25: Definitive treatment options for ureteral obstruction Flashcards
FIG. 25.5 (A) A spiral flap may be indicated for relatively long areas of proximal ureteral obstruction when the ureteropelvic junction (UPJ) is already in a dependent position. The spiral flap is outlined with the base situated obliquely on the dependent aspect of the renal pelvis. The base of the flap is positioned anatomically lateral to the UPJ, between the ureteral insertion and the renal parenchyma. The flap is spiraled posteriorly to anteriorly or vice versa. The anatomically medial line of incision is carried down completely through the obstructed proximal ureteral segment into normal-caliber ureter. The site of the apex for the flap is determined by the length of flap required to bridge the obstruction. The longer the segment of proximal ureteral obstruction, the farther away is the apex because this will make the flap longer. However, to preserve vascular integrity of the flap, the ratio of flap length to width should not exceed 3:1. (B) Once the flap is developed, the apex is rotated down to the most inferior aspect of the ureterotomy. (C) The anastomosis is then completed, usually over an internal stent, again using fine absorbable sutures.
What indications may call for a spiral flap in treating proximal ureteral obstruction?
A spiral flap may be indicated for relatively long areas of proximal ureteral obstruction when the ureteropelvic junction (UPJ) is already in a dependent position.
Describe the process of outlining and positioning the base of the spiral flap for treating proximal ureteral obstruction.
The spiral flap is outlined with the base situated obliquely on the dependent aspect of the renal pelvis. The base of the flap is positioned anatomically lateral to the UPJ, between the ureteral insertion and the renal parenchyma.
Explain the considerations involved in determining the apex for the flap during the spiral flap procedure.
The site of the apex for the flap is determined by the length of the flap required to bridge the obstruction. The longer the segment of proximal ureteral obstruction, the farther away is the apex. However, to preserve the vascular integrity of the flap, the ratio of flap length to width should not exceed 3:1.
Describe the steps involved in completing the anastomosis during the spiral flap procedure for proximal ureteral obstruction.
Once the flap is developed, the apex is rotated down to the most inferior aspect of the ureterotomy. The anastomosis is then completed, usually over an internal stent, using fine absorbable sutures.
When is the Foley Y-V plasty procedure most appropriately applied, and what does it primarily address?
The Foley Y-V plasty is best applied to a ureteropelvic junction (UPJ) obstruction associated with a high insertion of the ureter, aiming to correct the obstruction.
Describe the first step in the Foley Y-V plasty procedure, including the outlining and positioning of the flap.
The flap is outlined with tissue marker or stay sutures. The base of the V is positioned on the dependent, medial aspect of the renal pelvis, and the apex at the UPJ. The incision from the apex of the flap, representing the stem of the Y, is carried along the lateral aspect of the proximal ureter well into an area of normal caliber.
Explain the steps in developing the flap and completing the posterior wall during the Foley Y-V plasty.
The flap is developed with fine scissors. The apex of the pelvic flap is brought to the most inferior aspect of the ureterotomy incision. The posterior walls are then approximated using interrupted or running fine absorbable suture.
How is the anastomosis completed in the Foley Y-V plasty procedure?
The anastomosis is completed with the approximation of the anterior walls of the pelvic flap and ureterotomy.
