Implementation Process and Evolution of a Laparotomy-Assisted 2-Port Fetoscopic Spina Bifida Closure Program.

INTRODUCTION: Prenatal closure of open spina bifida via open fetal surgery improves neurologic outcomes for infants in selected pregnancies. Fetoscopic techniques that are minimally invasive to the uterus aim to provide equivalent fetal benefits while minimizing maternal morbidities, but the optimal technique is undetermined. We describe the development, evolution, and feasibility of the laparotomy-assisted 2-port fetoscopic technique for prenatal closure of fetal spina bifida in a newly established program. METHODS: We conducted a retrospective cohort study of women consented for laparotomy-assisted fetoscopic closure of isolated fetal spina bifida. Inclusion and exclusion criteria followed the Management of Myelomeningocele Study (MOMS). Team preparation involved observation at the originating center, protocol development, ancillary staff training, and surgical rehearsal using patient-matched models through simulation prior to program implementation. The primary outcome was the ability to complete the repair fetoscopically. Secondary maternal and fetal outcomes to assess performance of the technique were collected prospectively. RESULTS: Of 57 women screened, 19 (33%) consented for laparotomy-assisted 2-port fetoscopy between February 2017 and December 2019. Fetoscopic closure was completed in 84% (16/19) cases. Over time, the technique was modified from a single- to a multilayer closure. In utero hindbrain herniation improved in 86% (12/14) of undelivered patients at 6 weeks postoperatively. Spontaneous rupture of membranes occurred in 31% (5/16) of fetoscopic cases. For completed cases, median gestational age at birth was 37 (range 27-39.6) weeks and 50% (8/16) of women delivered at term. Vaginal birth was achieved in 56% (9/16) of patients. One newborn had a cerebrospinal fluid leak that required postnatal surgical repair. CONCLUSION: Implementation of a laparotomy-assisted 2-port fetoscopic spina bifida closure program through rigorous preparation and multispecialty team training may accelerate the learning curve and demonstrates favorable obstetric and perinatal outcomes.

Wave reflections in the umbilical artery measured by Doppler ultrasound as a novel predictor of placental pathology.

BACKGROUND: The umbilical artery (UA) Doppler pulsatility index is used clinically to detect elevated feto-placental vascular resistance. However, this metric is confounded by variation in fetal cardiac function and is only moderately predictive of placental pathology. Our group developed a novel ultrasound methodology that measures wave reflections in the UA, thereby isolating a component of the Doppler signal that is specific to the placenta. The present study examined whether wave reflections in the UA are predictive of placental vascular pathology. METHODS: Standard clinical Doppler ultrasound of the UAs was performed in 241 pregnant women. Of these, 40 women met narrowly defined preset criteria for the control group, 36 had maternal vascular malperfusion (MVM) and 16 had fetal vascular malperfusion (FVM). Using a computational procedure, the Doppler waveforms were decomposed into a pair of forward and backward propagating waves. FINDINGS: Compared to controls, wave reflections were significantly elevated in women with either MVM (p<0.0001) or FVM pathology (p = 0.02). In contrast, the umbilical and uterine artery pulsatility indices were only elevated in the MVM group (p<0.0001) and there were no differences between women with FVM and the controls. INTERPRETATION: The measurement of wave reflections in the UA, combined with standard clinical ultrasound parameters, has the potential to improve the diagnostic performance of UA Doppler to detect placental vascular pathology. Identifying women with FVM pathology is particularly challenging prenatally and future investigations will determine if women at risk of this specific placental disease could benefit from this novel diagnostic technique.

Single-Center Outcome of Fetoscopic Tracheal Balloon Occlusion for Severe Congenital Diaphragmatic Hernia.

OBJECTIVE: To assess feasibility and maternal and infant outcome after fetoscopic tracheal balloon occlusion in patients with severe congenital diaphragmatic hernia. METHODS: We conducted a prospective cohort study of fetuses with congenital diaphragmatic hernia and observed/expected lung/head ratio less than 30%. Eligible women had planned fetoscopic tracheal balloon occlusion at 26 0/7-29 6/7 weeks of gestation and balloon removal 4-6 weeks later. Standardized prenatal and postnatal care was at a single institution. Fetoscopic tracheal balloon occlusion details, lung growth, obstetric complications, birth outcome, and infant outcome details until discharge were evaluated. RESULTS: Of 57 women screened, 14 (25%) were enrolled between 2015 and 2019. The congenital diaphragmatic hernia was left in 12 (86%); the pre-fetoscopic tracheal balloon occlusion observed/expected lung/head ratio was 23.2% (range 15.8-29.0%). At a median gestational age of 28 5/7 weeks (range 27 3/7-29 6/7), fetoscopic tracheal balloon occlusion was successful in all cases, and balloons remained in situ. Removal was elective in 10 (71%) patients, by ultrasound-guided needle puncture in eight (57%), and occurred at a median of 33 4/7 weeks of gestation (range 32 1/7-34 4/7; median occlusion 34 days, range 17-44). The post-fetoscopic tracheal balloon occlusion observed/expected lung/head ratio increased to a median of 62.8% (44.0-108) and fell to a median of 46.6% (range 30-92) after balloon removal (all Mann Whitney U, P<.003). For prevention of preterm birth, all patients received vaginal progesterone; 11 (79%) required additional tocolytics, three (21%) had vaginal pessary placement for cervical shortening, and five (36%) had amnioreduction for polyhydramnios. Median gestational age at birth was 39 2/7 weeks (range 33 6/7-39 4/7), with term birth in eight (57%) patients. Twelve (86%) neonates required high-frequency ventilation, and seven (50%) required extracorporeal membrane oxygenation for a median of 7 days (range 3-19). All neonates needed patch repair. Neonatal survival was 93% (n=13, 95% CI 49-100%), and survival to hospital discharge was 86% (n=12, 95% CI 44-100%). CONCLUSION: Fetoscopic tracheal balloon occlusion for severe congenital diaphragmatic hernia was feasible in our single-center setting, with few obstetric complications and favorable infant outcome. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov, NCT02710968.

The Relationship between the Fetal Volume-Corrected Renal Artery Pulsatility Index and Amniotic Fluid Volume.

INTRODUCTION: To evaluate if the volume-corrected renal artery pulsatility index (vcRA-PI) is more closely related to the amniotic fluid level than the uncorrected or the gestational age (GA)-adjusted RA-PI. METHODS: RA-PI and kidney volume were measured in low- and high-risk pregnancies at 17-38 weeks. Fetal anomalies associated with nonrenal causes of abnormal amniotic fluid volume were excluded. The vcRA-PI was calculated by dividing the RA-PI by the renal volume. The RA-PI was adjusted for GA, to obtain the GA-adjusted RA-PI. The uncorrected, GA-adjusted, and the vcRA-PI were related to the amniotic fluid level using nonparametric tests and receiver operating characteristic (ROC) curve analyses. RESULTS: 146 examinations from 59 pregnancies were reviewed. Of these, 16 had oligo- and 15 had polyhydramnios. A higher vcRA-PI was associated with oligohydramnios (OR 2.54, 95% CI 1.67-3.86, p < 0.001), while the uncorrected RA-PI and GA-adjusted RA-PI were not able to predict oligohydramnios. ROC curve analysis showed a high predictive accuracy of the vcRA-PI for oligohydramnios (AUC 0.84, 95% CI 0.72-0.94). On the other hand, the uncorrected RA-PI and GA-adjusted RA-PI significantly predicted polyhydramnios (p = 0.04 and 0.02, respectively), while the vcRA-PI did not. CONCLUSION: The vcRA-PI is superior to the uncorrected and the GA-adjusted RA-PI in predicting oligohydramnios.

Aortic isthmus shunt dynamics in normal and complicated monochorionic pregnancies.

OBJECTIVE: To study fetal aortic isthmus (AoI) shunt dynamics in monochorionic (MC) twins. METHODS: Normal and complicated MC pregnancies were prospectively enrolled. The relationship of isthmus flow index (IFI) with Doppler parameters of umbilical artery (UA), descending aorta, middle cerebral artery, and ductus venosus and with left and right ventricular cardiac output and stroke volume was studied. RESULTS: The IFI was obtained in 180 examinations from 48 pregnancies (24 twin-twin transfusion syndrome, TTTS; 4 selective intrauterine growth restriction, sIUGR; 12 TTTS + sIUGR; and 8 uncomplicated). Median gestational age was 20.9 weeks. AoI diastolic flow was reversed in three cases. UA pulsatility index (PI) and ductus venosus-PI z-scores were negatively correlated with the IFI (rs -0.40 and -0.26, respectively, p < 0.001). Regression analysis identified only UA-PI as a determinant of the IFI (p < 0.001). The IFI was significantly correlated with left ventricular cardiac output and stroke volume. It did not differ between TTTS donors and recipients. sIUGR fetuses had significantly lower IFI compared with normal-grown counterparts (p < 0.001). CONCLUSION: In MC gestations, AoI shunting is predominantly determined by placental flow resistance, while cerebral impedance and volume status have no impact. In MC twins, the relationship between AoI flow and outcome deserves further study in the setting of sIUGR. © 2017 John Wiley & Sons, Ltd.

First trimester diagnosis of holoprosencephaly secondary to a ring chromosome 7.

Holoprosencephaly (HPE) is a developmental defect in humans in which the forebrain fails to completely separate into two hemispheres. We describe a 12 3/7-week-old fetus found on ultrasound evaluation to have features consistent with HPE, including a single anterior ventricle, fused thalami, and a flattened profile. Cytogenetic analysis of chorionic villi revealed a ring chromosome 7 [r(7)]. This uncommon finding has been associated with growth delay, microcephaly, and dermatologic abnormalities. However, both the clinical features and the extent of cytogenetic imbalance of chromosome 7 are variable, and few reported cases of r(7) have been molecularly studied. To our knowledge, this is the first report of a prenatally identified r(7), molecularly characterized using array comparative genomic hybridization.

Prenatal diagnosis of a paraurethral cyst.

Paraurethral cysts arising from Skene's gland are a rare cause of urogenital masses in the neonate. We report the case of a pelvic mass noted at the vaginal introitus on prenatal ultrasound that following delivery was found to be a paraurethral cyst. On prenatal ultrasound, there was no evidence of involvement of the urinary, gastrointestinal, or upper genital tract. Serial ultrasounds demonstrated slight enlargement of the cyst without other changes. The patient delivered at 33 weeks and postnatal evaluation demonstrated a paraurethral cyst. The cyst was managed expectantly and drained spontaneously on the second day of life with complete resolution.