Ocular Trauma Flashcards
Causes of Blunt Ocular Trauma
Sports injury, Motor vehicle accident, Fight, Domestic accident
Pathogenesis of Blow-out Orbital Floor Fracture
Sudden increase in the orbital pressure by a striking object greater than 5cm in diameter
Blow-out Orbital Floor Fracture Signs
- Periocular: Ecchymoses, oedema, subcutaneous emphysema
- Infraorbital nerve anaesthesia
- Diplopia
Blow-out Orbital Floor Fracture Management
Refer to oculoplastic surgeon for computed tomography scan and repair of orbital floor
Blow-out Medial Wall Fracture Signs
- Periorbital haematoma and frequently subcutaneous emphysema
- Defective abduction, if medial rectus is caught in the fracture
Blow-out Medial Wall Fracture Management
Refer for further examination, treatment involves release of entrapped tissue and repair of bone defect
Blunt Trauma Cornea signs
Corneal abrasion, acute corneal oedema, tears in descemet membrane
Blunt Trauma Anterior Chamber signs
Hyphema
Blunt Trauma Anterior Uvea Signs
Pupil: Vossius Ring, Mydriasys, radial pupillary tears
Iridodialysis: D-shaped pupil and dark bi-convex area near limbus
Ciliary body: Temporary cessation of aqueous secretion
Blunt Trauma Lens signs
Cataract: rosette, Subluxation, Dislocation
Blunt Trauma Globe signs
Globe rupture
Blunt Trauma Retina and choroid signs
Commotio retinae, choroidal rupture, Retinal breaks and retinal detachment
Blunt Trauma Optic nerve signs
Optic neuropathy, optic nerve avulsion
Shaken baby syndrome presentation, systemic and ocular features
Physical abuse in children under 2 years of age, Irritability, lethargy, vomitting.
Systemic features: subdural haematoma and impact injuries to the head
Ocular features: Periorbital bruising, subconjunctival haemorrhages, poor visual response, afferent pupillary defect
Definition of penetration
Single full-thickness wound, usually caused by a sharp object, without an exit wound
Causes of penetrating trauma
assault, domestic accidents and sport
Removal of superficial foreign bodies in tarsal conjunctival
Lid is everted and FB can be removed
Removal of superficial foreign bodies in cornea
Removal with hypodermic needle after topical anaesthesia. Rust ring on bed of abrasion caused by ferrous foreign bodies must also be removed
Mechanical effects of intraocular foreign bodies
cataract, vitreous liquefication, retinal haemorrhages and tears
• Iron undergoes siderosis that results in toxic effect and cell death
• High copper content can result in endophthalmitis, low copper content less toxic
Sympathetic ophthalmitis pathogenesis
Sympathetic ophthalmitis is a bilateral granulomatous panuveitis occurring after penetrating trauma, often associated with uveal prolapse or intraocular surgery
Sympathetic ophthalmitis signs
- Exciting eye: evidence of inital trauma and is red & irritable
- Sympathising: photophobic and irritable
- Both eyes: granulomatous anterior uveitis
- Multifocal mid-peripheral choroidal infiltrates
Which chemical burns are more common and penetrate deeper
Alkali
Chemical injury pathophysiology
- Necrosis of conjunctival and corneal epithelium
- Loss of limbal stem cell
- Deeper penetration cause stromal corneal opacification
- Anterior chamber penetration results in iris and lens damage
- Ciliary epithelium damages impair secretion of ascorbates which is required to corneal repair
- Hypotony and phthisis bulbi
Emergency treatments
Without taking history
Copious irrigation, double-evesion of eyelids, debridement of necrotic epithelium
