Ultrasound guided balloon catheterisation: a new method of fetal lower urinary tract obstruction management

Fetal lower urinary tract obstruction (LUTO), most often associated with presence of posterior urethral valves, poses high risk of perinatal mortality or postnatal renal failure. Looking for a method of causative treatment we have devel-oped a technique of fetal urethroplasty with a coronary angioplasty balloon catheter inserted under an ultrasonographic guidance via an 18-gauge needle introduced transabdominally to fetal bladder.

We have used this procedure in three women with singleton pregnancies (two primiparas and one multipara, 32-35 years of age), diagnosed with fetal megacystis at 12-16 weeks of gestation. Urethral catheterization was carried out at 16-18 weeks and an unobstructed urine flow was achieved in all three cases immediately after the procedure, followed by a resolution of megacystis and normalization of amniotic fluid volume.

In all three cases, the post-procedure period was uneventful. In the first two fetuses, amniotic fluid volume re-mained normal until 30 weeks of gestation when a gradual development of oligohydramnios and some signs of renal cystic dysplasia were observed. Nevertheless, both pregnancies were continued till term (37 and 39 weeks, respectively) and two boys without signs of pulmonary hypoplasia were delivered. The third patient is currently 25 weeks pregnant; volume of amniotic fluid in her fetus is normal and no signs of urinary flow obstruction or renal dysplasia have been recorded thus far.

Although some technical aspects of the procedure still need to be established, it seems worth consideration as a form of potentially least traumatic intrauterine intervention in fetuses with lower urinary tract obstruction.