AUTHOR AND EDITOR INFORMATION

Section 1 of 11  

• Authors and Editors
• Introduction
• Indications
• Relevant Anatomy
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

INTRODUCTION

Section 2 of 11  

• Authors and Editors
• Introduction
• Indications
• Relevant Anatomy
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Both adult and pediatric urologists frequently encounter patients with ureteropelvic junction (UPJ) obstruction. Congenital abnormalities may be observed in both groups, but adults also may present with obstruction following previous surgery or other disorders that can cause inflammation of the upper urinary tract.

The critical decision to be made is whether or not the radiologic findings correlate with the physiologic picture. In other words, those patients with severely dilated hydronephrotic kidneys may, in fact, drain well when studied appropriately. Defining the exact anatomy and function of these kidneys is crucial when evaluating and treating these patients.

History of the Procedure

UPJ obstruction is the most common cause of antenatal and neonatal hydronephrosis. Prior to the use of prenatal ultrasound, most patients with UPJ obstruction presented with pain, hematuria, urosepsis, failure to thrive, or a palpable mass. With the enhanced ability and availability of prenatal ultrasound, urologic abnormalities are being diagnosed earlier and more frequently. Fifty percent of patients diagnosed with antenatal hydronephrosis will be diagnosed with a UPJ obstruction upon further workup.

Problem

UPJ obstruction is defined as an obstruction of the flow of urine from the renal pelvis to the proximal ureter. The resultant back pressure within the renal pelvis may lead to progressive renal damage and deterioration.

UPJ obstruction presents most frequently in childhood, but adults and elderly individuals also can present with a primary obstructive lesion. In adults, other etiologies for ureteral obstruction must be considered, including stones, ureteral compression from extrinsic processes, retroperitoneal fibrosis, and other inflammatory processes.

Frequency

• Approximately 1 in 100 pregnancies are noted to have fetal upper tract dilation on ultrasound. However, only 1 in 500 will be found to have significant urologic problems.
• UPJ obstruction is found in approximately 50% of patients diagnosed with antenatal hydronephrosis.
• The male-to-female ratio is 3-4:1.
• In general, the left kidney is affected more commonly than the right kidney.
• This disorder is encountered less frequently in adults, but it is not a rarity in this population.

Etiology

Possible etiologies for UPJ obstruction include the following:

• Intrinsic obstruction may occur secondary to stenosis from scarring of ureteral valves.
• Ureteral hypoplasia may result in abnormal peristalsis through the UPJ. Asymmetry of ureteral wall musculature may inhibit the natural peristaltic emptying of the renal pelvis into the ureter.
• Abnormal or a high insertion of the ureter into the renal pelvis may cause an altered configuration and impaired drainage of urine. This may be an effect rather than a cause because the 2 etiologies mentioned previously may present with a high-insertion variant seen on imaging studies.
• Crossing lower pole renal vessel(s) or entrapment of the ureter by a vessel can prohibit urinary flow down the ureter. Vessels that wrap around the UPJ may be associated with obstruction or can be a product of renal dilation and hydronephrosis that distorts renal vascular architecture.
• Rotation of the kidney, such as renal ectopy, and renal hypermobility can cause intermittent obstruction that is solely dependent on the position of the kidney relative to the ureter. This was once a very popular diagnosis, but today, the other aforementioned etiologies are more prevalent and this cause is particularly rare.
• Secondary UPJ obstruction can be caused by prior surgical intervention for other disorders, such as renal stone disease or failed repair of a primary UPJ obstruction. This obstructive lesion most commonly is secondary to ureteral wall and periureteral scar formation.

The above abnormalities all cause impaired drainage of urine from the kidney into the ureter, resulting in elevated intrarenal back pressure, dilation of the collecting system, and hydronephrosis.

Clinical

Neonates presenting with hydronephrosis should be fully evaluated with both a voiding cystourethrogram (VCUG) to rule out vesicoureteral reflux and a renal ultrasound soon after birth. These patients also should also be placed on prophylactic antibiotics (amoxicillin 15 mg/kg) to prevent urinary tract infections (UTIs), especially while diagnostic imaging is being obtained. If renal sonography demonstrates hydronephrosis without reflux on VCUG, a diuretic renal scan (mercaptotriglycylglycine [MAG-3], diethylenetriamine [DTPA], or dimercaptosuccinic acid [DMSA]) should be performed to quantify relative renal function and to define the extent of obstruction.

Older children may present with UTIs, a flank mass, or intermittent flank pain secondary to a primary UPJ obstruction. Hematuria also may be a presenting sign if associated with infection.

Adults can present with a variety of symptoms, including back and flank pain, UTI, and/or pyelonephritis. Through a detailed history, the pain may be correlated with periods of increased fluid intake or ingestion of a food with diuretic properties (ie, Dietl crisis).

INDICATIONS

Section 3 of 11  

• Authors and Editors
• Introduction
• Indications
• Relevant Anatomy
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

The goals in treating patients with UPJ obstruction are to improve renal drainage and to maintain or improve renal function.

As mentioned previously, dilation of the intrarenal collecting system or hydronephrosis does not necessarily imply obstruction. Specifically in children, renal pelvic dilation should be followed with serial imaging to assess for changes in dilation, renal parenchymal thickness and/or the presence of scarring, and function. Surgical repair is indicated if a significant differential in serial imaging is present or if progressive deterioration of renal function occurs.

Using this algorithm, patients with hydronephrosis are monitored closely with renal ultrasounds and nuclear medicine renograms every 3-6 months. Similarly, in adults, repair is recommended if ureteral obstruction is demonstrated on nuclear medicine renal scan or intravenous pyelogram (IVP).

RELEVANT ANATOMY

Section 4 of 11  

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• Introduction
• Indications
• Relevant Anatomy
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

The evaluation of an obstructed UPJ requires information about ureteral and surrounding anatomy, renal position and ectopy, associated vasculature, and renal function. Prior to surgical intervention, the surgeon frequently evaluates for renal position/ectopy, mobility, and UPJ anatomy, such as high-insertion variants versus annular stricture variants.

The major vascular supply of the UPJ comes from branches of the renal artery. These vessels usually lie in an anteromedial location in relation to the proximal ureter. Aberrant polar vessels also may be associated with the renal pelvis, causing compression and obstruction of the collecting system (see Image 7). These vessels arise from either the renal artery from a position proximal to the main intrarenal branching site or directly from the aorta. They can surround the UPJ and can be associated with obstruction, or they may be aberrantly positioned secondary to increasing hydronephrosis.

An endopyelotomy refers to an endoscopic incision of the UPJ, performed to create a more funneled drainage system and to bring the UPJ more dependent or caudad below areas of pathology.

The vascular anatomy at the UPJ becomes crucial when performing an endopyelotomy. The renal collecting system may be accessed percutaneously (antegrade) or in a retrograde fashion where a ureteroscope is passed through the urethra, bladder, and ureter to access the obstruction and perform an incision. While most associated UPJ vessels lie in the anteromedial plane, accessory vessels may lie posteriorly or laterally. If all endoscopic incisions are made in the posterior-lateral plane, intraoperative hemorrhage may occur. For this reason, a comprehensive vascular evaluation with intraoperative endoluminal ultrasound, preoperative CT scan, or MRI with vascular reconstruction is recommended prior to this form of treatment (see Image 5 and Image 6).

Multidetector CT scan with 3-dimensional reconstruction can be particularly helpful in establishing the anatomy of UPJ obstruction, revealing an intrinsic or high-insertion UPJ. Crossing vessels and their relationship to the ureter of the UPJ can also be evaluated. The location of these vessels and their possible contribution to renal obstruction can help the surgeon clinically decide whether endopyelotomy, open pyeloplasty, or laparoscopic pyeloplasty would be the most effective treatment modality.

When an open or laparoscopic pyeloplasty is performed, an accurate understanding of the vascular anatomy allows the surgeon to preserve the accessory renal vessels and to redirect them if the surgeon feels that they contribute to the obstruction. If an endopyelotomy is planned, this information can guide the surgeon in directing the endopyelotomy incision away from crossing vessels.

WORKUP

Section 5 of 11  

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• Introduction
• Indications
• Relevant Anatomy
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Lab Studies

• All patients should be evaluated with a CBC count, coagulation profile, electrolyte level, and assessment of overall renal function with BUN and creatinine and urine culture.

Imaging Studies

• In children, a renal ultrasound and VCUG are performed (see Image 4).
• Historically, an IVP was used to evaluate patients with possible UPJ obstruction.
• • However, in the evaluation of a child with a hydronephrotic kidney, diuretic renograms have taken the place of the IVP.
  • The benefits are that iodine-based intravenous contrast is not used, radiation exposure is minimal, and renal function can be better quantified. The disadvantage of the nuclear medicine scan is that insight into renal anatomy is not obtained.
• In 1992, the Society for Fetal Urology and the Pediatric Nuclear Medicine Council published guidelines for the "Well-Tempered Diuresis Renogram."
• • Standardized protocols for hydration, radiopharmaceuticals, bladder catheterization, diuretic dose, timing of diuretic, and determination of clearance half time (T 1/2) have been established.
  • Those patients with split renal function of less than 40% and obstruction noted by a T 1/2 of greater than 20 minutes appear to be at significant risk of renal deterioration if intervention is delayed.
• The evaluation of ureteral anatomy is difficult with the nuclear medicine renal scan.
• • In adult patients, an IVP outlining this anatomy is obtained more frequently and often can replace the nuclear medicine scan (see Image 1).
  • Multidetector CT scan with 3-dimensional reconstruction may be used to help establish the anatomy of UPJ obstruction and associated vessels.
  • In children, a retrograde ureteropyelogram sometimes is performed to define the entire ureter just prior to surgical repair (see Image 2 and Image 3).

Diagnostic Procedures

• In those patients in whom the diagnosis of obstruction is equivocal, a Whitaker antegrade pressure-flow study may be performed.
• • This test begins with the placement of a small-diameter nephrostomy through the back and directly into the kidney.
  • Dilute contrast medium is instilled, and the intrarenal collecting system is pressure-monitored. Under fluoroscopy, the UPJ is assessed and drainage through this segment is defined.
  • While function cannot be assessed, relative resistance and pressure within the renal pelvis can be determined. High intrarenal pressures define obstruction, while low pressures in the presence of hydronephrosis are consistent with normal variance. This is particularly useful in large dilated systems where the renal pelvis must be completely full prior to assessing drainage. In this setting, nuclear medicine scans can give false-positive results.

TREATMENT

Section 6 of 11  

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• Introduction
• Indications
• Relevant Anatomy
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Medical therapy

In children, medical therapy is focused on maintaining sterile urine and assessing renal function and the degree of hydronephrosis. Typically, if an incomplete obstruction is defined after imaging studies, patients are monitored with routine renal ultrasounds and nuclear medicine renograms.

In both children and adults, presently, no medical therapy is available for treatment of an obstructed UPJ.

Surgical therapy

Surgical intervention to treat an obstructed UPJ is warranted, especially with deterioration of renal function.

• The principles of surgical repair, as initially described by Foley, include the following:
• • Formation of a funnel
  • Dependent drainage
  • Watertight anastomosis
  • Tension-free anastomosis

In children, the procedure of choice is an Anderson-Hynes dismembered pyeloplasty. The approach may be performed through a flank, dorsal lumbotomy, or anterior extraperitoneal technique. Laparoscopy has gained increasing acceptance in pediatric surgery and is often used to perform pyeloplasties in children. Laparoscopic pyeloplasty is often not technically feasible in very small children and infants because of space constraints. Using this method, the obstructed segment is completely resected, with reanastomosis of the renal pelvis and ureter in a dependent funneled fashion. The decision whether or not to employ a ureteral stent transiently during the initial healing is based on the personal preference of the surgeon. The success rate of dismembered pyeloplasty for treating an obstructed UPJ is higher than 95%.

Laparoscopic pyeloplasty offers a minimally invasive treatment option that may be used in patients with either primary or secondary UPJ obstruction and is emerging as a new criterion standard in the treatment of UPJ obstruction. Success rates are comparable with those of open pyeloplasty procedures, and some studies have shown that laparoscopy offers the advantages of decreased morbidity, shorter hospital stay, and quicker recovery. Laparoscopic pyeloplasty is a technically demanding procedure that generally requires significant laparoscopic experience. Robotic-assisted laparoscopic pyeloplasty has become increasingly popular as the robots have become more prevalent. A small intrarenal pelvis is a relative contraindication for laparoscopic pyeloplasty.

Endoscopic treatment alternatives include an antegrade or retrograde endopyelotomy, which is an endoscopic incision performed through the obstructing segment.

Prior to incising a UPJ obstruction, intraluminal ultrasound or other imaging is recommended to evaluate adjacent ureteral vasculature. Endoluminal sonography is particularly useful in evaluating an obstructed UPJ because it allows for complete real-time evaluation with specific attention to the presence or proximity of blood vessels prior to an endoscopic incision. It also is useful for defining the ureteral anatomy and directing the incision technique in order to maximize the surgical outcome.

An endopyelotomy incision is performed through the area of obstruction with a laser, electrocautery, or endoscopic scalpel. Most surgeons dilate the newly incised area with a balloon catheter to help ensure a complete incision. This is followed by prolonged ureteral stenting for a period of 4-8 weeks. The stent acts as internal scaffolding during healing, while also maintaining renal drainage. Success rates with the percutaneous and ureteroscopic endopyelotomy are 80-90%.

In those patients who fail open pyeloplasty, endopyelotomy is particularly useful, even in the pediatric population.

In those patients who have a suboptimal result from endopyelotomy, repeat incision can be performed with success. Traditional open or laparoscopic pyeloplasty also is indicated after failed endopyelotomy.

Of the open surgical repairs performed for UPJ obstruction, the Anderson-Hynes dismembered pyeloplasty is particularly useful for the high-insertion variant. The benefit of this procedure is complete excision of the diseased segment of ureter and reconstruction with healthy viable tissue.

The Foley Y-V plasty also is useful for the high-insertion variant but cannot be used if transposition of a lower pole vessel is needed.

Endopyelotomy for high-insertion UPJ obstruction is patterned after this open surgical procedure and also is contraindicated in the presence of a crossing posterior or lateral vessel.

Spiral and vertical flaps (eg, Culp and DeWeerd, Scardino and Prince) are useful when a long-strictured segment of diseased ureter is encountered. With these procedures, the proximal ureter is re-created with redundant renal pelvis that is tubularized.

Ureterocalicostomy, ie, anastomosis of the ureter to a lower pole renal calyx, most often is reserved for failed open pyeloplasty where no extrarenal pelvis and significant hilar scarring are present. With this procedure, the ureter is sutured directly to a lower pole calyx after a modest partial nephrectomy is performed to remove parenchyma in the area of anastomosis.

Preoperative details

• History and physical exam
• Evaluation of CBC, electrolytes, renal function, and coagulation profile
• Radiographic and functional studies of the kidney in question
• Evaluation of the normal contralateral kidney
• Evaluation of peri-UPJ vascular anatomy
• Anesthesia evaluation

Intraoperative details

Techniques of surgical repair of an obstructed ureteropelvic junction

One of the goals of laparoscopy is to mirror open techniques, so most of the principles of surgical repair apply to both. In addition to creating a funnel with dependent drainage, care must be taken to minimize tissue handling and tension on the reconstructed UPJ. Whether to use ureteral stents or nephrostomy tubes after open or laparoscopic repair is based on personal preference.

Principles of endopyelotomy

It may be performed either antegrade or retrograde, ureteroscopically. A safety guide wire must be placed within the ureter prior to endoscopic incision. Intraluminal ultrasound or preoperative imaging used to define peri-UPJ vascular anatomy is essential.

Endoscopic incision should be performed full-thickness through the UPJ and into perirenal fat with laser energy, electrocautery, or an endoscopic scalpel. To ensure a proper incision, extravasation of contrast should be seen on pyelography during the procedure. The incision most commonly is performed posterolaterally.

Balloon dilation often is performed after the incision to ensure completeness. Ureteral stenting for 4-8 weeks after the endoscopic procedure is common, although no consensus exists regarding size and duration of stents.

Postoperative details

• Risk factors for failure after endopyelotomy include the following:
• • Length of UPJ obstruction
  • Diminished renal function (<25%)
  • Massive hydronephrosis with a redundant renal pelvis
  • Crossing vessels
  • Crossing vessels with massive hydronephrosis (worst outcome)

Follow-up

Prophylactic antibiotic therapy should be given postoperatively. Remove the endopyelotomy stent after 4-8 weeks.

Follow up with renal ultrasound 1-3 months after surgery. Also, follow up with IVP or nuclear medicine renal scan 3-6 months after surgery.

Serial renal imaging is recommended for the first year after surgery and should be continued less frequently thereafter if results have normalized.

For excellent patient education resources, visit eMedicine's Kidneys and Urinary System Center. Also, see eMedicine's patient education articles Intravenous Pyelogram and Adhesions, General and After Surgery.

COMPLICATIONS

Section 7 of 11  

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• Introduction
• Indications
• Relevant Anatomy
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Potential complications from open surgical pyeloplasty include UTI and pyelonephritis, urinary extravasation and leakage, recurrent UPJ obstruction, or stricture formation. Treatment of urinary leakage is based on catheter drainage, such as nephrostomy, ureteral stent, or perianastomotic drain, to direct urine away from the perianastomotic tissues and decrease the risk of postoperative stricture disease.

Specific complications from endopyelotomy include significant intraoperative bleeding if the endoscopic incision is made inadvertently into a major polar vessel, postoperative infection, and recurrence of obstruction. If significant intraoperative bleeding is encountered with hypotension, emergency arteriography and embolization are indicated.

OUTCOME AND PROGNOSIS

Section 8 of 11  

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• Indications
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• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

The long-term success rate for open and laparoscopic pyeloplasty is higher than 95%. The success rate for endopyelotomy approaches 80-90%.

FUTURE AND CONTROVERSIES

Section 9 of 11  

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• Introduction
• Indications
• Relevant Anatomy
• Workup
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• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

The future of treatment of UPJ obstruction will certainly include a broadening of the application of laparoscopic techniques. As laparoscopic pyeloplasty has gained acceptance and the surgical experience increased, the procedure has become shorter. The use of robotic assistance may broaden the application of laparoscopy.

MULTIMEDIA

Section 10 of 11  

• Authors and Editors
• Introduction
• Indications
• Relevant Anatomy
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

Media file 1:  Intravenous pyelogram demonstrating a ureteropelvic junction obstruction with dilation of the collecting system and lack of excretion of contrast.
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Media file 2:  Retrograde pyelogram demonstrating a ureteropelvic junction obstruction secondary to annular stricture.
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Media file 3:  Retrograde pyelogram demonstrating a ureteropelvic junction obstruction secondary to crossing vessels (see Picture 6 for CT scan with intravenous contrast of this patient).
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Media file 4:  Intraluminal ultrasound of ureteropelvic junction obstruction shown in Picture 3 demonstrating multiple crossing vessels.
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Media file 5:  CT scan without contrast demonstrating severe left-sided hydronephrosis secondary to a ureteropelvic junction obstruction.
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Media type:  CT

Media file 6:  CT scan with intravenous contrast demonstrating pooling of contrast and delayed excretion of contrast from a left-sided ureteropelvic junction obstruction (see Picture 3 for retrograde pyelogram of this patient).
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Media type:  CT

Media file 7:  Intraluminal ultrasound demonstrating the renal vein surrounding the ureteropelvic junction and causing extrinsic compression and obstruction.
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REFERENCES

Section 11 of 11

• Authors and Editors
• Introduction
• Indications
• Relevant Anatomy
• Workup
• Treatment
• Complications
• Outcome And Prognosis
• Future And Controversies
• Multimedia
• References

• Bagley DH, Liu JB. Endoureteral sonography to define the anatomy of the obstructed ureteropelvic junction. Urol Clin North Am. May 1998;25(2):271-9. [Medline].
• Baniel J, Livne PM, Savir A. Dismembered pyeloplasty in children with and without stents. Eur Urol. 1996;30(3):400-2. [Medline].
• Casale P, Grady RW, Joyner BD, et al. Comparison of dismembered and nondismembered laparoscopic pyeloplasty in the pediatric patient. J Endourol. Nov 2004;18(9):875-8.
• Chow GK, Geisinger MA, Streem SB. Endopyelotomy outcome as a function of high versus dependent ureteral insertion. Urology. Dec 1999;54(6):999-1002. [Medline].
• Conway JJ, Maizels M. The "well tempered" diuretic renogram: a standard method to examine the asymptomatic neonate with hydronephrosis or hydroureteronephrosis. A report from combined meetings of The Society for Fetal Urology and members of The Pediatric Nuclear Medicine C. J Nucl Med. Nov 1992;33(11):2047-51. [Medline].
• Figenshau RS, Clayman RV. Endourologic options for management of ureteropelvic junction obstruction in the pediatric patient. Urol Clin North Am. May 1998;25(2):199-209. [Medline].
• Frauscher F, Janetschek G, Helweg G. Crossing vessels at the ureteropelvic junction: detection with contrast- enhanced color Doppler imaging. Radiology. Mar 1999;210(3):727-31. [Medline].
• Jabbour ME, Goldfischer ER, Klima WJ. Endopyelotomy after failed pyeloplasty: the long-term results. J Urol. Sep 1998;160(3 Pt 1):690-2; discussion 692-3. [Medline].
• Johnston JH, Evans JP, Glassberg KI. Pelvic hydronephrosis in children: a review of 219 personal cases. J Urol. Jan 1977;117(1):97-101. [Medline].
• Kumar R, Kapoor R, Mandhani A. Optimum duration of splinting after endopyelotomy. J Endourol. Mar 1999;13(2):89-92. [Medline].
• Lee RS, Retik AB, Borer JG, Peters CA. Pediatric robot assisted laparoscopic dismembered pyeloplasty: comparison with a cohort of open surgery. J Urol. Feb 2006;175(2):683-7; discussion 687.
• Lopez-Pujals A, Leveillee RJ, Wong C. Application of strict radiologic criteria to define success in laparoscopic pyeloplasty. J Endourol. Oct 2004;18(8):756-60. [Medline].
• Matlaga BR, Shah OD, Singh D, et al. Ureterocalicostomy: a contemporary experience. Urology. Jan 2005;65(1):42-4.
• Niemczyk P, Krisch EB, Zeiger L. Use of diuretic renogram in evaluation of patients before and after endopyelotomy. Urology. Feb 1999;53(2):271-5. [Medline].
• Park JM, Bloom DA. The pathophysiology of UPJ obstruction. Current concepts. Urol Clin North Am. May 1998;25(2):161-9. [Medline].
• Reddy PP, Mandell J. Prenatal diagnosis. Therapeutic implications. Urol Clin North Am. May 1998;25(2):171-80. [Medline].
• Shalhav AL, Giusti G, Elbahnasy AM. Adult endopyelotomy: impact of etiology and antegrade versus retrograde approach on outcome. J Urol. Sep 1998;160(3 Pt 1):685-9. [Medline].
• Smith AD, Horgan JD. Endopyelotomy and Pyeloplasty. In: Clinical Urology. Philadelphia, Pa: JB Lippincott: 1994:. 433-43.
• Thomas DF. Fetal uropathy. Br J Urol. Sep 1990;66(3):225-31. [Medline].
• Yurkanin JP, Fuchs GJ. Laparoscopic dismembered pyeloureteroplasty: a single institution''s 3-year experience. J Endourol. Oct 2004;18(8):765-9. [Medline].

Article Last Updated: May 22, 2006