Orbital Infections

Mucormycosis

• Mucormycosis is a fulminant oportunisitic fungal infection caused by fungi of the class Zygomycetes.
• PredisORALsing factors: patients who have diabetic ketoacidosis or who are immunocompromised
• Etiology: Infection begins in the paranasal sinuses and spreads to the orbit. The large, nonseptate hyphae cause vascular occlusion. This causes ischemia and infarction of tissue.
• Therapy: includes correction of the underlying metabolic abnormality and debridement of all involved infected tissue. It could require orbital and sinus exenteration, coupled with both systemic and local treatment with Amphotericin B
• Adjunct therapy: hyperbaric oxygen therapy could be beneficial

Orbital cellulitis

• infectious inflammatory process involving the orbital tissues posterior to the orbital septum and requires
• Etiologies include trauma, orbital fracture repair, strabismus surgery
• Extension of pre-existing infections of the face, lacrimal sac, and lacrimal gland which can extend into the orbit
• Pathophysiology: The most common bacterial pathogens in preseptal cellulitis include Haemophilus influenza, Staphylococcus aureus, and Streptococcus pneumoni
• Therapy: Subperiosteal abscess formation should be suspected if patients fail to improve or deteriorate on intravenous antibiotics .
  • Infants with preseptal cellulitis are usually admitted for intravenous therapy, whereas
  • older children and adults with preseptal infections could be treated with oral antibiotics. 7- to 10-days of intravenous therapy are required, followed by a course of oral antibiotics for 10 to 14 days
• infection posterior to orbital septum
• 90% from extension of acute or chronic bacterial sinusitis, remainder s/p trauma or surgery or 2^o to extension from other orbital or periorbital infection, or endogenous w/septic embolization
• fever, proptosis, restriction of EOM’s, pain on globe movement
• decreased visual acuity Afferent Pupillary Defect (APD), prolonged high Intraocular pressure (IOP) can be indications for aggressive management to prevent orbital apex syndrome or cavernous sinus thrombosis

• CT of orbit and sinuses to confirm sinus disease, rule out mass, rule out orbital foreign body if h/o trauma (even remote), rule out orbital or subperiosteal abscess which will require surgical drainage
• blood culture then broad spectrum IV antibiotics to cover gram cocci, H. influenzae (although less prevalent in kids 2^o to immunization), anaerobes, typically nafcillin and 3rd generation cephalosporin; ID consult if necessary; kids more often single organism
• progression of infection or no daily improvement on appropriate antibiotics can mean abscess: repeat CT as needed (prn) and drain w/concomitant sinus drainage as needed (prn)
• cavernous sinus thrombosis: rapid progression of proptosis and neurologic signs of intracranial dysfunction; could lead to meningitis; get neurosurgery consult