ureterocele
description
a ureterocele is a cystic dilatation of the terminal end of the ureter. a simple ureterocele involves a normally positioned ureteral orifice with the distal ureter projecting into the bladder. with ectopic ureterocele the ureteral orifice is found in an abnormal location in the bladder neck or urethra. ectopic ureteroceles frequently involve the upper pole of a double ureter. ureteroceles can be associated with reflux and may cause hydroureter or hydronephrosis unilaterally or bilaterally if the bladder neck or urethra are obstructed. ureteroceles are three to four times more common in females, more commonly unilateral and on the left (10-15% bilateral). ectopic ureteroceles are rare but more common in males and are frequently associated with other anomalies such as duplications, crossed-fused ectopia, dysplastic kidneys, abnormal testes and cardiac anomalies. the embryology is unknown but may result from delayed absorption of the developing ureter into the urogenital sinus, or may be associated with arrested muscular development of the distal ureter. familial occurrence has been seen.
diagnosis
a ureterocele is identified as a cystic structure in the full fetal bladder. it may be unilateral or bilateral and is considered simple if it is in the normal position for the ureteral orifice. it is considered ectopic if found in another location usually the bladder neck or urethra. obstruction and renal duplication anomalies are frequently associated findings. dysplastic kidneys, genital and cardiac malformations may also be present. whenever hydronephrosis or hydroureter are identified, a careful examination of the full bladder is important to identify an associated ureterocele.
differential diagnosis
ureterocele may be missed if the fetal bladder is not full. other pelvic cysts (e.g. ovarian cyst) can be identified in a location outside the fetal bladder by observing bladder filling and emptying. distension of the ureterocele may be intermittent; it may not be identified on every serial exam. therefore, associated clinically significant obstruction can also be intermittent.
sonographic features
cystic structure seen in full bladder (near ureteral orifice) simple – ureteral orifice in normal position, commonest in females and on left side ectopic – ureteral orifice in bladder neck or urethra. rare and commonest in males. other anomalies frequent; duplications, crossed-fused ectopia, dysplastic kidneys, abnormal testes, cardiac anomalies distension may be intermittent obstruction and/or reflux may be present
associated syndromes
- 13 ring
- 8 trisomy/ trisomy 8 mosaicism
- brachio-oto-renal
- congenital hydronephrosis
- diabetes
- familial ureterocele
- trisomy 13
- trisomy 18
- turner
references
fleischer a, romero r, manning f, jeanty p, james jr a in: the principles and practice of ultrasonography in obstetrics and gynecology, 4th ed appleton & lange: norwalk, p266-267
stevenson r, hall j, goodman r in: human malformations and related anomalies vol. ii oxford u press: oxford, p503-505
mckusick v in: mendelian inheritance in man, vol. ii, 10th ed johns hopkins u press: baltimore, p1129
mandell j, colodny ah, lebowitz r ureteroceles in infants and children j urol vol 123:921-926
abrams mj, sutton ap, buchbinderbel ureteroceles in siblings j urol vol 124:135
ayalon a, shapiro a, rubin sz ureterocele – a familial congenital anomaly urology 13:551