Intracorporeal neobladder reconstruction: Pressure-flow urodyamic studies in cadaveric orthotopic neobladders

OBJECTIVE To determine the pressure-flow characteristics of neobladders created in various configurations that may be constructed intra-abdominally. Complete intracorporeal neobladder construction has been previously described but is limited due to excessive operative time and the need for an advanced laparoscopic skill set. MATERIALS AND METHODS Four neobladder configurations were constructed, each using 20 cm of human cadaveric small intestine. The standard hand sewn Studer pouch was compared with a circular loop, W-pouch, and U-pouch with stapled anastamoses. Pressure flow studies were completed using the Aquarius TT UDS system (Laborie Medical Technologies, Toronto, Ontario) and each neobladder was filled to a pressure of 50 cm H2O. Neobladder change in pressure, capacity, and overall compliance were determined. RESULTS The cystometric capacities of the stapled U-pouch, W-pouch, Circle pouch, and Studer pouch were 167.3 mL, 177.5 mL, 114 mL, and 145.2 mL respectively. The first increase in intravesical pressure was at 90.3 mL, 103 mL, 50 mL, and 85 mL. The greatest compliance of 3.81 mL/cmH2O was demonstrated in the U-pouch, with the W-pouch revealing a compliance of 3.44 mL/cmH2O. The least compliant neobladder was the circle pouch (2.24 mL/cmH20) followed by the standard Studer pouch (2.94 mL/cmH2O). CONCLUSION The construction of an orthotopic neobladder must not only be technically feasible but maintain adequate capacity and compliance for optimal functioning. Pressure-flow studies demonstrated equivalent results in alternate neobladder configurations. Additional data is needed to determine feasibility in vivo.