Congenital hernia of cord: an often misdiagnosed entity

Congenital hernia of the cord, also known as umbilical cord hernia, is an often misdiagnosed and under-reported entity, easily confused with a small omphalocele. It is different from postnatally diagnosed umbilical hernias and is believed to arise from persistent physiological mid-gut herniation. Its incidence is estimated to be 1 in 5000. Unlike an omphalocele, it is considered benign and is not linked with chromosomal anomalies. It has been loosely associated with intestinal anomalies, suggesting the need for a complete fetal anatomical ultrasound evaluation. We present a case of a fetal umbilical cord hernia diagnosed in a 28-year-old woman at 21 weeks gestation. The antenatal and intrapartum courses were uncomplicated. It was misdiagnosed postnatally as a small omphalocele, causing unwarranted anxiety in the parents. Increased awareness and knowledge of such an entity among health professionals is important to prevent unwarranted anxiety from misdiagnosis, and inadvertent bowel injury during cord clamping at delivery.

A Novel Mutation on RAF1 in Association with Fetal Findings Suggestive of Noonan Syndrome

Noonan syndrome is a multisystem genetic disorder caused by genes encoding proteins involved in the RAS-MAPK pathway. Affected fetuses have variable presentations ranging from the absence of prenatal findings to increased nuchal fold, cystic hygromas, pleural effusions, cardiac malformations, or skin edema. We describe a male fetus who had features consistent with Noonan syndrome at the time of fetal anatomic survey, including hydrops and a possible cardiac defect. Subsequent scan revealed persistent bilateral pleural effusions (with predominance of lymphocytes). After bilateral thoracoamniotic shunt placement, the fetus did well and delivered at term. Prenatal testing revealed an S650F missense mutation in the RAF1 gene, which had not previously been associated with Noonan syndrome.

Fetal mediastinal lymphangiomas

OBJECTIVE

The purpose of this series was to evaluate the prenatal sonographic findings and postnatal outcomes in 2 fetuses with mediastinal lymphangiomas.

METHODS

The fetal images were compared with postnatal imaging and surgical findings.

RESULTS

The 2 fetuses had anechoic mediastinal masses at 25 and 22 weeks, which proved to be lymphangiomas. One, located in the anterior mediastinum, also enveloped the superior vena cava, brachial plexus, phrenic nerve, larynx, and lower parts of the neck vessels and extended into the subcutaneous tissues of the anterior chest wall through an intercostal space. In the second patient, the lymphangioma appeared to be a unilocular cyst, which involved the deep tissues of the neck as well as the posterior and lateral mediastinum. Both required 2 interventions after birth.

CONCLUSIONS

Fetal mediastinal lymphangiomas appeared anechoic and sent extensions into the neck in the first case, around the superior vena cava, through the intercostal spaces to the skin, and around the brachial plexus in the second case, and deviated the trachea in both cases. In 1 case, there was also ectasia of the superior vena cava. This ability to entwine around vital structures can make it difficult to determine the extent of involvement on antenatal sonography and to remove lymphangiomas completely, and recurrence is common.

Isolated choroid plexus separation on second-trimester sonography: natural history and postnatal importance

OBJECTIVE

This study was undertaken to investigate the natural history and clinical importance of choroid plexus separation (a > or = 3 mm distance between the choroid plexus and medial wall of the lateral ventricle) as an isolated finding in the second trimester.

METHODS

This was a 5-year retrospective review of an ultrasound database, looking for singleton fetuses with a menstrual age of 16 to 26 weeks and a finding of isolated choroid plexus separation.

RESULTS

There were 78 cases available for study. The finding of choroid plexus separation was usually transient. Resolution was noted in 37% of the cases that were rescanned within 2 weeks and 71% of the cases that were rescanned more than 2 weeks after the initial diagnosis. Two abnormal karyotypes (trisomy 21 and 47,XXY) and 3 cases with abnormal development not associated with an abnormal karyotype were noted on neonatal follow-up. Cases with abnormal development were quite varied in their presentation.

CONCLUSIONS

The finding of isolated choroid plexus separation is usually temporary, resolving in most cases within 4 weeks of the initial diagnosis. Most infants with this finding have no abnormalities. The clinical implication of the lone case of trisomy 21 was limited by a major preexisting risk in this patient. The 3 cases of abnormal development had varying presentations; the causal nature of this association is not yet clear. No trends were noted between the changing choroid plexus appearance with time and abnormal neonatal outcome, but the number of abnormal cases was quite limited.