ultrasound diagnosis of fatal anomalies

URETHRAL VALVE SEQUENCE
Fig. 7.31 Urethral valve sequence. Megacystis at
15 weeks, longitudinal section. No other anomalies,
normal male karyotype.
Fig. 7.32 Urethral valve sequence. Same case, in a
cross-section showing the “keyhole phenomenon.”
There is a small amount of ascites due to a temporary
vesicoabdominal fistula after bladder aspiration.
Fig. 7.33 Urethral valve sequence. Same fetus,
23 + 1, with severe distension of the ureter and unilateral
hydronephrosis.
2
145