orbital fractures brig amer yaqub fcps, frcsed anatomy of orbit
TRANSCRIPT
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) ZygomaticAnterior half of the globe is vulnerable to
lateral trauma since it protrudes beyond the lateral orbital margin
FLOOR OF THE ORBITFloor is formed by three bones 1) Zygomatic 2) Maxillary 3) PalatineThe posteromedial portion of the Maxillary bone
is relatively weakMay be involved in a blowout fracture
MEDIAL WALL OF THE ORBITIt is formed by four bones 1) Maxillary 3) Ethmoid 2) Lacrimal 4) Sphenoid
Orbital cellulitis is therefore frequently secondary to Ethmoidal sinusitis
OPTIC CANALOptic canal lies in the lesser wing of
sphenoidIt is situated close to the apex of the
orbitIt connects the middle cranial fossa with
the orbital cavityIt is 4-10 mm longIt transmits, 1) Optic nerve 2) Ophthalmic artery
SUPERIOR ORBITAL FISSUREIt is a slit between the greater and lesser wing of
sphenoid boneStructures which passes through are, Superior portion contains1.Lacrimal nerve2.Frontal nerve 3.Trochlear nerve4.Superior ophthalmic vein
Inferior portion contains1.Superior & Inferior division of Oculomotor nerve2.Abducent nerve3.Nasociliary nerve4.Sympathetic fibers
INFERIOR ORBITAL FISSUREThe lateral wall and the floor of the orbit are
separated posteriorly with the inferior orbital fissure.
Which transmites.1.Maxillary nerve & its Zygomatic branch2.Ascending branches from the Sphenopalatine
ganglion3.Inferior ophthalmic vein
ORBITAL FRACTURES
BLOW-OUT ORBITAL FLOOR FRACTUREA '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 signsEcchymosis Oedema Subcutaneous emphysema.Infraorbital nerve anaesthesia Involving the lower lidCheekSide of noseUpper lipUpper teeth and gums
Diplopia
EnophthalmosManifest after a few
days, as the initial oedema resolves
Ocular damage
HyphaemaAngle recession Retinal dialysis
CT ScanExtent of the
fractureProlapsed
orbital fatExtraocular
musclesHaematoma
Hess test Useful in assessing and monitoring the
progression of diplopia
INITIAL TREATMENTAntibiotics SteroidsNo nose blowing
SURGICAL TREATMENTSurgery recommended for symptomatic
fractures DiplopiaMuscle entrapmentEnophthalmosExtensive fracture (>50% of floor)
Ideally surgery should be done within two weeks
GOALS OF SURGERYRestore normal extraocular
muscle movementsReplace orbital contents into the
orbitRestore normal orbit volume
TECHNIQUE OF SURGICAL REPAIRA 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 HemorrhageEyelid malpositionSurgical trauma to
OrbitNerveLacrimal apparatus
Blow-out medial wall fractureMost medial wall orbital fractures are
associated with floor fractures.
SIGNSPeriorbital haematoma
Defective ocular motility involving abduction and adduction.
CT will show the extent of damage
TREATMENTInvolves release of the entrapped tissueRepair of the bone defect
ROOF FRACTURECaused by trauma such as
Falling on a sharp objectBlow to the brow or foreheadMost common in young children
Complicated fractures caused by major trauma commonly affect adults
PresentationHaematoma of the
upper eyelid
Periocular ecchymosis
SIGNSInferior 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.
TREATMENTSmall 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 FRACTURERareBecause the lateral wall of the orbit is more
solid than the other wallsFracture is usually associated with extensive
facial damage
Sympathetic ophthalmia<0.5% of penetrating injurySevere bilateral granulomatous uveitisAnterior chamber inflammation, multiple yellow spots in peripheral fundus
Injured eye is called exciting eye
Fellow eye which also develops uveitis iscalled sympathizing eye
Predisposing factorsPenetrating 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 PictureExciting (injured) eye
Persistent low grade plastic uveitis, which include ciliary congestion, lacrimation and tenderness
Keratic precipitates (dangerous sign)
Sympathizing (sound) eyeUsually involved after 4-8 weeks of injury in the
other eyeMost of the cases occur within the first yearAlmost always, manifests as acute iridocyclitisRarely it may manifest as neuroretinitis or
choroiditis
Complications
Cataract Glaucoma Optic atrophy Exudative detachments Subretinal fibrosis
TreatmentProphylaxis
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
CorticosteroidsMostly good prognosis >6/18However, 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: 0.015-1.9% (lowest after planned surgery)
Treatment: immunosuppressive therapy