Graft Ureter Research Articles

Surgical complications in live‐donor pediatric and adolescent renal transplantation: Study of risk factors

To report the surgical complications among our pediatric and adolescent renal transplants and to analyze the different factors that may influence the occurrence of such complications. A total of 250 pediatric and adolescent renal transplants were included in this study. Of these patients, there were 154 boys and 96 girls with a mean age of 15.4+/-3.7 yr (range 5-20 yr). All patients received their kidneys from living donors. Four patients underwent renal retransplantation. Surgical complications were reported and their incidence was correlated with several pretransplant, technical and post-transplant risk factors by both univariate and multivariate analyses. The impact of surgical complications on graft and patient survival was computed using the Kaplan-Meier technique. Among the 250 patients, 35 surgical complications were encountered in 33 patients. These complications included urinary leakage in 10 patients, ureteric stricture in 11 patients, complicated lymphocele in eight patients, hematoma necessitating surgical exploration in two patients, wound dehiscence in one patient, stone of the graft ureter in one patient and renal artery stenosis in two patients. The incidence of urological complications (ureteral stenosis, urinary leakage and stone disease) was 8.8% and vascular complications 0.8%. Small ureteric leakage (four patients) was treated by endourologic techniques, whereas leaks associated with ureteral necrosis required open revision. Endourologic treatment was attempted in early and mild cases of ureteric obstruction. In late and severe cases, surgery was performed. On univariate analysis, the factors that significantly affected the incidence of surgical complications were recipient's age, lower urinary tract abnormalities, the type of primary urinary recontinuity, the time to diuresis, and height and weight of the patients. On multivariate analysis, the type of primary urinary continuity was the only factor that sustained statistical significance. Neither patient nor graft survival was affected by the occurrence of surgical complications. Primary urinary continuity is the only risk factor that affects the incidence of surgical complications among pediatric and adolescent live donor renal transplants, with the extravesical technique of Lich-Gregoir providing the best results. Surgical complications in pediatric and adolescent renal transplantation can be minimized if basic principles of careful transplant techniques are used. Prompt identification and treatment of any complication is paramount to graft and patient survival.

SURGICAL COMPLICATIONS IN LIVE-DONOR PEDIATRIC RENAL TRANSPLANTATION: STUDY OF RISK FACTORS

P690 Aims: To report the surgical complications among our pediatric renal transplants and to analyze the different factors that may influence the occurrence of such complications. Methods: A total, 250 pediatric renal transplants were included into this study. Of these children there were 154 boys and 96 girls with a mean age of 15.4 ± 3.7 years (range 5 to 20). All patients received their kidneys from living donors. Four patients underwent repeat renal transplantation. Surgical complications were reported and their incidence was correlated with several pre-transplant, technical and post-transplant risk factors by both univariate and multivariate analyses. The impact of surgical complications on graft and patient survival was computed using the Kaplan-Meier technique. Results: Among the 250 patients, 35 surgical complications were encountered in 33 patients. These complications included urinary leakage in 10 patients, ureteric stricture in 11, complicated lymphocele in 8, hematoma necessitating surgical exploration in 2, wound dehiscence in 1, stone of the graft ureter in 1 and renal artery stenosis in 2. The incidence of urological complications (ureteral stenosis, urinary leakage and stone disease) was 8.8% and vascular complications 0.8%. Small ureteric leakage (4 patients) was treated by endourologic techniques, whereas leaks associated with ureteral necrosis required open revision. Endourologic treatment was tried in early and mild cases of ureteric obstruction. In late and severe cases, surgery was performed. On univariate analysis the factors that significantly affected the incidence of surgical complications were recipient’s age, lower urinary tract abnormalities, the type of primary urinary recontinuity, the time to diuresis, height and weight of the patients. On multivariate analysis, the type of primary urinary continuity was the only factor that sustained statistical significance. Neither patient nor graft survival was affected by the occurrence of surgical complications. Conclusions: Primary urinary continuity is the only risk factor that affects the incidence of surgical complications among live-donor kidney pediatric renal transplants, with the extravesical technique of Lich-Gregoir giving the best results. Surgical complications in pediatric renal transplantation can be minimized if basic principles of careful transplant technique are used. Prompt identification and treatment of any complication are paramount to graft and patient survival.

Ureteral replacement using porcine small intestine submucosa in a porcine model

Objectives To investigate an alternative technique using an onlay patch of porcine small intestine submucosa (SIS) allograft to bridge a ureteral defect. For ureteral strictures that fail endourologic management, few options are available for minimally invasive repair or reconstruction. Although laparoscopic interposition of a tubularized allograft of porcine SIS has great promise, animal studies have yielded mixed results. Methods In 9 anesthetized female pigs, cystoscopy and retrograde pyelography were performed, and a ureteral stent was placed. Transperitoneal laparoscopic access was obtained, and a segment of ureter 2 cm long and encompassing one half the ureteral circumference was excised. An oval-shaped patch of SIS was sutured to the native ureter to cover the defect. In one control survival animal, the ureter was excised and a stent placed, but no SIS onlay was performed. Two pigs were killed immediately. In the survival group (6 pigs), the stents were removed at 1 week (n = 2), 2 weeks (n = 2), or 4 weeks (n = 2) and the corresponding animals were killed at 3 weeks (n = 2), 6 weeks (n = 2), and 9 weeks (n = 2). Intravenous urography was performed to evaluate renal function, and retrograde pyelography was performed after harvest to identify ureteral stricture or obstruction. The ureteral grafts were measured and examined histologically. Results All 6 kidneys from the survival group were grossly normal, appeared promptly on intravenous urography, and were patent on retrograde pyelography. The control animal demonstrated complete ureteral obstruction. By 9 weeks, the SIS graft was replaced with ureteral tissue, including the muscle layers. The epithelium was primarily transitional epithelium, with focal intestinal metaplasia. The submucosa and ureteral musculature appeared histologically normal. Conclusions In the porcine model, a patch graft technique using SIS appears to induce ureteral regrowth. Renal function remained intact, and no evidence of stricture was demonstrated on radiographic imaging. Before clinical application of this technique, evaluation in a stricture model is required.

Ureteral Segment Replacement Using a Circumferential Small-Intestinal Submucosa Xenogenic Graft

ABSTRACT We wished to determine whether small-intestinal submucosa (SIS) will epithelialize when used as a ureteral replacement material. An 11-mm segment of native ureter was excised from eight New Zealand White rabbits and replaced with an 11-mm porcine SIS graft, which was circumferentially wrapped around a ureteral stent. The SIS ureteral grafts were harvested at 11 days or 35 days postimplantation and examined grossly and by standard light microscopy techniques. Partial epithelialization with the ingrowth of urothelium, smooth muscle cells, and blood vessels was observed in the grafts harvested at 11 days postimplantation. The SIS ureteral grafts examined at 35 days postimplantation showed additional restructuring of the smooth muscle cell layer and more organized epithelialization in comparison to the SIS graft examined at 11 days. After 35 days of regenerative healing, elements of all three layers of the native ureter were observed within the collagen matrix of the SIS graft. No significant complications were observed, but all subjects (8/8) demonstrated mild intra-abdominal adhesions. Mild collecting system dilatations were observed in 4/4 (100%) of the animals harvested at 35 days and in 0/4 (0%) of the animals harvested at 11 days. We have this demonstrated in this preliminary study that SIS xenografts will epithelialize when used as a ureteral replacement material. The repair mechanism of these ureteral grafts occurred through a regenerative healing process rather than by scar formation. With further studies, this material may prove to be a useful treatment option in patients with ureteral injuries.

Modified Human Ureter and Human Saphenous Vein Grafts Tanned with a Polyepoxy Compound or Glutaraldehyde for Small-Diameter Arterial Substitution

The polyepoxy compound is a new cross-linking agent that is now replacing glutaraldehyde, and human ureter is a new potential substitute for small-caliber arterial prostheses. The present study was performed to compare the use of human ureter grafts tanned with a polyepoxy compound, human ureter grafts tanned with glutaraldehyde, and human saphenous vein grafts tanned with a polyepoxy compound for small-diameter arterial substitutions. Human ureter grafts tanned with a polyepoxy compound (n= eight), human ureter grafts tanned with glutaraldehyde (n=six), and human saphenous vein grafts tanned with a polyepoxy compound (n=eight) were implanted in the carotid arteries of Japanese white rabbits. These grafts were sacrificed after either 1 month's or 6 months' observation. There was no evidence of rejection, aneurysmal formation, and/or infection. Human ureter gcafts tanned with a polyepoxy compound after 1 month's observation (n=six) showed excellent patency without stenosis at the anastomotic sites as well as function, and the histologic findings revealed monolayer endothelial-like cells covering the surface of the graft. Human ureter grafts tanned with glutaraldehyde after 1 month's observation (n=six) were completely occluded with severe intimal hyperplasia. Human saphenous vein grafts tanned with a polyepoxy compound after 1 month's observation (n= six) were patent at the time of explantation, but moderate stenosis caused by intimal hyperplasia at the anastomotic sites was observed. The preliminary data also suggest that, with longer observation of up to 6 months, human ureter grafts tanned with a polyepoxy compound (n=two) showed excellent patency. However, a longer observation of up to 6 months for human saphenous vein grafts tanned with a polyepoxy compound (n=two) revealed severe intimal hyperplasia with intramural thrombosis and/or severe calcification. This study suggests that human ureter grafts tanned with a polyepoxy compound could serve as more satisfactory bioprostheses for the reconstruction of smallcaliber vessels than human ureter grafts tanned with glutaraldehyde or human saphenous vein grafts tanned with a polyepoxy compound.

A modified human ureter graft tanned by a new crosslinking agent polyepoxy compound for small diameter arterial substitutions: an experimental preliminary study.

The effectiveness of human ureter grafts tanned by polyepoxy compound for small diameter arterial substitution was examined in 8 carotid arteries of rabbits, followed by an observation period of either 1 month (n = 6) or 6 months (n = 2). In this model there was no evidence of rejection, aneurysm formation, or infection. The modified human ureter showed excellent patency in all cases as well as excellent function, and the histological evaluation revealed monolayer endothelial-like cells covering all of the surface of the graft as was expected. No intimal hyperplasia was demonstrated at either anastomotic site. This study suggests that our newly designed polyepoxy compound fixed human ureter could serve as a satisfactory blood conduit with good long-term patency for substitution.

A simplified technique for ureteroneocystostomy in renal transplantation

From October 1988 to December 1993, 148 kidney transplants were carried out at our institution. An extravesical ureteral reimplantation technique resulting in a submucosal tunnel in the bladder wall was performed on 101 of the patients. For this technique, two small incisions are made at the outer part of the bladder wall until the mucosa is seen, then a submucosal tunnel is dissected between them and the graft's ureter is introduced and advanced in it (Alférez-Barry). Afterward the bladder mucosa is opened at the distal incision and the ureter is introduced into the bladder and fixed by a single direct anchorage stich (Taguchi). The minimal patients' follow-up is 18 months. Complications deriving from ureter reimplantation with this technique were present in 12.8% of the patients and included 4 cases of stenosis (3.9%), 4 cases of urinary fistula (3.9%), and 5 cases of hematuria (4.9%). We conclude that submucosal tunnelled ureteroneocystostomy with direct anchorage is a technique that simplifies kidney transplant surgery with good results. Ureteral direct anchorage can be used in any kind of ureteral anastomosis.

Ureteral graft in urological reconstruction: Clinical experience and review of the literature: S.G. Docimo, J.P. Gearhart, and R.D. Jeffs. J Urol 153:1648–1650, (May), 1995

Ureteral graft in urological reconstruction: Clinical experience and review of the literature: S.G. Docimo, J.P. Gearhart, and R.D. Jeffs. J Urol 153:1648–1650, (May), 1995

Ureteral Graft in Urological Reconstruction: Clinical Experience and Review of the Literature

We report 7 cases in which grafts of ureter were used as tube and patch segments in urethral reconstruction and formation of a continent catheterizable stoma. The ureteral grafts survived without long-term stricture in all cases. Meticulous preparation of the graft and recipient bed is required for success, as previously demonstrated experimentally. When available, ureter is an excellent source of tissue for urological reconstruction.

Ureteral Graft in Urological Reconstruction

Ureteral Graft in Urological Reconstruction

Performance of a New Vascular Xeno Prosthesis

To date no prosthetic vascular prosthesis performs as well as the autologous saphenous vein in diameters of 6 mm and less. The purpose of this study was to compare the in vitro and in vivo performance of a new glutaraldehyde stabilized, narrow diameter (4 mm), vascular prosthesis fashioned from bovine ureters (Flonova®) with the saphenous vein and polytetrafluoroethylene (PTFE) prostheses. The methods used for the comparative in vitro analysis of the bovine ureter and saphenous vein were modifications of tests recommended by the American National Standards for Vascular Prostheses. Blood compatibility was evaluated by measuring platelet consumption in an artificial circulation, and heparin uptake was quantified using tritiated heparin. The results indicate that the bovine ureter grafts have an adequate degree of mural integrity and hemocompatible properties comparable to saphenous vein. The in vivo patency in a canine bilateral femoral interposition model was 62.5% (10/16) for the bovine ureters and 43.75% (7/16) for PTFE. Bovine ureter grafts appear to have an excellent potential for use in narrow diameter peripheral and coronary arterial bypass procedures and warrant further investigation.

Kidney transplantation in patients with a urinary diversion

Patients with congenital abnormalities of the lower urinary tract may develop end-stage renal failure, necessitating kidney transplantation. If their own bladder is unsuitable for implantation of the graft ureter, or if reconstructive surgery of the lower tract is not possible, the ureter can be implanted in an ileostomy or colostomy. The results of a follow-up study of 22 kidney transplants in 19 patients with a urinary diversion are reported. The immediate post-operative surgical complications were few, including one superficial wound abscess, one lymphocele, and one hematoma. One patient had a perforation of the ileal loop after the excision of an infected kidney. The late surgical complications involved excessive length of the ileal loop in two patients, nephrolithiasis in two, and ureteroileal anastomotic strictures in three. One patient died of liver failure 2 years posttransplantation with a well-functioning graft. Today, 16 of the remaining 18 patients have a well-functioning graft, one has impaired kidney function, and one is on dialysis. The 1- and 2-year graft survival rates are 90.6% and 74.7%, respectively, and the mean follow-up period is 5.5 years. Our results show that kidney transplantation in patients with a urinary diversion can be carried out with an acceptable complication rate and a very good patient and graft survival rate.

Modified Ureter GraftとGore-tex Graftとの細動脈移植における長期移植成績の比較検討

Modified Ureter GraftとGore-tex Graftとの細動脈移植における長期移植成績の比較検討

Gamma-camera scintigraphy in the diagnosis of graft ureter obstruction after renal allograft transplantation

Gamma-camera scintigraphy studies in five patients with graft ureter obstruction are presented. The isotope used was 131I-hippuranR. The diagnosis was suspected when an accumulation of activity in the pelvic region was seen, and it was in all five patients confirmed at surgery or intravenous urography.

Direct cell mediated lympholysis. A test of allograft-rejection in human kidney recipients.

In kidney transplanted patients a clear coincidence was observed between clinical signs of allograft rejection and the presence in the peripheral blood of killer cells able to lyse either PHA lymphoblasts from the actual donor or selected unrelated individuals. In recipients with non-immunological complications such as leakage on the graft ureter or primary anuria caused by renal ischaemia, no cellular cytotoxicity against specific or selected target cells was observed. The specificity of this Cell Mediated Lympholysis in two of the cases reported could not be explained by the serologically detectable HL-A antigens, indicating the existence of other determinants of importance for the killing capability of in vivo produced effector cells.

Homologous ureter grafts. Experimental studies.

Artificial ureter defects in dogs were replaced by homologous ureter grafts. Twenty-four experiments were carried out. The grafts without being necrotized underwent a certain reconstruction. Good functional and anatomical results were obtained in 11 cases. Fibrosis in the walls resulted in a slight reduction of the lumen and a shrinkage of the graft without any significant interference with the function of the ureter. These results indicate that the homologous graft is of value in experimental replacement of defects in the urether.

Experimental bridging of ureteral defects by free ureteral grafts: A study in dogs : R. S. Sethi, Amarjit Singh, and Waryam Singh. Ind. J. Surg. 32:358–364 (July), 1970

Experimental bridging of ureteral defects by free ureteral grafts: A study in dogs : R. S. Sethi, Amarjit Singh, and Waryam Singh. Ind. J. Surg. 32:358–364 (July), 1970

Failure of Freeze-Dried Homologous Arteries Used as Ureteral Grafts

No AccessJournal of Urology1 Nov 1955Failure of Freeze-Dried Homologous Arteries Used as Ureteral Grafts William H. SewellLt, MC, USNR William H. SewellWilliam H. Sewell Present address: Albany Hospital, Albany, N. Y. More articles by this author View All Author Informationhttps://doi.org/10.1016/S0022-5347(17)67325-7AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail © 1955 by The American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetailsCited byGreenberg R, Coleman J, Quiguyan C, Marion D, Albanese C, O’Dell G and Mcgovern J (2018) Bladder Mucosal Grafts: Experimental Use as a Ureteral Substitute and Observation of Certain Physical PropertiesJournal of Urology, VOL. 129, NO. 3, (634-636), Online publication date: 1-Mar-1983.Habib H, Charuworn T, Primeau J, Mark D and Thompson I (2018) Repair of Ureteral Defects Using Uninterrupted Non-penetrated Bowel WallJournal of Urology, VOL. 100, NO. 3, (270-279), Online publication date: 1-Sep-1968.Lewis H, Sherwood N and Pierce J (2018) Experimental and Clinical Use of a Ureteral ProsthesisJournal of Urology, VOL. 95, NO. 5, (700-705), Online publication date: 1-May-1966.Kočvara S and Žák F (2018) Ureteral Substitution with Dacron and Teflon ProsthesesJournal of Urology, VOL. 88, NO. 3, (365-376), Online publication date: 1-Sep-1962.Harvard B, Camilleri J, Nadig P and Glenn J (2018) Experimental Transplantation of Freeze-Dried Homologous and Autologous Ureteral SegmentsJournal of Urology, VOL. 86, NO. 4, (385-389), Online publication date: 1-Oct-1961.Hardy Ulm A and Krauss L (2018) Total Unilateral Teflon Ureteral Substitutes in the DogJournal of Urology, VOL. 83, NO. 5, (575-582), Online publication date: 1-May-1960. Volume 74Issue 5November 1955Page: 600-602 Advertisement Copyright & Permissions© 1955 by The American Urological Association Education and Research, Inc.MetricsAuthor Information William H. Sewell Present address: Albany Hospital, Albany, N. Y. More articles by this author Expand All Advertisement PDF downloadLoading ...

Experimental Substitution of the Common Bile Duct With an Autologous Ureteral Graft

Experimental Substitution of the Common Bile Duct With an Autologous Ureteral Graft