Citation, DOI and article data
Robin sequence, also called Pierre Robin syndrome or Pierre Robin anamaloid, is a congenital condition characterized by facial abnormalities. Its etiology has no genetic base, but rather, is reliant on a sequence of events, one following the other.
Robin sequence is the preferred term rather than Pierre Robin syndrome, as most cases are not syndromic 4.
Robin sequence occurs in 1 in 8500 neonates 3.
May present with upper airway obstruction, sleep disturbance or apnea.
The primary defect is a retrognathic mandible which occurs at 7-11 weeks of gestation due to abnormal development of the first pharyngeal arch (see branchial apparatus). This prevents the tongue from descending which in turn prevents fusion of palatal shelves resulting in glossoptosis (retraction of tongue), high or U-shaped palate and airway obstruction. It is characterized by
Most cases tend to be sporadic.
A sagittal fetal facial profile may show severe micrognathia. Ancillary sonographic features include
- polyhydramnios: from impaired swallowing from micrognathia
Severe micrognathia may lead to
- obstruction of fetal swallowing: may in turn cause polyhydramnios
- airway obstruction: may, in turn, lead to postnatal hypoxia
- 1. Lachman RS, Ṭaybi H. Taybi and Lachman's radiology of syndromes, metabolic disorders, and skeletal dysplasias. Mosby Inc. (2007) ISBN:0323019315. Read it at Google Books - Find it at Amazon
- 2. Entezami M, Albig M, Knoll U et-al. Ultrasound Diagnosis of Fetal Anomalies. Thieme. (2003) ISBN:1588902129. Read it at Google Books - Find it at Amazon
- 3. Hagberg CA. Benumof's airway management. Mosby. ISBN:0323022332. Read it at Google Books - Find it at Amazon
- 4. Abramson ZR, Peacock ZS, Cohen HL et-al. Radiology of Cleft Lip and Palate: Imaging for the Prenatal Period and throughout Life. Radiographics. 2015;35 (7): 2053-2063. doi:10.1148/rg.2015150050 - Pubmed citation