14.01.22 Ophthalmology

Herpes

• • Dendritic pattern

  • DON'T give steroids

Cellulitis

• • Pre-septal

    • Anterior to orbital septum

    • Oral Abx

  • Orbital

    • Posterior to orbital septum

    • Often from sinusitis

    • Clinical signs: Reduced mobility, Proptosis, Reduced vision (colour lost first), RAPD, Optic disc oedema, Painful movements

    • => Optic nerve damage, Meningitis

    • Orbital CT, IV Abx, Cultures

CRAO

• • Pale macula

  • Cherry-red spot at fovea - Blood supply from posterior ciliary arteries

Corneal abrasion

• • Pain, tears, photophobia

  • Oxybuprocaine + fluorescein

  • Try (once) to remove with cotton bud

  • 5/7 topical chloramphenicol

  • Safety net

  • Any metal - refer to ophthalmology

Subconjunctival haemorrhage

• • WHY DID IT HAPPEN??

    • Warfarin, Head injury, NAI

  • Exclude hyphaema (no blood in anterior chamber)

Burns

• • Acid => Coagulative necrosis

  • Alkali => Liquefactive necrosis

    • Much worse

    • Keeps going deeper

  • Irrigate until pH is normal (7.0 - 7.3)

  • Then refer to ophthalmology

Ruptured globe

• • Tear-drop pupil - Points to injury

  • STOP EXAMINING

  • Cover with cup + refer to ophthalmology

Orbital blowout fracture

• • Will happen before the globe ruptures

  • Check for muscle/nerve entrapment - esp. inferior rectus

    • => Can't look up

  • This is an open fracture (maxillary sinus) => Abx

Retrobulbar haematoma

• • Compartment syndrome of the eye

  • => Optic nerve pressure / Ischaemia

  • Can do lateral canthotomy

Random notes

• • Contrindications to dilation

    • Head trauma, ?Ruptured globe, Glaucoma

  • Schaffer's sign

    • Clumping of pigmented cells in anterior chamber and on corneal endothelium. Also known as "tobacco dust".

  • Upper zone fibrosis

    • B - Beryllium

    • R - Radiation

    • E - Extrinsic allergic alveolitis

    • A - Ankylosing spondylitis / Aspergillus

    • S - Silicosis

    • T - TB

    • S - Sarcoidosis

  • C - Coal Workers pneumoconiosis

  • L - Langahans Cell histiocytosis

  • A - Ankylosing Spondylitis

  • P - Psoriasis

  • Lower zone

    • D - Drugs (AMEN: Amiodarone, Methotrexate, Ergot-derivatives, Nitrofurantoin)

    • R - Rheumatoid arthritis

    • C - Connective tissue disease

    • I - Idiopathic Pulmonary Fibrosis

    • A - Asbestosis

  • S - Systemic sclerosis