Ureteropelvic junction

Taha MA, Shokeir AA, Osman HG, Abd El-Aziz Ael-A, Farahat SE. Obstructed versus dilated nonobstructed kidneys in children with congenital ureteropelvic junction narrowing role of urinary tubular enzymes. J Urol. 2007 178 640-6. 

Fig. 1.83. Ureteropelvic junction obstruction. Longitudinal US scan of the right kidney demonstrates dilated calyces communicating with a markedly dilated renal pelvis (P). No dilated ureter is identified...

Fig.23.1. SSD coronal oblique image in the excretory phase of multidetector CT demonstrates dilation of cali-ces and pelvis in the left kidney due to a stenosis of the ureteropelvic junction...

Fig. 23.2. VR CT-urographic coronal image shows anomalous ureteropelvic junction with dilation of cali-ces and pelvis of both kidneys...

Fig. 1.1.10. Antegrade pyelography combined with the Whitaker test on general anesthesia in a 6-month-old baby. No reflux. Slight dilatation on ultrasound and IVU. Diuresis renography had not been conclusive, and the Whitaker test showed obstruction at the ureteropelvic junction. Surgery was subsequently performed...

Fig. 1.1. 12. Antegrade pyelography combined with the Whitaker test. Intermittent obstruction at the ureteropelvic junction in a child with equivocal results on diuresis renography. Constant flow renal perfusion (5 cc/min). Transient peak in pelvic and differential pressures are shown and complete the criteria for obstruction...

Chertin B, Pollack A, Koulikov D, Rabinowitz R, Hain D, Hadas-Halpren I, Farkas A (2006) Conservative treatment of ureteropelvic junction obstruction in children with antenatal diagnosis of hydronephrosis lessons learned after 16 years of follow-up. Eur Urol 49 734-738 discussion 739... 

Elder JS, Stansbrey R, Dahms BB, Selzman AA (1995) Renal histological changes secondary to ureteropelvic junction obstruction. J Urol 154, Pt 2 719-722... 

Huang WY, Peters CA, Zurakowski D, Borer JG, Diamond DA, Bauer SB, McLellan DL, Rosen S (2006) Renal biopsy in congenital ureteropelvic junction obstruction evidence for parenchymal maldevelopment. Kidney Int 69 137-143... 

Pascual L, Oliva J, Vega-P J, Principi 1, Valles P (1998) Renal histology in ureteropelvic junction obstruction are histological changes a consequence of hyperfiltration J Urol 160, Pt 2 976 discussion 994... 

Rooks VJ, Lebowitz RL (2001) Extrinsic ureteropelvic junction obstruction from a crossing renal vessel demography and imaging. Pediatr Radiol 31 120-124... 

There is a great variation in the configuration of the pelvicalyceal system. The ureteropelvic junction (UPJ) is sometimes sharply defined, sometimes difficult to localize. Filling defects or narrowing at the UPJ without hydronephrosis due to transient contractions or mild, insignificant stenoses are... 

Familial aggregation of hydronephrosis in families with ureteropelvic junction obstruction has been described in several studies. In many cases hydronephrosis can he regarded as manifestation of a spectrum including hydronephrosis - cortical renal cysts (Potter type IV) - hypoplastic/dysplastic or multicystic kidneys - renal agenesis, depending on the time of the interaction of a disruption (e.g. obstruction). Hydronephrosis can also be a part of more complex genetic syndromes (Table 3.4). 

Ureteropelvic junction obstruction by a high ureteral insertion or an anomalous renal vessel is the most common cause of hydronephrosis, which occurs in 30% of patients diagnosed during life. Urolithiasis develops in 20% of patients with a horseshoe kidney. Stasis secondary to hydronephrosis, but with metabolic factors are also the reasons (Evans and Resnick 1981). 

Kramer SASA, Kelalis PP (1984) Ureteropelvic junction obstruction in children with renal ectopy. J Urol 5 331-336... 

Ureteropelvic junction obstruction (UPJ) represents the leading cause of dilatation of the urinary tract (about 35%-40% of the cases). Its origin is not always understood or can be interpreted as multifactorial. UPJ obstruction can result from anatomic anomalies or abnormal peristalsis. At surgery, muscular discontinuity or extrinsic compression of the UPJ due to vessels or ureteral kinks can be found. MR imaging can very nicely display the crossing... 

Riccabona M, Ring E, Fueger G et al (1993) Doppler sonography in congenital ureteropelvic junction obstruction and congenital muticystic kidney disease. Pediatr Radiol 23 502-505... 

Homsy 1995 Homsy et al. 1990 Mouriquand et al. 1999). The most common causes are obstruction at the ureteropelvic junction (UPJ) and fetal VUR. On the basis of the neonatal findings, several authors tend to differentiate between obstructive and nonobstructive UPJ. The other causes of urinary tract dilatation are listed in Table 13.1. The US approach to a dilatation of the fetal urinary tract is similar to that after birth. The aim of US is to... 

Tapia J, Gonzalez R (1995) Pyeloplasty improves renal function and somatic growth in children with ureteropelvic junction obstruction. J Urol 154 218-222 Thomas DFM (1990) Fetal uropathy. Br J Urol 66 225-231 Tibballs JM, De Bruyn R (1996) Primary vesicoureteric reflux how useful is postnatal ultrasound Arch Dis Child 75 444-447... 

Fig. 20.9. A 3-month-old boy with ureteropelvic junction obstruction. Sonogram of right kidney showing hydronephrosis and nephrocalcinosis...

Struvite stones are mainly seen in boys under the age of 5 years (Fig. 20.8). In one-third of patients there is a primary anomaly of the urinary tract, most often a ureteropelvic junction obstruction... 

This classification does not take into account the possible ureteric injuries that are known to be more frequent in children than in adults (Reda and Lebowitz, 1986). Uretero-pelvic junction disruption is the most common location in cases of blunt abdominal trauma it predominates in children with ureteropelvic junction obstruction. Diagnosis is difficult due to the usual absence of hematuria. 

The fundamental techniques of nephrostomy insertion, track dilatation, and stent insertion have led to the development of more sophisticated endou-rologic procedures. The initial percutaneous technique developed was for removal of renal calculi. Within a short time, techniques for treatment of ureteropelvic junction and ureteral strictures were developed. Today percutaneous nephrolithotomy has been replaced in many situations by extracorporeal shock wave lithotripsy (ESWL) and uretero-scopic techniques. However, nonoperative management of staghorn calculi, infected lower pole calculi, or cystine stones via percutaneous nephrolithotomy and lithotripsy is still indicated. 

The success rate of an endopyelotomy for treatment of strictures at the ureteropelvic junction is about 85% with a range of 57%-100% (Towbin et al. 1987 Badlani et al. 1986 Capulicchio et al. 1997 Khan et al. 1997 Kavoussi et al. 1993 Motola et al. 1993). It appears that a failed endopyelotomy does not jeopardize the success of a subsequently performed open surgical procedure. The success rates achieved for endoscopic and percutaneous endopyelotomy are similar (Kavoussi et al. 1993 Brooks etal. 1995). 

Percutaneous surgery is best performed under general anesthesia. Incision of the ureteropelvic junction can be achieved using a variety of methods including a cold knife, electrocautery, or a laser. Percutaneous endopyelotomy is an acceptable alternative for treating congenital UPJ stenosis. 

Badlani G, Eshghi M, Smith A (1986) Percutaneous surgery for ureteropelvic junction obstruction (endopyelotomy) technique and early results. J Urol 135 26-28... 

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