A Case Report of Aplasia of the epiglottis and the hyoid bone in a Pierre Robin Sequence Patient, an underreported association?

Abstract

Introduction: Abnormalities of the epiglottis and hyoid bone have been described in association with Pierre Robin Sequence (PRS). Embryologically, the epiglottis stems between the third and fourth branchial arches, while the hyoid bone develops from the second and third arches. The body of the hyoid bone completes its development by 4 months of age, and in fact can be seen on imaging in the majority of children after 9 months of age. Case: We present a case of an 18-year-old male known for PRS, who underwent a tracheostomy within a week of life and multiple airway evaluations since. Complete absence of his epiglottis was noted early on. Numerous computed tomographies (CTs) preformed during his lifetime with three-dimensional reconstruction of facial bones; however, only reported bony anomalies of the mandible and zygomatic arches. In a retrospective review of imaging by his surgeons and the center's radiologist, the body of the hyoid bone was found to be clearly absent from the earliest CT at 2 years of age. His greater cornua; meanwhile, remain present leading into soft tissue and potentially cystic content in the midline. Discussion: These anomalies bring up the question of an underreported association within PRS patients considering their close embryological origins. Aplasia of the epiglottis is well reported independently, but there have been very few studies on hyoid anomalies in this population. A larger series is needed to evaluate the frequency as well as potential clinical impact of these abnormalities in unison within the PRS population.

Keywords

• Pierre robin sequence
• PRS
• Epiglottis aplasia
• Hyoid bone
• Hyoid anomaly