2017-18 HSC Section 3 Green Book

ing the natural blink reflex of the eyelids, the bony prominence of the eye socket surrounding the globe, and the rigidity of the globe sclera. 10 Interestingly, Kreidel et al. demonstrated that the incidence of “significant intraocular sequelae” was decreased in patients who had severe orbital trauma (29.4%) as compared with those with mild (41.2%) or moderate (59.5%) injuries. 11 They suggested that the orbit maintains a protective mecha- nism and prevents ocular injury in severe maxillofacial traumas. Orbit fractures are managed by a multitude of spe- cialties, including otolaryngology, ophthalmology, plastic surgery, trauma surgery, and oral surgery. Each of these specialties has its own expertise, and a surgeon’s train- ing often influences their management of maxillofacial trauma. Weymuller presented specialists from ophthal- mology, otolaryngology, and plastic surgery with a clini- cal scenario regarding the treatment of Lefort III fractures with acute vision loss in one eye and normal vision in the other eye. 12 Weymuller found that the majority of ophthalmologic surgeons would defer surgical intervention in hopes of vision preservation in the “only seeing eye,” whereas the majority of plastic surgeons would proceed with surgical correction to improve facial aesthetics in a similar patient. Otolaryngologists were split in their management. This dissimilarity in surgical decision making highlights a difference in the under- standing of ocular injury and indicates that different surgical specialists have various goals that define suc- cessful patient outcomes. The specific aim of this study is to identify high- risk patients who may have ocular injury upon present- ing with maxillofacial trauma and an orbit fracture. It is the author’s opinion that any patient who sustains max- illofacial trauma with an associated orbit fracture requires a comprehensive evaluation by an ophthalmolo- gist to assess for globe injury. However, this is not possi- ble at many medical institutions, and certainly not at the time of initial presentation. Therefore, surgeons with nonophthalmologic backgrounds need to be able to iden- tify patients at high risk for ocular injury. At minimum, these high risk patients need a comprehensive ophthal- mologic evaluation because ocular injury has been asso- ciated with fractures of the orbit in roughly one-quarter of all maxillofacial trauma patients. 13 Recognizing that not all surgeons who manage maxillofacial trauma are trained in ophthalmology, it would be beneficial to estab- lish clinical clues that might suggest an underlying ocu- lar injury. By interpreting clues, such as mechanism of

TABLE IV. Incidence of Ocular Injury Associated With CT Anatomic Fracture Patterns.

No. Subjects With Ocular With Ocular Injury (%)

CT Fracture Location

No. Subjects

Isolated Single Wall Only

41

13 (31.7%)

Medial

15

6 (40.0%)

Floor

19

4 (21.1%) 2 (50.0%)

Lateral

4

Roof

3

1 (33.3%)

Multiwall Orbit Only

9

4 (44.4%)

Involved Other Facial Bones

229

60 (26.2%)

Nasal/NOE

40

11 (27.5%)

Frontal

13 56

0 (00.0%)

ZMC

17 (30.4%)

Multiple panfacial bones

119

32 (26.9%)

279

77

NOE 5 naso-orbital-ethmoid; ZMC 5 zygomaticomaxillary complex.

nasal/NOE fractures, 30.4% (17 of 56) of ZMC fractures, and 26.9% (32 of 119) of panfacial fractures. Ocular injury was not identified in any of the 13 subjects with orbit fractures combined with frontal bone fractures. Statistical analysis using a chi-square test demonstrated no association among fracture patterns and ocular injury ( P 5 0.3968). Furthermore, there was no statistically significant association between individual isolated wall fractures or orbit fractures that involved other facial bones and ocular injury using a Fisher exact test ( P 5 0.500 and 0.1595, respectively) Depth of fracture penetration within the orbit was also investigated independently. Complete radiographic data was available for comparison in 209 subjects in this group. Orbit fracture depth was classified into three types: anterior (type I), intermediate (type II), and poste- rior (type III). This data is reported in Table V. Eight subjects had type I (anterior) fractures, 78 had type II (intermediate) fractures, and 123 subjects had type III (posterior) fractures. Ocular injury was associated with 25% (2 of 8) of type I fractures, 15.4% (12 of 78) of type II fractures, and 38.2% (47 of 123) of type III fractures. A statistically significant association between depth of fracture and ocular injury was demonstrated using a chi-square analysis ( P 5 0.0024). DISCUSSION Hippocrates described the association of maxillofa- cial trauma with vision loss more than 2,000 years ago. 8,9 Fortunately, direct ocular injury associated with maxillofacial trauma is rare. When it does occur, damage to the eye varies from mild injuries (i.e., subconjunctival hemorrhage and corneal abrasion) to severe injuries (i.e., traumatic enucleation and globe rupture). MacKin- non demonstrated a 0.8% severe visual impairment or blindness in their review of 2,516 patients with maxillo- facial trauma. 10 They hypothesized that this is because the eye possesses several protective mechanisms, includ-

TABLE V. Incidence of Ocular Injury Associated With Depth of Orbit Fracture.

No. Subjects With Ocular Injury

Orbital Depth of Fracture

No. Subjects

Type I (anterior)

8

2 (25.0%)

Type II (intermediate)

78

12 (15.4%)

Type III (posterior)

123

47 (38.2%)

209

61

Laryngoscope 126: February 2016

Andrews et al.: Ocular Injury and Orbit Fractures

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