**6.2 Lower urinary tract obstruction (LUTO)**

LUTO can be caused by stenosis of the urethral meatus, valves, urethral atresia, ectopic insertion of a ureter or peri-vesical tumors. Bladder shunts are effective for urine diversion, restoring amniotic fluid and thereby preventing pulmonary hypoplasia. Whether shunting effectively salvages renal function is uncertain. For that, prior accurate assessment of renal function is required. The actual anatomical cause of LUTO proved to be an important predictor. Posterior urethral valves do much better in the long run, while babies with urethral atresias or the Prune Belly phenotype do less well. At the moment, the two commonly used techniques, are percutaneous vesico-amniotic shunting, under ultrasound guide, where double pigtail stent is inserted, usually combined with amnio-infusion. The second procedure is fetal cystoscopy, where fetoscope is inserted into the fetal bladder, to diagnose the

**11**

*6.3.1 IMM repair*

*Principles of Fetal Surgery*

*DOI: http://dx.doi.org/10.5772/intechopen.85883*

**6.3 Intrauterine myelo-meningocele (IMM)**

source of obstruction and to ablate PUV. The commonly used methods to ablate the valve, includes guide wires, hydro-ablation and laser-ablation. The first open clinical fetal surgical intervention for a case of lower urinary tract obstruction (LUTO), not eligible for shunt placement. Instead, fetal ureterostomies were successfully created. There were no maternal complications, but unfortunately the fetus never produced any urine. On the other hand, main complications of shunting include; failure to insert the catheter, occlusion of the catheter, dislocation, and sometimes fistula formation. In order to conclude and evaluate the results of in-utero VAS, and its longterm outcomes, randomized, controlled trial, "Percutaneous vesico-amniotic shunting versus conservative management for fetal Lower Urinary Tract Obstruction" (PLUTO), was performed in the United Kingdom, Ireland, and the Netherlands from 2006 to 2012. The study performed on 31 cases (16 submitted to VAS, 15 undergo conservative treatment). Study reported that fetal cystoscopy, although it is more invasive than VAS, it has the advantage of confirming the diagnosis of PUV, and more accurate in selection of patients who will benefit from valve ablation. In other multi-centric retrospective study includes 50 cases submitted to fetal cystoscopies for treatment of LUTO, 30 fetuses were diagnosed with PUV and were treated with laser-ablation. Other 13 fetuses were diagnosed with urethral atresia, 5 fetus diagnosed with urethral stenosis, and 2 fetuses diagnosed with trisomy 18 (not treated). The results of the 54 fetuses with normal karyotype were, 32.4 weeks mean delivery gestational age, and 34.8% overall 2 years' survival. For PUV patients treated with laser-ablation, 53.6% 2 years' survival. Although 20% (6 of the 30) developed recurrence of LUTO symptoms, and further fetal procedure was performed in 10% (3 patients). Postnatal ablation of PUV was needed in 10 of the 17 survivors. Normal renal function at 2 years of age, was achieved in 75% of infants with PUV (12 of the 16), which considered more promising than the 29% reported in the PLUTO trial with VAS. Reports up to date indicate that, minimally invasive fetal procedure (in selected cases of LUTO), can improve the survival when compared to expectant treatment. However, studies of long term renal function are less encouraging [51–56].

IMM, or Spina bifida, is defined as failure of complete closure of the neural tube with exposure of the spinal canal structures. Lumbar or cervical vertebral levels are the most commonly affected sites, however IMM can occur anywhere along the spine. Neurologic deficits with motor and somato-sensory abnormalities are the most feared complications. In addition, bowel and bladder function may be affected due to injury of autonomic nervous system. Moreover, mostly all patients with IMM will develop Arnold-Chiari II malformation affecting hindbrain, with non-communicating hydrocephalus, which requires ventriculo-peritoneal shunting. Although mortality of IMM was low in the perinatal period, its long-term neurologic morbidity may be fatal, and up to 30% of patients may die before adulthood [57–60].

At the moment, the compared outcomes of pre-natal versus post-natal repair of IMM showed that; although prenatal surgery has an increased risk of preterm delivery, pre-natal repair had significantly better outcomes than the post-natal repair. Pre-natal repair for IMM decrease the risk of death and subsequent needs for shunting (nearly at age of 12 months). Also, pre-natal repair improves scores of mental and motor function (at 30 months). However, pre-natal repair was associated with an increased risk of preterm delivery and uterine dehiscence at labor. Therefore, the potential benefits of pre-natal repair must be balanced against the risks of

### *Principles of Fetal Surgery DOI: http://dx.doi.org/10.5772/intechopen.85883*

*Pediatric Surgery, Flowcharts and Clinical Algorithms*

• Bipolar cautery/harmonic scalpel division

• RFA of acardiac/acephalic cord insertion

hydrops fetalis, 50% mortality

• Fetoscopic ligation

*6.1.3 Selective fetal reduction*

30 days was 80% [46–50].

**6.2 Lower urinary tract obstruction (LUTO)**

• Open hysterotomy/delivery

• Thermal/laser coagulation

Fetal Surgery

Normal twin much like donor twin in TTTS with R/O high output heart failure,

In addition to TTTS, other serious problem that can affect monochorionic twin pregnancies, includes severe intrauterine growth restriction, structural anomalies, twin anemia polycythemia sequence, and TRAP sequence, or a cardiac twinning. In some complicated monochorionic pregnancies, elective fetal reduction is recommended especially for high risk of hemodynamic compromise or intrauterine fetal death, aimed to prevent neurologic injury or demise to the co-twin. Fetal intra-cardiac potassium chloride injection is contraindicated in these pregnancies, because of risk of transmission between twins and selective termination must be performed with interruption of blood flow to the fetus. This interruption usually performed through ligation of the umbilical cord, fetoscopic laser coagulation, ultrasound-guided and bipolar cord coagulation. Selective fetal reduction was seriously indicated in complicated twin pregnancies what is TRAP sequence. In TRAP sequence, one twin is incompatible with life due to absent or rudimentary heart, as well as absence of other vital structures, as head (anencephaly). This twin usually has no placental blood supply, and it receives its blood supply directly through vascular connections from the second normal twin (acts as pump twin). Therefore, the normal twin will rapidly develop high-output heart failure, with more than 50% mortality rate. Selective fetal reduction aims to stop blood flow to incompatible with life twin, and save the life of normal (pump) twin. In the largest review from 12 fetal centers from the North American Fetal Therapy Network registry data, identified 98 patients who underwent percutaneous radio frequency ablation of a cardiac twin. In this series, the overall survival of the normal (pump) twin to

LUTO can be caused by stenosis of the urethral meatus, valves, urethral atresia, ectopic insertion of a ureter or peri-vesical tumors. Bladder shunts are effective for urine diversion, restoring amniotic fluid and thereby preventing pulmonary hypoplasia. Whether shunting effectively salvages renal function is uncertain. For that, prior accurate assessment of renal function is required. The actual anatomical cause of LUTO proved to be an important predictor. Posterior urethral valves do much better in the long run, while babies with urethral atresias or the Prune Belly phenotype do less well. At the moment, the two commonly used techniques, are percutaneous vesico-amniotic shunting, under ultrasound guide, where double pigtail stent is inserted, usually combined with amnio-infusion. The second procedure is fetal cystoscopy, where fetoscope is inserted into the fetal bladder, to diagnose the

**10**

source of obstruction and to ablate PUV. The commonly used methods to ablate the valve, includes guide wires, hydro-ablation and laser-ablation. The first open clinical fetal surgical intervention for a case of lower urinary tract obstruction (LUTO), not eligible for shunt placement. Instead, fetal ureterostomies were successfully created. There were no maternal complications, but unfortunately the fetus never produced any urine. On the other hand, main complications of shunting include; failure to insert the catheter, occlusion of the catheter, dislocation, and sometimes fistula formation. In order to conclude and evaluate the results of in-utero VAS, and its longterm outcomes, randomized, controlled trial, "Percutaneous vesico-amniotic shunting versus conservative management for fetal Lower Urinary Tract Obstruction" (PLUTO), was performed in the United Kingdom, Ireland, and the Netherlands from 2006 to 2012. The study performed on 31 cases (16 submitted to VAS, 15 undergo conservative treatment). Study reported that fetal cystoscopy, although it is more invasive than VAS, it has the advantage of confirming the diagnosis of PUV, and more accurate in selection of patients who will benefit from valve ablation. In other multi-centric retrospective study includes 50 cases submitted to fetal cystoscopies for treatment of LUTO, 30 fetuses were diagnosed with PUV and were treated with laser-ablation. Other 13 fetuses were diagnosed with urethral atresia, 5 fetus diagnosed with urethral stenosis, and 2 fetuses diagnosed with trisomy 18 (not treated). The results of the 54 fetuses with normal karyotype were, 32.4 weeks mean delivery gestational age, and 34.8% overall 2 years' survival. For PUV patients treated with laser-ablation, 53.6% 2 years' survival. Although 20% (6 of the 30) developed recurrence of LUTO symptoms, and further fetal procedure was performed in 10% (3 patients). Postnatal ablation of PUV was needed in 10 of the 17 survivors. Normal renal function at 2 years of age, was achieved in 75% of infants with PUV (12 of the 16), which considered more promising than the 29% reported in the PLUTO trial with VAS. Reports up to date indicate that, minimally invasive fetal procedure (in selected cases of LUTO), can improve the survival when compared to expectant treatment. However, studies of long term renal function are less encouraging [51–56].
