Composite Biosynthetic Graft for Repair of Long-Segment Tracheal Stenosis: A Pilot In Vivo and In Vitro Feasibility Study.

Pediatric patients who undergo surgery for long-segment congenital tracheal stenosis (LSCTS) have suboptimal outcomes and postsurgical complications. To address this, we propose a biosynthetic graft comprising (1) a porcine small intestinal submucosa extracellular matrix (SIS-ECM) patch for tracheal repair, and (2) a resorbable polymeric exostent for biomechanical support. The SIS-ECM patch was evaluated in vivo in an ovine trachea model over an 8 month period. Concurrently, the biosynthetic graft was evaluated in a benchtop lamb trachea model for biomechanical stability. In vivo results show that SIS-ECM performs better than bovine pericardium (control) by preventing granulation tissue/restenosis, restoring tracheal architecture, blood vessels, matrix components, pseudostratified columnar and stratified epithelium, ciliary structures, mucin production, and goblet cells. In vitro tests show that the biosynthetic graft can provide the desired axial and flexural stability, and biomechanical function approaching that of native trachea. These results encourage future studies to evaluate safety and efficacy, including biomechanics and collapse risk, biodegradation, and in vivo response enabling a stable long-term tracheal repair option for pediatric patients with LSCTS and other tracheal defects.

NF-kappa-B activation unveils the presence of inflammatory hotspots in human gut xenografts.

The single-epithelial cell layer of the gut mucosa serves as an essential barrier between the host and luminal microflora and plays a major role in innate immunity against invading pathogens. Nuclear factor kB (NF-κB), a central component of the cellular signaling machinery, regulates immune response and inflammation. NF-κB proteins are activated by signaling pathways downstream to microbial recognition receptors and cytokines receptors. Highly regulated NF-κB activity in intestinal epithelial cells (IEC) is essential for normal gut homeostasis; dysregulated activity has been linked to a number of disease states, including inflammatory bowel diseases (IBD) such as Crohn's Disease (CD). Our aim was to visualize and quantify spatial and temporal dynamics of NF-κB activity in steady state and inflamed human gut. Lentivirus technology was used to transduce the IEC of human gut xenografts in SCID mice with a NF-κB luminescence reporter system. NF-κB signaling was visualized and quantified using low resolution, intravital imaging of the whole body and high resolution, immunofluorescence microscopic imaging of the tissues. We show that NF-κB is activated in select subset of IEC with low "leaky" NF-κB activity. These unique inflammatory epithelial cells are clustered in the gut into discrete hotspots of NF-κB activity that are visible in steady state and selectively activated by systemic LPS and human TNFα or luminal bacteria. The presence of inflammatory hotspots in the normal and inflamed gut might explain the patchy mucosal lesions characterizing CD and thus could have important implications for diagnosis and therapy.

Post-stapedotomy reparative granuloma following use of acellular porcine small intestinal submucosa.

PURPOSE: There have been multiple proposed etiologies of reparative granuloma following stapes surgery. In this report, we present the first case of post-stapedectomy reparative granuloma following the use of Biodesign (Cook Medical, Bloomington, IN) otologic graft material, an acellular matrix derived from porcine small intestinal submucosa, and review the literature of post-stapes surgery reparative granuloma. PATIENT: 50-year-old woman who developed a reparative granuloma following stapedotomy with acellular porcine intestinal submucosa presenting with profound hearing loss and vertigo. INTERVENTION: Middle ear exploration with excision of granuloma and revision stapedotomy. MAIN OUTCOME MEASURES: Audiologic outcomes as measured by pure-tone air and bone conduction thresholds and word recognition scores. Improvement in vertigo. MAIN FINDINGS: Surgical excision of the reparative granuloma with revision stapedotomy resolved vertigo. Hearing has improved progressively postoperatively. CONCLUSIONS: We report the first case of post-stapedotomy reparative granuloma following the use of acellular porcine intestinal submucosa. Although exact etiology cannot be determined from a single case report, this illustrates the need for careful use of novel foreign graft material. This case additionally confirms that removal of granuloma and inciting materials can salvage serviceable hearing.

Engineering transplantable jejunal mucosal grafts using patient-derived organoids from children with intestinal failure.

Intestinal failure, following extensive anatomical or functional loss of small intestine, has debilitating long-term consequences for children1. The priority of patient care is to increase the length of functional intestine, particularly the jejunum, to promote nutritional independence2. Here we construct autologous jejunal mucosal grafts using biomaterials from pediatric patients and show that patient-derived organoids can be expanded efficiently in vitro. In parallel, we generate decellularized human intestinal matrix with intact nanotopography, which forms biological scaffolds. Proteomic and Raman spectroscopy analyses reveal highly analogous biochemical profiles of human small intestine and colon scaffolds, indicating that they can be used interchangeably as platforms for intestinal engineering. Indeed, seeding of jejunal organoids onto either type of scaffold reliably reconstructs grafts that exhibit several aspects of physiological jejunal function and that survive to form luminal structures after transplantation into the kidney capsule or subcutaneous pockets of mice for up to 2 weeks. Our findings provide proof-of-concept data for engineering patient-specific jejunal grafts for children with intestinal failure, ultimately aiding in the restoration of nutritional autonomy.

A novel histidine-tryptophan-ketoglutarate formulation ameliorates intestinal injury in a cold storage and ex vivo warm oxygenated reperfusion model in rats.

AIM: The present study aims to evaluate protective effects of a novel histidine-tryptophan-ketoglutarate solution (HTK-N) and to investigate positive impacts of an additional luminal preservation route in cold storage-induced injury on rat small bowels. METHODS: Male Lewis rats were utilized as donors of small bowel grafts. Vascular or vascular plus luminal preservation were conducted with HTK or HTK-N and grafts were stored at 4°C for 8 h followed by ex vivo warm oxygenated reperfusion with Krebs-Henseleit buffer for 30 min. Afterwards, intestinal tissue and portal vein effluent samples were collected for evaluation of morphological alterations, mucosal permeability and graft vitality. RESULTS: The novel HTK-N decreased ultrastructural alterations but otherwise presented limited effect on protecting small bowel from ischemia-reperfusion injury in vascular route. However, the additional luminal preservation led to positive impacts on the integrity of intestinal mucosa and vitality of goblet cells. In addition, vascular plus luminal preservation route with HTK significantly protected the intestinal tissue from edema. CONCLUSION: HTK-N protected the intestinal mucosal structure and graft vitality as a luminal preservation solution. Additional luminal preservation route in cold storage was shown to be promising.

Single port laparoscopy combined with vaginal cervicovaginal reconstruction in a patient with congenital atresia of the cervix.

OBJECTIVE: To introduce an innovation that combines single port laparoscopic and Wharton-Sheares-George cervicovaginal reconstruction using a small intestinal submucosa (SIS) graft in a patient with congenital cervical atresia, absence of vagina, and incomplete uterine septum (U2aC4V4). DESIGN: Video article introducing a new surgical technique. SETTING: University hospital. PATIENT(S): A 15-year-old patient with congenital cervical atresia, absence of vagina, and incomplete uterine septum had primary amenorrhea and cyclic lower abdominal pain. The magnetic resonance imaging did not show hematometra and the endometrium was 6 mm when she had lower abdominal pain. INTERVENTION(S): A neovagina (depth, 7 cm; width, 2.5 cm) was created using the Wharton-Sheares-George neovaginoplasty. By single laparoscopy, the bladder was separated from the anterior surface of the uterus. With the mold in the neovagina created by the assistant, the apex of neovagina was opened. Then the lower uterine segment was exposed and incised. A T-shaped intrauterine device was connected to an 8-cm-long catheter scissored from a 14-F Foley catheter and was inserted into the uterus to prevent cervical or vaginal stenosis. The upper end of the graft was applied onto the lower uterine segment with delayed absorbable sutures. The lower end was sutured to the high vaginal or vestibular mucosa. MAIN OUTCOME MEASURE(S): The feasibility and effect of combination single port laparoscopic with vaginal cervicovaginal reconstruction in the congenital atresia of cervix. RESULT(S): The operation was successful. The operating time was 90 minutes. Hospitalization was 3 days. There were no intraoperative and postoperative complications. The patient had resumption of menses at three cycles postoperatively, and she had no dysmenorrhea. No cervical or vaginal stenosis occurred because of the Foley catheter. CONCLUSION(S): Single port laparoscopic combined with vaginal cervicovaginal reconstruction provided a minimally invasive, safe, and effective surgical option for the young patient with congenital atresia of cervix. It was successful and without complications or cervical or vaginal stenosis.

[Outcomes of implanting porcine small intestinal submucosa mesh in rabbit vesicovaginal space].

Objective: To assess surgical outcomes of implanted porcine small intestinal submucosa (SIS) mesh in the rabbit vesicovaginal space (VVS) and explore its application value in pelvic floor reconstruction surgery. Methods: Sixteen male rabbits were randomly divided into four groups, and each group had four rabbits. All groups of rabbits were implanted with SIS mesh in the vesicovaginal space. They were humanely killed after a postoperative period of 7, 30, 90 and 180 days by group. The grafted area was removed with the surrounding bladder and vaginal tissues. The specimens were embedded in paraffin and then stained with HE and Masson's trichrome stains for visual observations, cells counts, and assessment of tissues and collagen fibers. Results: (1) After HE staining, a large number of inflammatory response cells mainly eosinophils and lymphocytes infiltrated around the SIS mesh in 7 days group, and neovascularization was observed, the infiltration area of inflammatory response cells further increased in 30 days group, the infiltration area of inflammatory response cells significantly reduced in 90 days group, while the inflammatory response basically subsided in 180 days group. (2) After Masson's trichromestaining, the collagen structure of SIS mesh in 7 days group was clear and intact. While, the collagen structure of SIS mesh was partially degraded in 30 days group, the SIS meshes of 4 rabbits were completely degraded, but the collagen fragments of SIS remained in 90 days group. In 180 days group, the SIS mesh of all rabbits was degraded, and one of them had the formation of new collagen fibers. Conclusions: SIS mesh implanted into the VVS of rabbits can lead to a transient non infective inflammatory reaction, which could be completely degraded and a small amount of new collagen fibers could be produced after 180 days of implantation. Which shown that SIS mesh should be used cautiously in pelvic floor reconstruction surgery.

Failure of decellularized porcine small intestinal submucosa as a heart valved conduit.

OBJECTIVE: Decellularized extracellular matrix made from porcine small intestinal submucosa, commercially available as CorMatrix (CorMatrix Cardiovascular, Inc, Roswell, Ga) is used off-label to reconstruct heart valves. Recently, surgeons experienced failures and words of caution were raised. The aim of this study was to evaluate decellularized porcine small intestinal submucosa as right-sided heart valved conduit in a xenogeneic animal model. METHODS: A pulmonary valve replacement was performed with custom-made valved conduits in 10 lambs and 10 sheep (1 month [3 lambs and 3 sheep], 3 months [3 lambs and 3 sheep], 6 months [4 lambs and 4 sheep]). Valve function was assessed after implantation and before the animal was put to death. Explanted conduits were inspected macroscopically and analyzed using immunohistochemistry and scanning electron microscopy. They also underwent mechanical testing and testing for biochemical composition. RESULTS: All valved conduits were successfully implanted. Five sheep and 2 lambs died due to congestive heart failure within 2 months after surgery. In the animals that died, the valve leaflets were thickened with signs of inflammation (endocarditis in 4). Five sheep and 8 lambs (1 month: 6 out of 6 animals, 3 months: 4 out of 6 animals, 6 months: 3 out of 8 animals) survived planned follow-up. At the time they were put to death, 5 lambs had significant pulmonary stenosis and 1 sheep showed severe regurgitation. A well-functioning valve was seen in 4 sheep and 3 lambs for up to 3 months. These leaflets showed limited signs of remodeling. CONCLUSIONS: Fifty percent of sheep and 20% of lambs died due to valve failure before the planned follow-up period was complete. A well-functioning valve was seen in 35% of animals, albeit with limited signs of tissue remodeling at ≤3 months after implantation. Further analysis is needed to understand the disturbing dichotomous outcome before clinical application can be advised.

Inferior Meatus Augmentation Procedure (IMAP) to Treat Empty Nose Syndrome: A Pilot Study.

Our understanding of empty nose syndrome (ENS) continues to evolve. Prior studies evaluating airway augmentation to treat ENS did not use validated disease-specific questionnaires, making the true impact of these surgeries unclear. We present a case series of 10 patients with ENS (11 procedures) who underwent the inferior meatus augmentation procedure (IMAP) between September 2014 and May 2017. Subjective outcomes of IMAP included comparisons of preoperative and postoperative assessments (1 week, 1 month, 3 months, 6 months) using the Empty Nose Syndrome 6-item Questionnaire (ENS6Q), Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder 7-item Scale (GAD-7), and Sino-Nasal Outcome Test-22 (SNOT-22). The decrement in ENS6Q scores observed maintained statistical significance at 6 months (P ≤ .001). Similar results were achieved with PHQ-9, GAD-7, and SNOT-22 (P ≤ .01, P ≤ .01, P ≤ .001, respectively). IMAP can dramatically improve the quality of life of ENS patients regarding both ENS-specific symptoms and psychological well-being.

Use of four-layer porcine small intestinal submucosa alone as a scaffold for the treatment of deep corneal defects in dogs and cats: preliminary results.

BACKGROUND: To describe the efficacy of four-layer porcine small intestinal submucosa (Vetrix BioSIS plus+) as single scaffold for the treatment of deep corneal lesions in dogs and cats. METHODS: 10 dogs and 3 cats with deep or full thickness corneal defects were treated surgically with BioSIS plus graft. Corneal transparency scores and vision were evaluated. RESULTS: Lesions in dogs were four perforations, three descemetoceles, two limbal melanocytomas and one deep corneal ulcer. In cats, there were one limbal melanocytoma and two perforations. The average length of the follow-up was 86 days. In all, 12 out of 13 eyes treated were visual at last recheck (92.3 per cent). The scars were mild eight cases (66.7 per cent), but denser in four cases (33.4 per cent). Complication were partial collagenolysis in three cases (25 per cent), which resolved with medical therapy, mild corneal pigmentation in one case (8.4 per cent) and anterior synechia in one case (8.4 per cent). One case experienced severe collagenolysis and was enucleated 21 days postoperatively. CONCLUSIONS: Four-layer porcine SIS graft was successfully used for surgical treatment of deep corneal lesions in selected corneal diseases in a small series of dogs and cats, with good results in terms of mechanic support and corneal transparency.

Entire mitral reconstruction with porcine extracellular matrix in an acute porcine model.

OBJECTIVE: The objective of our study was to investigate the feasibility of reconstructing the entire mitral valvular and subvalvular apparatus in pigs using a modified tube graft design made of 2-ply small intestinal submucosa extracellular matrix. METHODS: The reconstructions were performed in an acute 80-kg porcine model with 8 pigs, each acting as its own control. A modified tube graft was designed from a sheet of 2-ply small intestinal submucosa extracellular matrix. Before and after mitral valve reconstruction, echocardiography was used to assess mitral regurgitation, left ventricular outflow tract obstruction due to systolic anterior motion, mitral stenosis, leaflet mobility, and leaflet geometry. RESULTS: The reconstructed mitral valves were fully functional without any observable echocardiographic signs of regurgitation. We did not observe any left ventricular outflow tract obstruction due to systolic anterior motion nor any mitral valve stenosis, despite a diminished septal-lateral distance after reconstruction. The reconstruction had a reduced tenting area, a reduced coaptation length (9.6 ± 1.7 mm vs 7.9 ± 1.0 mm, P = .010, diff = -1.7 mm, 95% confidence interval, -3.1 to -0.4 mm), and atrial bending of both leaflets. CONCLUSIONS: In this acute porcine study, entire mitral valvular and subvalvular apparatus reconstruction using a modified tube graft design made from 2-ply small intestinal submucosal extracellular matrix was feasible. The 2-ply small intestinal submucosa extracellular matrix could withstand the pressure exerted by the left ventricle without any signs of tearing or rupture. These promising results warrant further assessment of both the annular geometry and the long-term durability.

Long-term follow-up of neurogenic bladder patients after bladder augmentation with small intestinal submucosa.

PURPOSE: To evaluate the long-term effect of using small intestinal submucosa (SIS) for bladder augmentation in patients with neurogenic bladder. MATERIALS AND METHODS: A total of 15 patients (age range 14-65 years; mean age 29.6 years) were enrolled in our study. The patients had poor bladder capacity and compliance caused by a neurogenic disorder requiring bladder augmentation. A small intestinal submucosa (SIS) cystoplasty was performed alone or in combination with ureter reimplantation. We prospectively followed the cohort to assess the urodynamics parameters, morphologic changes and patient satisfaction and evaluate the clinical benefit of the SIS procedure in long term. The surgical indications and complications were analyzed. RESULTS: The duration of follow-up ranged from 4.5 to 8.3 years (mean 6.3 years). Nine patients had expected long-term benefit, leading to an overall success rate of 60%. Two patients experienced immediate failure, and four patients slowed decrease in bladder capacity over time. Compared with the baseline data, there were significant increases in bladder capacity (163.5 ± 80.90-275.6 ± 159.5 ml, p < 0.05) and a significant decrease in maximum detrusor pressure (45.07 ± 29.03-17.60 ± 10.34 cmH2O, p < 0.05). Histologic examinations showed a complete conversion of SIS, leaving the urothelial lining and bladder wall containing muscular, vascular, and relatively thick connective tissue. Major complications included vesicoureteral reflux in five patients, bladder stone formation in one patient, and bladder perforation in one patient. CONCLUSION: Bladder augmentation with an SIS graft offers a partial long-term success rate in neurogenic bladder patients. This procedure cannot be recommended as a substitute for enterocystoplasty, especially in patients with severe upper urinary tract deterioration and/or bladder fibrosis.

Comparison of neovaginoplasty using acellular porcine small intestinal submucosa graft or Interceed in patients with Mayer-Rokitansky-Küster-Hauser syndrome.

OBJECTIVE: To compare using the acellular porcine small intestinal submucosa (SIS) graft or the Interceed in patients with MRKH syndrome undergoing creation of a neovagina. METHODS: In this retrospective study, patients with MRKH syndrome undergoing creation of a neovagina from 2016 to 2018 were retrospectively investigated. Wharton-Sheares-George neovaginoplasty was performed using the acellular porcine SIS graft or the Interceed. RESULTS: Overall, 67 patients were included for analysis. The operating time, the estimated blood loss and return of bowel activity were similar between the two groups. However, the total cost in the SIS group was significantly higher than that in the Interceed group due to the cost of the SIS graft. The mean length and width of the neovagina were similar between the two groups. However, the incidence of granulation in vaginal apex was higher in the SIS graft group than that in the Interceed group. There was no statistically significant difference in the total FSFI scores between the two groups who became sexually active postoperatively. CONCLUSIONS: Our results demonstrated that Wharton-Sheares-George method provided the patients to have satisfactory sexual intercourse. The Interceed played a role in the reconstruction of neovagina no less than the SIS graft.

Electrospun P(LLA-CL) Nanoscale Fibrinogen Patch vs Porcine Small Intestine Submucosa Graft Repair of Inguinal Hernia in Adults: A Randomized, Single-Blind, Controlled, Multicenter, Noninferiority Trial.

BACKGROUND: The aim of this study was to compare primary efficacy indicators of a low-cost, electrospun, nanoscale P(LLA-CL)/fibrinogen patch with a porcine small intestine submucosa patch for hernia repair. STUDY DESIGN: A randomized, single-blind, controlled multicenter trial was performed in 3 hospitals in Shanghai. Eligible patients (20 to 75 years old) with primary unilateral, reducible groin hernias were randomly assigned (1:1) to electrospun nanoscale P(LLA-CL)/fibrinogen patch (experimental group) or porcine small intestine submucosa (control group) patch groups. Patients were treated with the Lichtenstein technique, and the primary endpoint was hernia recurrence at 33 months after surgery. The secondary endpoints were postoperative complications including groin pain and operative site infections. RESULTS: Between July 2014 and February 2016, 172 patients were assigned to experimental (n = 86) and control (n = 86) groups. At 6-month follow-up, postoperative complications occurred in 5 patients (5 of 86, 5.81%) and 2 (2 of 86, 2.35%) patients in the control and experimental groups, respectively (p < 0.05). At 33-month follow-up, recurrence was observed in 2 patients (2 of 79, 2.53%) in the control group vs none in the experimental group (0 of 78) (the 95% CI difference between the experimental and control groups was -0.93% to 6.00% and within the preset noninferior margin of Δ10%). No significant differences were found in the degree of chronic pain and complications 33 months after surgery between the 2 groups. CONCLUSIONS: Because the recurrence rates and postoperative complications after 33 months were not inferior in the experimental group, we believe that the P(LLA-CL)/fibrinogen patch, as a low cost alternative, has prospects for widespread clinical use.

The bolster technique utilising small intestinal submucosa wound matrix: A novel approach to wound treatment.

Managing acute wounds with soft tissue loss can be very challenging for both patients and physicians. Successful wound healing depends on several factors including exudate control, prevention of infection, and moisture balance. In this case series, we describe a novel combination treatment method utilising small intestinal submucosa wound matrix (SISWM) with the bolster technique as a way of assisting the integration of collagen-based wound treatment products into the base of complex wounds with the intent of restoring a dysfunctional extracellular matrix. In case 1, a 44-year-old female presented with an acute wound resulting from a spider bite to the posterior aspect of the right knee. In case 2, a 12-year-old male sustained multiple injuries to his right foot from an all-terrain vehicle accident. In case 3, an 80-year-old female on anticoagulants sustained an avulsion injury to her left lower leg. In case 4, a 41-year-old female sustained a severe complex avulsion injury to the dorsal left forearm sustained from a dog bite. All patients were successfully treated with SISWM and the bolster technique, and their wounds healed completely within 6 weeks. The bolster technique, when combined with an SISWM, is a novel method designed to enable the SISWM to impart its wound healing properties to these complex traumatic wounds. This case series presents treating clinicians with a different treatment methodology to assist the patient in achieving a successful outcome.

Use of small intestinal submucosa for corporal body grafting in cases of epispadias and epispadias/exstrophy complex.

BACKGROUND: Male epispadias is a rare congenital urogenital anomaly in which the meatus is ectopically located along the dorsal midline of the penile shaft. In cases associated with severe curvature, functional and cosmetic outcomes could be accomplished by lengthening the shorter dorsal surface with the use of corporal grafting. Various graft materials have been used in the past for hypospadias repair including tunica vaginalis, dermis, and small intestinal submucosa (SIS). The use of SIS grafting for corporoplasty during epispadias repair has rarely been described in the literature. OBJECTIVE: To report the experience in the management of dorsal corporal body grafting using SIS in children with severe penile curvature due to epispadias. STUDY DESIGN: The authors retrospectively reviewed the charts of all patients with epispadias or bladder exstrophy/epispadias complex and severe dorsal chordee (>40°) who underwent epispadias repair with single-layer SIS for corporal body grafting. Clinical variables, surgical technique, and outcomes were analyzed. RESULTS: A total of nine consecutive patients underwent staged epispadias repair with dorsal corporal single-layer SIS grafting (summary figure). Of these, four (44.4%) had primary penopubic epispadias, one (11.1%) had mid-shaft epispadias, and four (44.4%) had bladder exstrophy/epispadias complex. The mean age at surgery was 13.4 ± 6 months. After phalloplasty with SIS grafting, there were no reported complications related to the graft during the post-operative period or follow-up visits. DISCUSSION: Although traditional techniques for epispadias repair allow some degree of corporal lengthening, they also result in abrupt medial rotation of the corporal bodies leading to torqueing and potential unsatisfactory cosmetic results. In contrast, the authors use single-layer SIS for corporal body grafting, and this study technique results in a more gradual inward rotation thus allowing more anatomical accuracy. Furthermore, an advantage of the use of SIS over other grafting materials is that there is no need to harvest an autologous graft such as tunica vaginalis or dermis. CONCLUSION: Epispadias repair using single-layer SIS corporal body grafting is an effective, safe, and feasible method, which provides satisfactory cosmesis and correction of dorsal curvature in congenital epispadias in children. Furthermore, a more normal penis appearance, without a decrease in the corporal length or diameter, is achieved with this technique.

Robotic transanal minimally invasive rectal mucosa harvest.

INTRODUCTION: Buccal mucosal grafts (BMG) are traditionally used in urethral reconstruction. There may be insufficient BMG for applications requiring large grafts, such as urethral stricture after gender-affirming phalloplasty. Rectal mucosa in lieu of BMG avoids oral impairment, while potentially affording less postoperative pain and larger graft dimensions. Transanal minimally invasive surgery (TAMIS) using laparoscopic instruments has been described. Due to technical challenges of harvesting a sizable graft within the rectal lumen, we adopted a new robotic approach. We demonstrate the feasibility and safety of a novel technique of Robotic TAMIS (R-TAMIS) in the harvest of rectal mucosa for the purpose of onlay graft urethroplasty. METHODS: Six patients (ages 28-60) presenting with urethral stricture and one vaginal stricture underwent robotic rectal mucosal harvest. The procedure, which was first studied on an inanimate bovine colon model, was performed under general anesthesia in lithotomy position using the GelPOINTTM Path Transanal Access. Mucosa was harvested robotically after submucosal hydrodissection. Graft size harvested correlated with surface area needed for urethral or vaginal reconstruction. Following specimen retrieval, flexible sigmoidoscopy confirmed hemostasis. The graft was placed as an onlay for urethroplasty. RESULTS: There were no intraoperative or postoperative complications. Mean graft size was 11.4 × 3.0 cm. All reconstructions had excellent graft take. All patients recovered without morbidity or mortality. They reported minimal postoperative pain and all regained bowel function on postoperative day one. Patients with prior BMG harvests subjectively self-reported less postoperative pain and greater quality of life. There have been no long-term complications at a median follow-up of 17 months. CONCLUSIONS: To our knowledge, this is the first use of R-TAMIS for rectal mucosa harvest. Our preliminary series indicates this approach is feasible and safe, constituting a promising minimally invasive technique for urethral reconstruction. Prospective studies evaluating graft outcomes and donor site morbidity with more long-term follow-up are needed.