Vesicoamniotic shunting for fetal megacystis in the first trimester with a Somatex® intrauterine shunt

Pearls and Pitfalls of First-Trimester US Screening and Prenatal Testing: A Pictorial Review

First-trimester US is imperative in evaluation of early pregnancy to confirm pregnancy location and number and gestational age. The 2024 Society of Radiologists in Ultrasound consensus conference established a first-trimester lexicon to highlight the importance of clear and concise language, which is incorporated and featured by the authors. With improved technologies and understanding of fetal development, first-trimester anatomic studies, between 11 weeks and 13 weeks 6 days gestation, are becoming more frequently used. While not a replacement for the second-trimester anatomic study, systematic evaluation of fetal anatomy at this early gestational age allows detection of 40%-70% of anomalies, whether structural or related to aneuploidy. All patients, regardless of age or baseline risk, should be offered screening and diagnostic testing for chromosomal abnormalities. A variety of prenatal screening approaches are available, each with strengths and limitations. Noninvasive prenatal testing with detection of fetal cell-free DNA can be performed in the first trimester and is the most sensitive and specific screening for the common fetal aneuploidies, but is not equivalent to diagnostic testing. Alternatively, serum analytes for maternal biomarkers in conjunction with nuchal translucency (NT) measurement can be used to calculate a risk estimate for common trisomies. Increased NT is the most common abnormality seen in the first trimester. Positive screening results, increased NT, or other anomaly at US should prompt genetic counseling and be confirmed with diagnostic testing (chorionic villus sampling or amniocentesis). Early detection of aneuploidy and structural anomalies allows counseling and informs decisions for pregnancy management. ©RSNA, 2025 Supplemental material is available for this article.

Prenatal diagnosis and postnatal outcomes of congenital kidney and urinary tract anomalies: results from a tertiary center

BACKGROUND

This study aimed to investigate the prenatal features, genetic findings, and perinatal outcomes of fetuses with congenital anomalies of the kidney and urinary tract (CAKUT), with a particular focus on associations with additional structural or chromosomal abnormalities.

METHODS

A retrospective cohort analysis was conducted on 277 fetuses diagnosed with CAKUT between December 2020 and December 2024 at a tertiary center. Data on anomaly subtypes, associated findings, genetic testing, pregnancy outcomes, and postnatal follow-up were evaluated. Logistic regression was used to identify predictors of termination.

RESULTS

Urinary tract dilatation was the most frequent anomaly (28.2%), followed by multicystic dysplastic kidney (11.6%) and bilateral renal agenesis (11.2%). Extrarenal anomalies were present in 33.9% of fetuses, primarily involving the CNS. Genetic testing was performed in 48.4%; chromosomal abnormalities were found in 17.3%, most commonly trisomy 21 (5.8%). Termination was significantly associated with early diagnosis (adjusted OR = 0.82; p < 0.001), oligohydramnios (OR = 4.94; p < 0.001), CNS (OR = 3.74; p = 0.001), and cardiac anomalies (OR = 4.21; p = 0.002). Neonatal death occurred in 29.2% of cases, and mortality was higher in non-isolated anomalies (60% vs. 32.9%, p < 0.001).

CONCLUSIONS

Fetuses with CAKUT, particularly those with early diagnosis or coexisting anomalies, carry a higher risk of adverse outcomes. Prenatal detection, coupled with comprehensive genetic and structural evaluation, is essential for informed counseling and postnatal planning.

Intrauterine Therapy

Since the first intrauterine interventions were carried out in the 1970 s under what today would be considered basic conditions, the range of prenatal interventions has steadily expanded, as has the frequency with which these interventions are carried out at specialized centers. Although most of these procedures are minimally invasive, they are invariably associated with considerable risks for the fetus and, depending on the surgical method, also for the expectant mother. For this reason, most centers worldwide limit themselves to interventions for fetal diseases which, if untreated, have a fatal course or experience a significant deterioration in the postnatal prognosis during the course of intrauterine development. This is all the more significant as only a small proportion of prenatal interventions have been successfully investigated in controlled clinical trials. The only exceptions are laser therapy for feto-fetal transfusion syndrome, intrauterine closure of spina bifida, and tracheal occlusion for diaphragmatic hernia with severe pulmonary hypoplasia. This article is intended to provide an overview of the fetal conditions that are candidates for intrauterine therapy and of the evidence for the individual interventions.

Intermediate outcomes of children (4-10 years) with postnatally preserved renal function after vesico-amniotic shunt insertion for lower urinary tract obstruction (LUTO)

PURPOSE

The purpose of this retrospective study was to examine the intermediate outcomes and renal development of children (four to ten years) who had undergone prenatal vesico-amniotic shunt insertion (VAS) for lower urinary tract obstruction (LUTO), and later demonstrated preserved kidney function as neonates.

PATIENTS & METHODS

Of 63 fetuses that underwent VAS for LUTO, 47 survived both the pregnancy and the neonatal period. Twenty-four of them were born with preserved renal function as defined by normal laboratory values for creatine, urea, and/or GFR. Twenty of them (83.3 %) were available for our study. We analyzed their pediatric general, surgical, urological, and radiological medical records with a particular emphasize on renal function.

RESULTS

All children of the cohort are still alive. None of the pediatric study subjects have required renal replacement therapy after four to ten years of follow-up. In 90 % of the cases, renal function as defined by laboratory values for creatine, urea, and/or GFR remained preserved. Only two children (10 %) demonstrated impaired renal function.

CONCLUSION

The findings of our retrospective study suggest that when normal laboratory values for creatine, urea, and/or GFR are observed in the neonatal period following prenatal VAS for LUTO, these parameters will likely remain normal in most patients for the first four to ten years of their life. Confirming our previously published novel management strategy, the highest preservation rates can be achieved when after early detection of LUTO, VAS can be performed prior to the completion of 16 weeks of gestation.

Postnatal surgical complications in lower urinary tract obstruction following fetal vesico- amniotic shunting

PURPOSE

Fetal lower urinary tract obstruction (LUTO) is a rare congenital disease associated with high morbidity and mortality due to pulmonary hypoplasia and renal insufficiency. Fetal management includes early vesicoamniotic shunting (VAS), a technique that has evolved in recent years to preserve kidney function. Previous publications have focused on intrauterine shunt complications, such as dislocation and preterm premature rupture of membranes (PPROM). In our study we aimed to assess postnatal shunt related complications that became obvious after birth.

MATERIALS AND METHODS

We describe our preliminary experience with 25 fetuses who underwent VAS with a Somatex® shunt as well as postnatal shunt removal at two experienced centers for fetal medicine. The intrauterine course, underlying pathology, postnatal outcome and details on shunt explantation and related complications were assessed. The data were retrospectively analysed in relation to the intrauterine course, underlying pathology, further malformations, and perioperative characteristics with a focus on the complication spectrum and type of intervention.

RESULTS

Twenty-five fetuses underwent VAS at a median of 17 weeks. Two newborns were excluded because they died within the first 24 hours of life secondary to fulminant lung hypoplasia. In ten (43%) newborns, shunt removal was performed under local anaesthesia. In 13 (57%) neonates, the shunt was explanted surgically, and five (22%) of these operations were defined as complex.

CONCLUSION

Intrauterine VAS with a Somatex® shunt is feasible, and in the majority of cases, shunt explantation can be easily performed after birth. However, the umbrellas may cause intraabdominal tissue damage, peritoneal adhesions or skin defects, and early surgical management of VAS associated complications might be necessary.

Favorable outcome after fetal swallowing of a Somatex® intrauterine shunt

This report describes the ingestion of a dislodged Somatex Intrauterine Stent by the fetus. At 35 weeks one shunt was visualized in the fetal stomach, suggesting that the fetus had swallowed it. The shunt kept its position in the stomach until the last follow up scan at 37 weeks. At 38 weeks the patient went into spontaneous labor and vaginally delivered a boy weighting 3590 g. The first chest X-ray on the day of birth demonstrated the dislodged shunt in the duodenum while the other shunt drained the left kidney. The mother started breastfeeding. The x-ray on the second day of life was made after removal of the second shunt and the creation of a nephrostoma and demonstrated the dislodged shunt in the ileum. On the third day of life the shunt was found in the neonate's stool. The neonate was dismissed on day 7 with antibiotic prophylaxis. To our best knowledge this is the first report of an intrauterine ingestion of a Somatex Intrauterine Stent. It demonstrates that in the intrauterine period the shunt remains in the stomach and starts to pass the bowel after birth, probably prompted by breastfeeding. In our case the shunt was eventually excreted without any damage to the digestive system.

A new spectrum of neonatal urethral pathologies in the era of early vesicoamniotic shunting?

PURPOSE

Intrauterine vesicoamniotic shunting (VAS) was shown to affect survival of male fetuses with megacystis in suspected lower urinary tract obstruction (LUTO). Data on postnatal management are largely lacking. We aim to describe the pathologies diagnosed in children born after vesicoamniotic shunt placement in early pregnancy for megacystis.

METHODS

All newborns with previous intrauterine VAS treated in our institution were analyzed retrospectively. We evaluated the clinical spectrum of urethral pathologies. We also compared patients who received a shunt before the 17th gestational week with those who received it later.

RESULTS

Between 2014 and 2023, 26 patients (all male) with a history of VAS for suspected LUTO were treated in our institution postnatally. Five fetuses with dislocated shunts underwent re-implantation in utero. Overall, premature birth before the 38th week of gestation was observed in 14 patients. Seven patients received a Harrison® shunt whereas 19 received a Somatex® shunt. Twelve patients required surgical shunt removal under general anesthesia due to shunt migration/embedding. Posterior urethral valves were found in 10/26 patients, 10/26 patients showed a urethral hypoplasia [Fig. 1] and two patients had urethral duplications. In two patients, we identified a prune belly syndrome. One patient had posterior and anterior urethral valves. One patient had a high grade bilateral vesicoureteral reflux without LUTO. The 11 patients shunted early (before 17GW) showed a trend towards a higher proportion of urethral hypoplasia in the early shunt group (54% vs. 26%) without statistical significance.

CONCLUSION

In our observation, patients treated with VAS had a noticeable high proportion of complex urethral pathologies such as urethral hypoplasia. These data should be taken into consideration for prenatal counselling of parents and planning of postnatal management.

Advancement of 3D printing technology for the development of a training model in US-guided vesicoamniotic shunting for early LUTO therapy

INTRODUCTION

Prenatal lower urinary tract obstruction (LUTO) is a rare and challenging condition with potential severe morbidity and mortality. Prenatal shunting methods, specifically vesicoamniotic shunting (VAS) and fetal cystoscopy, aim to manage this condition. However, comprehensive education and training are hindered by the rarity of LUTO. To address this gap, we present a low-cost 3D-printed ultrasound training model for VAS in LUTO fetuses. The aim of the study was to evaluate ultrasound and haptic fidelity of the model.

MATERIAL AND METHODS

Ultrasound images of three LUTO fetuses at 12-14 weeks were utilized to create detailed 3D-printed models. Fusion360TM software generated stereo-lithography files, and the Formlabs Form3® printer, using Flexible 80A resin, produced the models. A simulation box mimicking uterine conditions and fetal anatomy was developed for testing. Ultrasound assessments determined model accuracy, and expert evaluations gauged fidelity for VAS placement.

RESULTS

The 3D-printed model accurately replicated LUTO fetal anatomy, demonstrating structural integrity and realistic sonographic and haptic feedback during 20 punctures. Macroscopic visualization confirmed the model's durability and authenticity.

DISCUSSION

This innovative 3D-printed model addresses the scarcity of LUTO cases and the lack of realistic training tools. Simulation models enhance skills, providing a controlled learning environment that bridges theoretical knowledge and clinical application, potentially improving patient outcomes.

CONCLUSIONS

The 3D-printed training model for VAS in LUTO represents a significant advancement in surgical education, offering realistic anatomical simulation and tactile feedback. Future studies should assess its effectiveness in enhancing surgical skills and impacting patient outcomes in clinical practice.

Single-center outcome analysis of 46 fetuses with megacystis after intrauterine vesico-amniotic shunting with the Somatex®intrauterine shunt

OBJECTIVES

To assess the spectrum of underlying pathologies, the intrauterine course and postnatal outcome of 46 fetuses with megacystis that underwent intrauterine vesico-amniotic shunting (VAS) with the Somatex® shunt in a single center.

METHODS

Retrospective analysis of 46 fetuses with megacystis that underwent VAS either up to 14 + 0 weeks (early VAS), between 14 + 1 and 17 + 0 weeks (intermediate VAS) or after 17 + 0 weeks of gestation (late VAS) in a single tertiary referral center. Intrauterine course, underlying pathology and postnatal outcome were assessed and correlated with the underlying pathology and gestational age at first VAS.

RESULTS

46 fetuses underwent VAS, 41 (89%) were male and 5 (11%) were female. 28 (61%) fetuses had isolated and 18 (39%) had complex megacystis with either aneuploidy (n = 1), anorectal malformations (n = 6), cloacal malformations (n = 3), congenital anomalies overlapping with VACTER association (n = 6) or Megacystis-Microcolon Intestinal-Hypoperistalsis Syndrome (MMIHS) (n = 2). The sonographic 'keyhole sign' significantly predicted isolated megacystis (p < 0.001). 7 pregnancies were terminated, 4 babies died in the neonatal period, 1 baby died at the age of 2.5 months and 34 (74%) infants survived until last follow-up. After exclusion of the terminated pregnancies, intention-to-treat survival rate was 87%. Mean follow-up period was 24 months (range 1-72). The underlying pathology was highly variable and included posterior urethral valve (46%), hypoplastic or atretic urethra (35%), MMIHS or prune belly syndrome (10%) and primary vesico-ureteral reflux (2%). In 7% no pathology could be detected postnatally. No sonographic marker was identified to predict the underlying pathology prenatally. 14 fetuses underwent early, 24 intermediate and 8 late VAS. In the early VAS subgroup, amnion infusion prior to VAS was significantly less often necessary (7%), shunt complications were significantly less common (29%) and immediate kidney replacement therapy postnatally became less often necessary (0%). In contrast, preterm delivery ≤ 32 + 0 weeks was more common (30%) and survival rate was lower (70%) after early VAS compared to intermediate or late VAS. Overall, 90% of liveborn babies had sufficient kidney function without need for kidney replacement therapy until last follow-up, and 95% had sufficient pulmonary function without need for mechanical respiratory support. 18% of babies with complex megacystis suffered from additional health restrictions due to their major concomitant malformations.

CONCLUSIONS

Our data suggest that VAS is feasible from the first trimester onward. Early intervention has the potential to preserve neonatal kidney function in the majority of cases and enables neonatal survival in up to 87% of cases. Despite successful fetal intervention, parents should be aware of the potential of mid- or long-term kidney failure and of additional health impairments due to concomitant extra-renal anomalies that cannot be excluded at time of intervention.

Postnatal surgical treatment and complications following intrauterine vesicoamniotic shunting with the SOMATEX® intrauterine shunt. A single center experience

INTRODUCTION

Intrauterine vesicoamniotic shunting (VAS) using a Somatex® shunt was shown to significantly affect survival of male fetuses with megacystis in suspected lower urinary tract obstruction (LUTO) [Figure 1]. Data on postnatal surgical management and complications are largely lacking.

OBJECTIVE

To describe the postnatal management of patients with prenatal VAS for megacystitis in suspected severe LUTO.

STUDY DESIGN

All male newborns with previous intrauterine VAS using a Somatex® shunt treated in our institution were retrospectively analyzed. We evaluated the spectrum of urethral pathologies and postnatal surgical management, especially focusing on shunt removal.

RESULTS

Between 2016 and 2022, 17 patients (all male) were treated postnatally in our institution after VAS for suspected severe LUTO. Five fetuses with dislocated shunts underwent re-implantation in utero. Overall, premature birth before the 38th week of gestation was observed in eight patients (8/17). Seven shunts could be removed without further anesthesia as a bedside procedure. Ten patients required surgical shunt removal under general anesthesia due to migration (59%). Laparoscopic shunt extraction was performed in 8/10 cases. Most frequently, dislocated shunts were located incorporated in the detrusor in eight cases and the removal required a bladder suture in 2/8 patients. In one case, the shunt was removed from the abdominal wall and in one case from the intestine wall [Figure 2]. Posterior urethral valves were found in 8/17 patients, 6/17 patients showed a urethral atresia and one patient had urethral duplication. In two patients, we identified a high grade bilateral vesicoureteral reflux without LUTO.

CONCLUSION

In our observation, more than half of the newborns with megacystis in suspected LUTO require a shunt removal surgery after early VAS using a Somatex® shunt. Urethral atresia may be found more frequently in these patients. These data should be taken into consideration for prenatal counselling of parents and planning of postnatal management.

Observed to expected lung area to head circumference ratio (O/E LHR) in fetuses with congenital anomalies of the kidney and urinary tract (CAKUT): assessment and evaluation as predictive factor for acute postnatal outcome-a single center study

Introduction

To assess the observed to expected lung area to head circumference ratio (O/E LHR) in fetuses with congenital anomalies of the kidney and urinary tract (CAKUT) and to explore its value as a potential predictive factor for postnatal outcome.

Methods

A retrospective single-center study was conducted on pregnancies complicated by CAKUT between 2007 and 2018. The lung-to-head ratio (LHR) was calculated for each fetus by two independent observers. Correlations between O/E LHR and various perinatal outcome factors were assessed with Spearman's rank correlation. Furthermore, nominal logistic regression was performed to assess O/E LHR as predictive factor for respiratory distress in newborn.

Results

Of 64 pregnancies complicated by CAKUT, 23 were terminated. In the 41 cases of continuation of pregnancy, newborn presenting respiratory distress with need for respiratory support in the delivery room showed earlier gestational age at onset of amniotic fluid abnormalities and at birth. Although median O/E LHR and median single deepest pocket (SDP) of amniotic fluid were significantly smaller in newborn that did develop respiratory distress with need of respiratory support in the delivery room, neither O/E LHR nor SDP were accurate predictors for the development of respiratory distress.

Conclusions

Our data show that O/E LHR alone cannot serve as a predictive marker for fetal outcome in pregnancies complicated by CAKUT, though it might still be a helpful parameter together with detailed renal ultrasound evaluation, onset of amniotic fluid abnormality and SDP, particularly in its extreme values.

Lifesaving Treatments for the Tiniest Patients-A Narrative Description of Old and New Minimally Invasive Approaches in the Arena of Fetal Surgery

Fetal surgery has become a lifesaving reality for hundreds of fetuses each year. The development of a formidable spectrum of safe and effective minimally invasive techniques for fetal interventions since the early 1990s until today has led to an increasing acceptance of novel procedures by both patients and health care providers. From his vast personal experience of more than 20 years as one of the pioneers at the forefront of clinical minimally invasive fetal surgery, the author describes and comments on old and new minimally invasive approaches, highlighting their lifesaving or quality-of-life-improving potential. He provides easy-to-use practical information on how to perform partial amniotic carbon dioxide insufflation (PACI), how to assess lung function in fetuses with pulmonary hypoplasia, how to deal with giant CPAMS, how to insert shunts into fetuses with LUTO and hydrothorax when conventional devices are not available, and how to resuscitate a fetus during fetal cardiac intervention. Furthermore, the author proposes a curriculum for future fetal surgeons, solicits for the centralization of patients, for adequate maternal counseling, for adequate pain management and adequate hygienic conditions during interventions, and last but not least for starting the process of academic recognition of the matured field as an independent specialty. These steps will allow more affected expectant women and their unborn children to gain access to modern minimally invasive fetal surgery and therapy. The opportunity to treat more patients at dedicated centers will also result in more opportunities for the research of rare diseases and conditions, promising even better pre- and postnatal care in the future.

Vesicoamniotic Shunting before 17 + 0 Weeks in Fetuses with Lower Urinary Tract Obstruction (LUTO): Comparison of Somatex vs. Harrison Shunt Systems

(1) Background: The aim of this study was to compare perinatal outcomes and complication rates of vesicoamniotic shunting (VAS) before 17 + 0 weeks in isolated LUTO (lower urinary tract obstruction) with the Somatex® intrauterine shunt vs. the Harrison fetal bladder shunt. (2) Methods: This is a retrospective cohort study in two tertiary fetal medicine centers. From 2004−2014, the Harrison fetal bladder shunt was used, and from late 2014−2017, the Somatex shunt. Obstetrics and pediatric charts were reviewed for complications, course of pregnancy, perinatal outcome, and postnatal renal function. (3) Results: Twenty-four fetuses underwent VAS with a Harrison (H) shunt and 33 fetuses with a Somatex (S) shunt. Live birth rates and survival to last follow-up were significantly higher in the Somatex group, at 84.8% and 81.8%, respectively, vs. 50% and 33.3% in the Harrison group (p = 0.007 and p < 0.001). The dislocation rate in the Somatex group (36.4%) was significantly lower than in the Harrison group (87.5%) (p < 0.001). The median time to dislocation was significantly different, at 20.6 days (H) vs. 73.9 days (S) (p = 0.002), as was gestational age at dislocation (17 (H) vs. 25 (S) weeks, p < 0.001). Renal function was normal in early childhood in 51% (S) vs. 29% (H) (p = 0.11). (4) Conclusions: VAS before 17 + 0 weeks gestational age with a Somatex shunt improves perinatal survival significantly and might even have a positive effect on renal function, probably due to the lower dislocation rates. A normal amount of amniotic fluid in the third trimester was the best predictor of normal renal function in early childhood.

Vesico-amniotic shunt insertion prior to the completion of 16 weeks results in improved preservation of renal function in surviving fetuses with isolated severe lower urinary tract obstruction (LUTO)

PURPOSE

The purpose of this retrospective cohort study was to compare the outcome of human fetuses with isolated severe lower urinary tract obstructions (LUTO) that were first treated before the completion of 16 weeks of gestation to fetuses first treated later in gestation.

PATIENTS AND METHODS

Vesicoamniotic shunt insertion (VAS) was performed in 63 subsequent fetuses with LUTO between 12 + 5 and 30 + 3 weeks. The fetuses were analyzed in three groups: Group-I-fetuses underwent their first intervention until the completion of 16 weeks, Group-II-fetuses were first treated between 16 + 1 and 24 + 0 weeks and Group-III-fetuses beyond 24 + 1 weeks. Renal and pulmonary outcome parameters and complicating factors were assessed.

RESULTS

- All mothers tolerated the procedures well. Overall fetal survival was 47 of 63 (75%). The mean age at delivery of survivors was 35 weeks. 68% of Group-I-fetuses, 77% of group-II-fetuses, and 100% of group-III-fetuses survived beyond postnatal hospital discharge. Amongst the survivors the chance for normal renal function was higher for group I with 79% (15/19) compared to first fetal intervention after the completion of 16 weeks with 32% (9/28, p = 0.003, OR = 7.9 [2.0, 30.8] 95% CI). Clinically relevant pulmonary hypoplasia was observed in 11% of Group-I-, 27% of Group-II-, and 20% of Group-III-fetuses.

CONCLUSIONS

Early intervention in fetal LUTO before the completion of 16 weeks may achieve a higher rate of normal renal and pulmonary function in survivors than treatment beyond that point in time. This observation is important for the future management of this challenging patient population.

Development and in-vitro characterization of a novel fetal vesicoamniotic shunt - the Vortex Shunt

OBJECTIVES

To develop and test a novel vesicoamniotic shunt (VAS) to treat fetal lower urinary tract obstruction (LUTO), decrease dislodgement and optimize shunt deployment in-vitro.

METHODS

VAS design objectives included: 1) robust and atraumatic fixation elements, 2) kink resistant conduit to adjust to fetal movement and growth, 3) one-way pressure valve to facilitate bladder cycling, and 4) echogenic deployment visualization aids. The force to dislodge the novel Vortex shunt was compared with existing commercially available shunts in a bench-top porcine bladder model. Sonographic echogenicity was evaluated with ultrasound-guided deployment, and the shunt valve pressure measured.

RESULTS

A prototype novel Vortex shunt was developed using braided nitinol "umbrella-type" ends with a kink-resistant stem incorporating an internal one-way valve. The peak force required to dislodge the Vortex shunt was significantly higher than commercially available shunts (p<0.01). Shunt deployment in the bench-top model was easily confirmed with ultrasound guidance and the brisk decompression of the inflated porcine bladder thereafter. In-vitro valve gauge pressure testing mirrored bladder pressures in human LUTO cases.

CONCLUSION

In-vitro testing shows that the Vortex shunt may improve deployment, sonographic visualization, kink resistance, and dynamic size adjustment. Validation in preclinical animal models are warranted and currently underway. This article is protected by copyright. All rights reserved.

Fetal therapy of LUTO (lower urinary tract obstruction) - a follow-up observational study

PURPOSE

Fetal megacystis (MC) can be severe and is mainly caused by fetal lower urinary tract obstruction (LUTO). Mortality of fetal LUTO can be high as a result of pulmonary hypoplasia and/or (chronic) renal insufficiency. Several technical procedures for vesicoamniotic shunting (VAS) were developed to improve fetal MC outcomes.

MATERIAL AND METHODS

We present the outcome of nine fetuses with MC who received VAS in the prenatal period (14 + 6 to 27 + 6 weeks GA) using the Somatex^® intrauterine shunt system. MC was defined as an increased longitudinal measurement of the bladder >15 mm. The median follow-up time after birth was 18 months.

RESULTS

Eight Fetuses had uncomplicated VAS intervention. One case developed PPROM 24 h after VAS leading to abortion. Pregnancy was later terminated in further two cases. All six live-born infants received intensive care treatment. Invasive-mechanical ventilation was necessary in one case who died 24 h post-partum of severe cardiac depression. Five infants who survived the follow-up time developed chronic renal insufficiency (CRI), with one infant developing end-stage renal failure requiring peritoneal dialysis.

CONCLUSION

Overall, 5 of 9 LUTO fetuses (55%) undergoing VAS with the Somatex^® intrauterine shunt system showed long-term survival beyond the neonatal period of 28 d (5/9; 55%) with varying morbidity.

Postnatal Management in Congenital Lower Urinary Tract Obstruction With and Without Prenatal Vesicoamniotic Shunt

Purpose: Congenital lower urinary tract obstruction (cLUTO) includes a heterogeneous group of conditions caused by a functional or mechanical outlet obstruction. Early vesicoamniotic shunting (VAS) possibly reduces the burden of renal impairment. Postpartum, pediatric urologists are confronted with neonates who have a shunt in place and a potentially impassable urethra with a narrow caliber. Early management of these patients can be challenging. Here, we would like to share the approach we have developed over time. Materials and Methods: We conducted a single-center retrospective analysis from 2016 to 2020 and included all patients diagnosed with cLUTO. Data focusing on time point and type of intervention was collected. Furthermore, patients with temporary diversion via a percutaneous VAS were selected for a more detailed review. Results: In total, 71 cases of cLUTO were identified during the study period. Within this group, 31 neonates received postnatal management and surgical intervention in our center. VAS was performed in 55% of these cases (N = 17). The postnatal treatment varied between transurethral or suprapubic catheterization and early Blocksom vesicostomy. In five infants with VAS, the urinary drainage was secured through the existing VAS by inserting a gastric tube (N = 1) or a 4.8 Fr JJ-stent (N = 4). To our knowledge, this is the first report of a stent-in-stent scheme, which can remain indwelling until the definite treatment. Conclusion: Having a secure urine drainage through a VAS allows the often premature infant to grow until definite surgery can be performed. This avoids placing a vesicostomy, which requires anesthesia.