Laparoscopic Pyeloplasty in a Solitary Kidney

Nauman Zafar; John Leyland; Nimish C Shah*

Disclosures

Nat Clin Pract Urol. 2007;4(11):625-629. 

In This Article

Treatment and Management

When UPJ obstruction is suspected, radiographic studies are required to give both anatomical and functional information. Ultrasonography and non-contrast CT are most commonly employed as the initial investigations, and these techniques demonstrate hydronephrosis with non-dilated ureter beyond the UPJ. The renal parenchyma may be thin if there has been irreversible impairment of function. Contrast CT and excretory urography with delayed imaging give more information on both obstruction and function of the kidney. It is also important to exclude other causes of obstruction such as malignancy or a calculus. Retrograde pyelography has been the procedure of choice, typically performed at the time of planned operation to confirm diagnosis and demonstrate the exact site and nature of obstruction and placement of a retrograde stent. To a large extent this has been superceded by CT for diagnostic purposes, as good quality contrast CT images, especially with 3D-reconstructive capabilities, can identify crossing vessels at the UPJ that may impact on the choice of surgical intervention, and exclude other causes.

Hydronephrosis in itself does not imply obstruction, and imaging with diuretic renography is important to confirm that obstruction is indeed present.[4] The 99mTc-labeled compound MAG3 is taken up by the kidney, and a gamma camera is used to detect the amount of compound in each kidney during its perfusion through the kidneys and subsequent excretion in the collecting system. With UPJ obstruction there is delayed excretion or 'washout' despite the administration of diuretic. This form of imaging has the added benefit of permitting estimation of divided function in the presence of two kidneys and is increasingly used as a diagnostic test for UPJ obstruction.

The main goals of treatment are the relief of symptoms and the preservation of renal function. Occasionally, in an asymptomatic individual with imaging that is equivocal for obstruction, careful observation with serial follow-up studies may be appropriate.

Initial management includes analgesia and treatment of UTI if present. In most cases the pain is intermittent, as described, or related to concomitant UTI. Investigation and treatment as an outpatient once the patient is clinically stabilized is, therefore, usually feasible. However, in cases of unremitting pain, urosepsis, renal stones or compromised renal function, temporary drainage with a percutaneous nephrostomy tube or cystoscopy and retrograde insertion of a JJ stent may be required until definitive surgical reconstruction can be performed.

The main surgical options for treatment of UPJ obstruction in a functioning kidney include open or laparoscopic pyeloplasty and endopyelotomy performed in an antegrade or retrograde fashion.

Open pyeloplasty has been the traditional gold standard, with long-term success rates of greater than 90%.[5] Pyeloplasty can be performed using a variety of described techniques including the commonly used dismembered Anderson–Hynes pyeloplasty as in this case, which is accomplished by excising the abnormal UPJ segment with re-anastomosis of the ureter to the renal pelvis. Dismembered pyeloplasty allows for posterior transposition of crossing vessels and the reduction of redundant pelvis, but is not well suited to cases in which there is a lengthy stricture or a small, relatively inaccessible intrarenal pelvis. Non-dismembering procedures, which include the Foley Y-V pyeloplasty and Fenger plasty, are suitable in the absence of redundant pelvis, and the various flap techniques described can overcome relatively long areas of proximal ureteral narrowing. Several basic principles apply, whichever technique is employed. A successful outcome requires a widely patent, well-vascularized anastomosis performed in a watertight fashion and free of tension, with a funnel-shaped transition between the renal pelvis and the ureter.

Laparoscopic pyeloplasty was initially introduced by Schuessler et al. in 1993.[6] Laparoscopy aims to duplicate the well-established principles of open surgery, which entails an initial longer operating time, but operating times become equivalent to an open procedure with experience. Numerous studies have shown equivalent success rates to open surgery but with the advantage of reduced morbidity without a flank incision, and with lower analgesic requirement and a shorter hospital stay.[5] Conversion to open surgery is uncommon in experienced series ( Table 1 ). Laparoscopic pyeloplasty can be performed using either a transperitoneal or retroperitoneal approach. The transperitoneal approach gives the advantage of a wider working space and allows for easier displacement of the ureter in the presence of an anterior crossing vessel, whereas the retroperitoneal approach allows for rapid access to the UPJ, and is our choice when performing non-dismembered pyeloplasty.

One of the evolving techniques is robot-assisted laparoscopic pyeloplasty. The use of robotic arms with a greater degree of motion allows for easier intracorporeal suturing, which may be technically difficult for a novice laparoscopist.[7] Short and intermediate term results are similar to laparoscopy without robot assistance, but the technique is less cost-effective.[8]

The technique of endopyelotomy is also a viable treatment option for UPJ obstruction. It can be performed in either antegrade or retrograde fashion using a variety of methods including electrocautery, the Acucise® (Applied Medical Resources, Inc., Rancho Santa Margarita, CA) cutting balloon catheter, and the holmium laser. Success rates of 32­85% have been reported, which are generally lower than with open or laparoscopic pyeloplasty.[9] There is a strong negative association between the presence of a crossing vessel and the success rate of endopyelotomy. Van Cangh et al. have shown that the success rate at 5-year follow-up in the presence of a crossing vessel was 39%, compared with 95% with no crossing vessel.[10]

A novel technique recently described is percutaneous endopyeloplasty. A vertical incision is made at the UPJ internally via a percutaneous nephrostomy tract. This incision is then closed horizontally by a Heineke­Mikulicz technique using a modified laparoscopic suturing device.[11] Initial studies have been promising (100% success in 15 patients with mean 11.6-month follow-up), but the procedure is technically difficult and longer-term data with a larger number of patients are required.[12]

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