Abstract
Purpose: :
A computed tomography scan (CT) is the current gold standard for the diagnosis of orbital fractures. Given the recent heightened awareness of radiation exposure associated with CT imaging, we reviewed the yield of orbital CT scans in patients with orbital trauma presenting to a tertiary care eye center.
Methods: :
Retrospective case series. All consecutive orbital CT scans between 2008 and 2010 that were performed after orbital trauma were reviewed. Demographics, patient symptoms, and physical exam findings were noted.
Results: :
The charts of 107 patients with CT scans for orbit trauma were reviewed. 50 patients (47%) had radiographic evidence of a fracture (average age 30±13.8 yrs, 88% male, 48% Caucasian, 20% Hispanic). 57 patients (53%) had no fracture on CT scan (average age 43±20.7 yrs, 61% males, 54% Caucasian, 23% Hispanic). The following signs and symptoms were associated with fracture: 88% with complaints of binocular diplopia, 39% of patients without diplopia had a fracture (p<0.001), 92% of patients with extraocular motility restrictions in any gaze, 32% of patients with full motility (p<0.001), 73% with commotio retinae, 42% of those without commotio retinae (p<0.05), 73% of those patients with peri-orbital hypoesthesia, 44% of those without complaints of hypoesthesia (p=0.06), 50% of those patients with 2 mm or greater difference in Hertel exophthalmometry between affected and unaffected eyes, 46% of those less than or equal to 2mm difference. Of the 50 patients with fractures, three patients required surgical repair.
Conclusions: :
We have established that in patients with commotio retinae, binocular diplopia, and restriction of extraocular movements, performing an orbital CT scan after trauma is likely to reveal radiographic evidence of an orbital fracture. This imaging is required for surgical planning. Only three of the 107 patients who underwent a CT scan underwent surgical repair, perhaps refining clinical features that are associated with a fracture could change the current practice pattern of using a CT scan for all orbital trauma patients. These results will form the basis of a prospective trial comparing the utility of an orbit CT scan to a facial X-ray, which poses a lower radiation risk, as a screening image for trauma.
Keywords: orbit • imaging/image analysis: clinical