AUTHOR AND EDITOR INFORMATION

Section 1 of 12  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• Multimedia
• References

INTRODUCTION

Section 2 of 12  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• Multimedia
• References

Background

Infections of the orbit are uncommon, but they are potentially devastating infections that can quickly result in blindness, meningitis, or death. The emergency physician must make a rapid and accurate diagnosis and then quickly initiate therapy because visual loss is associated directly with the length of time to definitive treatment.

Pathophysiology

The orbit is a pyramid-shaped bony space in the anterior skull that contains the globe, the blood vessels, and the intraorbital muscles and nerves. The space is bordered on its superior, medial, and inferior sides by the facial sinuses (frontal, ethmoid and sphenoid, and maxillary, respectively). The bony septa separating the orbit from the sinuses are thin and fenestrated, particularly in the medial orbital wall, where the lamina papyracea borders the ethmoid sinus.

The anterior border of the orbit is marked by the orbital septum, a fibrous band from the external bony orbit to both eyelids, which effectively separates the preseptal space from the orbital space. This is actually contiguous with the periosteum that is reflected into the upper and lower lids. The posterior wall of the orbit contains the optic canal and the superior and inferior orbital fissures. The superior orbital fissure connects directly to the cavernous sinus and the intracranial space. The facial veins drain directly into the valveless superior and inferior ophthalmic veins. These, in turn, drain via many anastomoses into the cavernous sinus. The posterior wall is the source of the blood and nerve supply to the orbit.

The optic nerve (cranial nerve [CN] II) enters the orbit with the ophthalmic artery through the optic canal. CNs III, IV, and VI; the ophthalmic branch of the trigeminal nerve (CN V1); and the superior ophthalmic vein enter the cavernous sinus after exiting the orbit through the superior orbital fissure.

The superior ophthalmic vein provides the main venous drainage for the contents of the orbit. The smaller inferior ophthalmic vein exits the orbit through the inferior orbital fissure with the maxillary branch of the trigeminal nerve (CN V2) and connects with the temporal fossa.

Orbital infections develop via direct inoculation, extension from adjacent structures, and hematogenous spread. Sixty percent of these infections develop from the direct spread of sinusitis, most commonly ethmoidal.

Infections also can spread from the preseptal space, particularly from preseptal (or periorbital) cellulitis in children, as well as from the pharynx, middle ear, facial skin, nose, lacrimal gland (dacryocystitis), or dentition. The ease and rapidity of such infectious spread relates to the facial venous system, which has a great number of anastomoses and is entirely valveless.

Infectious material can be inoculated directly into the orbital soft tissue secondary to trauma, surgery, or orbital foreign bodies. More rarely, orbital infections develop from hematogenous seeding secondary to sepsis or bacterial endocarditis.

Orbital infections are classified by a 5-tier system, as described by Smith and Spencer and modified by Chandler et al.

• Group I - Preseptal cellulitis
• Group II - Orbital cellulitis
• Group III - Subperiosteal abscess
• Group IV - Orbital abscess
• Group V - Cavernous sinus thrombosis

This classification system does not necessarily imply an order of disease progression; however, it helps explain the physical signs and symptoms of the various infections and helps organize treatment plans. Preseptal (or periorbital) cellulitis, which is an inflammatory edema of the eyelids and periorbital skin with no involvement of the orbit, comprises the first group. Orbital signs (eg, chemosis, proptosis, visual loss) are not present in this infection. Because the facial veins are valveless, preseptal cellulitis may spread posteriorly to produce one of the intraorbital infections (groups II-V).

Orbital cellulitis is an infection of the soft tissue of the orbit without abscess formation. Patients with this infection may develop orbital signs and symptoms (eg, chemosis, visual loss), and they often have more systemic toxicity than patients with preseptal cellulitis. Direct orbit CT scan has increased in its sensitivity over the years for diagnosing this entity. Most cases will show edema with or without microabscesses. 

Orbital cellulitis may or may not progress to a significant subperiosteal abscess, orbital abscess, or cavernous sinus thrombosis.

Subperiosteal abscesses are collections of purulent material between the orbital bony wall and periosteum. This infection may develop from orbital cellulitis or from spread of an adjacent infection, as occurs when ethmoid sinusitis spreads to the medial orbital subperiosteal space. This diagnosis is confirmed by CT scan, but it can be suspected based on physical examination. In addition to signs of orbital involvement (eg, chemosis, visual loss), limitations of ocular motility and directional proptosis may be present from the intraorbital mass effect and entrapment of the extraocular muscles.

Orbital abscesses are collections of pus within the orbital soft tissue. Diagnosis is confirmed by CT scan, but the physical signs of severe exophthalmos and chemosis, with complete ophthalmoplegia, as well as venous engorgement or papilledema on funduscopic examination, are suggestive.

These infections usually are secondary to orbital cellulitis and sometimes can be differentiated from orbital cellulitis by the occurrence of the orbital apex syndrome. This syndrome is a collection of signs and symptoms consistent with organized infection in the posterior orbit (specifically, compression of the superior orbital fissure), and it is highly suggestive of group IV or V disease.

Signs include unilateral ptosis, proptosis, visual loss, internal and external ophthalmoplegia (ie, palsy of the pupillary and extraocular muscles), and CN V1 (forehead) anesthesia. Orbital cellulitis may or may not progress to cavernous sinus thrombosis.

Cavernous sinus thrombosis is an infectious thrombosis of the cavernous sinus. (The cavernous sinus, a circular venous structure surrounding the pituitary gland, drains blood from both orbits.) Infectious thrombosis most commonly is spread from the orbit via the valveless orbital veins into the cavernous sinus. Once again, this diagnosis is confirmed by CT scan or MRI; however, the physical sign of bilateral posterior orbital disease is highly suggestive.

Bilateral involvement occurs because the right and left ophthalmic veins drain into the same contiguous sinus. Since the cavernous sinus is connected through the midline and not differentiated into right and left, thrombosis of one side may thrombose the other side. Complete internal and external ophthalmoplegia often is produced when thrombosis of the sinus causes palsy of CNs III, IV, V1, and VI and the sympathetic fibers as they travel through prior to entry into the orbit.

The distinction between infectious thrombosis and orbital infection alone is important because the treatment of cavernous sinus thrombosis may involve the addition of anticoagulation therapy to the antibiotic therapy.

Intracranial infection or cavernous sinus thrombosis can result from any stage of orbital infections.

Mortality/Morbidity

• Cavernous sinus thrombosis
• Brain abscess or meningitis
• Permanent vision loss

Sex

Males are affected slightly more often than females.

Age

• Orbital infections are more common in persons younger than 19 years.
• Orbital infections are more severe in adults.

CLINICAL

Section 3 of 12  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• Multimedia
• References

History

History is directed at eliciting the source of infection, establishing risk factors for nonbacterial sources, and localizing the infection.

Chronologic relation with an insect sting, allergic reaction, or trauma may suggest etiologies that mimic an orbital infection. In particular, an allergic etiology is suggested by the lack of tenderness on physical examination and pruritus. 

Past medical history significant for HIV, diabetes, immunosuppression, steroid use, renal disease, and travel is important.

• Localizing the infection
• • Loss of eyesight - Orbit, cavernous sinus, or CNS
  • Vision loss can develop for any of the following reasons:
  • • Corneal damage secondary to proptosis or neurotrophic keratitis
    • Sustained elevated intraocular pressure
    • Thrombophlebitis of the ocular vasculature
    • Central retinal artery occlusion
    • Septic or inflammatory optic neuritis
  • Paresthesia of forehead - Posterior orbit, cavernous sinus, or CNS
  • Bilateral symptoms - Cavernous sinus or CNS
• Risk factors for nonbacterial disease
• • Insidious onset - Aspergillosis, tumor, syphilis, tuberculosis, and parasitic disease
  • History of HIV - Cryptococcosis, toxoplasmosis, tuberculosis, and syphilis
  • Diabetes mellitus or ketoacidosis - Consider fungal disease (Mucor or Rhizopus species) in any patient with elevated glucose, particularly in patients with diabetic ketoacidosis whose mental status does not improve with correction of their electrolyte abnormalities.
  • Travel (Asia, South America, eastern Europe) - Taenia solium (cysticercosis)
  • Travel (Australia, Mediterranean, Middle East) - Echinococcus granulosus
  • Leukemia, lymphoma, renal transplant, or deferoxamine therapy - Mucormycosis, aspergillosis
• Identifying the source of infection
• • Sinusitis
  • Preseptal cellulitis
  • Dental infection or tooth extraction
  • Otitis media
  • Surgeries, trauma, recent orbital fractures, lacerations, or foreign body
  • Pharyngitis
  • Animal or human bites and insect stings
  • Drugs - Immunosuppressants or steroids

Physical

The physical examination is directed toward localizing and identifying potential sources of infection.

Abnormal vital signs (eg, tachycardia, hyperpyrexia) favor an infectious etiology, whereas an insect bite, trauma, tumor, or allergy should be considered in a patient who is afebrile. However, orbital infection is not excluded from the differential by a normal temperature or vital signs.

Search for any signs of trauma (eg, raccoon eyes, Battle sign, clear rhinorrhea, fractures).

Search for a source of infection (eg, tenderness over sinuses, Pott puffy tumor, otitis, mastoiditis, dental abscesses, pharyngeal infection, abscesses) and check for meningeal signs.

Search nasal and oral mucosa for black necrotic tissue pathognomonic of mucormycosis, although this is a late sign. (Black eschar formation is secondary to the high predilection for Mucor hyphae to invade arterial walls and cause end-arterial necrosis.)

A cardiac examination may reveal a murmur of endocarditis.

In the eye examination, the main goal is to differentiate preseptal from orbital or cavernous sinus or intracranial infections.

Consider orbital disease in the presence of proptosis, decreased visual acuity, afferent pupillary defect, retinal venous engorgement, papilledema, chemosis, ptosis, or extraocular muscle motility disturbance.

• Preseptal - Group I
• • Lid edema, caused by an infection of subcutaneous tissue, is present. The edema is warm, tender, and taut.
  • Signs of orbital involvement (eg, proptosis, chemosis, visual impairment) are not present.
• Orbital cellulitis - Group II
• • Lid edema is secondary to a decrease in venous outflow (through the infected orbit); therefore, edema may be occasionally cool, doughy, and nontender.
  • The eyelids may be paralyzed secondary to infectious involvement of CN III, in contrast to preseptal cellulitis, in which the lids cannot be opened due to edema alone.
  • Orbital signs include chemosis, proptosis, and visual impairment.
  • Fever and leukocytosis
• Subperiosteal abscess - Group III
• • Directional proptosis - The globe is displaced away from the abscess.
  • The patient has limited ocular motility or pain on globe movement toward the abscess
  • Orbital signs include proptosis, chemosis, and visual impairment.
• Orbital abscess - Group IV
• • Severe proptosis
  • Severe internal and external ophthalmoplegia (palsy of the intraocular and extraocular muscles)
  • Systemic toxicity may be marked.
  • Orbital apex syndrome involves unilateral ptosis, proptosis, visual loss, internal and external ophthalmoplegia, and CN V1 anesthesia (forehead).
• Cavernous sinus thrombosis - Group V: Cavernous sinus thrombosis manifests with bilateral symptoms, bilateral orbital apex syndrome, ophthalmoplegia, proptosis, and corneal hypesthesia.
• Intracranial spread manifests with meningeal signs and changes in mental status.

Causes

Bacteria cause the vast majority of orbital infections. The incidence of Haemophilus influenzae type B has decreased since the widespread use of the HiB vaccine in 1991. No doubt the virulence of this organism is extremely high as reflected by the high incidence of bacteremia and meningitis. In contrast to this agent, bacteremia occurs today in less than 2% of patients with orbital cellulitis.

Likewise, the recent recommendations to expand the use of the pneumococcal vaccination in infants have decreased this pathogen. Leading pathogens now include Staphylococcus aureus and Streptococcus species. Of significance, the incidence of methicillin-resistant S aureus (MRSA) is dramatically increasing. A recent study in Houston shows that MRSA now represents over 75% of all community-acquired S aureus cases. In the same study, the majority of the patients with orbital cellulitis had MRSA as the pathogen. 

Fungal infections are less common than bacterial infections and occur more commonly in patients who are immunocompromised (eg, those with HIV or diabetes).

Parasitic diseases are practically nonexistent in the US; however, in endemic areas (eg, Mediterranean, eastern Africa, Australia, Middle East, Asia, South America, eastern Europe) and in travelers to these areas, such infections are not uncommon.

• Bacterial
• • S aureus (MSSA and MRSA usually from skin violation)
  • Streptococcus pneumoniae and Group A(usually from sinusitis and skin violation, respectively))
  • H influenzae (usually non typeable)
  • Enterobacteriaceae (eg, Proteus and Klebsiella species, Escherichia coli)
  • Anaerobes (eg, Bacteroides and Fusobacterium species)
  • Pseudomonas species, Eikenella corrodens
  • Peptostreptococcus species
  • Mycobacterium species
  • Treponema pallidum (syphilis)
• Fungal
• • Phycomycetes (eg, Rhizopus, Mucor, Absidia species)
  • Ascomycetes, such as Aspergillus (indolent onset, high mortality) and Bipolaris species.
  • Cryptococcus species
• Parasites
• • E granulosus
  • T solium
  • Trichinella spiralis
  • Onchocerca species
• Protozoa (eg, Toxoplasma gondii)

DIFFERENTIALS

Section 4 of 12  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• Multimedia
• References

Other Problems to be Considered

Allergic reaction
Grave ophthalmopathy
Nephrotic syndrome
Benign intracranial hypertension (pseudotumor cerebri)
Orbital hematoma

WORKUP

Section 5 of 12  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• Multimedia
• References

Lab Studies

• Complete blood count (CBC) with differential
• Blood cultures
• • Recent literature shows a yield of 0-2% in patients with orbital cellulitis and may not be indicated in the immunized patient.
  • Minimally invasive culture techniques such as nasal swabs or eye discharge cultures yield a higher percentage of positive cultures than do blood cultures.
  • Elevated serum glucose level
• Ketoacidosis or electrolyte abnormalities should be rapidly corrected.
• Arterial blood gas (ABG) in debilitated patients or in patients with elevated blood glucose level

Imaging Studies

• CT scan - Orbit, sinuses, and frontal lobe
• • Immediately obtain a CT scan of the orbit, sinus, and head for every patient showing signs of orbital involvement. Of note, recent literature shows that the radiation exposure of routine CT scans may increase the prevalence of cancer-induced mortality over a lifetime to 0.1%. New recommendations are to keep the radiation doses as low as possible, especially in the pediatric patient.   
  • If a brain abscess is suspected or if the patient has HIV, consider a head CT scan to exclude mass lesions before performing a lumbar puncture (LP).
  • Contrast is not helpful for intraorbital disease.
• MRI may improve visualization of cavernous sinus thrombosis.
• B-scan ultrasonography of the orbit can miss posterior abscesses.

Other Tests

• Fiberoptic nasopharyngeal endoscopy: If any suspicion of mucormycosis (ie, elevated blood glucose, leukemia, renal disease, deferoxamine therapy) exists, fiberoptic nasopharyngeal endoscopy should be performed (usually, by an otolaryngologist) to seek evidence of black eschar formation.
• Slit-lamp examination
• Rapid plasma reagin (RPR), particularly in cases of insidious onset or with a history of syphilis
• In clinical exams is suggestive of meningitis, cerebrospinal fluid (CSF) analysis for gram stain, cell count, cultures, and antigens

TREATMENT

Section 6 of 12  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• Multimedia
• References

Emergency Department Care

• Adults with preseptal cellulitis and no signs of orbital involvement can be discharged on oral antibiotics with close follow-up care.
• • Admit adults with orbital signs and quickly initiate IV antibiotics or antifungals and, if necessary, surgical intervention.
  • Admit all children and initiate therapy, even if they lack orbital signs, because children are deficient in IgG2 and are predisposed to bacteremia.
• For orbital cellulitis, oxacillin or nafcillin can be used with the addition of ampicillin and sulbactam in children to cover H influenzae. Note the increasing rate of community-acquired MRSA organisms. In many centers, this has become the leading organism. No literature shows that this is a more virulent organism than others; however, the danger is in its lack of susceptibility to most antibiotics. 
• • Alternatively, a cephalosporin (eg, cefuroxime, cefoxitin, cefotetan) can be used alone.
  • Nasal decongestants can be used to help drain the sinuses.
• Surgical drainage generally is not necessary for cellulitis; however, any patient with compromised vision (20/60 or worse), well-defined abscess, or complete ophthalmoplegia should receive immediate surgery for drainage and debridement.
• • Consider surgical drainage of abscesses (orbital or subperiosteal) without visual loss. Consider drainage of sinuses as well.
  • Some patients can be monitored for 48 hours on IV antibiotics, with surgery performed for increasing proptosis, worsening visual acuity, or isolated muscle weakness. Surgery is performed after 48 hours fever continues or antibiotics fail.
  • Several studies have shown successful drainage of a subperiosteal abscess by endoscopy, which avoids an external incision.

Consultations

• Ophthalmologists
• Infectious disease specialists
• Otolaryngologists

MEDICATION

Section 7 of 12  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• Multimedia
• References

Drug therapy consists of antibiotics, antifungals, and nasal decongestants.

Drug Category: Antibiotics

Therapy must cover all likely pathogens in this clinical setting.

Drug Category: Nasal decongestants

Used to reduce intranasal congestion.

Drug Category: Antifungals

Imidazole derivatives that exert a fungicidal effect by altering the permeability of fungal cell membranes.

FOLLOW-UP

Section 8 of 12  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• Multimedia
• References

Further Inpatient Care

• Correct underlying disorders, if present (eg, hyperglycemia, acidosis, infection, immunosuppression).

Complications

• Cavernous sinus thrombosis
• Brain abscess or meningitis
• Visual loss

Prognosis

• Risk of visual loss (10-33%)
• Cavernous sinus thrombosis (80% mortality)
• Intracranial involvement (20-40% mortality)

MISCELLANEOUS

Section 9 of 12  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• Multimedia
• References

Medical/Legal Pitfalls

• Orbital infection not in differential diagnosis: Failure to consider the diagnosis is the most common medicolegal error.
• Delaying antibiotics and surgery: Patients with orbital infections do not need extraneous radiographs and laboratory tests; they need antibiotics and/or antifungals, immediate CT scan, and surgery.
• Delayed consultation: Orbital infections are a medical emergency; consultation with an otolaryngologist cannot be delayed.

ACKNOWLEDGMENTS

Section 10 of 12  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• Multimedia
• References

The authors and editors of eMedicine gratefully acknowledge the contributions of previous author, Robert G Hendrickson, MD, to the development and writing of this article.

MULTIMEDIA

Section 11 of 12  

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• Multimedia
• References

Media file 1:  Complications of orbital infections. Brain abscess in a young man secondary to an orbital infection from Mucor species.
	View Full Size Image
Media type:  MRI

Media file 2:  Orbital infections. Orbital abscess with significant proptosis.
	View Full Size Image
Media type:  CT

Media file 3:  Orbital infections. Subperiosteal abscess with contiguous sinusitis.
	View Full Size Image
Media type:  MRI

Media file 4:  Orbital infections. Subperiosteal abscess with contiguous sinusitis.
	View Full Size Image
Media type:  MRI

Media file 5:  Orbital infections. Frontal sinusitis.
	View Full Size Image
Media type:  MRI

Media file 6:  Orbital infections. Orbital abscess with significant proptosis.
	View Full Size Image
Media type:  CT

REFERENCES

Section 12 of 12

• Authors and Editors
• Introduction
• Clinical
• Differentials
• Workup
• Treatment
• Medication
• Follow-up
• Miscellaneous
• Acknowledgments
• Multimedia
• References

• Ambati BK, Ambati J, Azar N. Periorbital and orbital cellulitis before and after the advent of Haemophilus influenzae type B vaccination. Ophthalmology. Aug 2000;107(8):1450-3. [Medline].
• Donahue SP, Schwartz G. Preseptal and orbital cellulitis in childhood. A changing microbiologic spectrum. Ophthalmology. Oct 1998;105(10):1902-5; discussion 1905-6. [Medline].
• Farnath D. Ocular infections. In: Infectious Disease in Emergency Medicine. 2^nd ed. 1998:843-58.
• Freidlin J, Acharya N, Lietman TM, Cevallos V, Whitcher JP, Margolis TP. Spectrum of eye disease caused by methicillin-resistant Staphylococcus aureus. Am J Ophthalmol. Aug 2007;144(2):313-5. [Medline].
• Ghezzi K, Renner GS. Ophthalmologic disorders. In: Emergency Medicine. Concepts and Clinical Practice. 1992:2427-59.
• Gordon LK. Diagnostic dilemmas in orbital inflammatory disease. Ocul Immunol Inflamm. Mar 2003;11(1):3-15. [Medline].
• Hendrickson RG, Olshaker J, Duckett O. Rhinocerebral mucormycosis: a case of a rare, but deadly disease. J Emerg Med. Jul-Aug 1999;17(4):641-5. [Medline].
• Kraus DJ, Bullock JD. Orbital infections. In: Pepose JS, Holland G, Wilheimus K, eds. Ocular Infection and Immunity. Mosby-Year Book; 1996:1321-40.
• McKinley SH, Yen MT, Miller AM, Yen KG. Microbiology of pediatric orbital cellulitis. Am J Ophthalmol. Oct 2007;144(4):497-501. [Medline].
• Mills DM, Tsai S, Meyer DR, Belden C. Pediatric ophthalmic computed tomographic scanning and associated cancer risk. Am J Ophthalmol. Dec 2006;142(6):1046-53. [Medline].
• Rumelt S, Rubin PA. Potential sources for orbital cellulitis. Int Ophthalmol Clin. Summer 1996;36(3):207-21. [Medline].
• Wald ER. Periorbital and orbital infections. Infect Dis Clin North Am. Jun 2007;21(2):393-408, vi. [Medline].
• Westfall CT, Shore JW, Baker AS. Orbital infections. In: Infectious Diseases. 2^nd ed. 1373-7.
• Yohai RA, Bullock JD, Aziz AA, Markert RJ. Survival factors in rhino-orbital-cerebral mucormycosis. Surv Ophthalmol. Jul-Aug 1994;39(1):3-22. [Medline].
• Younis RT, Anand VK, Davidson B. The role of computed tomography and magnetic resonance imaging in patients with sinusitis with complications. Laryngoscope. Feb 2002;112(2):224-9. [Medline].

Article Last Updated: Dec 22, 2007