Orbital Fracture

  • A wide range of ocular trauma can occur concomitant with orbital fractures. The ocular Sequelae of mid-facial fractures are usually considered to be edema and ecchymosis of {the} soft tissues, subconjunctival hemorrhage, diplopia, iritis, retinal edema, Ptosis, enophthalmos, ocular muscle paresis, mechanical restriction of ocular movement and nasolacrimal disturbances. More severe injuries such as optic nerve trauma and retinal detachments have also been reported. Made known rates of intraocular injury range from 1% to nearly 70%

  • The relationship, if any, between {the} purity of orbital fractures and their secondary ocular problems has not been elucidated to date.

  • Intraocular injuries occur in a wide pattern when orbital bones are fractured. While numerous studies have reminded {the} community of {the} importance of {the} ophthalmic examination in patients who sustain orbital fractures, to date, there have been only a handful of studies which focus on {the} incidence of intraocular injuries in patients with fracturesOcular Injury
  • Of these, there is no agreement as to {the} incidence of injury. It is likely that {the} specialty of {the} physician conducting {the} research might account for {the} inconsistencies. In contrast, since our hospital protocol requires that all orbital fractures receive an ophthalmic examination, we believe that our results are unbiased; {the} true incidence of intraocular injury is approximately 17%.


Diplopia field: limit on up or downgaze: r/o IR entrapment vs hemorrhage/edema alone: CTEvaluation - Full Ophthalmic Exam Plus

  • Hertel

  • hypo-ophthalmos (globe ptosis)

  • orbit/lid emphysema 2nd to sinus wall fracture

  • IOP straight and upgaze (might inc w/IR entrapment)

  • infraorbital anesthesia in floor fracture

  • forced generation, forced duction

  • lid measurements (PF and MRD1)

Mechanism


The rates of injury were also compared between pure orbital floor fractures (only floor) and impure (floor and rim). Of patients who sustained a pure orbital floor fracture, intraocular injuries occurred in 5.6%, compared with only 2% that sustained an impure fracture. Intraocular injuries are more common in patients who sustained PURE orbital fractures than in patients with rim involvement (IMPURE) (p=0.05). This difference suggests that {the} mechanism of injury might not be {the} same in each; it might not simply be solely direct force transmitted to {the} rim as {the} buckling theory suggests.Intraocular Injuries

  • Recall that {the} "retropulsion" theory refers to a fracture of {the} orbital floor caused by sudden increase in intraorbital pressure (BLOW-OUT) which occurs when an object with sufficient force hits {the} aperture of {the} orbit and forces {the} soft orbital contents posteriorly. Such trauma is created by objects larger than {the} horizontal diameter of {the} orbit, such as from a fist or a ball. On {the} other hand, {the} "buckling theory" proposes that {the} force transmitted through {the} rigid orbital rim directly to {the} thin floor , causes {the} floor to fracture, usually leaving {the} rim intact.

  • If we accept that impure fractures are {the} result of direct trauma to {the} orbital rim and resultant buckling of {the} floor, then we would expect similar rates of intraocular injury between pure and impure orbital fractures. This would be {the} case IF {the} buckling theory is {the} correct theory for pure fractures, since both are created by {the} same direct force to {the} rim.

  • However, we find that {the} incidence of injury is significantly higher in {the} pure fracture group suggesting that a different mechanism is at play. It is more reasonable to envision that {the} acute rise in orbital pressure would lead not only to {the} floor fracturing, but also to a greater incidence of intraocular injury as {the} globe retropulses. One could argue, however, that in {the} case of {the} impure fracture, {the} rate of injury is lower because {the} force is blunted by {the} rim. Nevertheless, we believe that these data suggest that {the} retropulsion theory might be {the} more likely explanation for orbital fractures; one theory (retropulsion) can explain variations of ocular findings in both pure and impure fractures 

 

 

Buckling:

  • It states that {the} orbital rim buckles and transmits forces to {the} orbital walls, resulting in an orbital floor fracture.

Retropulsion

 

  • The "retropulsion" theory, advanced by Smith and Regan, refers to a fracture of {the} orbital floor caused by sudden increase in intra-orbital pressure; a fracture might result from {the} hydraulic forces generated in {the} closed orbital cavity.

  • Blows from a fist, for instance, or objects larger than {the} horizontal diameter of {the} orbit, are {the} most frequent cause of this type of fracture

Globe to Wall:

 

Consequences of trauma

Double Vision

  • Results from an inability of both eyes to move equally

  • The "buckling" theory maintains that an anterior force is transmitted back into {the} orbit.

  • See pre-operative and post-operative photos below illustrating down gaze limitation of {the} right eye.

Illustrations of relevant orbital anatomy

 

 

 

 

Surgery Indications

  • residual marked diplopia w/in 30of 1o gaze 2o to restriction (of IR)

  • large (50%) floor fracture especially with large med wall fracture because likely to get enophthalmos

  • enophthalmos > 2 mm: usually there is initial proptosis 2o to orb infl/edema which resolves; if initial enophthalmos or no prop, later surgery for enophthalmos more likely

 

  • surgical repair easier within {the} originally 2 weeks

  • surgical steps: usually inferior fornix incision, raise periorbita from orb floor, free tissues from fracture, implant (silastic or miniplate depending on size) over floor defect

 

Medial Orbital Fracture

  • if indirect (blowout) extension of floor fracture, no surgery needed unless medial rectus (MR) entrapped

  • lid/orbit emphysema common

  • direct naso-orbital fracture more serious, depressed nasal bridge; compl inlc cerebral/ocular damage, ant ethmoid art. damage with severe epistaxis, CSF rhinorrhea, traumatic telecanthus, needs miniplate stabilization

Zygomatic Fracture

  • tripod fracture often has 4 zygoma breaks at lateral & inferior orb rim, zygoma arch, lateral wall of maxillary sinus

  • can involve orb floor

  • if displaced, can have cosmetic deformity, trismus (2o to impingement on coronoid process of mandible)

Orbital Apex Fracture

  • often w/traumatic optic neuropathy (needs spinal cord dose IV steroids, maybe decompression w/in 5 days, see neuro-op), other fractures

  • look for CSF rhinorrhea, cartoid-cavernous (CC) fistula

Orbital Roof Fracture

  • infrequent

  • might have intracranial lesions, CSF rhinorrhea, pneumocephalus

  • neurosurgery consult

Orbital Emphysema

  • if severe can cause CRAO, etc if loculated ball valve type wound

  • usually smaller medial wall injuries

  • air usually located in area of wound

  • if decreased Vision, high dose steroids

  • air decompression:

  • CT for localization

  • retrobulbar needle into air pocket

  • fill syringe with saline, take out plunger, watch for bubbles to appear

  • look on CT for intracranial air: needs neurosurgery consult 

Treatment

  • most fractures do not require surgery

     

early surgery for marked muscle restriction confirmed on CT, forced duction

 

should observe 1-2 weeks, oral steroids (prednisone 1 mg/kg/day with taper) to decrease swelling and fibrosis

 

antibiotics (Keflex) and nasal decongestants (Afrin), tell patient not to blow nose to decrease orbital emphysema

 



 
Procedures
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