Scientific Session 26 — General/EmergencyFriday, May 5, 2017
1145. Orbital Blunt Trauma: Can CT Help in Predicting the Development of Diplopia?
Cellina M*, Oliva G. ASST Fatebenefratelli Sacco, Milan, Italy
Address correspondence to M. Cellina (email@example.com)
Objective: The management of orbital fracture, in terms of need for surgical repair and timing of surgery, is controversial. In the acute setting, ophthalmologic examination may be limited due to sedation, decreased mental status, or comorbid injuries, so orbital CT has a major role in collecting clinical data, especially in the unconscious patient. The presence of diplopia is considered the most important criteria for planning a surgical intervention. Our aim was to determine the orbital CT findings that can be used to predict the development of permanent diplopia in patients with orbital fractures.
Materials and Methods: We retrospectively evaluated orbital CT scans of all patients presented to our emergency department for blunt craniofacial trauma (n = 3400) from January 2014 to April 2016, selecting only patients with CT-demonstrated orbital fracture. The following CT variables were assessed: fracture location (medial wall, floor, lateral wall, roof, medial and floor, lateral and floor, lateral and roof, or multiple locations), fracture multifocality, bone fragments displacement, extraocular muscle thickening, muscle entrapment, muscle displacement, muscle hooking, intraconal emphysema, extraconal emphysema, intraconal hematoma, extraconal hematoma, and fat herniation. All patients underwent complete ophthalmologic evaluation and Hess-Lancaster testing to establish the presence of diplopia. After performing group comparison with a chi-square test, we derived our prediction model using logistic regression, with diplopia as the prediction and CT variables as predictors.
Results: We observed 300 patients (222 men and 78 women; mean age, 46 years; range, 4–93 years) with orbital fracture due to a blunt trauma, 46 (15.3%) with diplopia proven by the Hess Lancaster test. The CT variables with statistically significant differences between the group with diplopia and the group without diplopia were floor fracture (p = 0.014), bone fragments displacement (p = 0.001), multifocality (p = 0.005), muscle thickening (p = 0.001), muscle entrapment (p < 0.001), muscle displacement (p < 0.001), and fat herniation (p = 0.003). The CT variables with significance as predictors of diplopia were floor location (odds ratio [OR], 2.87; 95% CI, 1.22–6.73; p = 0.01), muscle thickening, muscles entrapment (OR, 10.69; 95% CI, 3.76–30.4; p < 0.001), and muscle displacement (OR, 11.51; 95% CI, 3.05–43.3; p < 0.001).
Conclusion: The development of persistent diplopia can be predicted on the basis of CT findings after an orbital trauma. Such patients should be directed toward early surgical repair to reestablish extraocular muscle function.