Megaureter refluxing

Ureteral dilatation, or hydroureter, is a frequent cause of a dilatation of the fetal urinary tract. Under normal conditions, on fetal or postnatal US, the normal ureter is not visualized. Once it is visible (Fig. 5.20), a urinary tract dilatation is present and must be investigated (Keller and Weiss 1993). The presence of a dilated ureter may correspond to primary megaureter (MU), to refluxing MU (see Chap. 11), to nonobstructive nonrefluxing hydro-ureter, or to secondary hydroureter. The various imaging techniques will be necessary in order to differentiate between these entities. 

Megacystis-megaureter association (high-grade reflux)... 

The main differential diagnosis is the megacys-tis-megaureter association (Willi and Lebowitz 1979 Reuter and Lebowitz 1985), which is due to massive reflux and the phenomenon of aberrant micturition (Fig. 6.5). Prenatal diagnosis is relatively straightforward in female fetuses, but more subtle in males (absence of a dilated posterior urethra). 

In the megacystis-megaureter association, massive bilateral grade IV or V VUR is present. During micturition, the bladder empties normally through the urethra, but also through reflux into the ureters (Fig. 11.23a-d). At the end of micturition, the bladder is completely empty, but only for a very short time. It refills immediately with the refluxed urine ... 

Blane CE, Zerin MJ, Bloom DA (1994) Bladder diverticula in children. Radiology 190 695-697 Blickman JG, Lehowitz RL (1984) The coexistence of primary megaureter and reflux. AJR 143 1053-1057 Blickman J, Taylor G, Lehowitz R (1985) VCU the initial study in children with UTL Radiology 156 659-662 Blyth B, Passerini-Glazel G, Camuffo C et al (1993) Endoscopic incision of ureteroceles intravesical versus ectopic. J Urol 149 556-559... 

Postoperative imaging in children with primary obstructive megaureter includes a micturating cystogram to rule out reflux. Follow-up ultrasonography and radionuclide scintigraphy are performed at 3-6 months. 

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