The Hard Palate Sweep: a multiplanar 2-dimensional sonographic method for the prenatal detection of cleft palate

BACKGROUND

Prenatal diagnosis of cleft palate is challenging. Numerous 2-dimensional and 3-dimensional methods have been proposed to assess the integrity of the fetal palate, yet detection rates remain relatively low. We propose the "Hard Palate Sweep," a novel 2-dimensional method that enables clear demonstration of the entire fetal palate throughout pregnancy, in a single sweep, avoiding acoustic shadows cast by surrounding bones.

OBJECTIVE

This study aimed to assess the feasibility and performance of the Hard Palate Sweep, performed throughout pregnancy.

STUDY DESIGN

This was a prospective cross-sectional study performed between 2018 and 2022 in pregnant patients referred for a routine or targeted anomaly scan between 13 and 40 weeks of gestation. The presence or absence of a cleft palate was determined using the "Hard Palate Sweep." This was compared with the postnatal palate integrity assessment. Test feasibility and performance indices, including sensitivity, specificity, and positive and negative predictive values were calculated. Offline clips were reviewed by 2 investigators for the assessment of inter- and intraoperator agreement, using Cohen's kappa formula. The study protocol was approved by the institutional ethics committee. All participating patients were informed and provided consent.

RESULTS

A total of 676 fetuses were included in the study. The Hard Palate Sweep was successfully performed in all cases, and 19 cases were determined to have a cleft palate. Of these, 13 cases were excluded because postmortem confirmation was not performed, leaving 663 cases available for analysis. Six cases determined to have a cleft palate were confirmed postnatally. In 655 of 657 cases prenatally determined to have an intact palate, this was confirmed postnatally. In the 2 remaining cases, rare forms of cleft palate were diagnosed postnatally, rendering 75% sensitivity, 100% specificity, 100% positive predictive value, and 99.7% negative predictive value for the Hard Palate Sweep (P<.001). There was complete intra- and interoperator agreement (kappa=1; P<.0001).

CONCLUSION

The Hard Palate Sweep is a feasible and accurate method for prenatally detecting a cleft palate. It was successfully performed in all attempted cases between 13 and 40 weeks of gestation. This method is reproducible, offering high sensitivity and specificity. Implemented routinely, the Hard Palate Sweep is expected to increase the prenatal detection of cleft palate.

Umbilical-portal-systemic venous shunt and intrauterine growth restriction: an inquiry from a prospective study

BACKGROUND

The investigation of the fetal umbilical-portal venous system is based on the premise that congenital anomalies of this system may be related to adverse perinatal outcomes. Several small retrospective studies have reported an association between umbilical-portal-systemic venous shunts and intrauterine growth restriction. However, the prevalence of portosystemic shunts in the fetal growth restricted population is yet to be determined.

OBJECTIVE

The aims of this study were (1) to determine the prevalence of fetal umbilical-portal-systemic venous shunts in pregnancies complicated by intrauterine growth restriction and (2) to compare the perinatal and neonatal outcomes of pregnancies with intrauterine growth restriction with and without umbilical-portal-systemic venous shunts.

STUDY DESIGN

This was a prospective, cross-sectional study of pregnancies diagnosed with intrauterine growth restriction, as defined by the Society for Maternal-Fetal Medicine intrauterine growth restriction guidelines. All participants underwent a detailed anomaly scan, supplemented with a targeted scan of the fetal portal system. Venous shunts were diagnosed using color Doppler mode. The perinatal outcomes of pregnancies with intrauterine growth restriction with and without umbilical-portal-systemic venous shunts were compared.

RESULTS

A total of 150 cases with intrauterine growth restriction were recruited. The prevalence of umbilical-portal-systemic venous shunts in our cohort was 9.3% (n=14). When compared with the control group (intrauterine growth restriction without umbilical-portal-systemic venous shunts, n=136), the study group had a significantly lower mean gestational age at the time of intrauterine growth restriction diagnosis (29.7±5.6 vs 32.47±4.6 weeks of gestation; P=.036) and an earlier gestational age at delivery (33.50±6.0 vs 36.13±2.8; P=.005). The study group had a higher rate of fetal death (21.4% vs 0.7%; P<.001) and, accordingly, a lower rate of live births (71.4% vs 95.6%; P=.001). Additional associated fetal vascular anomalies were significantly more prevalent in the study group than in the control group (35.7% vs 4.4%; P≤.001). The rate of other associated anomalies was similar. The study group had a significantly lower rate of abnormal uterine artery Doppler indices (0% vs 40.4%; P=.011) and a higher rate of abnormal ductus venosus Doppler indices (64.3% vs 23%; P=.001). There were no cases of hypertensive disorders of pregnancy in the study group, whereas the control group had an incidence of 12.5% (P=.16). Other perinatal and neonatal outcomes were comparable.

CONCLUSION

Umbilical-portal-systemic venous shunt is a relatively common finding among fetuses with growth restriction. When compared with pregnancies with intrauterine growth restriction with a normal portal system, these pregnancies complicated by intrauterine growth restriction and an umbilical-portal-systemic venous shunt are associated with a different Doppler flow pattern, an increased risk for fetal death, earlier presentation of intrauterine growth restriction, a lower gestational age at delivery, additional congenital vascular anomalies, and a lower rate of pregnancy-induced hypertensive disorders. Meticulous sonographic evaluation of the portal system should be considered in the prenatal workup of intrauterine growth restriction, as umbilical-portal-systemic venous shunts may affect perinatal outcomes.

In-utero evaluation of the fetal umbilical-portal venous system among fetuses with persistent right umbilical vein: Two-and three-dimensional ultrasonographic study

OBJECTIVE

The aim of this study was to describe the anatomy of the portal system in fetuses with persistent right umbilical vein (PRUV).

METHODS

Prospective observational study of fetuses diagnosed with PRUV. All patients underwent a comprehensive portal system anatomy scan supplemented by two-dimensional (2D) and three-dimensional (3D) color doppler modalities.

RESULTS

29 fetuses with PRUV were studied. We perceived an identical anatomical pattern in 28 fetuses. The right umbilical vein drains to the portal sinus (future right portal vein, RPV), which has a configuration of a left portal vein (LPV) in the normal left portal system, with three emerging branches: inferior (RPVi), medial (RPVm) and superior (RPVs). The RPV then courses to the left, towards the stomach to the point of the bifurcation of the main portal vein (MPV) to become the left portal vein. The LPV has an RPV configuration in a normal portal system with anterior (LPVa) and posterior (RPVp) branches. This anatomical layout mimics a mirror image of the normal anatomy of left portal system.

CONCLUSION

PRUV has unique umbilical portal venous anatomy, which is a mirror image of the normal left portal system. It can be demonstrated prenatally and serve as an additional tool for prenatal diagnosis of PRUV.

Congenital hypotonia: systematic approach for prenatal detection

OBJECTIVES

Congenital hypotonic conditions are rare and heterogeneous, and some are severely debilitating or lethal. Contrary to its prominent postnatal manifestation, the prenatal presentation of hypotonia is frequently subtle, inhibiting prenatal detection. We aimed to characterize the prenatal sonographic manifestation of congenital hypotonia throughout pregnancy, evaluate the yield of diagnostic tests and propose diagnostic models to increase its prenatal detection.

METHODS

This was a retrospective observational study of singleton pregnancies with congenital hypotonia, diagnosed either prenatally or immediately after birth, at a single tertiary center between the years 2012 and 2020. Prenatally, hypotonia was diagnosed if a fetus showed sonographic or clinical signs suggestive of hypotonia and had a confirmed underlying genetic condition, or in the absence of a known genetic abnormality if the fetus exhibited multiple prominent signs suggestive of hypotonia. Postnatally, it was diagnosed in neonates displaying reduced muscle tone leading to reduced spontaneous movement, reduced swallowing or feeding difficulty. We reviewed the medical records of pregnant patients carrying fetuses subsequently diagnosed with congenital hypotonia and assessed the yield of ultrasound scans, fetal magnetic resonance imaging, computed tomography and genetic tests. The detection rate of sonographic signs suggesting fetal hypotonia was calculated. The prevalence of non-specific signs, including polyhydramnios, persistent breech presentation, intrauterine growth restriction and maternal perception of reduced fetal movement, were compared between the study group and the local liveborn singleton population. Potential detection rates of different theoretical semiotic diagnostic models, differing in the threshold for referral for a targeted scan, were assessed based on the cohort's data.

RESULTS

The study group comprised 26 cases of congenital hypotonia, of which 10 (38.5%) were diagnosed prenatally, and the controls included 95 105 singleton live births, giving a prevalence of congenital hypotonia of 1:3658. Nuchal translucency thickness and the early anomaly scan at 13-17 weeks were normal in all 22 and 23 cases, respectively, in which this was performed. The mid-trimester scan performed at 19-25 weeks was abnormal in four of 24 (16.7%) cases. The overall prenatal detection rate of congenital hypotonic conditions in our cohort was 38.5%. Only cases which underwent a targeted scan were detected and, among the 16 cases which underwent this scan, the prenatal detection rate was 62.5% compared with 0% in pregnancies that did not undergo this scan (P = 0.003). An abnormal genetic diagnosis was obtained in 21 (80.8%) cases using the following modalities: chromosomal microarray analysis (CMA) in two (9.5%), whole-exome sequencing (WES) in 14 (66.7%) and methylation analysis in five (23.8%). CMA was abnormal in 8% (2/25) of the cases and WES detected a causative genetic mutation in 87.5% (14/16) of the cases in which these were performed. Comparison of non-specific signs in the study group with those in the local singleton population showed that hypotonic fetuses had significantly more polyhydramnios (64.0% vs 3.0%, P < 0.0001), persistent breech presentation (58.3% vs 4.2%, P < 0.0001), intrauterine growth restriction (30.8% vs 3.0%, P < 0.0001) and maternal perception of reduced fetal movement (32.0% vs 4.7%, P < 0.0001). Prenatally, the most commonly detected signs supporting a diagnosis of hypotonia were structural anomaly (62.5%, 10/16), reduced fetal movement (46.7%, 7/15), joint contractures (46.7%, 7/15) and undescended testes ≥ 30 weeks (42.9%, 3/7 males). Proposed diagnostic strategies that involved performing a targeted scan for a single non-specific ultrasound sign or two such signs, and then carrying out a comprehensive genetic evaluation for any additional sign, offered theoretical detection rates in our cohort of 88.5% and 57.7%, respectively.

CONCLUSIONS

Congenital hypotonic conditions are rare and infrequently detected prenatally. Sonographic signs are visible from the late second trimester. A targeted scan increases prenatal detection significantly. Comprehensive genetic testing, especially WES, is the cornerstone of diagnosis in congenital hypotonia. Theoretical diagnostic models which may increase prenatal detection are provided. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Early Fetal Corpus Callosum: Demonstrating Normal Growth and Detecting Pathologies in Early Pregnancy

BACKGROUND AND PURPOSE

A malformed corpus callosum carries a risk for abnormal neurodevelopment. The advent of high-frequency transducers offers the opportunity to assess corpus callosum development in early pregnancy. The aim of the study was to construct a reference chart of the fetal corpus callosum length on ultrasound between 13 and 19 weeks of gestation and to prospectively examine growth patterns in pathologic cases.

MATERIALS AND METHODS

We performed a prospective cross-sectional study between 2020 and 2022 in well-dated, low-risk, singleton pregnancies between 13 and 19 weeks of gestation. A standardized image was obtained in the midsagittal plane. Imaging criteria were used as a confirmation of the early corpus callosum. Measurements were taken by 4 trained sonographers. Intra- and interobserver variability was assessed. Corpus callosum length in centiles were calculated for each gestational week.

RESULTS

One hundred eighty-seven fetuses were included in the study. All cases met inclusion criteria. At 13 weeks of gestation, the margins of the early corpus callosum were sufficiently clear to be measured in 80% (20/25) of fetuses. A cubic polynomial regression model best described the correlation between corpus length and gestational age. The correlation coefficient (r 2) was 0.929 (P < .001). Intra- and interobserver variability had high interclass correlation coefficients (>0.99). Presented is the earliest published case of agenesis of corpus callosum and a case of dysgenetic corpus callosum in Rubinstein-Taybi syndrome.

CONCLUSIONS

Provided is a nomogram of the early fetal corpus callosum. Applying imaging criteria helped to identify a case of complete agenesis of the corpus callosum as early as 14 weeks.

The prenatal detection of distal tracheoesophageal fistulas in fetuses diagnosed with esophageal atresia

BACKGROUND

Esophageal atresia is a major anomaly of varying severity. The complexity of surgical correction depends on the presence of a distal fistula.

OBJECTIVE

This study aimed to determine the feasibility and accuracy of prenatal ultrasound detection of the distal fistula in fetuses diagnosed with esophageal atresia.

STUDY DESIGN

This was an observational study conducted at a single tertiary care center between 2019 and 2021. Included were pregnant patients carrying a fetus prenatally diagnosed with esophageal atresia that was confirmed postnatally during corrective surgery or at postmortem autopsy. During the scan, the performing investigator determined the presence or absence of a distal fistula by scanning the location of the lower esophagus during fetal breathing. Cases in which the lower esophagus was observed distending with amniotic fluid during breathing were deemed "fistula present," and the remaining cases "fistula absent." Test feasibility and performance indices, including sensitivity, specificity, and positive and negative predictive value were calculated. The offline clips and images were reviewed by 2 investigators for the assessment of interoperator agreement using Cohen's Kappa formula.

RESULTS

Included were 16 fetuses with esophageal atresia scanned between 2019 and 2021. All fetuses were successfully scanned with sufficient resolution of the area of interest during at least 3 cycles of breathing. It took a median of 8.5 minutes to determine the presence or absence of a distal fistula. The feasibility of the test was 100% (16/16). The test's sensitivity, specificity, and positive and negative predictive values were 80% (95% confidence interval, 55-100), 100% (95% confidence interval, 60-100), 100% (95% confidence interval, 65-100), and 75% (95% confidence interval, 45-100), respectively. The Cohen's Kappa for interoperator agreement was calculated to be 1, P<.001, corresponding to a "perfect" level of agreement.

CONCLUSION

Distal fistulas in esophageal atresia can be demonstrated prenatally by targeted scanning using appropriate technique. The method provided is feasible, reproducible, and has excellent performance indices. This novel technique and observations may improve the prenatal diagnosis and counseling of esophageal atresia.

[PERINEAL TEARS THAT INVOLVE THE ANAL SPHINCTER - IS IT AN UNPREVENTABLE OBSTETRIC PROBLEM AND WHAT ARE ITS REPRECUSSIONS?]

Perineal tears that involve the anal sphincter, especially those which are occult, are common in cases of vaginal delivery or instrumental deliveries. Parturients who experience such types of perineal tears may suffer from flatus or fecal incontinence and also fistula to various surrounding organs. There is no consensus in the relevant medical literature regarding the risk factors for the development of these tears, as contradictive results are presented in various relevant studies. Traditional methods for perineal protection, executed by midwives, such as perineal massage with oil, have also failed to be proven as an effective measure for that purpose. The only theme on which there appears to be a consensus is the fact that protective episiotomy is not helpful in protecting the perineum during vaginal delivery. The inability to predict which parturient will have a perineal tear that involves the anal sphincter, as well as the lack of predictive measures to avoid their occurrence, drive more and more women to demand and receive cesarean section by maternal request, which is accepted by most obstetricians nowadays.