2017-18 HSC Section 3 Green Book

injury, basic physical exam findings, and CT radio- graphic fracture patterns, a surgeon may identify simul- taneous ocular injury and possibly delay intervention until a comprehensive evaluation by an ophthalmologist is completed. Using this concept, Al-Qurainy developed the acronym BAD ACT to be used to assess high-risk patients. 14 This system used blowout fracture, acuity problems, diplopia, amnesia, and comminuted trauma as high-risk indicators for ocular trauma. This same group later published a scoring system that indicated all patients with impaired visual acuity with a blowout or comminuted fracture, a motility abnormality, and facial fractures combined with a head injury causing amnesia required a comprehensive ophthalmologic evaluation. 15 The mechanism of injury causing maxillofacial trauma and orbit fracture is often easily obtained in a patient history. This information is the first clinical clue that a surgeon is presented with when encountering such a patient. Magarakis’ meta-analysis demonstrated that high-impact zygomatic fractures with orbital involvement were most commonly associated with blind- ness. 6 Guly et al. reviewed 4,082 patients with maxillo- facial fractures and found that 398 (9.8%) had an ocular injury, including corneal abrasion (31%), optic nerve injury (13.2%), and conjunctiva injury (12.9%). 16 This group found no difference in the incidence of ocular injury with the type or location of the facial fracture sus- tained; however, 57.3% of ocular injuries were the result of an MVA. Rosado 17 found MVA to be the most common cause of orbit fracture, and MacKinnon 10 found that MVA was most likely to cause vision impairment when compared with assault, fall, and other etiologies. Smith et al. suggested that there was a geographic bias toward MVA (47%) as the mechanism of injury in their study. 18 This study was conducted in a medium-sized city within the United States as compared to other studies con- ducted in larger metropolitan cities such as Chicago and Detroit, which demonstrated assault to be the most com- mon etiology. 18 Vaca et al. studied the mechanism of injury associated with open globe injury and found a sig- nificant increase associated with penetrating trauma. 19 Despite these published reports, a knowledge gap still exists in the literature pertaining to mechanism of injury for orbit fractures and concomitant eye injury. Not surprisingly, this study demonstrates the high- est incidence of ocular injury associated with penetrating trauma (47.6%). However, 47.6% is surprisingly low given the extreme amount of force sustained during penetrating trauma. Upon further review of this group of patients, 100% were blind when the penetrating injury occurred at the orbit itself. All patients who did not demonstrate an ocular injury associated with penetrating trauma sus- tained an injury to the lower face or midface and not to the orbit itself. These injuries transmitted a fracture that involved a nondisplaced or minimally displaced fracture of the orbit and no ocular injury. Gonul et al. demon- strated similar findings of visual outcomes among patients with similar orbitocranial projectile injuries. 20 A major aim of this study is to identify high-risk indi- viduals based on their mechanism of injury. Statistical analysis indicates that there is a significant association

between the mechanism of injury and concomitant ocular trauma. Penetrating trauma was the most likely mecha- nism of injury to cause ocular injury. Therefore, based on this study it is recommended that all individuals who sus- tain an orbit fracture as a result of penetrating trauma require an ophthalmologic consultation prior to any nonur- gent surgical procedure. Physical examination findings are another important indicator of ocular injury. There is little doubt that some- one trained in ophthalmology is more qualified to perform a comprehensive ophthalmologic examination. However, any surgeon who manages maxillofacial trauma should be qualified and comfortable documenting four key physical exam findings: visual acuity, extraocular movements, afferent pupillary defects, and chemosis 6 subconjuncti- val hemorrhage. Several studies have limitedly assessed the significance of certain physical exam findings in orbit fracture patients. Al-Qurainy et al. attempted to predict high-risk eye injury patients and found that decreased visual acuity is the best predictor with a sensitivity of 80%. 14 Petro et al. confirmed these findings by showing that 14 of 26 orbit fracture patients with ocular injury reported decreased visual acuity. 21 Gonul et al. demon- strated a poor visual prognosis was predicted for patients with a relative afferent pupillary defect positive injury. 20 The results of these three studies are supported by the data presented in this study. Individuals with either a vis- ual acuity deficit and/or an afferent pupillary defect require a comprehensive ophthalmologic evaluation as a statistically significant association with concomitant ocu- lar injury. Extraocular movement restriction still remains an important exam finding because it may indicate muscle entrapment, which is a surgical emergency and may cause vision impairment if not treated appropriately. Chemosis is also an important exam finding, especially when it is circumferential, because it may indicate a globe rupture. However, neither finding was statistically associated with ocular injury in this dataset. Fractures involving the orbit may occur in isolation or involve concomitant factures of the frontal, zygomatic, maxillary, nasal, and/or sphenoid bones. Different frac- ture locations within the orbit alone and those associated with other maxillofacial injuries indicate different vectors and degrees of force that caused the orbit fracture. Differ- ent forces and different vectors may predispose certain patients to concomitant ocular injury. Rowe and Williams suggested classifying orbital fractures as isolated orbit fractures, ZMC, and complex maxillofacial fractures. 22 However, to date no classification system has been rou- tinely utilized by surgeons who manage maxillofacial trauma and orbit fractures. The most likely reason for this is that no current classification system provides use- ful clinical information. Based on this knowledge gap in the literature, the current study tries to more precisely categorize orbit fractures based on their anatomic location on CT scan and other associated maxillofacial injuries. Commonly, orbit fractures are limited to one wall (medial, lateral, roof, or floor) or involve a combination of two or more walls without involvement of other bones. Karabekir et al. found that 50% of orbit fractures were isolated to one wall, 29% to two walls, 16% to three

Andrews et al.: Ocular Injury and Orbit Fractures

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