Orbital cellulitis

Question 1

What is orbital cellulitis?

Answer 1

infection affecting the fat and muscles posterior to the orbital septum and within the orbit

DOES NOT involve the globe.

Question 2

What usually causes orbital cellulitis?

Answer 2

spreading upper respiratory tract infection from the sinuses

Question 3

Describe the difference between Orbital and Periorbital cellulitis

Answer 3

Periorbital = less serious superficial infection anterior to the orbital septum

Orbital= posterior to orbital septum

Question 4

What causes periorbital cellulitis?

Answer 4

superficial tissue injury (chalazion, insect bite etc…)

Question 5

Periorbital cellulitis can progress to orbital cellulitis. TRUE/FALSE?

Answer 5

TRUE

Question 6

Risk factors for orbital cellulitis

Answer 6

• Childhood
• Previous sinus infection
• No HiB vaccination
• Recent eyelid infection/ insect bite on eyelid

Question 7

Clinical features of orbital cellulitis

Answer 7

Red/swollen eye
Pain
Visual disturbance
Proptosis
Pain with eye movements
Eyelid oedema and ptosis

Question 8

What signs are present in orbital cellulitis but NOT in periorbital cellulitis

Answer 8

reduced visual acuity
proptosis
ophthalmoplegia/pain with eye movements

Question 9

What investigations may be relevant in orbital cellulitis?

Answer 9

Full blood count
- WBC elevated
- raised inflammatory markers

CT with contrast
- Inflammation of the orbital tissues deep to the septum

• Blood culture
• swab

Question 10

Most common bacterial causes of orbital cellulitis

Answer 10

Streptococcus
Staphylococcus aureus
Haemophilus influenzae B.

Question 11

Management of orbital cellulitis

Answer 11

Admission to hospital
IV antibiotics