Orbital fractures: Timing of surgical repair

Abstract

Orbital fractures are common in the setting of facial trauma. Trauma can result in the fracture of one or more walls of the orbit, with orbital floor and medial wall being commonly involved. Orbital floor blow-out fractures initially were attributed due to the compression of the globe and resultant hydraulic pressure on the orbital floor (Smith and Regan, 1957). However later it was felt that perhaps the forces applied to the inferior orbital rim were transmitted posteriorly to the thin orbital floor resulting in buckling and producing an indirect orbital floor fracture. More recent theories suggest that perhaps combination of the hydraulic theory and indirectly transmitted force may result in the orbital floor fracture. Lateral orbital wall fractures are commonly seen with zygomatic malar complex (ZMC) fractures and most frequently occur as a result of road traffic accidents, assault, work-related and sport-related accidents. These fractures are more frequent in young males and uncommon in children. Pediatric orbital floor fractures may behave differently than fractures in adults. Children may present with minimal ecchymosis or erythema, profound vertical motility restriction and minimal radiological findings as compared to adults. Floor fracture in these patients may present as trap-door that may entrap the inferior rectus muscle or its peri-muscular soft tissues resulting in nausea/vomiting and motility restriction. Blindness may accompany orbital fracture that may occur due to globe injury or injury to the optic nerve. Injury to the globe has been reported in up to 30% of orbital fractures. Indirect injury to the intra-canalicular portion of the optic nerve is most common mechanism of optic nerve related visual loss. Some of the other mechanisms of visual loss may include retrobullbar hemorrhage, penetrating foreign body and bony fragment impinging on the optic nerve. In addition to the clinical assessment, imaging studies play an important role in diagnosing and determining the extent of the orbital wall fractures. Management of orbital wall fractures is directed toward early detection and emergent treatment of associated intracranial and eye injuries (Burnstine, 2003). Although, Putterman et al. (1974) advocated observation in cases of patients presenting with primary gaze diplopia and limited vertical ductions as nearly all cases of diplopia in their series had resolution. Hawes and Dortzback (1983) on the other hand noted that post-operative enophthalmos was minimized if floor defects measuring >50% were repaired within two week of trauma. More recently, Dal Canto and Linberg (2008) found that patients faired equally weather their orbital floor fractures were repaired within 14 days or within 29 days after trauma. In their study, the end results showed no statistical difference in post-operative binocular diplopia when comparison of early versus late fracture repair was made. There was no difference in the need for post-operative strabismus surgery or need for prisms when comparing early versus delayed repair. One need to be aware, however that delayed repair may be technically more challenging. Obviously results of Dal Canto and Linberg, do not apply to “white-eyed blowout fractures,” and to those with a non-resolving oculocardiac reflex. Similar recommendations had been made by Simon et al. (2008), who reported that post-operative outcomes were similar between those patients with orbital floor fractures who had early repair when compared to those with late repair. Simon et al, have provided additional insight into the clinical course of subset of orbital floor fractures (Simon et al., 2008). For example, in young adults, limitations may not be caused by obvious muscle entrapment but rather injury to the muscle or soft tissue that may resolve over 6–9 months without a surgical repair. Surgical complications can include but are not limited to optic nerve injury, blindness, vision loss, infection or migration of implanted material, pyogenic granuloma formation, post-operative mydriasis, epiphora, worsening diplopia, and lid malpositioning (Burnstine, 2003; Putterman et al., 1974; Hawes and Dortzback, 1983; Dal Canto and Linberg, 2008; Simon et al., 2008). Depending on timing of the fracture repair, significant percentage of patients with orbital fracture may continue to have persistent post-operative diplopia. Various kind of implant materials have been used to repair orbital fractures over the years. Titanium implants have been found to be very desirable due to their ability to integrate into native tissue and thus avoid extrusion. However, this ability to integrate and cause fibrosis may contribute to the complications seen with titanium implants. Lee and Nunery (2009) reported cases of diplopia due to extraocular motility restriction and/or cicatricial eyelid retraction following repair of orbital fracture with titanium implants. To avoid orbital adherence syndrome, Lee and Nunery (2009) recommend the use of a nonporous, nonreactive implant for orbital fracture repair with minimal eyelid dissection and placing the plates as far as possible away from the orbit and eyelid tissue. In this issue of Saudi Journal of Ophthalmology, Alsuhaibani (2010) has reviewed significance of lateral orbital wall fractures, associated complications and difficulties in repairing such fractures. The author has very nicely detailed the causes, mechanism, relevant anatomical considerations, diagnosis, relevance of proper imaging studies and the need for repair of such fractures for normal functioning and cosmetic well being of patients after trauma. The author emphasizes on the value of 3-dimensional CT-scan that may facilitate the evaluation of patients with facial trauma by displaying the spatial orientation of the bone fragments and fracture gaps. The management of the lateral orbital wall fracture depends on the degree of displacement and comminution of the fracture, and intracranial extension of sphenoid fracture. The repair is indicated if the displaced lateral wall fracture causes visual loss, significant enophthalmos or ocular motility disturbance. Enophthalmos has been described as one of the main consequences of delayed or inadequate reduction of the ZMC fracture and is more likely in patients with multiple traumas compared with patients with localized orbital traumas. The author emphasizes that enophthalmos is easier to manage shortly after trauma as with time, scaring, bone resorption and malunion of the fracture makes the management more complicated. The author recommends management of intracranial or eye injuries on emergent basis. After which significantly displaced lateral wall fractures need to be repaired on timely basis. Proper realignment of the plane of the lateral orbital wall at the sphenozygomatic suture along with the other complex articulations of the zygomatic bone is paramount for proper functional and aesthetic outcome.