Approach to the Red eye

Question 1

Discuss the use of pinhole testing in the assessment of eye complaints in the ED

Answer 1

Allows decreased acuity due to refractory errors to be differentiated from those that a non refractory such as retinal odema or aqueous hemorrhage

Question 2

Discuss symptomology of the red eye and what it is suggestive of

Answer 2

Two historical factors are of particular importance– rapidity of onset and sensation of foreign body

A foreign body sensation particularly when it can be localized is a strong indicator of corneal origin to the pain (foreign body, corneal abrasion, ulcer or viral or ultraviolet keratitis)

Need to characteristic the pain: itching, burning, dull, sharp diffuse or localized

Itching tends to be more often due to irritation by blepharitis, conjunctivitis or dry eye syndrome

Burning is associated with the above and often superficial complaints such as irritation from a pterygium or pinguecula, episclertitis, or limbic keratoconjuctivitis

Sharp pain generally resutls from abnormalities of the anterior eye such as corneal orrigin pain and uveitis

Dull pain which may be severe and described as a headache is oftern generalised and is typically a manifestation of icnreased IOP (acute angle closure glaucoma), vitresou infection (endopthalmitis) or referred from extra orbital pathology (sinusitis, migraine headache, temporal arteritis)

Acute orbital comprtament syndrome caused by retro-orbital haematoma presents with intense pain and progressive visual loss

Redness without pain or foreign body sensation is usually sponjt subconjunctival haemorrage and is benign

Question 3

Discuss a complete eye exam

Answer 3

VVEEPP

Visual acuity (best possible correction) 
Visual fields 
External exmaintoin
-- globe position in orbit 
--conjugate gaze
--periorbital soft tissues bones and sensation 
Extraocular muscle movement 
pupils 
pressure 
Slit lamp exmaintoin
-- including anterior chamber 
opthalmoscopy

Question 4

Discuss the external examination of the eye

Answer 4

Gross abnormalities

Globe position- subtle exopthalmos and enopthalmos are rare and best detected looking inferiorly tangentially across the forehead. Can be traumatic or non traumatic but is due to increased IOP. Medical causes include cellulitis or intraorbital or lacrimal tumors. Hyperthyroidism may cause enlargement of EOM
The most important cause of exopthamos in the ED is orbital compartment syndrome stretching the optic nerve and retinal artery. Will have raised IOP, reduced EOM and a relative afferent pupilary defect

Insepction also involves examination of the upper and lower palpebral sulci for foreign bodies or other abnormalities

Anterior chamber should be viewed without magnificnation to asses for hyphema or hypopyon. Blood in the anterior chamber is usually due to trauma. If penetration can be exlcuded the hyphema should be graded and IOP determined

Question 5

Discuss ancillary testing in the eye exam

Answer 5

Swinging flashlight test – used to determine whether a RAPD exists

IOP determiantion- causes include glucoma, suprachordial haemorrhage and space-occupying retrobulbar pathology. Major pathology not to miss is acute angle closure glaucoma. Presents with pain, onset of which is sudden in low light conditions causing pupillary dilatation. The iris is imobile and can be irregular, pupils are fixed and dilated to 5-6mm . Due to inability to contract photophobia is present

Question 6

Discuss features of slit-lamp examination

Answer 6

1) lids and lashes – inspecting for blepharitis, lid abcess, and dacryocystitis
2) conjunctiva and scleara
3) cornea
4) anterior chamber evaluated for the presence of cells and flare representing depp inflammation. Hyphema from surgery or trauma, hypopyon or foreign bodies may also be noted
5) Iris
6) Lens

Question 7

Discuss causes of inability to visualise a red reflex

Answer 7

1) Opacification of the cornea, most commonly by oedema secondary to infection or injury
2) hyphema or hypopyon within the anterior chamber
3) extremely miotic pupil
4) catarct of the lesn
5) blood in the vitreous or posterior eye wall
6) retinal detachment

Question 8

Discuss critical diagnosis in patient with a red eye

Answer 8

Caustic injury to the eye requires emergent treatment as it can lead to rapidly progressive destructive keratoconjunctivitis. Alkaline substances cause liquefactive necrosis and will progress deeply into the eye surface – acids will cause coagulative necorsis and penetrate less deeply. Ph first then morgans lens. If ph normal and nil abnormalities post irrigation nil need for ophthalmology review.

Orbtial compartment syndrome is a sight threatening illness. Occurs whenever optic pressure is high enough to cause dysfunction of the optic nerve. Retrobulbar haemtoma is usually a result of trauma but can occur spontaneously in patients with coagulopathy. Retrobulbar abcess or emphysema can also occur. These condition necessitate decompression by performing a lateral canthotmoy