Prominent basal emissary foramina in syndromic craniosynostosis: Correlation with phenotypic and molecular diagnoses

BACKGROUND AND PURPOSE: Jugular foraminal stenosis (JFS) or atresia (JFA) w ith collateral emissary veins (EV) has been documented in syndromic cranios ynostosis. Disruption of EV during surgery can produce massive hemorrhage. Our purpose was to describe the prevalence of prominent basal emissary fora mina (EF), which transmit enlarged EV, in syndromic craniosynostosis. Our f indings were correlated with phenotypic and molecular diagnoses. METHODS: We reviewed the medical records and imaging examinations of 33 pat ients with syndromic craniosynostosis and known fibroblast growth factor re ceptor (FGFR) mutations. All patients underwent CT and 14 MR imaging. The c ranial base was assessed for size of occipitomastoid EF and jugular foramin a (JF). Vascular imaging studies were available from 12 patients. A control group (n = 76) was used to establish normal size criteria for JF and EF, RESULTS: Phenotypic classification included Crouzon syndrome (n = 10), crou zonoid features with acanthosis nigricans (n = 3), Apert syndrome (n = 10), Pfeiffer syndrome (n = 4), and clinically unclassifiable bilateral coronal synostosis (n = 6), EF greater than or equal to 3 mm in diameter and JFS o r JFA mere identified in 23 patients with various molecular diagnoses. Vasc ular imaging in patients with JFS or JFA and enlarged EF revealed atresia o r stenosis,of the jugular veins and enlarged basal EV. JFA was seen in all patients with the FGFR3 mutation with crouzonoid features and acanthosis ni gricans. Four patients had prominent FF without JFS, Six patients had norma l JF and lacked enlarged EF, CONCLUSION: Enlarged basal EF are common in syndromic craniosynostosis and are usually associated with JFS or JFA, Bilateral basilar venous atresia is most common in patients with the FGFR3 ala391glu mutation and crouzonoid f eatures with acanthosis nigricans, but may be found in patients with FGFR2 mutations. Skull base vascular imaging should be obtained in patients with syndromic craniosynostosis with enlarged EF.