Suture-Free Ureterovesical Anastomosis Using a Microvascular Anastomosis System: Canine Cadaveric Study Judith Bertran, Ldo. Vet, Vincent A. Wavreille, DVM, Kathleen L. Ham, DVM, MS, DACVS, Mary A. McLoughlin, DVM, MS, DACVS, and Christopher A. Adin, DVM The Ohio State University, 601 Vernon L Tharp St, Columbus, Ohio
Corresponding Author Christopher Adin, North Carolina State University, 1060 William Moore Dr., Raleigh, NC 27607. E-mail: [email protected] Submitted September 2014 Accepted January 2015 DOI:10.1111/vsu.12337
Objective: To describe a suture-free ureterovesical anastomosis using a microvascular anastomotic system (MAS) and compare the surgical time and bursting pressure to a sutured ureterovesical anastomosis (SA) with and without an extravesical seromuscular tunnel (EVSMT). Study Design: Randomized, unblocked design, ex vivo study. Animals: Three canine cadavers. Methods: For each cadaver, the ureters were sectioned into 3 equal lengths. The 6 sections were randomly assigned to receive either the MAS or end-side SA. The first cadaver (3 MAS, 3 SA) was used to refine the technique, and the remaining 2 cadavers were used for evaluation. Surgical time and bursting pressure of the anastomosis were compared between MAS and SA (n ¼ 6 per technique). After bursting pressure testing of each anastomosis, an SMT was created over the anastomoses. Bursting pressures were again recorded and compared across techniques. Results: The surgery time was significantly shorter for MAS (median 5.4 minutes) than SA (median 15.8 minutes; P ¼.002). The bursting pressure was significantly higher for MAS (median 189.5 cmH2O) than SA (median 64 cmH2O; P ¼.002). The bursting pressure for MAS-EVSMT (median 398.5 cmH2O) was not significantly different from the SA-EVSMT (median 321 cmH2O, P ¼.567); however, the creation of an SMT significantly increased the bursting pressure for both techniques (P ¼.028, respectively). Conclusion: This study demonstrated the feasibility of a suture-free ureterovesical anastomosis in the canine cadaver using a commercially available MAS. The MAS anastomosis was faster and resulted in higher bursting pressures than SA. The creation of an SMT improved the bursting resistance of both techniques but there was no difference between the techniques covered by an EVSMT.
Ureteral surgery has been described for the treatment of both acquired1–12 and congenital13 conditions in the dog. Primary repair of the ureter using fine suture material is technically demanding, requiring specialized instruments and microsurgical training that are not widely available.13,14 In dogs with distal ureteral obstructions and in those undergoing renal transplantation, direct anastomosis of the ureter to the urinary bladder (ureterovesical anastomosis) is indicated.15–17 While ureterovesical anastomosis is helpful in dealing with luminal disparity that occurs with chronic obstruction, creating a leak-proof anastomosis without luminal narrowing remains technically difficult in dogs with a small ureter.15–17 Surgical techniques for ureterovesical anastomosis are described as intra or extravesicular.16,17 Intravesicular techniques such as the LeadbetterPolitano technique (mucosal apposition) are performed through a cystotomy to access the urinary bladder lumen.17 Extravesicular techniques such as the Lich-Gregoir technique do not required a cystotomy.17,18 Reported complications of ureterovesical
anastomosis include urine leakage, granuloma formation, ureteral obstruction, and chronic hematuria.19 Some surgeons have adopted a modified Lich-Gregoir technique, which allows an extravesical anastomosis that is covered by closure of the mucosal anastomosis in a seromuscular tunnel.17,18 The successful use of a commercially available microanastomotic system (MAS) for ureteral anastomosis in the dog using an ex vivo model was recently reported.20 This device, known as the GEM Microvascular Anastomotic COUPLERTM (GEM, Birmingham, AL), has been used in people for microvascular anastomosis and is recommended for vessels having an outside diameter >0.8 and
Corresponding Author Christopher Adin, North Carolina State University, 1060 William Moore Dr., Raleigh, NC 27607. E-mail: [email protected] Submitted September 2014 Accepted January 2015 DOI:10.1111/vsu.12337
Objective: To describe a suture-free ureterovesical anastomosis using a microvascular anastomotic system (MAS) and compare the surgical time and bursting pressure to a sutured ureterovesical anastomosis (SA) with and without an extravesical seromuscular tunnel (EVSMT). Study Design: Randomized, unblocked design, ex vivo study. Animals: Three canine cadavers. Methods: For each cadaver, the ureters were sectioned into 3 equal lengths. The 6 sections were randomly assigned to receive either the MAS or end-side SA. The first cadaver (3 MAS, 3 SA) was used to refine the technique, and the remaining 2 cadavers were used for evaluation. Surgical time and bursting pressure of the anastomosis were compared between MAS and SA (n ¼ 6 per technique). After bursting pressure testing of each anastomosis, an SMT was created over the anastomoses. Bursting pressures were again recorded and compared across techniques. Results: The surgery time was significantly shorter for MAS (median 5.4 minutes) than SA (median 15.8 minutes; P ¼.002). The bursting pressure was significantly higher for MAS (median 189.5 cmH2O) than SA (median 64 cmH2O; P ¼.002). The bursting pressure for MAS-EVSMT (median 398.5 cmH2O) was not significantly different from the SA-EVSMT (median 321 cmH2O, P ¼.567); however, the creation of an SMT significantly increased the bursting pressure for both techniques (P ¼.028, respectively). Conclusion: This study demonstrated the feasibility of a suture-free ureterovesical anastomosis in the canine cadaver using a commercially available MAS. The MAS anastomosis was faster and resulted in higher bursting pressures than SA. The creation of an SMT improved the bursting resistance of both techniques but there was no difference between the techniques covered by an EVSMT.
Ureteral surgery has been described for the treatment of both acquired1–12 and congenital13 conditions in the dog. Primary repair of the ureter using fine suture material is technically demanding, requiring specialized instruments and microsurgical training that are not widely available.13,14 In dogs with distal ureteral obstructions and in those undergoing renal transplantation, direct anastomosis of the ureter to the urinary bladder (ureterovesical anastomosis) is indicated.15–17 While ureterovesical anastomosis is helpful in dealing with luminal disparity that occurs with chronic obstruction, creating a leak-proof anastomosis without luminal narrowing remains technically difficult in dogs with a small ureter.15–17 Surgical techniques for ureterovesical anastomosis are described as intra or extravesicular.16,17 Intravesicular techniques such as the LeadbetterPolitano technique (mucosal apposition) are performed through a cystotomy to access the urinary bladder lumen.17 Extravesicular techniques such as the Lich-Gregoir technique do not required a cystotomy.17,18 Reported complications of ureterovesical
anastomosis include urine leakage, granuloma formation, ureteral obstruction, and chronic hematuria.19 Some surgeons have adopted a modified Lich-Gregoir technique, which allows an extravesical anastomosis that is covered by closure of the mucosal anastomosis in a seromuscular tunnel.17,18 The successful use of a commercially available microanastomotic system (MAS) for ureteral anastomosis in the dog using an ex vivo model was recently reported.20 This device, known as the GEM Microvascular Anastomotic COUPLERTM (GEM, Birmingham, AL), has been used in people for microvascular anastomosis and is recommended for vessels having an outside diameter >0.8 and
