Others are treated with ureteroscopy, in which a scope is passed through the urethra and bladder and up the ureter into the kidney.

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Complicating matters further: The urethra passes through the center of the prostate and must be reconnected back to the bladder once the prostate is removed.

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In bladder instillation, the prescription medication dimethyl sulfoxide, or DMSO, (Rimso-50) is placed into your bladder through a thin, flexible tube (catheter) inserted through the urethra.

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They had used a small piece of each patient's own tissue from the bladder, then grew the cells in a lab onto a mesh scaffold shaped like a urethra.

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