## **Core Concept**
The Anderson-Hynes operation, also known as dismembered pyeloplasty, is a surgical procedure used to correct a condition affecting the renal pelvis and ureter. This operation is primarily associated with the treatment of **ureteropelvic junction (UPJ) obstruction**, a blockage in the area where the renal pelvis transitions into the ureter.

## **Why the Correct Answer is Right**
The Anderson-Hynes operation is specifically designed to alleviate **ureteropelvic junction (UPJ) obstruction** by removing the obstructed segment and then reanastomosing the renal pelvis with the ureter. This procedure involves the dismemberment of the UPJ, allowing for the excision of the stenotic segment and the reestablishment of a wide, unobstructed connection between the renal pelvis and the ureter. The goal is to restore normal urine flow from the kidney to the ureter.

## **Why Each Wrong Option is Incorrect**
- **Option A:** Incorrect because while **pyelolithotomy** involves surgical removal of stones from the renal pelvis, it does not involve the reconstruction of the UPJ.
- **Option B:** Incorrect as **nephrectomy** refers to the removal of a kidney, which is not related to the Anderson-Hynes procedure.
- **Option D:** Incorrect because **ureteric reimplantation** involves changing the insertion point of the ureter into the bladder and is not the primary goal of the Anderson-Hynes operation.

## **Clinical Pearl / High-Yield Fact**
A key point to remember is that the Anderson-Hynes dismembered pyeloplasty is considered the gold standard surgical treatment for **UPJ obstruction** due to its high success rate and versatility in addressing various types of obstructions.

## **Correct Answer:** . Pyeloplasty