CGI & Chemical injuries OF THE EYE Ayesha S Abdullah 18.03.2016

Learning outcomes By the end of this lecture the students would be able to Differentiate between OGI and CGI Diagnose CGI of the eye, identify its complications and outline the principles of management of these injuires specially in case of hypahema Describe the epidemiology of chemical ocular injuries, correlate the pathophysiology of chemical injury with acids and alkali to the clinical presentation & complications , Explain the first aid measure and later management of a case with chemical injury. Identify the complications of chemical injury and correlate it with the underlying pathology, suggest ways for the primary, secondary and tertiary prevention of such injuries

Close globe injury (CGI) Definition Mechanism AP compression Expansion in the equatorial plan Transient & excessive increase in IOP Impact is primarily absorbed by ?? Lens –Iris diaphragm & vitreous The damage can happen to any tissue of the eye Commonly has long-term effects/ sequelae

Close Globe Injuries Choroidal tear Commotio retinae Subconjunctival Haemorrhage Corneal abrasion Acute corneal oedema Traumatic iritis Traumatic Mydriasis / Miosis Hyphaema Iridodialysis Cyclodialysis / Angle recession Ciliary shock Choroidal tear Commotio retinae Posterior Vitreous Detachment Vitreous haemorrhage Retinal tears Retinal Detachment Optic Nerve Evulsion

Close Globe Injuries 5-6-6 Conjunctiva, Cornea & Lens Subconjunctival Haemorrhage Corneal abrasion Acute corneal oedema Subluxation and dislocation of lens Cataract Iris & IRCA Traumatic iritis Traumatic Mydriasis / Miosis Hyphaema Iridodialysis Cyclodialysis / Angle recession Ciliary shock Posterior Segment Choroidal tear Commotio retinae Posterior Vitreous Detachment Vitreous haemorrhage Retinal Breaks & Retinal Detachment Optic Nerve Evulsion 5-6-6

Hyphaema Source of bleeding? Iris /ciliary body / both Immediate threat – Secondary haemorrhage Can happen up to a week, mostly first 24 hrs The haemorrahge is larger than the original bleed Most common problem is raised intraocular pressure

Hyphaema Most hyphaemas resolve without complications but complications can happen with long standing cases The most vision threatening complications are, secondary glaucoma optic nerve damage corneal staining The greater the extent of hypahema greater the chances of complications i.e blood filling more than half of the AC

Treatment of Hyphaema Small (less than 1/3rd of the AC) can be managed at home Larger hyphaema requires hospitalization for closer monitoring to avoid secondary bleed and complications For lowering the IOP; beta blockers, Alpha agonist , Carbonic Anhydrase (CA) inhibitors For associated traumatic uveitis; topical steroids Immobilization of the iris in the dilated position to avoid secondary haemorrhage; mydriatics

Hyphaema

Other injuries with blunt trauma Corneal abrasion/ ulcer

Other injuries with blunt trauma Corneal abrasion/ ulcer

Subconjunctival haemorrhage

Iridodialysis and angle recession

Traumatic mydriasis

Subluxation and dislocation of the lens

Posterior segment complications- retinal Hge, vitrous Hge, Retinal tear and RD (B scan)

Posterior segment complications Choriodal breaks and scars Commotio retinae (Berlin’s oedema ) Optic nerve evulsion

Black Eyes- Ecchymosis

Panda Eyes Fracture base of the skull

Case Gul Nawaz aged 35 years presented to emergency deparment with injury to the right eye while working in a cement factory. He had severe ocular irritation with watering, pain and photophobia. The eye was extensively washed till the normal pH was restored On examination VA OD=CF 1 m, OS=6/5 He had red eye with corneal haze There was limbal ischemia affecting less than 1/3rd of the limbus (3 clock hours) The IOP was 24 mmHg OD, 11 mmHg OS Examine the given photograph

Questions What kind of injury is this- Acid/ Alkali? Would it make any difference? Which is more common- Acid or Alkali injury? Why was the eye washed first? What is limbal ischemia and what is its significance in this patient? Why was the IOP raised? What would be the prognosis of this kind of injury? What complications immediate (primary) and late (secondary) can happen?

Some more Questions Which is the commonest alkali responsible for ocular burns? Name the alkali that causes the most serious ocular injury? Which is the commonest acid responsible for ocular burns? Name the acid that causes the most serious ocular injury? List 5 Common sources of alkali and acids.

List three factors that determine the severity of chemical burns of the eye. How does corneal healing happen in a case of chemical corneal burn? List 5 ocular examinations that you must perform to ascertain the degree of chemical injury of the eye. What are the principles of management of chemical ocular burns? What is the first aid management of chemical ocular injury?

Grade the following ocular chemical burns 1

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