Comprehensive Evaluation of Ureteral Healing After Electrosurgical Endopyelotomy in a Porcine Model: Original Report and Review of the Literature

No AccessJournal of UrologyINVESTIGATIVE UROLOGY: Review Article1 Feb 2004Comprehensive Evaluation of Ureteral Healing After Electrosurgical Endopyelotomy in a Porcine Model: Original Report and Review of the Literature CASSIO R. ANDREONI, HSUEH-KUNG LIN, EPHREM OLWENY, JAIME LANDMAN, DAVID LEE, DAVID BOSTWICK, and RALPH V. CLAYMAN CASSIO R. ANDREONICASSIO R. ANDREONI Supported by CAPES scholarship. More articles by this author , HSUEH-KUNG LINHSUEH-KUNG LIN More articles by this author , EPHREM OLWENYEPHREM OLWENY More articles by this author , JAIME LANDMANJAIME LANDMAN More articles by this author , DAVID LEEDAVID LEE More articles by this author , DAVID BOSTWICKDAVID BOSTWICK Financial interest and/or other relationship with GlaxoSmithKline, Genotherapeutics, Diagnocure, Photocure, AstraZeneca, Bostwick Laboratories and Medlon. More articles by this author , and RALPH V. CLAYMANRALPH V. CLAYMAN Financial interest and/or other relationship with Applied Medical, Endocare, Greenwald, Inc., Microvasive, Cook Urological and Orthopedic Systems, Inc. More articles by this author View All Author Informationhttps://doi.org/10.1097/01.ju.0000108383.18165.f5AboutFull TextPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract Purpose: Endopyelotomy (EP) has yet to equal the success achieved with open dismembered pyeloplasty. To understand better the ureteral response to EP we performed a timed histopathological evaluation of the porcine ureter after Acucise (Applied Medical, Rancho Santa Margarita, California) EP. Materials and Methods: In 28 domestic pigs bilateral Acucise EPs were performed and bilateral 7Fr stents were placed. The kidneys, ureters and bladder were harvested after EP at 0, 1, 2, 3, 6, 12 and 18 hours, 1, 3 and 5 days, and 1, 2, 4 and 8 weeks. The stents were removed after 4 weeks. The healing area of the ureter was sectioned. Half was fixed in formalin 10%, stained and evaluated by light microscopy. The other half was frozen and reverse transcriptase-polymerase chain reaction was performed to measure steady state levels of epidermal growth factor, transforming growth factor (TGF)-α, TGF-β1, TGF-β2, TGF-β3, keratinocyte growth factor, vascular endothelial growth factor, insulin-like growth factor, platelet derived growth factor, collagen type 1, integrin and fibronectin transcript expression. Immunohistochemistry for actin, desmin and myosin expression was completed. The same studies were applied to the mid portion of the unoperated ureter. Results: Initial sealing of the ureterotomy defect was by blood clot and periureteral fat. Complete healing of the mucosa was observed at 2 weeks in animals without an associated urinoma. However, in no case did the muscle layer bridge the whole circumference of the ureter despite followup out to 8 weeks. In the operated ureter elevated expression of keratinocyte growth factor, vascular endothelial growth factor, TGF-α, TGF-β1, TGF-β3 and integrin was detected 2 hours after the operation and sustained for 7 to 14 days after the procedure. Immunohistochemistry revealed that most presumed myocytes seen in the defect were actually myofibroblasts. Persistent urinoma formation beyond the first few days appeared to slow the healing process. Conclusions: Urothelium regenerated rapidly over an iatrogenic ureteral defect despite the absence of a lamina propria. Muscle cell coverage failed to occur completely at 8 weeks. In the initial 8 weeks of the healing process myofibroblasts appear to be prevalent. A persistent urinoma negatively impacts the healing process. References 1 : Intubated ureterotomy: a new operation for ureteral & ureteropelvic stricture. Surg Gynec & Obstet1943; 76: 513. Google Scholar 2 : Hydronephrosis: standardization of surgical treatment. N Engl J Med1940; 222: 910. 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Google Scholar From the Division of Urology, Federal University (CRA), Sao Paulo, Brazil, Division of Urologic Surgery, Department of Surgery, Washington University School of Medicine (H-KL, EO, JL, DL), St. Louis, Missouri, Bostwick Laboratories (DB), Richmond, Virginia, and Department of Urology, University of California-Irvine (RVC), Irvine, California© 2004 by American Urological Association, Inc.FiguresReferencesRelatedDetailsCited BySoria F, Rioja L, Morcillo E, Martin C, Pamplona M and Sánchez F (2018) New Combined Approach in Metallic Ureteral Stenting to Avoid Urothelial Hyperplasia: Study in Swine ModelJournal of Urology, VOL. 185, NO. 5, (1939-1945), Online publication date: 1-May-2011. (2018) Reply by AuthorsJournal of Urology, VOL. 175, NO. 1, (391-391), Online publication date: 1-Jan-2006. Volume 171Issue 2February 2004Page: 859-869 Advertisement Copyright & Permissions© 2004 by American Urological Association, Inc.Keywordswound healingurologic surgical proceduresureterswineelectrosurgeryMetricsAuthor Information CASSIO R. ANDREONI Supported by CAPES scholarship. More articles by this author HSUEH-KUNG LIN More articles by this author EPHREM OLWENY More articles by this author JAIME LANDMAN More articles by this author DAVID LEE More articles by this author DAVID BOSTWICK Financial interest and/or other relationship with GlaxoSmithKline, Genotherapeutics, Diagnocure, Photocure, AstraZeneca, Bostwick Laboratories and Medlon. More articles by this author RALPH V. CLAYMAN Financial interest and/or other relationship with Applied Medical, Endocare, Greenwald, Inc., Microvasive, Cook Urological and Orthopedic Systems, Inc. More articles by this author Expand All Advertisement PDF DownloadLoading ...