Holoprosencephaly: antenatal and postnatal diagnosis and outcome

The objectives of this study are to ascertain the clinical outcome and overall survival of holoprosencephaly (HPE) patients diagnosed antenatally and postnatally, to determine the accuracy of antenatal diagnosis and to determine the role of neurosurgical intervention in HPE.

This is a retrospective review over a 10-year period.

Sixty-three patients were included in the study, 45 were diagnosed by antenatal radiological imaging and 18 were diagnosed by postnatal radiological imaging. Patient data was drawn from Temple Street Children's University Hospital (the national paediatric neurosurgery centre), the National Maternity Hospital in Holle's Street, Dublin, and Our Lady of Sick Children Hospital, Dublin.

The study was carried out through a review of antenatal and postnatal radiological imaging and reports, clinical charts, GP letters from patient follow-up and telephone conversations with parents of HPE patients.

Four patients in the antenatal diagnosis group had follow-up foetal MRI confirming HPE. Twelve in this group had radiological follow-up postnatally, and in five of these, HPE was confirmed. The remaining seven were identified as false positive. Alobar HPE constituted 55 % (21/38) of patients with 95 % mortality. Fifty-one percent had a normal karyotype. The overall survival in the antenatal diagnosis group was 13 %. In the postnatal group, 18 patients were identified, 67 % (12/18) lobar and 33 % (6/18) semilobar. Normal karyotype was found in 72 % (13/18), with an overall survival rate of 56 % (10/18). Neurosurgical intervention in both groups mainly consisted of CSF diversion in the form of ventriculoperitoneal (VP) or cystoperitoneal shunt (CP) (13/67).

Foetal MRI should be routinely performed in suspected cases of HPE, and reliance on ultrasound alone in the antenatal period may not be sufficient. In our study, there is a high early mortality noted in severe cases of HPE, while milder forms of HPE in children tend to survive beyond infancy albeit with associated complications that required neurosurgical intervention and medical management for other associated systemic anomalies.