/gluteal defects, pelvic dead space, failed gracilis territory
Superficial Circumflex Iliac Artery Perforator (SCIP)Free or pedicled; perforatorSuperficial circumflex iliac a. (branch of femoral a.)Thin skin + subcutaneous fat ± fascia / iliac bone / lymph nodes (chimeric)Selected urethral reconstruction in phalloplasty; one center reported complete SCIP urethral-flap loss in 5/33 simultaneous ALT-shaft/SCIP-urethra cases, 1/4 secondary SCIP urethral reconstructions after failed RFFF urethra, and 2/8 bilateral SCIP reconstructions. The center subsequently moved away from routine ALT-shaft/SCIP-urethra pairing[35]; penile shaft; perineo-scrotal coverage after Fournier's; vulvar reconstruction; vesicocutaneous fistula; vascularized lymph node transfer
Blandy flapPedicled local tissueVaginal submucosal base (female) or posterior perineal skin base (male)Anterior vaginal wall (female); perineal skin with scrotal extension when needed (male)Selected female urethral stricture repair; male perineal urethrostomy for complex anterior stricture[38][39]
Martius flapPedicled; adipofascialPosterior labial a. (internal pudendal a.) or anterior labial a.Labial fibroadipose pad; muscle usually preserved in the modified Martius flap[43]Urethrovaginal/vesicovaginal fistula repair, female urethral reconstruction
Labia majora fasciocutaneousPedicled; fasciocutaneousPosterior or anterior labial a.Full-thickness labial skin + fat + fasciaComplex VVF / UVF with vaginal-wall deficit; vaginal wall reconstruction
Medial thigh flapPedicled; fasciocutaneousUpper medial thigh vascular plexus (obturator, external pudendal, medial circumflex femoral)Skin + fat ± fasciaSelected post-Fournier perineal/scrotal coverage; other local and regional options also used
Singapore / pudendal thighPedicled; fasciocutaneousPosterior labial a. (internal pudendal a.)Medial thigh skin + adductor fasciaSelected vaginal reconstruction (sometimes bilateral for neovagina); posterior perineum
PMTP propellerPedicled; perforator propeller (180° rotation)Deep femoral a. perforatorSkin + fat (island)Extensive perineal / perineoscrotal defects (256 cm² mean)
Island groin flapPedicled; axial fasciocutaneousSuperficial circumflex iliac a. (named axial vessel)Skin + subcutaneous fat ± fasciaSingle-stage scrotal-defect coverage (Sahai 30-yr experience); paired with bilateral thigh flaps for total scrotal loss
MCFAPPedicled; perforator (muscle-sparing alternative to gracilis MC)Musculocutaneous perforators of medial circumflex femoral a.Skin + fat (gracilis preserved)Moderate scrotal defects after Fournier's where bulk is not required (Coskunfirat 2011)
IGAP / gluteal-foldPedicled; perforator / propeller (90–180° rotation)IGA / SGA perforators ± IGA descending branch ± PFA perforatorsSkin + fat ± fascia (gluteus preserved)Combined perineal / pelvic + scrotal coverage; aesthetic penoscrotal resurfacing (IPAP gluteal-fold propeller, Han 2018); posterior perineal defects
Posterior thigh flapPedicled; fasciocutaneousDescending IGA branch + PFA perforatorsPosterior-thigh skin + fat ± fasciaComplex pelvic / perineal reconstruction when laparotomy avoided; pre-existing dual diversion; salvage when VRAM / gracilis unavailable
EPAP hemi-scrotalPedicled; perforator; sensateExternal pudendal a. perforatorHemi-scrotal skin + dartosCircumferential penile-shaft resurfacing (Tsukuura 2025); hemi-scrotal reconstruction; sensate penile coverage reported at seven months in one case[9]
Bladder flapPedicled; full- or partial-thickness bladder wallVesical arterial supply, depending on designUrothelium-lined bladder wall ± detrusorBoari flap, often with psoas hitch, for selected ureteral defects; selected fistula, female urethral and bladder-neck repairs. Reach and outcomes are technique- and patient-specific
Y-V plastyLocal tissue rearrangementNative bladder vasculatureBladder wall (triangular advancement flap)Refractory bladder neck contracture; VUAS after radical prostatectomy

Flap Selection Principles by Indication​

Urethral strictures (anterior urethra)​

  • Vascularization matters. Assess donor skin, dartos pedicle and recipient bed for the selected penile-flap design.[1] In males with lichen-sclerosus-related penile urethral stricture, do not use genital skin for augmentation penile urethroplasty .[34]
  • Onlay versus tube: the McAninch–Morey observational cohort reported 7/54 onlay (13%) versus 7/12 tubularized (58%) recurrences. Different defect severity and selection prevent declaring every onlay superior.[2]
  • Failed urethroplasty or obliteration: consider vascularized tissue when the bed cannot support a graft.
  • Sexual function. Assess each patient's baseline and follow-up.[1]

Bladder neck contracture / VUAS​

  • Recurrent or complex stenosis: choose reconstruction by anatomy, continence and treatment history. For treatment-refractory bladder-neck stenosis after benign outlet surgery, EAU 2026 recommends Y-V plasty or T-plasty and counseling about de novo incontinence . For obliterative or treatment-refractory VUAS, it recommends redo vesicourethral anastomosis in non-irradiated men or irradiated men with adequate bladder function .[34]
  • Robotic Y-V and other bladder-neck reconstructions: a small selected Y-V series reported feasibility and patency without proving equivalence to open repair.[3] A 2024 review of ten heterogeneous retrospective series (119 men; study median follow-up 5–23 months) reported pooled patency in 95/119 (80%) and de novo incontinence in 8/47 (17%) men with usable baseline data.[44]
  • ICG fluorescence: may assist selected intraoperative localization.
  • Transurethral mucosal realignment: Abramowitz described an endoscopic incision of the scar with transurethral suturing of healthy bladder mucosa across the defect, which the authors compare to a Y-V plasty; it is not a bladder-wall advancement flap. In 19 patients (median follow-up 6 months), success (passage of a 17 Fr flexible cystoscope at 4 months) was 89% after one procedure and 100% after a second.[4]

Vesicovaginal and urethrovaginal fistula​

  • Selected simple VVF: direct repair may suffice without mandatory interposition.
  • Compromised or recurrent VVF: consider Martius or omental interposition according to route, tissue quality and defect; neither is mandatory for every case. A 2024 review of heterogeneous VVF repairs found no statistically significant improvement in fistula cure with interposition; evidence is insufficient to determine benefit in specific complex defects.[36]
  • VVF with vaginal wall deficit: labia majora fasciocutaneous flap. The flap provides both fistula interposition and vaginal wall tissue[5]
  • Recurrent VVF after prior interposition: reassess defect, tissue viability, route and need for another vascularized option.
  • Single-layer annular vaginal flap: Tang's retrospective series of 57 women described this transvaginal technique.[6] First-time success was 82.3% in the transvaginal group (17 patients) and 75% in the transvesical group (40 patients).[6]

Perineal / genital coverage (Fournier's, extensive defects)​

  • Active Fournier's gangrene first needs debridement and source control. Protect exposed structures during wound care, then select closure, graft or flap once the wound and patient permit definitive reconstruction.
  • Flap outcomes: Alammar's 2026 review included 619 selected patients and 625 flaps. It reported flap loss in 1.6% of the published cases.[7]
  • Regional choices include medial thigh, pudendal thigh, ALT and gracilis in that review. Choice of regional flap depends on defect size and depth, exposure, local tissue and surgical expertise.[7]
  • Perforator propeller options (PMTP, DEPAP, SCIP, EPAP) can cover selected defects without microvascular anastomosis; their reach and venous risks vary.
  • Recorded reasons for flap use in that selected review included exposed structures (52%), function (39%) and cosmesis (4%).[7]
  • Extensive oncologic perineal defects (planning framework): an editor-proposed three-type scheme can help frame multidisciplinary discussion of defect extent before reconstruction: Type 1 (anterior perineum up to the pubis, anus spared, subdivided by urethral preservation or resection); Type 2 (anus and posterior perineum, anterior perineum spared, subdivided by whether pelvic clearance accompanies anal resection); and Type 3 (most or all of the perineum with total pelvic exenteration).[33]

Penile shaft coverage​

  • Modified bilateral scrotal flap ("butterfly" design) . It restores penile skin length from bilateral scrotal donors. A technique report of 7 patients noted small areas of flap necrosis in 2[8]
  • External Pudendal Artery Perforator (EPAP) hemi-scrotal flap. It provides sensate, thin, pigmented coverage of circumferential penile shaft defects; a single case report described a wider rotation arc than conventional scrotal flaps[9]
  • SCIP flap. A thin free or pedicled flap option with a concealed inguinal donor site; the cited phalloplasty series used pedicled SCIP flaps.[35]

Vulvovaginal reconstruction (oncologic)​

  • Small defects: rhomboid (Limberg) flap or V-Y advancement
  • Moderate defects: lotus petal or superficial external pudendal artery flaps based on distinct vascular territories
  • Large defects or full vaginal reconstruction: bilateral Singapore (pudendal thigh) flaps or VRAM or gracilis myocutaneous
  • Compound perineal and vulvar defects: bilobed pudendal artery perforator flap preserves distinct tissue character of urogenital and anal triangles[10]

Postoperative Care​

Recipient-site positioning, pressure offloading, drain management and serial flap monitoring are shared across reconstruction of pelvic and perineal defects with gracilis, VRAM, posterior-thigh, lotus-petal or IPAP flaps; see Pelvic and Perineal Flap Postoperative Care for the shared workflow and its evidence limits.

References​

1. 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

2. McAninch JW, Morey AF. Penile circular fasciocutaneous skin flap in 1-stage reconstruction of complex anterior urethral strictures. J Urol. 1998;159(4):1209–13. doi:10.1016/s0022-5347(01)63558-4

3. Granieri MA, Weinberg AC, Sun JY, Stifelman MD, Zhao LC. Robotic Y-V plasty for recalcitrant bladder neck contracture. Urology. 2018;117:163–165. doi:10.1016/j.urology.2018.04.017

4. Abramowitz DJ, Balzano FL, Ruel NH, Chan KG, Warner JN. Transurethral incision with transverse mucosal realignment for the management of bladder neck contracture and vesicourethral anastomotic stenosis. Urology. 2021;152:102–108. doi:10.1016/j.urology.2021.02.035

5. Gupta P, Kalra S, Dorairajan LN, et al. Labia majora fasciocutaneous flap reconstruction in complex urogynecological fistulas with vaginal deficit — a versatile approach. Urology. 2022;167:241–246. doi:10.1016/j.urology.2022.05.017

6. Tang M, Li P, Wang C, Zhang Q, Meng X. Clinical application of single-layer annular vaginal flap in transvaginal repair for vesicovaginal fistula. World J Urol. 2023;41(1):249–255. doi:10.1007/s00345-022-04222-w

7. Alammar A, Laing K, Somasundaram J, Wallace DL, Rogers AD. Flap reconstruction following Fournier's gangrene: a systematic review of techniques and outcomes. Burns. 2026;52(3):107888. doi:10.1016/j.burns.2026.107888

8. Yao H, Zheng D, Xie M, et al. A modified bilateral scrotal flap for penile skin defect repair. J Vis Exp. 2022;(189). doi:10.3791/64017

9. Tsukuura R, Engmann T, Miyazaki T, Yamamoto T. The sensate external pudendal artery perforator (EPAP) hemi-scrotal flap for the circumferential skin defect of the penile shaft: a case report and literature review. Microsurgery. 2025;45(7):e70123. doi:10.1002/micr.70123

10. Yun IS, Lee JH, Rah DK, Lee WJ. Perineal reconstruction using a bilobed pudendal artery perforator flap. Gynecol Oncol. 2010;118(3):313–6. doi:10.1016/j.ygyno.2010.05.007

11. Nakajima H, Fujino T, Adachi S. A new concept of vascular supply to the skin and classification of skin flaps according to their vascularization. Ann Plast Surg. 1986;16(1):1–19. doi:10.1097/00000637-198601000-00001

12. Taylor GI, Corlett RJ, Dhar SC, Ashton MW. The anatomical (angiosome) and clinical territories of cutaneous perforating arteries: development of the concept and designing safe flaps. Plast Reconstr Surg. 2011;127(4):1447–1459. doi:10.1097/PRS.0b013e318208d21b

13. Morris SF, Taylor GI. Predicting the survival of experimental skin flaps with a knowledge of the vascular architecture. Plast Reconstr Surg. 1993;92(7):1352–61. PMID 8248411

14. Saint-Cyr M, Wong C, Schaverien M, Mojallal A, Rohrich RJ. The perforasome theory: vascular anatomy and clinical implications. Plast Reconstr Surg. 2009;124(5):1529–1544. doi:10.1097/PRS.0b013e3181b98a6c

15. Morris SF, Tang M, Almutairi K, Geddes C, Yang D. The anatomic basis of perforator flaps. Clin Plast Surg. 2010;37(4):553–70, xi. doi:10.1016/j.cps.2010.06.006

16. Chen H, Chen B, Li B, et al. Gastrodin promotes the survival of random-pattern skin flaps via autophagy flux stimulation. Oxid Med Cell Longev. 2021;2021:6611668. doi:10.1155/2021/6611668

17. Stell PM. The viability of skin flaps. Ann R Coll Surg Engl. 1977;59(3):236–41. PMID 324339

18. Carvalho Brinca AM, de Castro Pinho A, Costa Vieira RJD. Blood perfusion of random skin flaps in humans — in vivo assessment by laser speckle contrast imaging. Dermatol Surg. 2021;47(11):1421–1426. doi:10.1097/DSS.0000000000003164

19. Wexler MR. An arbor flap: the tree-pattern flap, or how narrow may the base of a skin flap be? An experimental study. Plast Reconstr Surg. 1981;68(2):185–94. doi:10.1097/00006534-198108000-00011

20. McGuire MF. Studies of the excisional wound: I. Biomechanical effects of undermining and wound orientation on closing tension and work. Plast Reconstr Surg. 1980;66(3):419–27. doi:10.1097/00006534-198009000-00018

21. Stevens CR, Tan L, Kassir R, Calhoun K. Biomechanics of A-to-T flap design. Laryngoscope. 1999;109(1):113–7. doi:10.1097/00005537-199901000-00022

22. Raposio E, Nordström RE, Santi PL. Undermining of the scalp: quantitative effects. Plast Reconstr Surg. 1998;101(5):1218–22. doi:10.1097/00006534-199804050-00007

23. Larrabee WF, Holloway GA, Sutton D. Wound tension and blood flow in skin flaps. Ann Otol Rhinol Laryngol. 1984;93(2 Pt 1):112–5. doi:10.1177/000348948409300202

24. Yazar S, Guzel MZ, Aydin Y, Arslan H, Demir M. Demonstration of circulation haemodynamics in random pattern thinned skin flap (an experimental study). J Plast Reconstr Aesthet Surg. 2008;61(11):1368–77. doi:10.1016/j.bjps.2007.11.045

25. Laungani AT, Van Alphen N, Christner JA, et al. Three-dimensional CT angiography assessment of the impact of the dermis and the subdermal plexus in DIEP flap perfusion. J Plast Reconstr Aesthet Surg. 2015;68(4):525–30. doi:10.1016/j.bjps.2014.12.004

26. Ha JH, Lee SY, Choi TH, Park SO. Surgical delay increases the survival of expanded random-pattern flap in pediatric patients. Sci Rep. 2023;13(1):19204. doi:10.1038/s41598-023-45852-3

27. Holzbach T, Neshkova I, Vlaskou D, et al. Searching for the right timing of surgical delay: angiogenesis, vascular endothelial growth factor and perfusion changes in a skin-flap model. J Plast Reconstr Aesthet Surg. 2009;62(11):1534–42. doi:10.1016/j.bjps.2008.05.036

28. Jonsson K, Hunt TK, Brennan SS, Mathes SJ. Tissue oxygen measurements in delayed skin flaps: a reconsideration of the mechanisms of the delay phenomenon. Plast Reconstr Surg. 1988;82(2):328–36. doi:10.1097/00006534-198808000-00020

29. Unverdi OF, Coruh A. Effects of microneedle length and duration of preconditioning on random pattern skin flaps in rats. J Plast Reconstr Aesthet Surg. 2020;73(9):1758–1767. doi:10.1016/j.bjps.2020.03.022

30. Üstün GG, Öztürk S, Koçer U. Standardization of the rat dorsal random pattern (McFarlane) flap model and evaluation of the pharmacological agents aiming to salvage partial flap necrosis: a systematic review and a meta-analysis. Ann Plast Surg. 2021;87(6):e145–e152. doi:10.1097/SAP.0000000000002919

31. Memarzadeh K, Sheikh R, Blohmé J, et al. Perfusion and oxygenation of random advancement skin flaps depend more on the length and thickness of the flap than on the width to length ratio. Eplasty. 2016;16:e12. Full text.

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