Prenatal magnetic resonance imaging (MRI) findings of a foregut duplication cyst of the tongue: value of real-time MRI evaluation of the fetal swallowing mechanism.

Foregut duplication cysts of the oral cavity or lingual choristomas have a potential risk of airway obstruction. Two cases are reported that were initially detected by screening sonography. Further imaging with both static and real-time cine magnetic resonance imaging confirmed the lingual origin, relationship of the mass to fluid-filled spaces within the oral cavity, motion of the mass with the tongue during fetal swallowing, and airway patency. The additional information provided by magnetic resonance imaging aided in planning delivery and obviated the need for an ex utero intrapartum treatment procedure because airway patency was confirmed in both cases.