Cellulitis, Periorbital & Orbital

Key Features

Essentials of Diagnosis

• The fascia of the eyelids joins with the fibrous orbital septum to isolate the orbit from the lids

• The orbital septum helps decrease the risk of an eyelid infection extending into the orbit

• Infections arising anterior to the orbital septum are termed preseptal

• Orbital cellulitis denotes infection posterior to the orbital septum and may cause serious complications, such as an acute ischemic optic neuropathy or cerebral abscess

General Considerations

• Preseptal (periorbital) cellulitis

  • Usually arises from a local exogenous source such as an abrasion of the eyelid, from other infections (hordeolum, dacryocystitis, or chalazion), or from infected varicella or insect bite lesions

  • Staphylococcus aureus and Streptococcus pyogenes are the most common pathogens cultured from these sources

• Orbital cellulitis

  • Almost always arises from contiguous sinus infection because the walls of three sinuses make up portions of the orbital walls and infection can breach these walls or extend by way of a richly anastomosing venous system

  • The pathogenic agents are those of acute or chronic sinusitis—respiratory flora and anaerobes

  • S aureus is also frequently implicated

• The incidence of methicillin-resistant S aureus preseptal and orbital cellulitis has increased over the past several years

Clinical Findings

Symptoms and Signs

• Preseptal cellulitis

  • Presents with erythematous and edematous eyelids, pain, and mild fever

  • Vision, eye movements, and eye itself are normal

• Orbital cellulitis

  • Presents with signs of periorbital disease as well as proptosis (a protruding eye), restricted eye movement, and pain with eye movement

  • Fever is usually high

  • Decreased vision, restricted eye movements, and an afferent pupillary defect suggest diagnosis

Differential Diagnosis

• Primary or metastatic neoplasm of the orbi

• Orbital pseudotumor (idiopathic orbital inflammation)

• Orbital foreign body with secondary infection

Diagnosis

• CT scanning or MRI is required to establish the extent of the infection within the orbit and sinuses

Treatment

• Systemic antibiotics for preseptal and orbital cellulitis infection

• In conjunction with intravenous antibiotics and steroids, orbital infections may require surgical drainage for subperiosteal abscess

• Drainage of infected sinuses is often part of the therapy

Outcomes

Complications

• Preseptal cellulitis can progress to orbital cellulitis

• Orbital cellulitis can result in permanent vision loss due to compressive optic neuropathy

• Proptosis can cause corneal exposure, dryness, and scarring

• Severe orbital cellulitis can result in

  • Cavernous sinus thrombosis

  • Intracranial extension

  • Blindness

  • Death

Prognosis

• Most patients do well with timely treatment.

References