Paediatric Ophthalmology

Question 1

Peri-orbital cellulitis (pre-septal cellulitis) - state the following:
- Pathophysiology
- Most common age
- Presentation (including any red flags)
- Investigations
- Management

Answer 1

Pathophysiology:
- Inflammation and infection of the peri-orbital soft tissue (pre-septal infection) separate from orbital cellulitis (post-septal)
- Bi-modal seasonal variation, late winter and early spring
- Generally contiguous spread from surrounding superficial or peri-orbital structures e.g. paranasal sinuses (common in patients with sinusitis)
- Concerning as may rapidly progress to orbital cellulitis in children

Most common age:
- Primarily of children and adolescents (0-15 years)
- Peak incidence under 10 years
- M:F ratio 2:1 (twice as many males affected)

Presentation:
- Eyelid oedema and erythema
- NO orbital signs (normal vision, no proptosis and full movements of eye without pain)
RED FLAGS
- Pain on movements
- Decreased visual acuity / loss of red colour vision
- Proptosis / exophthalmos
- Irritation / swelling conjunctiva (chemosis)
- Painful diplopia

Investigations:
- Comprehensive ophthalmic examination / anterior rhinoscopy
- Culture of discharge from nasal passages (if purulent)
- CT scan
- Consider bloods (raised CRP, WCC - doesn’t differential type)

Management - strictly mild peri-orbital cellulitis:
- Broad spectrum oral antibiotics
- If suspect orbital cellulitis = hospital admission and IV antibiotics

Question 2

Orbital cellulitis (post-septal cellulitis) - state the following:
- Pathophysiology
- Most common age
- Presentation (including any red flags)
- Investigations
- Management

Answer 2

Pathophysiology:
- Inflammation and infection of the orbital soft tissue (post-septal infection) with associated ocular dysfunction
- Generally contiguous spread from bacterial sinus infection
Warrants hospital admission!!

Most common age:
- Peak incidence under 10 years
- M:F ratio 2:1 (twice as many males affected)

Presentation:
- Eyelid oedema and erythema
Orbital signs
- Pain on movements
- Decreased visual acuity / loss of red colour vision
- Proptosis / exophthalmos
- Irritation / swelling conjunctiva (chemosis)
- Painful diplopia

Investigations:
- Immediate referral for hospital admission
- Ophthalmic examination
- CT scan with contrast
- Consider bloods (raised CRP, WCC - doesn’t differential type)

Management - strictly mild peri-orbital cellulitis:
- Urgent hospital admission
- IV antibiotics
- If abscess present: incision, drainage, and culture

Question 3

State organisms most commonly causing peri-orbital cellulitis

Answer 3

• Staphylococcus aureus (most common)
• Streptococcus pneumoniae
• Haemophilus influenzae
• Moraxella catarrhalis
• Group A streptococcus

(generally responsible for acute rhinosinusitis)

Question 4

State some differentials for peri-orbital cellulitis

Answer 4

• Orbital cellulitis
• Vesicles of herpes zoster ophthalmicus
• Contact dermatitis of eye
• Atopic dermatitis
• Stye
• Meibomian cyst
• Inflammation of the lacrimal sac (dacryocystitis)
• Blepharitits

Question 5

State some complications of untreated peri-orbital cellulitis

Answer 5

Visual-related complications:
- Papilloedema or neuritis, leading to loss of vision

Life-threatening intracranial complications:
- Encephalomeningitis
- Cavernous sinus thrombosis
- Sepsis
- Intracranial abscess