Natural history
Many roof fractures do not need repair, and good outcomes are achieved with conservative management alone.
Early surgical intervention has been advocated to prevent meningitis and brain abscess formation (Jamieson, J Neurosurg. 1973).
- However, other studies indicate that medical management or delayed surgical repair does not increase morbidity (Fulcher, Ophthal Plast Reconstr Surg. 2003).
- The decision of whether and when to proceed with surgical repair should be made in conjunction with neurosurgery, as many roof fractures involve herniated brain tissue and CSF leak.
Table 1 summarizes the indications for urgent and delayed repair.
CSF fistulas occur in 0.5%–3% of craniocerebral trauma (Markovic, J Craniofac Surg 2006).
- Large dural defects need repair, usually with synthetic dural grafts, pericranium, and/or fascia lata (Pease, J Neurol Surg Rep. 2013).
- For minor CSF leaks where the dural edges are apposed or where sinus mucosa bridges the dural defect, conservative management with bed rest is curative in 85%–95% of cases (Salame, Neurosurg Focus 2000).
Traumatic optic neuropathy occurs in up to 10% of patients with craniofacial fractures (Yu-Wai-Man, Coch Collab 2009).
- Results from direct injury, ischemia, or blunt trauma.
- Treatments such as optic canal decompression and high- dose corticosteroids are controversial, with no proven benefit in randomized trials (Levin, Ophthalmology. 1999).
- Final visual potential cannot be adequately predicted.
Medical therapy
- IV antibiotics if signs of sinus disease or dural laceration/CSF leak
- High-dose corticosteroids to treat traumatic optic neuropathy are controversial.
- Consider if vision compromised on presentation.
- Methylprednisolone 250 mg IV every 6 hours for 24–48 hours (Warner, Ophthalmology. 2010)
Surgery
Surgical intervention is undertaken urgently or in a delayed fashion depending on the above criteria.
- Radiologic anatomy of the paranasal sinuses, orbital apex, and optic canal should be studied carefully in each patient to assess for anomalies or traumatic abnormalities of the anatomy.
Surgical procedures include reduction of the fracture with placement of an implant, repair of dural tear if present, obliteration or cranialization of frontal sinus (if indicated), and optic canal decompression (if indicated).
Approaches include extracranial, intracranial, and endonasal endoscopic; the approach used is determined by the surgical needs of the patient.
Extracranial approach
- Incisions include upper lid crease, brow, Lynch, bicoronal, or through an existing laceration.
- The fracture can then be approached superiorly through a supraorbital frontal craniotomy.
- Alternatively, the fracture can be approached inferiorly from the roof of the orbit in the subperiosteal plane.
- Good visualization of the anatomy; useful approach to address frontal sinus at the same time
Intracranial
- Extradural approach through a craniotomy
- Should be done in conjunction with neurosurgery
- This is the approach of choice for cases
- With large dural defects that need concomitant repair
- In which the anterior clinoid is fractured
- In which the lateral optic canal wall must be exposed
- When unroofing the plane of the sphenoid and its associated falciform dural fold is needed (Goldberg, Ophthal Plast Reconstr Surg. 1996)
Endonasal endoscopic
(Kuppersmith, Laryngoscope. 1997)
- Can be used alone or with a transconjunctival approach for optic canal decompression
- Not useful for fracture reduction
Other management considerations
Optic canal decompression can be performed through an external approach, intracranial approach, or endonasal endoscopic approach.
- From an orbital approach, the medial roof of the canal can be removed.
- The carotid artery lies inferior to the nerve, and the ophthalmic artery joins the optic nerve near the intracranial optic canal and courses inferior and lateral to the nerve (Goldberg, Ophthal Plast Reconstr Surg. 1996).
- Adequate decompression of the canal is achieved when 50% of the circumference of the canal is removed, bone along the entire length of the canal is removed, and total longitudinal incision of the dural sheath, including the annulus of Zinn, is completed (Sofferman, J Microsurg. 1979).
- Complications include injury to the internal carotid artery, thermal injury to the optic nerve from drilling, and enophthalmos.
If there is compromise of the nasofrontal duct in a frontal sinus fracture, the sinus should be obliterated. If the posterior table of the frontal sinus is fractured and the anterior table intact, the frontal sinus can be cranialized.
For small, minimally displaced roof fractures with entrapment of the superior rectus or oblique muscle, repositioning of the intraocular contents without placement of a graft is often all that is necessary.
With larger defects, the surgeon has several options for reduction. The ideal implant should mold to the contour of the defect, be stable over time, inert, and radiopaque.
- Bone grafts
- Calvarium, rib, or ilium are most common harvest sites.
- Advantages include biocompatible, radiopaque, no additional cost.
- Disadvantages include longer operative time, donor site morbidity, can be difficult to contour, and risk of resorption (Kim, Arch Plast Surg. 2012 and Manolidis, J Craniofac Surg 2002).
- Titanium mesh (Kim, Arch Plast Surg. 2012 and Mokal Craniomaxillofac Trauma Reconstr. 2012)
- Advantages include ease of contouring, radio-opacity, low risk of infection, stability, and no donor site morbidity.
- Disadvantages include high cost and sharp edges if not trimmed properly (Lazaridis, Aust Dent J 1998).
- Porous polyethylene
- Advantages include stability and biocompatible.
- Disadvantages include radiolucent and high cost (Rubin, Ophthalmology 1994).
- Composite materials (porous polyethylene imbedded with titanium)
- Advantages include radio-opaque, ease of contouring, more rigid than porous polyethylene alone, better tissue incorporation than titanium alone (Mokal, Craniomaxillofac Trauma Reconstr. 2012).
- Disadvantages include cost and small risk of infection.
- Nylon foil (Supramid)
- Advantages include cost and stability.
- Disadvantages include radiolucent, risk of capsule formation, and inability to mold the implant (Custer, Ophthal Plast Reconstr Surg 2003).
Young patients with associated blepharoptosis and strabismus should be followed closely to monitor for amblyopia.
Common treatment responses, follow-up strategies
Many patients regain full visual potential and motility.
Patients with traumatic optic neuropathy should be counseled that their final visual potential is unknown.
Patients with residual strabismus and ptosis not secondary to bony impingement might benefit from repair. These should be observed for at least 6 months after the injury, as many will resolve with time.