Craniosynostosis and childbirth

Antenatal Ultrasound Imaging for Analysis of Human Craniosynostosis

The cranial sutures can be imaged sonographically in the fetus as early as the end of the first trimester; however, fetal position and maternal body habitus can present significant challenges to clear visualization. Antenatal identification of craniosynostosis is important for delivery planning, and there are a number of available ultrasound techniques and imaging signs to assist with accurate diagnosis of both single suture craniosynostosis and syndromic multisutural fusions.

The Normal Fetal Cephalic Index in the Second and Third Trimesters of Pregnancy

The cephalic index (CI) is used in the evaluation of individuals with craniosynostosis. There is little agreement as to the normal range and stability of the CI during the fetal period, partly due to limited literature. We sought to determine the range, distribution and stability of the fetal CI in the second half of pregnancy. We also aimed to identify any relationship to delivery complications such as obstructed labor and malpresentation.The fetal head circumference, biparietal diameter (BPD) and occipitofrontal diameter (OFD) measurements were obtained from standard ultrasound images. Each of 4304 fetuses had measurements taken at morphology scan performed between 17 and 22 weeks' gestation, and at growth scanning at 28 to 33 weeks' gestation. The cephalic index was calculated using the formula: CI = BPD/OFD × 100. The distribution of the CI at both scans is very close to a normal distribution. The mean CI at 17 to 22 weeks was 75.9 (SD, 3.7); the mean CI at 28 to 33 weeks was 77.8 (SD, 3.5). The mean change in CI was 1.9 (SD, 4.28), which is not statistically significantly different from zero (t = 0.656, P = 0.512, 95% confidence interval). No relationship was found between the CI in normal fetuses and delivery complications. There is a wide variation in the change in CI in the third trimester. A value below the normal range in the third trimester or a progressive reduction in CI during the latter half of pregnancy should provoke detailed scanning of the fetal cranial sutures to check for craniosynostosis.

Sonographic indicators of isolated fetal sagittal craniosynostosis during pregnancy

INTRODUCTION

The antenatal diagnosis of sagittal craniosynostosis can be challenging, but there are several published papers describing a traumatic outcome to both the affected fetus and the mother during delivery of a scaphocephalic child. The antenatal imaging from affected children was collected along with the mother's obstetric history. The aim of this study was to identify antenatal ultrasound features that may assist the diagnosis of sagittal synostosis before birth, to enable appropriate delivery planning and avoid both maternal and fetal trauma during birth.

METHODS

Antenatal ultrasound scans in both the second and third trimesters were traced for 36 children with sagittal synostosis. The initially diagnostic CT scans were also sourced. A delivery history was collected from the hospital case notes where available.

RESULTS

The affected group showed a statistically significant reduction in cephalic index during the second half of pregnancy compared with the normal population which became slightly more brachycephalic (P = 0.001). Regression analysis showed an average reduction in cephalic index of 0.57 units per month. There was also a much higher rate of malpresentation and surgical deliveries in the affected group than the normal population. There was a relationship between sagittal craniosynostosis and breech presentation and an associated higher rate of surgical deliveries.

CONCLUSION

It is possible to detect sagittal synostosis in the third trimester of pregnancy which may assist with delivery planning.

Perinatal features and rate of cesarean section in newborns with non-syndromic sagittal synostosis

PURPOSE

The purpose of this study was to evaluate perinatal features and the rate of cesarean section in children with non-syndromic sagittal synostosis and to compare these with the official statistics.

METHODS

The birth data of 36 consecutive children (25 boys) operated on using cranial vault remodeling because of primary sagittal synostosis were analyzed retrospectively from hospital records. The children were born between 2007 and 2011, and the surgery was performed before the age of 1 year. The official statistics of all Finnish newborns from the year 2010 (n = 61 371) were used as a reference. Chi-square and Fisher's exact tests were used in statistical analyses.

RESULTS

The average gestational age of the newborns with sagittal synostosis was 39.8 weeks (reference 39.7 weeks). The average birth weight was 3565.8 g (3540 g) for boys and 3197.2 g (3427 g) for girls, and the average lengths at birth are 51 cm (50.4 cm) and 49.4 cm (49.6 cm), respectively. The average head circumference was 36 cm for both sexes (35.2 and 34.6 cm for reference boys and girls). The mean age of mothers was 30.5 years (30.1 years). The rate of cesarean section was significantly increased 30.5 % (reference 16.6 %), and the rate of suction cup delivery was increased 13.9 % (9 %). In addition, a prolonged or difficult delivery was reported in three childbirths.

CONCLUSION

Newborns with non-syndromic sagittal synostosis appear to be of average birth size and gestational age. The incidences of perinatal complications and cesarean sections were increased with problems occurring in more than half of the childbirths.

Incidence of perinatal complications in children with premature craniosynostosis

AIMS

To study the incidence of perinatal complications in children diagnosed with premature craniosynostosis and their mothers.

METHODS

Questionnaires were sent to all women (n=220) who delivered a child diagnosed either pre- or postnatally with craniosynostosis and treated at the University Hospital of Innsbruck, Austria between January 1, 1990 and October 10, 2007. The incidence of various complications in the group of children with craniosynostosis was compared with data from the Birth Registry of Tyrol, which served as a comparison population in this study (n=57,317).

RESULTS

A total of 46.4% of the questionnaires were returned (n=102). Children diagnosed with craniosynostosis showed a significantly higher rate of fetal malpresentations at birth [P<0.001; OR 2.38 (CI 1.53-3.70)] compared to the general population. In particular, the rate of abnormal cephalic [P<0.001; OR 3.42 (CI 2.03-5.76)] and breech presentations [P=0.01; OR 2.39 (CI 1.27-4.49)] was significantly increased. In 10% of all neonates the Apgar score (P=0.001) as well as the pH-value (P<0.001) was found to be at least one category lower than in the comparison population.

CONCLUSIONS

Children diagnosed with craniosynostosis have a significantly higher rate of numerous birth complications compared to the overall births documented at the Birth Registry of Tyrol.