Expanded Möbius syndrome.

A woman presented at 33 weeks gestation with reduced fetal movements and a nonreactive nonstress test. Fetal ultrasound examination revealed a peculiar unilateral arm tremor. At emergency cesarean section, performed for fetal indications, a 1,672-gm male infant was delivered requiring intubation for feeble respiratory effort. After delivery the neonate was transiently hypertonic and later hypotonic. Continuing ventilatory support at minimal settings was necessary. The work-up for aneuploidy, metabolic disorders, and infection was negative. The infant died after being removed from ventilatory support on day 22. Postmortem examination revealed extensive bilateral brain gliosis and mineralization without evidence of inflammation, partial absence of cranial nerve nuclei III-XI, and a total absence of cranial nerve roots VI-XI. Together these finding are compatible with a diagnosis of expanded Möbius syndrome.