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