Preceptal /Orbital Cellulitis & Cavernous Sinus Thrombosis

Preseptal vs. Orbital Cellulitis:
· Both occur most commonly in children; orbital cellulitis is less common, but much more serious
· In both preseptal and orbital cellulitis, the lids are red and swollen. The lids may be swollen shut, but it is essential to examine the eye to evaluate visual acuity and extraocular movement

Preseptal (periorbital) Cellulitis:
· an infection lying anterior to the orbital septum: only the lids, not the orbit
· associated with swelling of the eyelid, discoloration of the orbital skin, redness, and warmth
· usually results from direct extension of contiguous skin infection (pustular or skin abrasions) or trauma; less commonly from sinusitis
· Vision, extraocular movements, pupillary findings, and optometric examination findings are normal, and there is no proptosis.
· Most common organisms are strep (esp strep pneumo), staph aureus and H. Flu
· Diagnosis of preseptal cellulitis should be based on history and clinical exam; however in it can be difficult to distinguish from orbital cellulitis, and may necessitate a CT scan in certain cases. Indications for a CT to rule-out orbital cellulitis include:
o   Inability to accurately assess vision
o   Gross proptosis, ophthalmoplegia, bilateral edema, or deteriorating visual acuity
o   No improvement despite 24 hours of intravenous antibiotics
o   Signs or symptoms of CNS involvement
· Outpatient treatment with oral abx and close observation is appropriate: empiric  coverage for above organisms (augmentin or cefpodoxime +/- MRSA coverage) x 7-10 days

Orbital (or postseptal) Cellulitis:
· similar but more severe symptoms than preseptal cellulitis
· localized posterior to the orbital septum, involves the soft tissues and bone of the orbit
· patients may have proptosis, decreased ocular mobility, ocular pain, and tenderness on eye movement; retro-orbital gas or abscess formation increases the severity of these findings and results in decreased visual acuity
· Proptosis may not be grossly apparent and should be measured (e.g., with an exophthalmometer); a difference of 2 mm or more is significant
· Fever and leukocytosis are usually present in children, but they may be absent in adults.
· 80-90% of cases occur with preexisting sinus infections (ethmoid is most common).  Less common causes include orbital surgery, facial fractures, dacrocystitis, dental infections secondarily infected nasal tumor as etiologies.
· Microbiology: similar to preseptal cellulitis (strep, staph and H. Flu, + anaerobes)
· Diagnosis: should be confirmed with imaging (CT or MRI), and to evaluated extent of retro-orbital involvement
· Treatment: hospitalization, IV antibiotics (broad-spectrum coverage of H. flu, staph, strep and anaerobes), and, in some cases, incision and drainage.  Management should be done in conjunction with ENT and ophthalmology consultation.  
· Complications of orbital cellulitis can include: localized abscesses or extension intracranially, causing intracranial abscess, meningitis, or cavernous sinus thrombosis
· Ddx of bacterial orbital cellulitis includes malignancy, invasive fungal disease (ie. invasive sinus aspergillosis and mucormycosis) and orbital pseudotumor (an idiopathic cause of painful opthalmoplegia with inflammatory proptosis)

Cavernous Sinus Thrombosis: a serious complication of orbital cellulitis, and other facial infections (as the blood supply is from the facial/ophthalmic veins)

• clinical presentation is due to the venous obstruction as well as impairment of the cranial nerves that are run through/along the cavernous sinus
• Headache is the most common symptom and usually precedes fevers, periorbital edema, and cranial nerve signs.
• Periorbital edema and chemosis result from occlusion of the ophthalmic veins.
• Lateral gaze palsy (isolated cranial nerve VI) is usually seen first since CN VI lies freely within the cavernous sinus, in contrast to CN III and IV, which lie within the lateral walls of the sinus.
• Ptosis, mydriasis, and eye muscle weakness from cranial nerve III dysfunction
• Manifestations of increased retrobulbar pressure follow: exophthalmos, ophthalmoplegia, sluggish pupils, decreased visual acuity (increased IOP on optic nerve and central retinal artery)
• Hypoesthesia or hyperesthesia in V1 and V2 branches of the cranial nerve V
• Signs and symptoms in the contralateral eye is diagnostic of CST, although the process may remain confined to one eye.
• Meningeal signs or systemic signs indicative of sepsis are late findings

(Victoria Kelly MD, 5/24/11)