Unusual Combined Orbital Roof and Orbital Floor Fractures in A Pediatric Patient.

Orbital fractures in children have characteristically different patterns than those in skeletally mature adults.[1,2] The lack of pneumatization of the frontal sinus and the prominence of the frontal bone in small children render this population susceptible to anterior cranial base fractures involving the orbital roof. Blow-in fractures of the orbital roof decrease the intra-orbital volume and can be associated with visual changes, intracranial injuries, and, if untreated, pulsatile exophthalmos from a growing skull fracture or encephaloceles. Orbital floor injuries are also pathophysiologically different in small children, due to the tendency of the orbital floor to greenstick fracture, resulting in “trapdoor” injuries with associated entrapment of the inferior rectus. In contrast to their observed frequency in adults, orbital floor blow-out fractures are rare in small children. Coon et al. reported on a large series of pediatric patients with orbital roof fractures.[2] In their cohort of 85 patients with orbital roof injuries, 25% had associated medial wall fractures, 16% had associated lateral wall fractures, and 13% had associated zygomaticomaxillary complex fractures.[2] Of the orbital roof fractures, nearly 60% were inferiorly displaced, or were “blow-in” fractures. Within their series, no patient required repair of both the orbital floor and orbital roof.

A 3-year-old patient was transferred to our craniofacial center for evaluation of injuries related to a 20-foot fall while hiking. Visual examination was notable for diplopia with superior and inferior gaze and vertical ocular dystopia. No other visual disturbances or evidence of globe injury were identified. Craniofacial imaging was notable for a displaced left-sided orbital floor blowout fracture (2.5 cm2) with associated soft tissue herniation and a concomitant left-sided orbital roof blow-in fracture (4.0 cm2), as well as a small left-sided epidural hemorrhage not requiring emergent evacuation (Fig. 1A).

Fig. 1.

Coronal computed tomography views demonstrating a displaced orbital roof blow-in fracture and large orbital floor blowout fracture pre-operatively (A) and following operative repair (B).

Open reduction of the fractures was performed via a transcranial approach to the orbital roof and a transconjunctival approach to the orbital floor. The orbital roof fracture was reduced into anatomic alignment. The herniated soft tissue contents associated with the orbital floor injury were reduced and the defect was reconstructed using a porous-polyethylene implant impregnated with titanium mesh (Fig. 1B). The dura was inspected and did not require repair. Post-operative recovery was uneventful, with improved globe position and vision both on craniofacial team evaluation and on formal ophthalmology evaluation.

Patterns of orbital injury in young children remain markedly different than those seen in skeletally mature teenagers and adults. As eyes rapidly grow in infancy, the bony orbit completes half of its postnatal growth by the age of 2 years.[3] This case demonstrates an atypical combined injury of the internal orbital framework. Mechanistically, this pattern is unusual because of the synchronous displacement of the orbital roof and floor. Previously described patterns of combined orbital roof and floor injuries demonstrate divergent displacement of the roof and floor, typically with mechanisms that transfer energy directly into the orbit, often resulting in globe injury or rupture.[2] In this patient, the inferior displacement of the orbital roof and orbital floor, without concomitant globe injury, was addressed with open reduction of the large orbital roof segment and alloplastic reconstruction of the orbital floor segment.

ACKNOWLEDGMENT

This work was conducted in accordance with ICMJE guidelines for authorship.