Real-time indocyanine green angiography with the SPY fluorescence imaging platform decreases benign ureteroenteric strictures in urinary diversions performed during radical cystectomy.

BACKGROUND: Ischemia is thought to contribute to benign ureteroenteric stricture (UES) after radical cystectomy with urinary diversion (RCUD). Our institution adopted the use of ureteral perfusion assessment during all RCUDs using real-time indocyanine green angiography using the SPY fluorescence imaging platform (Stryker Corp., Kalamazoo, MI, USA). This guides the location of ureteral transection prior to ureteroenteric anastomosis. We sought to compare UES rates before and after adoption of SPY. METHODS: A retrospective chart review was undertaken for the first 47 consecutive cases of RCUD using SPY as well as the previous 47 consecutive cases, which were performed without SPY. Fisher's exact and Wilcoxon rank-sum tests were used to compare benign UES rates and the length of ureter excised during anastomosis. A p < 0.05 indicated statistical significance. RESULTS: Median follow up was 12.0 months for SPY cases and 24.3 months for non-SPY cases. The UES rate for SPY RCUDs was 0% (0/93 ureters) compared with 7.5% (7/93 ureters) for non-SPY RCUDs (p = 0.01). Amongst SPY RCUDs, 86 ureters had no hydronephrosis and 7 had mild hydronephrosis with reflux on loopogram. A total of 34.4% of ureters (32/93) had poor distal perfusion, requiring a more proximal anastomosis. The median length excised for ureters with poor distal perfusion was 3.8 cm, compared with 2.2 cm for ureters with good distal perfusion (p < 0.0001). No complications attributable to the use of SPY were noted. CONCLUSION: Use of SPY to assess ureteral perfusion was associated with a decrease in the UES rate after RCUD. A total of 34.4% of ureters demonstrated poor distal perfusion, requiring a significantly more proximal ureteroenteric anastomosis.

Stem cells and tissue engineering applications of the genitourinary tract.

The field of regenerative medicine continues to make substantial advancements in therapeutic strategies addressing urologic diseases. Tissue engineering borrows principles from the fields of cell biology, materials science, transplantation and engineering in an effort to repair or replace damaged tissues. This review is intended to provide a current overview of the use of stem cells and tissue engineering technologies specifically in the treatment of genitourinary diseases. Current themes in the field include the use of adult stem cells seeded onto biocompatible resorbable matrices for implantation as tissue substitutes, which is conducive to host tissue in-growth. Injection therapy of adult stem cells for organ rehabilitation is also making strong headway toward the restoration of organ structure and function. With new data describing the molecular mechanisms for differentiation, work has begun on targeting tissues for regeneration by genetic modification methods. Promising laboratory discoveries portend the emergence of a new class of clinical therapies for regenerative medicine applications in the genitourinary tract.