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An injury resulting in an increase in intra-orbital pressure has ‘blown out’ the floor of the left orbit with the displacement of fragments into the maxillary sinus.
- The depressed fragment appears as an oblique line or ‘trapdoor‘ near the roof of the maxillary sinus.
- prolapsed soft tissue classically gives rise to the ‘teardrop‘ sign.
- Maxillary sinus opacification is seen with an air-fluid level.
- Inferior orbital rim and lateral wall of the maxillary sinus should be intact.
- Sometimes orbital emphysema is the only radiographic evidence that can be seen.
- Overlying soft tissue is a nonspecific finding.
History and examination
- mechanism of injury — typically blowout fractures result from an injury that increases the intraorbital pressure such as a blow from a fist or a small ball striking the eye/orbit at high speed.
- pain (especially on vertical movement),
- local tenderness,
- diplopia (especially on vertical gaze),
- eyelid swelling and crepitus after nose blowing
Looking Straight ahead
- enophthalmos / Proptosis
- diplopia: Eye movement, particularly upward gaze, may be restricted in orbital blow-out fractures due to trapping of the herniated inferior rectus muscle, resulting in diplopia
- infraorbital hypoesthesia: check for infraorbital nerve involvement — anesthesia of the affected cheek, and the upper teeth and gums on the affected side. this nerve passes along the floor of the orbit and is stretched or otherwise damaged.
- complete eye examination (eg Visual acuity ) looking for evidence of ocular injury, e.g. hyphema, subconjunctival hemorrhage (Subconjunctival hemorrhage with no visible posterior margin is a useful sign usually indicating orbital wall fracture), retro-orbital hemorrhage, retinal detachment, and vitreous hemorrhage.
- palpate for localized tenderness and for crepitus
- A CT scan of the orbits and brain may be required depending on the mechanism and associated injuries.
- facial radiographic views are often insufficient.
- apply an ice pack to the orbit for 1-2 days
- nasal decongestants for 1 week
- prophylactic antibiotics
- instruct the patient to avoid nose blowing and valsalva maneuvers; and to avoid driving until diplopia resolves.
- Any eye involvement (e.g. reduced visual acuity or diplopia) is an indication for urgent referral to a maxillofacial surgeon and/or an ophthalmologist.
Injuries associated with the blow out fractures
- Ruptured globe
- Retroorbital hemorrhage
- Vitreous hemorrhage
- Dislocated lens
- Secondary glaucoma
- Retinal detachment
What injuries need to be considered if the patient has a relative afferent pupillary defect in the left eye?
This suggests the presence of traumatic optic neuropathy, vitreous hemorrhage, retinal detachment or intracranial injury (e.g. asymmetric damage to the optic chiasm).
Traumatic optic neuropathy may result from:
- compressive optic neuropathy — retrobulbar hemorrhage, orbital foreign body or orbital emphysema
- optic nerve sheath hematoma
- optic nerve head avulsion
- optic nerve laceration
- Emergent ophthalmologist consultation is warranted.
Robulbar hemorrhage – Rare, rapidly progressive life-threatening emergency that results in accumulation of blood in the retrobulbar space – Increased IOP stretching of the optic nerve & blockage of ocular perfusion
Proptosis, marked subconjunctival ecchymosis & edema – Features suggesting progressive retrobulbar hemorrhage require an emergency decompression (lateral canthotomy)
What general advice should be given to patients regarding their injury
- Avoidance of nose blowing as this may produce surgical emphysema
- Not to occlude the nose when sneezing
- Application of ice packs to the area to reduce swelling
- Taking regular analgesia
- General head injury advice