Our preliminary data suggest that HA gel fillers with differing production technologies show distinct spread and distribution patterns in the periocular tissues on HRUS examination.

Despite variability in the HA gel distribution and long-term conformational changes on ultrasound examination, HA injection may be an effective and minimally invasive method to improve upper eyelid position for patients with mild eyelid retraction in both the active and inactive stages of TED.

High-resolution ultrasound allows in vivo study of HA injection behavior. HA adopts different morphology within the tissue depending on the density and compliance of the tissues in the plane of injection.

There is a significant increase in the infratemporal fossa fat, nasal and orbital volume corresponding to a decrease in maxillary sinus size in chronic maxillary atelectasis. Chronic maxillary atelectasis is associated with redistribution of volume between the maxillary sinus and the surrounding infratemporal fossa, orbit and nasal cavity.