Oral abstract presentation times

Purpose

Orbital fracture patients often have motility restriction and diplopia. This study evaluates extraocular muscle imaging features in patients with orbit fractures.

---

Methods

Cross-sectional cohort study of patients referred to a single institution for acute orbital fracture evaluation from January 2021 to March 2024. Exclusion criteria included ruptured globe, bilateral orbital fractures, or inability to perform voluntary eye movements. Motility was assessed by video recordings and measured using duction angles, with significant limitation defined as ≥10º in one direction. Recti muscle cross sectional areas (CSAs) of fractured and control sides were calculated via computed tomography (CT) scans in the coronal plane 6-8 mm posterior to the globe-optic nerve junction. Muscle enlargement was defined as ≥67% difference in muscle CSA between the two sides.

---

Results

123 patients were included (median age 41 [IQR: 29,62]; 75.5% male). The most common fracture site was orbital floor (n=99, 80.4%) then medial wall (n=55, 44.7%). 49.6% (n=61) had more than 1 wall fractured. 59 (48.0%) patients had motility restriction in at least one direction versus 64 (52.0%) with no restriction. Supraduction limitation was most common (n=39, 66.1%). Comparing those with motility restriction to those without, there were no differences in age, sex, fracture type, or number of walls fractured (p≥0.10). Patients with motility restriction were significantly more likely to have muscle enlargement (OR 8.1, 95% CI 2.15, 45.70, p<0.001). The enlarged muscle was typically adjacent to the fractured wall (81%) with motility restriction typically occurring in the direction away from the fracture (63%). In 40%, restriction was noted both towards and away from the enlarged muscle. Three (2.5 %) patients had muscle enlargement without motility restriction.

---

Conclusion

Patients presenting with muscle enlargement after orbit fracture are 8 times more likely to have motility restriction. However, muscle enlargement does not explain all motility restriction, as more than half of patients with restriction did not demonstrate muscle enlargement on CT.

---

Additional Authors

First name	Last name	Base Hospital / Institution
Jessica	Tran	University of California, Los Angeles
Arshia	Arjomandi	University of California, Los Angeles
Angela	Oh	University of California, Los Angeles
Katherine	Lucarelli	University of California, Los Angeles
Nathan	Pirakitikulr	University of California, Los Angeles
Javier	Moreno-Alemán	University of California, Los Angeles
Frank	Mei	University of California, Los Angeles
Robert	Goldberg	University of California, Los Angeles
Daniel	Rootman	University of California, Los Angeles

↑ Back to top