51
Retrograde Endopyelotomy
Weil R. Lai & Raju Thomas
Department of Urology, Tulane University School of Medicine, New Orleans, LA, USA
Introduction
Advances in technology, instrumentation, and techniques have changed the practice of urology, especially over the past two decades. One of the areas of major impact has been the treatment of ureteropelvic junction obstruction (UPJO), which is defined as an anatomic or functional impedance of urine flow from the renal pelvis into the ureter [1] (Figure 51.1). This condition can be congenital or acquired, the congenital form being the more common. UPJO, although relatively uncommon, warrants prompt attention to alleviate symptoms and prevent deterioration of renal function. Several factors can play roles in the development of UPJO, including intrinsic aperistalsis of the involved ureteral segment, crossing aberrant vessels causing direct compression of the ureter, renal stone disease, and previous surgical or endourologic manipulation.
Figure 51.1 Intravenous pyelogram of a right ureteropelvic junction obstruction (arrow).
The advent of smaller‐caliber endoscopes [2], and development of laparoscopic reconstructive techniques, laser technology, and robotics has diversified the treatment options for this condition.
Although the efficacy, and decreased morbidity, hospital stay, and need for analgesia with endopyelotomy have been clearly demonstrated, several issues have still not been completely resolved. Should patients be managed initially by the ureteroscopic approach? What are the exclusion criteria for these endoscopic procedures? What are the relative merits of antegrade versus retrograde approaches? In the era of minimally invasive laparoscopy and robot‐assisted surgery, is there still a role for retrograde ureteroscopic endopyelotomy?
In this chapter we discuss the technique and results at our institution for retrograde ureteroscopic endopyelotomy for the treatment of UPJO.
History
Several reconstructive procedures have been described for the management of UPJO since Trendelenburg’s first description of such a procedure in 1886. Open surgical correction was the only mode of treatment for this condition before the introduction of endoscopic and laparoscopic techniques, and has been considered the gold standard of treatment for this condition, with success rates of over 90% [3]. However, associated morbidity is not unusual with open surgery. Specifically, there is fistula formation in 2.6% of patients, stricture of the ureteropelvic junction (UPJ) in 2.4%, and the need for nephrectomy in 3.2% [4].
The present‐day endourologic approach to the management of UPJO can be traced back to the original descriptions of Albarran, Keyes, and Davis. Albarran did the first endosurgical repair of the UPJO in 1903, which actually described a ureterotome externe [5]. Keyes performed a similar procedure successfully in 1915 [6]. Both the antegrade and retrograde endopyelotomy follow the concept of Davis’s intubated ureterotomy, first described by Davis in 1943. In 1985, Bagley et al. reported a combined percutaneous and flexible ureteroscopic approach for the management of an obliterated UPJ [7]. Wickham and Kellet described the first ureteroscopic pyelolysis of the UPJ in 1983 [8], and this was repeated by Inglis and Tolley in 1986 [9]. Thomas et al. described their experience of ureteroscopic endopyelotomy in which pre‐stenting was performed to facilitate ureteroscopy in 1996 [10]. A single‐setting, one‐stage procedure was subsequently described by Soroush and Bagley in 1998 [11].
There are now multiple different options for the treatment of UPJO, including antegrade nephroscopic endopyelotomy, retrograde ureteroscopic endopyelotomy, Acucise™ (Applied Medical, Rancho Santa Margarita, CA, USA), and laparoscopic and robot‐assisted pyeloplasty, as well as the traditional open surgical pyeloplasty [12]. As mentioned above, open surgical dismembered pyeloplasty has been considered the gold standard for the treatment of UPJO, with success rates of over 90%. However, many institutions have considered endopyelotomy a possible first‐line therapy option for the treatment of this condition [13–16].
Currently, a retrograde endopyelotomy can be performed in three ways: (i) using a rigid ureteroscope and a cold‐knife, electrocautery, or holmium laser incision; (ii) using a flexible ureteroscope and electrocautery or laser incision; and (iii) in rare select cases, using a balloon with a cutting wire (Acucise) [15]. The technique of dilation and cold‐cut incision with a peripheral cutting balloon, which was originally designed for angioplasty, had been reported mainly for ureteral strictures other than UPJO [17–19]. For UPJO, a recent retrospective case series was described in infants under 18 months of age [20]. This has not yet been reported in literature for adult patients with UPJO. It must be mentioned that the use of Acucise is not recommended for primary UPJO because of incidences of hemorrhage following use of this device.
Different series have reported success rates for retrograde ureteroscopic endopyelotomy to be in the range of 73–90% [10, 11, 21–24]. As compared with other treatment options, ureteroscopic retrograde endopyelotomy is less invasive, requires less operating room time, enables the procedure to be performed on an outpatient basis or with a very short hospital stay, and is associated with a shorter convalescence period [1, 13, 25–29]. Also, the initial report of ureteral stricture formation because of thermal injury from transmission of the electrocautery current has been eliminated with the use of insulated ureteroresectoscopes and electrocautery and rigid or flexible ureteroscopes with holmium laser fibers [30]. With the miniaturization of ureteroscopes, the use of the rigid resectoscope is no longer advised.
Patient selection and preoperative preparation
The presumptive clinical diagnosis of UPJO can be evaluated and/or confirmed with a renal ultrasound, intravenous pyelogram (IVP), diuretic renal scan, retrograde pyelogram, computed tomography (CT) scan, Whitaker test, or with a combination of these, as is clinically indicated. The renal scan, besides aiding in the diagnosis of a UPJO, gives a quantitative differential renal function, which can be used to choose the best treatment option and, further, to allow for follow‐up evaluation of the renal function.
A high‐resolution spiral CT angiography is highly recommended to assess for the presence of an aberrant crossing vessel. For practitioners with experience and access to endoluminal ultrasound equipment, it can also be used to identify crossing vessels [31]. The UPJ area can also be evaluated ureteroscopically for the presence of pulsations before performing the endopyelotomy incision.
Although ureteroscopic retrograde endopyelotomy is applicable to most patients with UPJO, there are some absolute and relative exclusion criteria. Among the absolute contraindications are patients with active infection and bleeding diathesis.
Patients with concurrent renal calculi and UPJO, and patients with a nephrostomy tube in place, should be treated with an antegrade approach so that both the renal stone and the UPJO can be managed in a one‐stage procedure. Patients with a relatively long length of obstruction, usually greater than 2 cm, are best managed either with open surgical, laparoscopic, or robot‐assisted techniques. Patients with ipsilateral differential renal function of less than 20% and severely decreased parenchymal thickness can be given a trial of drainage and re‐evaluation [15] or should be offered a laparoscopic simple nephrectomy for a poorly functioning or nonfunctioning kidney. Patients with massive hydronephrosis should be treated with dismembered pyeloplasty, either open surgical, laparoscopic, or robot‐assisted, because of the need for trimming and reduction of the redundant renal pelvis. Controversy exists with regard to patients with high insertion of the UPJ and crossing vessels. Although once considered a contraindication because of poor results, published series report that the type of ureteral insertion has no significant impact on the outcome of endopyelotomy [32], and that patients with crossing vessels had long‐term success with retrograde endopyelotomy [14]. We routinely perform laparoscopic robot‐assisted pyeloplasty in both cases with a high insertion UPJO or a known crossing vessel [12]. In the case of recurrent UPJO after pyeloplasty in adult patients, a trial of retrograde endopyelotomy should be considered as it has been noted to have success rates greater than 80% in such cases [33]. Lastly, patients with known intractable stent intolerance should be considered candidates for either an antegrade endopyelotomy or an open pyeloplasty with a nephrostomy tube, and not for ureteroscopic endopyelotomy.
Once the surgeon and patient have decided on the retrograde approach for management of a UPJO, an indwelling ureteral stent is usually placed to drain the obstructed renal unit for 1–2 weeks. This procedure not only drains the obstructed renal unit, but also stabilizes its renal function, dilates and straightens the UPJ, and facilitates subsequent passage of the ureteroscope into the renal pelvis. Above all, preoperative placement of the stent allows evaluation of any degree of stent intolerance and may identify improvement of renal function after drainage.
Informed consent
On the day of the scheduled endopyelotomy, any final questions are answered, and an informed consent is obtained after explaining and discussing with the patient the expected outcomes and benefits of the procedure (e.g. improved renal drainage, preservation of renal function, diminished risk of calculus and infection, minimally invasive procedure), its associated risks or complications (bleeding, infection, possibility of conversion to open surgery, recurrence, etc.), and the other minimally invasive treatment options available. Patients are informed that postoperative evaluations may show some residual pelvicaliectasis, especially in those with long‐standing UPJO.
Step‐by‐step operative technique
The required instrumentation is listed in Table 51.1. After either a general or a spinal anesthesia, the patient is placed in the lithotomy position. Caution is taken so that all pressure points are well cushioned, and antiembolic stockings are used in high‐risk patients. With the use of a cystoscope, and under fluoroscopic guidance, a retrograde pyelogram is performed to confirm the length of the UPJO segment, and subsequently a super‐stiff guidewire is passed and coiled into the renal pelvis. If the patient had a previously placed indwelling ureteral stent, it is removed and used to pass the guidewire prior to removing the stent. A retrograde pyelogram can assess for any resolution of hydronephrosis and can be used as a prognostic indicator.
Table 51.1 Required instrumentation.
| Holmium laser ureteroscopic endopyelotomy | 7.5 Fr rigid and/or flexible ureteroscope |
200 or 365 µm holmium laser fiber at the following settings:
| |
| Super‐stiff guidewire (0.038 inch) | |
| Single Action Pumping System (Boston Scientific, Marlborough, MA, USA) | |
| Endopyelotomy stent (Boston Scientific or Applied Medical, Rancho Santa Margarita, CA, USA) | |
| Routine cystoscopy and fluoroscopy setup | |
| Ureteroscopic endopyelotomy with electrocautery | 11.5 Fr ureteroresectoscope (Karl Storz, Culver City, CA, USA; Richard Wolf, Rosemont, IL, USA) (Figure 51.2):
|
| Single Action Pumping System (Boston Scientific) |
