Extending the Pallister-Hall syndrome to include other central nervous system malformations.

Hall-Pallister syndrome is defined by specific facial anomalies, post axial polydactyly, imperforate anus, and brain anomalies including a rare diencephalic mass, hypothalamic hamartoblastoma. In this article, two patients are described with the usual features of Hall-Pallister syndrome, including diencephalic anomalies, but without hamartoblastomas. These patients may suggest an appropriate extension of the definition of the Hall-Pallister syndrome.