ORBITAL FRACTURES Brig Amer Yaqub FCPS, FRCSEd

ANATOMY OF ORBIT

ROOF OF THE ORBIT Roof is formed by two bones 1) Lesser wing of Sphenoid 2) Orbital plate of the Frontal It is located subjacent to the anterior cranial fossa and frontal sinus A defect in orbital roof may cause pulsatile proptosis

LATERAL WALL OF THE ORBIT Lateral wall is formed by two bones 1) Greater wing of Sphenoid 2) Zygomatic Anterior half of the globe is vulnerable to lateral trauma since it protrudes beyond the lateral orbital margin

FLOOR OF THE ORBIT Floor is formed by three bones 1) Zygomatic 2) Maxillary 3) Palatine The posteromedial portion of the Maxillary bone is relatively weak May be involved in a blowout fracture

MEDIAL WALL OF THE ORBIT It is formed by four bones 1) Maxillary 3) Ethmoid 2) Lacrimal 4) Sphenoid Orbital cellulitis is therefore frequently secondary to Ethmoidal sinusitis

OPTIC CANAL Optic canal lies in the lesser wing of sphenoid It is situated close to the apex of the orbit It connects the middle cranial fossa with the orbital cavity It is 4-10 mm long It transmits, 1) Optic nerve 2) Ophthalmic artery

SUPERIOR ORBITAL FISSURE It is a slit between the greater and lesser wing of sphenoid bone Structures which passes through are, Superior portion contains 1. Lacrimal nerve 2. Frontal nerve 3. Trochlear nerve 4. Superior ophthalmic vein Inferior portion contains 1. Superior & Inferior division of Oculomotor nerve 2. Abducent nerve 3. Nasociliary nerve 4. Sympathetic fibers

INFERIOR ORBITAL FISSURE The lateral wall and the floor of the orbit are separated posteriorly with the inferior orbital fissure. Which transmites. 1. Maxillary nerve & its Zygomatic branch 2. Ascending branches from the Sphenopalatine ganglion 3. Inferior ophthalmic vein

ORBITAL FRACTURES

BLOW-OUT ORBITAL FLOOR FRACTURE A 'pure' blow-out fracture of the orbit does not involve the orbital rim Whereas an 'impure' fracture involves the orbital rim and adjacent facial bones It is caused by a sudden increase in the orbital pressure by a striking object which is greater than 5 cm in diameter Fracture most frequently involves the floor of the orbit Occasionally, the medial orbital wall may also be fractured.

Periocular signs Ecchymosis Oedema Subcutaneous emphysema. Infraorbital nerve anaesthesia Involving the lower lid Cheek Side of nose Upper lip Upper teeth and gums

Diplopia Enophthalmos Manifest after a few days, as the initial oedema resolves Ocular damage Hyphaema Angle recession Retinal dialysis

CT Scan Extent of the fracture Prolapsed orbital fat Extraocular muscles Haematoma

Hess test Useful in assessing and monitoring the progression of diplopia

INITIAL TREATMENT Antibiotics Steroids No nose blowing

SURGICAL TREATMENT Surgery recommended for symptomatic fractures Diplopia Muscle entrapment Enophthalmos Extensive fracture (>50% of floor) Ideally surgery should be done within two weeks

GOALS OF SURGERY Restore normal extraocular muscle movements Replace orbital contents into the orbit Restore normal orbit volume

TECHNIQUE OF SURGICAL REPAIR A transconjunctival or subciliary incision The periosteum is elevated from the floor of the orbit and orbital contents are removed from the antrum The defect in the floor is repaired using synthetic material such as Supramid, silicone or Teflon The periosteum is sutured

COMPLICATIONS Diplopia (up to 75%) Exophthalmos Hemorrhage Eyelid malposition Surgical trauma to Orbit Nerve Lacrimal apparatus

Blow-out medial wall fracture Most medial wall orbital fractures are associated with floor fractures.

SIGNS Periorbital haematoma

Defective ocular motility involving abduction and adduction.

CT will show the extent of damage

TREATMENT Involves release of the entrapped tissue Repair of the bone defect

ROOF FRACTURE Caused by trauma such as Falling on a sharp object Blow to the brow or forehead Most common in young children Complicated fractures caused by major trauma commonly affect adults

Presentation Haematoma of the upper eyelid Periocular ecchymosis

SIGNS Inferior or axial displacement of the globe. Large fractures may be associated with pulsation of the globe unassociated with a bruit Best detected on applanation tonometry.

TREATMENT Small fractures may not require treatment Observe the patient for the possibility of a CSF leak which may lead to meningitis Sizeable bony defects with downwardly displaced fragments usually require reconstructive surgery

LATERAL WALL FRACTURE Rare Because the lateral wall of the orbit is more solid than the other walls Fracture is usually associated with extensive facial damage

Sympathetic ophthalmia <0.5% of penetrating injury Severe bilateral granulomatous uveitis Anterior chamber inflammation, multiple yellow spots in peripheral fundus Injured eye is called exciting eye Fellow eye which also develops uveitis is called sympathizing eye

Predisposing factors Penetrating wound ( less commonly intraocular surgery) Wounds in the ciliary region Wounds with incarceration of the iris, ciliary body or lens capsule More common in children than in adults

Clinical Picture Exciting (injured) eye Persistent low grade plastic uveitis, which include ciliary congestion, lacrimation and tenderness Keratic precipitates (dangerous sign) Sympathizing (sound) eye Usually involved after 4-8 weeks of injury in the other eye Most of the cases occur within the first year Almost always, manifests as acute iridocyclitis Rarely it may manifest as neuroretinitis or choroiditis

Complications Cataract Glaucoma Optic atrophy Exudative detachments Subretinal fibrosis

Treatment Prophylaxis Early enucleation of the injured eye (best prophylaxis when there is no chance of saving useful vision) When there is hope of saving useful vision, following steps should be taken: Meticulous repair of the wound using microsurgical technique should be carried out, taking great care that uveal tissue is not incarcerated in the wound Immediate treatment with topical as well as systemic steroids and antibiotics along with topical atropine should be started Late enucleation if uveitis not settled for 2 wks

Systemic immunosuppression Corticosteroids Mostly good prognosis >6/18 However, enucleate only if no visual potential

SYMPATHETIC OPHTHALMIA (BILATERAL granulomatous panuveitis after trauma)  Onset: 5 days to 66 years after penetrating trauma  Onset: 33% at 3 mo., <50% after 1 year  Removal of injured eye after onset does not help  Cause: antigen-antibody interaction  Risk: % (lowest after planned surgery)  Treatment: immunosuppressive therapy