Grafts in Genitourinary Reconstruction
A free tissue graft is transferred without a vascular pedicle and must acquire support from its recipient bed. A flap arrives with its own blood supply. This distinction matters when choosing between a free mucosal patch, a pedicled skin flap and a vascularized bowel segment.
This page compares donor options and core principles. The linked donor and named-operation pages contain the detailed harvest and reconstruction evidence.
Graft Take: Imbibition and Inosculation
Imbibition (0–48 hours)
Initially, fluid and nutrients diffuse from the recipient bed into the graft. The first one to two days are a useful approximate teaching interval, not a fixed viability clock for every tissue or patient.[12][15]
Inosculation (48 hours – 1 week)
Inosculation describes connections between graft and recipient vessels; neovascularization includes ingrowth of new host vessels. These processes overlap. The classic Converse experiment demonstrated vascular entry by 48 hours in rat skin grafts; it does not prescribe an exact clinical timetable for every GU mucosal graft.[2]
Factors Affecting Graft Take
| Factor | Practical implication |
|---|---|
| Recipient-bed vascularity | Assess actual viable tissue; marked scarring, ischemia or radiation injury may require vascularized reconstruction |
| Contact and drainage | Prevent hematoma, seroma and other collections that separate graft from bed; use appropriate fixation, including quilting where indicated |
| Shear | Plan support and immobilization for the operation and anatomical site; there is no universal 48–72-hour regimen |
| Infection and tissue viability | Debride nonviable tissue and control infection; colonization alone is not synonymous with invasive infection |
| Thickness and preparation | Remove unwanted fat carefully while preserving the required graft layers; neither extreme thinning nor full thickness guarantees take |
| Patient and wound factors | Consider perfusion, smoking, diabetes, nutrition, prior treatment and postoperative wound mechanics |
For skin-graft biology and fixation evidence, see STSG and FTSG. For a poorly vascularized urethral bed, consider the role of vascularized flaps.[10]
BMG ureteroplasty: a graft needs an appropriate vascular environment. Omentum is a commonly used adjunct, but Zhao's initial four-patient series was not a comparison proving that reconstruction without omentum fails. The support and wrapping plan depends on the repair and available tissues; see the operative page.[1]
Quick Reference: Grafts in GU Reconstruction
| Tissue | Donor | Principal role / caution |
|---|---|---|
| Buccal mucosa | Inner cheek | Common urethral graft; selected ureteral augmentation |
| Lingual mucosa | Ventrolateral tongue | Oral donor alternative or supplement; different speech/tongue morbidity |
| Oral-lip mucosa | Inner lip | Selected oral donor; not genital labial tissue |
| Rectal mucosa | Rectum, with transanal harvest | Selected complex salvage; limited comparative and long-term evidence |
| Penile / preputial skin | Healthy penile skin / prepuce | Selected graft or flap applications; specify which, assess hair and avoid genital skin in LS-related urethral strictures |
| Postauricular skin | Behind the ear | Selected alternative skin donor when usual tissues are unsuitable |
| STSG | Epidermis plus part of dermis | Genital/perineal coverage and selected vaginal reconstruction |
| FTSG | Epidermis plus full dermis | Selected coverage; donor closure and revascularization demands matter |
| Bladder mucosa | Bladder | Selected/historical urethral substitute; separate donor morbidity |
| Saphenous vein | Leg | Vascular conduit or prepared patch in selected operations |
| Intestinal segment | Ileum / colon | Usually transferred with its mesenteric blood supply, rather than as a free mucosal graft |
Graft Detail
Buccal Mucosa Graft (BMG)
Buccal mucosa provides hairless, non-keratinizing stratified squamous lining. Oral mucosa is the usual first donor considered when a urethral graft is required and suitable tissue is available. It does not become urothelium after transfer.[8][10]
Assess oral health, previous harvest, mouth opening and the required dimensions. Identify and protect the parotid duct and surrounding structures. Donor closure, bilateral harvest and the choice of buccal versus another oral site require individual planning; the detailed BMG page describes the relevant comparisons.
Lingual Mucosa Graft
Lingual mucosa is an alternative or supplemental oral donor, not simply an inferior fallback. Discuss tongue movement, speech, taste and eating symptoms alongside the different morbidity of cheek harvest. Safe harvest follows the actual ventrolateral anatomy; a choice of surface does not automatically eliminate nerve injury.[10] See Lingual Mucosa.
Labial Mucosa Graft
Here labial means oral lip. Inner-lip mucosa is distinct from the vermilion and from female genital labia. Its use is not inherently female-specific. Restricted donor territory and possible persistent lip discomfort, numbness, salivary or cosmetic changes affect selection.[10] See Oral-Lip Mucosa; identify the exact donor whenever reading a female-urethroplasty report that uses the word “labial.”
Rectal Mucosa Graft
Rectal mucosa is a selected salvage option when adequate oral tissue is unavailable or unsuitable. It has columnar epithelium and requires assessment of both recipient reconstruction and rectal donor morbidity. Transanal endoscopic, robotic and single-port harvests have been described; none is established as universally superior.[3][4][6][7][9]
| Report | Actual population and finding | Main limitation |
|---|---|---|
| Granieri 2019 | 13 reconstructions; two recurrences at median follow-up 13.5 months; no bowel-related complication reported | Small heterogeneous salvage cohort; other complications included glans dehiscence, urethrocutaneous fistula and compartment syndrome |
| Palmer 2016 | Four patients; one recurrence; median follow-up 18 months | Ten months was the time of the recurrence, not median follow-up |
| Howard 2019 | Six urethral and one vaginal stricture; favorable graft take and no reported complications at median 17 months | Not seven urethroplasties; subjective pain comparison with prior cheek harvest is not randomized evidence |
| Emrich Accioly 2022 | One patient; a 21 × 3 cm graft and discharge on day two | Technical feasibility, not an expected graft size or discharge rule for all patients |
| Ozgur 2023 | Two cases describing single-port harvest | Small technical report; does not establish long-term donor safety |
Sources correspond to the named reports.[3][4][6][7][9] Do not sum these potentially overlapping institutional reports to estimate worldwide experience. Absence of a reported bowel complication in small series is not proof of zero risk. Staged graft take has also been illustrated, but early incorporation does not establish durable stricture-free survival.[5]
Product safety: older harvest descriptions used ORISE gel. It was removed from the market in December 2022 because retained material could provoke foreign-body reactions and mass-like changes. It should not be recommended as a current lifting agent.[11] Plan contemporary instrumentation and lifting agents with the colorectal team using current product labeling. See Enterourethroplasty for the distinction between a free mucosal graft and vascularized bowel substitution.
Intestinal Segments
Most bowel segments used for augmentation, diversion or intestinal vaginoplasty retain their mesenteric supply. Sigmoid vaginoplasty is not McIndoe skin-graft vaginoplasty. Mucus and absorption are consequences to manage, not an intrinsic advantage for every urinary reconstruction.
Reservoir configuration, bowel length/location and urine contact determine risks such as acidosis, mucus obstruction, infection, stones and B12 deficiency. The ileocecal valve may contribute to a continence mechanism; it is not automatically a ureteral antireflux mechanism. Use the detailed intestinal-segment page, augmentation principles and diversion principles for selection and lifelong follow-up.
Penile / Preputial Skin Graft
A free preputial graft, a pedicled preputial island flap and tubularization of the native urethral plate are different operations. Duckett is a flap technique; standard TIP does not require a free graft. Circumcision limits preputial availability, but it does not remove all penile skin.
Assess healthy donor tissue and actual hair distribution. Avoid genital skin in LS-related urethral strictures. Single-stage free-graft tubes should not be presented as routine urethral substitutes.[10] See Penile / Preputial Skin.
Saphenous Vein Graft
Vein used as a vascular conduit differs from an opened patch used for another reconstructive purpose. Penile arterial reconstruction is reserved for carefully selected patients with focal arterial disease; penile venous ligation is not recommended as routine ED treatment by the AUA guideline.[14] See Saphenous Vein for the specific applications and limitations.
Posterior Auricular Skin Graft
Postauricular skin is a selected alternative donor. Available area, thickness, hair, pigmentation and closure vary; a concealed location does not guarantee no visible morbidity. Its use is not confined to short pediatric strictures.[10] See Posterior Auricular Skin.
Skin Grafts (STSG and FTSG)
| Property | STSG | FTSG |
|---|---|---|
| Composition | Epidermis and partial dermis | Epidermis and full dermis |
| Immediate recoil after harvest | Generally less | Generally greater |
| Later contraction during healing | Generally greater | Generally less |
| Donor wound | Re-epithelializes from retained structures | Usually closed primarily |
| Hair | Depends on donor and harvest | Depends on donor and preparation |
| Penile coverage | Established option for selected defects | Established option for selected defects |
Neither graft has a guaranteed take rate, minimal contraction in every site or proven universal superiority for penile coverage. Donor, recipient bed, dimensions and postoperative support determine suitability. See the full STSG and FTSG discussions.
For vaginal agenesis, supported dilation is first-line for most patients ready for treatment; McIndoe or other surgery follows informed individualized discussion and still requires postoperative dilation.[13]
Bladder Mucosa Graft
Bladder mucosa is a urothelial donor with historical and selected contemporary applications. Harvest morbidity, tissue handling and outcomes require comparison with other available donors; native urothelium is not automatically the ideal substitute. See Bladder Mucosa.
Tissue-Engineered Grafts & Bioscaffolds
Cell-free matrices and cell-seeded constructs differ in preparation, regulation, recipient-bed requirements and evidence. They should not be treated as interchangeable alternatives to autologous oral mucosa. See Tissue-Engineered Grafts & Bioscaffolds and the relevant guideline restrictions.[10]
Graft Selection Summary
Start with the defect and viable recipient tissue, then compare suitable donors and the morbidity of each. Separate graft versus flap, patch versus tube, skin versus mucosa, and early graft incorporation versus durable function. Use the linked donor pages and named-operation guidance for patient-specific selection rather than choosing from an unconditional “preferred graft” table.
References
1. Zhao LC, Yamaguchi Y, Bryk DJ, Adelstein SA, Stifelman MD. Robot-assisted ureteral reconstruction using buccal mucosa. Urology. 2015;86(3):634–638. doi:10.1016/j.urology.2015.06.006. PMID 26123519
2. Converse JM, Smahel J, Ballantyne DL Jr, Harper AD. Inosculation of vessels of skin graft and host bed: a fortuitous encounter. Br J Plast Surg. 1975;28(4):274–282. doi:10.1016/0007-1226(75)90031-4. PMID 1104028
3. Granieri MA, Zhao LC, Breyer BN, et al. Multi-institutional outcomes of minimally invasive harvest of rectal mucosa graft for anterior urethral reconstruction. J Urol. 2019;201(6):1164-1170. doi:10.1097/JU.0000000000000087.
4. Palmer DA, Marcello PW, Zinman LN, Vanni AJ. Urethral reconstruction with rectal mucosa graft onlay: a novel, minimally invasive technique. J Urol. 2016;196(3):782-786. doi:10.1016/j.juro.2016.03.002.
5. Pagura EJ, Cavallo JA, Zinman LN, Vanni AJ. Rectal mucosa graft take in staged urethroplasty. Urology. 2019;127:e1-e2. doi:10.1016/j.urology.2019.02.023.
6. Emrich Accioly JP, Zhao H, Ozgur I, et al. Single-port, robot-assisted transanal harvest of rectal mucosa grafts for substitution urethroplasty. Urology. 2022;166:1-5. doi:10.1016/j.urology.2022.04.018.
7. Howard KN, Zhao LC, Weinberg AC, et al. Robotic transanal minimally invasive rectal mucosa harvest. Surg Endosc. 2019;33(10):3478-3483. doi:10.1007/s00464-019-06893-w.
8. 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.
9. Ozgur I, Justiniano CF, Wood HM, Gorgun E. Single-port endorobotic rectal mucosa harvest for urethral reconstruction. Dis Colon Rectum. 2023;66(2):e54-e57. doi:10.1097/DCR.0000000000002577.
10. European Association of Urology. Urethral Strictures Guidelines: Tissue Transfer. 2026. Guideline chapter.
11. US Food and Drug Administration. Class 2 Device Recall: Boston Scientific ORISE Gel Submucosal Lifting Agent. December 2022 product-removal update. Recall record.
12. Converse JM, Uhlschmid GK, Ballantyne DL Jr. “Plasmatic circulation” in skin grafts: the phase of serum imbibition. Plast Reconstr Surg. 1969;43(5):495–499. PMID 4889411.
13. ACOG Committee on Adolescent Health Care. Committee Opinion No. 728: Müllerian agenesis: diagnosis, management, and treatment. Obstet Gynecol. 2018;131:e35–e42. doi:10.1097/AOG.0000000000002458.
14. Burnett AL, Nehra A, Breau RH, et al. Erectile dysfunction: AUA guideline. J Urol. 2018;200:633–641. doi:10.1016/j.juro.2018.05.004. Guideline.
15. Younis AS, Abdelmonem IM, Gadullah M, et al. Hydrogel dressings for donor sites of split-thickness skin grafts. Cochrane Database Syst Rev. 2023;8:CD013570. doi:10.1002/14651858.CD013570.pub2.