Division of Ultrasound, Department of Obstetrics and Gynecology, University of Miami School of Medicine, Miami, FL 33136

Synonyms: Acrocephalosyndactyly[i]

Definition: Condition that consists of Irregular Craniosynostosis, Midfacial Hypoplasia, Syndactyly, and Broad Distal Phalanx of Thumb and Big Toe.1

Etiology: Autosomal dominant. Seems to be related to mutations in the fibroblast growth factor receptor 2 gene (FGFR2). Different mutations in the same gene cause Crouzon Syndrome as well as Pfeiffer Syndrome. Apert is related to a mutation on the area that maps chromosome 10q25-10q26. The recurrence risk for the affected individual is 50%. If parents are unaffected, the recurrence risk is negligible.1

Ultrasound diagnosis: brachycephaly and acrocephaly, high forehead, flat occiput, Craniosynostosis usually involving the coronal sutures, flat face, and hypertelorism. Other ultrasound findings that are present are agenesis of the corpus callosum, mild ventriculomegaly and fusion of the cervical vertebrae at the level of C5-C6. In the extremities we can find Syndactyly "mitten hand†(osseous and cutaneous) usually involving the second, third, and fourth fingers. There is a broad thumb and hallux.

Minor findings could be found in the cardiovascular system including tetralogy of Fallot, and genitourinary anomalies such as cystic kidneys, hydronephrosis and crytorchidism.2

Case:

25 y/o Primigravida at 35 weeks of gestation sent for an ultrasound because the mother had some anomalies of the face and the fingers and the uterus was size greater than dates.

Frontal bossing (2D and 3D views).

The posterior fossa:

The hands:

Differential diagnosis: includes dysostoses with cranial and facial involvement such as different forms of Craniosynostosis, Crouzon (craniofacial dysostoses), Pfeiffer (Acrocephalosyndactyly type c) and Carpenters (acrocephalopolysyndactyly).3

Prognosis: several degrees of mental retardation have been reported. Surgery for craniosynostosis is indicated when there is evidence of an increase in intracranial pressure. Early neurosurgical treatment does not prevent mental retardation. Upper airway obstruction can be seen when there is reduction in the size of the nasopharynx. 1,2

Obstetrical Management: the option of pregnancy termination should be offered to parents prior to viability. If pregnancy is carried passed viability, delivery should occur in a tertiary center. Securing the airway might be crucial at the time of delivery. Cesarean section is usually recommended with the use of the EXIT procedure (ex uterus intrapartum treatment), which provides time for laryngoscopy, bronchoscopy, and even tracheostomy. Early delivery should only be reserved for the situation when there is ultrasound evidence of increase in intracraneal pressure. 2,4

References:

1. Jones KL. Smith’s Recognizable Patterns of Human Malformation. 5^th Ed. Philadelphia, WB Saunders, 1997, 418-19.
2. Benacerraf BR. Ultrasound of Fetal Syndromes. New York, Churchill Livingstone, 1998, 200-02.
3. Romero R, Pilu G, Jeanty P, Ghidini A, Hobbins JC. Prenatal Diagnosis of Congenital Anomalies. Connecticut, Appleton and Lange, 1988, 370-73.
4. Bianchi DW, Crombleholme TM, D’Alton ME. Fetology, Diagnosis and Management of the Fetal Patient. New York, McGraw-Hill, 2000, 835-36.