FIGURE 123.3 Desmarres lid retractors (A ) or eye lid speculum (B ) can be helpful in opening the eye lids if the child is unable or unwilling to open their eyes COMMON EYE EMERGENCIES Periorbital and Orbital Cellulitis CLINICAL PEARLS AND PITFALLS Periorbital cellulitis most often results from some form of soft tissue trauma or spread of local infection and can be managed with oral antibiotics targeting common skin flora Orbital cellulitis is a vision-threatening infection that is characterized by pain or limitation of eye movement, optic nerve involvement, and/or proptosis Distinguishing between periorbital and orbital involvement is often difficult based on clinical observations alone; imaging may play a critical role in the diagnosis Many cases of orbital cellulitis can be managed medically with intravenous (IV) antibiotics, whereas others may require surgical intervention Current Evidence The orbital septum is an extension of periosteum from the orbital bones that inserts into the tarsal plate of the upper and lower lids to form the anterior boundary of the orbital compartment Periorbital (or preseptal) cellulitis refers to infections limited to the soft tissues anterior to the orbital septum Disease processes posterior to the septum involve the contents of the orbit (e.g., fat, nerves, and extraocular muscles) and cause orbital (or postseptal) cellulitis Involvement of the orbit can threaten vision and potentially result in spread to the cavernous sinus and central nervous system (CNS) Periorbital infections are usually secondary to skin pathogens and most often result from eyelid trauma, insect bite, or contiguous spread of an infection, such as conjunctivitis (especially neonatal gonococcal conjunctivitis) or dacryocystitis Periorbital cellulitis can however also be caused by underlying sinusitis Orbital cellulitis is most often caused by extension of infection from adjacent sinuses (sinusitis is present in up to 98% of cases) Other etiologies include orbital trauma and surgery, and infections of the teeth, ear, or face Periorbital cellulitis requires treatment with antibiotics targeting gram-positive organisms since staphylococcal and streptococcal species are the most likely causes (Staphylococcus aureus and Streptococcus pyogenes predominate when infection arises from local skin trauma, whereas Streptococcus pneumoniae is commonly associated with sinusitis) While the same organisms are often involved in orbital cellulitis, nontypeable H influenzae and other gram-negative bacilli such as Moraxella catarrhalis are still important causes of orbital complications of acute bacterial sinusitis Anaerobes must also be considered when there is concern for sinusitis, an odontogenic source, or proven or suspected intracranial extension Goals of Treatment Accurate identification of periorbital versus orbital cellulitis is essential to proper treatment and a favorable clinical outcome Timely administration of appropriate antibiotics is critical in all cases Prompt recognition of symptoms and appropriate use of imaging allows for early diagnosis of orbital cellulitis, a potentially vision- and life-threatening condition Ophthalmology consultation is indicated in all cases of suspected or proven orbital cellulitis Surgical intervention may be required Otolaryngology consultation should be sought when there is concurrent sinonasal pathology FIGURE 123.4 Periorbital cellulitis in a child with eyelid swelling, erythema, and tenderness Clinical Considerations Clinical Recognition Both periorbital and orbital cellulitis are more often seen in children than adults Both conditions commonly present with fever, and periorbital erythema, pain, and swelling ( Fig 123.4 ) Any pediatric patient who presents with these findings requires careful examination to rule out orbital cellulitis The clinician should also recognize the signs of local and systemic spread of infection including visual disturbances, altered mental status, and sepsis Clinical Assessment The primary concern when making the diagnosis of periorbital cellulitis is to rule out the possibility of orbital cellulitis The cardinal signs of orbital cellulitis include decreased or painful eye movement, proptosis, changes in vision (e.g., change in acuity, decreased color vision, or visual field deficits), and papilledema (or other signs of optic nerve involvement such as Marcus Gunn pupil) Patients with orbital cellulitis may be irritable, toxic, and have a fever, but the presence of fever and leukocytosis are not sensitive enough markers to discriminate between the two conditions Due to the presence of the orbital septum which acts as a structural barrier, the eyelid swelling of orbital cellulitis typically does not extend beyond the superior orbital rim onto the brow The ED clinician should be aware that acute periorbital edema and erythema can also occur without infection Insect bites and allergic reactions can cause dramatic acute periorbital swelling, typically with minimal induration or tenderness, and oftentimes with pruritus These conditions are not usually associated with fever Often, close inspection of the skin with magnification can localize a site of an insect bite Swelling related to systemic allergic reactions is often bilateral, whereas periorbital cellulitis is rarely bilateral Underlying sinusitis can also cause periorbital swelling without cellulitis Conditions which may mimic some of the physical findings of orbital cellulitis include orbital tumors (e.g., rhabdomyosarcoma, neuroblastoma), orbital pseudotumor (an immune-mediated process), leukemia, and sickle cell crisis The best way to differentiate these mimickers of orbital cellulitis is with CT or MRI of the orbits and sinuses ... conditions commonly present with fever, and periorbital erythema, pain, and swelling ( Fig 123.4 ) Any pediatric patient who presents with these findings requires careful examination to rule out orbital