Infections

Ocular Infections & Inflammation: Overview

The eyelids, conjunctiva, cornea, lacrimal system, and orbit are all potential sites of infection. As an oculoplastic surgeon, Dr. Brown evaluates and manages the full spectrum of periocular infections — from common conditions such as blepharitis and allergic conjunctivitis to serious, vision-threatening infections such as orbital cellulitis and orbital abscess. Accurate diagnosis is essential, because the distinction between a superficial lid infection and a deep orbital infection determines whether a patient is managed outpatient with oral antibiotics or admitted urgently for intravenous therapy and possible surgery.

Blepharitis

Blepharitis is one of the most common eyelid conditions seen in oculoplastic practice. It is a chronic inflammation of the eyelid margins that affects the base of the eyelashes and, in the posterior form, the meibomian oil glands. While blepharitis is rarely dangerous, it causes significant daily discomfort and, when poorly controlled, can contribute to recurrent chalazia, corneal irritation, and dry eye disease.

Two Forms of Blepharitis

• Anterior blepharitis affects the outer front of the lid margin where the lashes attach. It is most commonly caused by Staphylococcus aureus overgrowth or seborrheic dermatitis (dandruff). Collarettes — waxy, sleeve-like debris around individual lashes — are the characteristic finding of staphylococcal blepharitis.
• Posterior blepharitis (meibomian gland dysfunction, MGD) affects the inner lid margin and the row of meibomian gland orifices just behind the lashes. The glands produce an abnormally thick, inspissated oil that cannot flow freely, disrupting the tear film and causing evaporative dry eye. Acne rosacea and seborrheic dermatitis are common underlying associations.

Symptoms

• Burning, gritty, or foreign-body sensation
• Morning crusting or “gluing” of the lashes
• Redness and swelling of the lid margins
• Intermittent blurred vision that clears with blinking (unstable tear film)
• Excessive tearing or, paradoxically, dry eye symptoms

Treatment

Blepharitis is a chronic condition that is controlled rather than cured. The cornerstone of treatment is daily lid hygiene: warm compresses applied for several minutes soften inspissated meibomian secretions, followed by gentle lid margin scrubs using a dilute baby shampoo solution or commercially available lid wipes. For moderate-to-severe posterior blepharitis, a four-to-eight-week course of oral doxycycline at anti-inflammatory doses (50–100 mg daily) reduces meibomian gland inflammation and significantly improves symptoms. Topical azithromycin gel applied to the lid margin is an alternative. Patients with associated rosacea benefit from treating that condition concurrently.

Allergic Conjunctivitis

Allergic conjunctivitis is an IgE-mediated hypersensitivity reaction of the conjunctiva to an environmental allergen. It is among the most prevalent ocular conditions in the United States, affecting an estimated 20% of the population. Unlike infectious conjunctivitis, allergic conjunctivitis is not contagious.

Seasonal vs. Perennial

• Seasonal allergic conjunctivitis (SAC) is the most common form and is triggered by airborne pollens from trees, grasses, and weeds. Symptoms are worst during spring and fall when pollen counts peak.
• Perennial allergic conjunctivitis (PAC) persists throughout the year and is driven by indoor allergens such as dust mites, pet dander (not the hair itself, but the protein-containing dander and saliva), and mold spores. Symptoms may be milder but are continuous.

Symptoms

• Intense bilateral itching — the hallmark symptom that distinguishes allergic from infectious conjunctivitis
• Watery, clear discharge
• Conjunctival redness and chemosis (conjunctival swelling)
• Eyelid swelling
• Associated nasal congestion, sneezing, or skin hives in sensitized individuals

Treatment

Allergen avoidance is the first step. Topical dual-action antihistamine/mast-cell stabilizer drops — such as olopatadine or ketotifen — are the most effective first-line medications and can be used once or twice daily during allergy season. Cold compresses reduce acute lid and conjunctival swelling. Systemic antihistamines provide additional relief. In severe or refractory cases, a brief course of topical corticosteroids (under ophthalmologic supervision) or referral for allergen immunotherapy may be considered. Frequent eye rubbing should be discouraged because it releases more histamine from mast cells, perpetuating the itch-rub cycle and risking corneal damage over time.

Preseptal and Orbital Cellulitis

Periorbital infections are classified based on their relationship to the orbital septum — the thin fibrous diaphragm that extends from the orbital rim into the eyelid. This anatomic boundary is the single most important determinant of urgency and management. Infection anterior to the septum (preseptal) is common and generally safe to treat with oral antibiotics; infection posterior to the septum (orbital) is serious, requires hospitalization and intravenous antibiotics, and may threaten vision and life if not promptly controlled.

Preseptal Cellulitis

Preseptal cellulitis (also called periorbital cellulitis) is an infectious inflammation of the eyelid and periocular soft tissues anterior to the orbital septum. The infection does not involve the orbit itself.

Causes

• Skin trauma — insect bites, lacerations, or abrasions that introduce skin flora
• Spread from a hordeolum, chalazion, or dacryocystitis
• Upper respiratory infection with secondary spread (particularly in young children)
• Common organisms: Staphylococcus aureus, Streptococcus pyogenes, and, in unvaccinated children, Haemophilus influenzae type b

Key Clinical Features

• Eyelid erythema, warmth, and swelling
• Normal extraocular motility, normal pupil reactions, and normal visual acuity — these three findings distinguish preseptal from orbital cellulitis
• No proptosis

Treatment

• Older children and adults with mild-to-moderate disease: oral antibiotics (amoxicillin-clavulanate/Augmentin) with close outpatient follow-up within 24–48 hours
• Children under age 5, patients who appear systemically ill, or patients who fail outpatient treatment: hospital admission for intravenous antibiotics
• A localized abscess identified clinically or on CT requires incision and drainage
• CT imaging is obtained when orbital cellulitis cannot be clinically excluded or when the patient is not improving

Orbital Cellulitis

Orbital cellulitis is a true surgical emergency. It is defined as infection of the orbital fat and soft tissues posterior to the orbital septum. Ninety percent of cases arise from direct extension of acute bacterial sinusitis, particularly ethmoid sinusitis, through the thin lamina papyracea (medial orbital wall). Less common sources include orbital trauma, prior surgery, dental infections, and dacryocystitis.

Symptoms and Signs

• Fever, malaise, and toxicity
• Painful limitation of extraocular movements — a critical distinguishing feature from preseptal cellulitis
• Proptosis (forward displacement of the globe)
• Chemosis (conjunctival swelling)
• Decreased visual acuity or an afferent pupillary defect signal impending optic nerve compromise and require urgent surgical decompression

Evaluation

CT imaging of the orbit and paranasal sinuses with contrast is the standard of care and is obtained urgently. CT identifies the extent of orbital involvement, confirms or excludes sinus disease, detects foreign bodies in trauma cases, and most importantly identifies subperiosteal or intraorbital abscess that requires surgical drainage.

Treatment

• Hospital admission and broad-spectrum intravenous antibiotics covering gram-positive cocci, gram-negative rods, and anaerobes
• Intravenous antibiotic therapy is continued for 7–10 days, followed by oral antibiotics for 10–14 additional days
• Infectious disease consultation is obtained for complex or non-responding cases
• Surgical drainage — of the orbit and affected sinuses — is performed when a subperiosteal or intraorbital abscess is identified or when the patient fails to improve within 24–48 hours on appropriate antibiotics
• Cavernous sinus thrombosis is a rare but life-threatening complication characterized by rapid progression of proptosis, bilateral eye involvement, and neurologic signs; it requires urgent neurosurgical consultation and anticoagulation consideration

Herpes Zoster Ophthalmicus (Shingles)

Herpes zoster ophthalmicus (HZO) is reactivation of the varicella-zoster virus (VZV) — the same virus that causes chickenpox — within the first division (ophthalmic branch, V1) of the trigeminal nerve. After the primary chickenpox infection, VZV becomes latent in the trigeminal ganglion. Decades later, when immunity wanes, the virus can reactivate and travel down the nerve to the skin and eye. HZO accounts for approximately 10–20% of all cases of shingles and has the potential to cause serious ocular complications, including corneal scarring, uveitis, glaucoma, and vision loss.

Risk Factors for Reactivation

• Advanced age — incidence rises sharply after age 60
• Immunosuppression from HIV, organ transplantation, cancer chemotherapy, or immunosuppressive medications
• Significant physical or emotional stress

Symptoms and Signs

• Prodrome: burning, tingling, or shooting pain along the forehead and scalp — often appearing 1–4 days before any skin findings
• Rash: erythematous papules that rapidly evolve into fluid-filled vesicles in a dermatomal distribution on one side of the forehead, upper eyelid, and sometimes the tip or side of the nose
• Hutchinson’s sign: vesicles on the tip or side of the nose indicate involvement of the nasociliary nerve — the branch that also supplies the eye — and substantially increases the risk of ocular complications
• Ocular involvement: conjunctivitis, keratitis (corneal inflammation), uveitis, elevated intraocular pressure, and, rarely, acute retinal necrosis

Treatment

Antiviral therapy started within 72 hours of rash onset significantly reduces the severity, duration, and incidence of postherpetic neuralgia. Oral valacyclovir (1 g three times daily for 7 days) or famciclovir are preferred. Patients with moderate-to-severe ocular involvement may require adjunctive topical corticosteroid drops under close monitoring. Postherpetic neuralgia — persistent nerve pain lasting months to years after the rash heals — is the most debilitating long-term complication and may be addressed with tricyclic antidepressants, gabapentin, or topical lidocaine patches.

Lacrimal (Tear System) Infections

The lacrimal drainage system — comprising the puncta, canaliculi, lacrimal sac, and nasolacrimal duct — can become obstructed and subsequently infected at any level. As an oculoplastic surgeon, Dr. Brown has specialized training in the surgical management of these conditions.

Dacryocystitis

Dacryocystitis is an infection of the lacrimal sac, the reservoir that collects tears from the canaliculi before they drain through the nasolacrimal duct into the nose. It develops when nasolacrimal duct obstruction causes static tears to pool and become infected. Patients typically present with a painful, red, and swollen mass at the inner corner of the lower eyelid (medial canthus), accompanied by tearing and purulent discharge from the punctum. Pressing over the lacrimal sac often expresses pus back through the punctum.

Acute vs. Chronic Dacryocystitis

• Acute dacryocystitis presents with sudden, significant pain, redness, and swelling at the medial canthus. Treatment is oral or intravenous antibiotics (amoxicillin-clavulanate, cephalexin). A fluctuant abscess is incised and drained. Probing the nasolacrimal duct is avoided during active infection. Most patients with acute dacryocystitis will ultimately require dacryocystorhinostomy (DCR) once the acute infection has resolved, because the underlying duct obstruction persists.
• Chronic dacryocystitis presents with persistent tearing and mucoid or mucopurulent discharge without the acute inflammatory signs. A distended, minimally tender lacrimal sac is characteristic. Definitive treatment is surgical: a dacryocystorhinostomy (DCR) creates a new bypass drainage passage from the lacrimal sac directly into the nasal cavity, eliminating the obstruction and curing the infection.

Dacryocystorhinostomy (DCR)

DCR is the gold-standard surgical procedure for obstructed nasolacrimal duct with chronic tearing and dacryocystitis. Dr. Brown performs DCR through either an external incision (external DCR, which has the highest long-term success rate) or an endoscopic intranasal approach. Fine silicone tubes are placed through the new opening during surgery and removed in the office approximately 3 months later. DCR eliminates both the tearing and the recurring infections caused by nasolacrimal obstruction.

Canaliculitis

Canaliculitis is infection of the canaliculus (the small channel connecting the punctum to the lacrimal sac). It is less common than dacryocystitis and is often misdiagnosed as chronic conjunctivitis. The most common causative organism is Actinomyces israelii, a filamentous bacterium. Classic findings include a chronically red and swollen punctum that discharges sulfur granules (small yellow-white concretions) when expressed. Treatment is irrigation with penicillin solution and, for persistent cases, curettage of the concretions through the punctum.

Dacryoadenitis

Dacryoadenitis is inflammation of the lacrimal gland, located in the superolateral orbit beneath the outer third of the upper eyelid. Acute dacryoadenitis presents with pain, tenderness, and swelling of the outer portion of the upper eyelid, producing an S-shaped lid contour. It may be caused by bacterial infection (often Staphylococcus or Streptococcus) or by viral illness (mumps, Epstein-Barr virus, or herpes zoster). Chronic dacryoadenitis — painless lacrimal gland enlargement — raises the differential of systemic diseases including sarcoidosis, Sjögren’s syndrome, IgG4-related disease, lymphoma, and benign lymphoid hyperplasia, and requires biopsy in most cases.

Orbital Infections

Orbital infections — those posterior to the orbital septum — are among the most serious conditions managed in oculoplastic surgery. They require urgent evaluation, CT imaging, hospital admission, and often surgical intervention.

Pathophysiology

The orbit communicates with the paranasal sinuses through thin bony walls, particularly the lamina papyracea (the paper-thin medial wall separating the orbit from the ethmoid sinuses). Acute bacterial sinusitis can erode through this barrier, allowing infection to enter the orbital space. Less commonly, orbital infection follows eyelid or facial trauma, orbital fracture repair, dacryocystitis, dental infection, or spread from a systemic source.

Chandler Classification

Mucormycosis

Mucormycosis is a rare but fulminant fungal infection of the sinuses and orbit caused by fungi of the order Mucorales (Zygomycetes). It occurs almost exclusively in patients with diabetic ketoacidosis, prolonged neutropenia, or severe immunosuppression. The fungal hyphae invade blood vessel walls, causing thrombosis and ischemic necrosis of surrounding tissue. Infection begins in the nasal cavity and paranasal sinuses, then spreads rapidly through the orbit toward the brain. Signs include facial pain, black eschar on the palate or nasal mucosa, ophthalmoplegia, and vision loss. Treatment requires aggressive surgical debridement of all infected tissue — which may include orbital exenteration — combined with high-dose systemic amphotericin B and correction of the underlying metabolic or immune deficiency. Hyperbaric oxygen therapy is used as adjunctive treatment.

Orbital Abscess

An orbital abscess is a collection of pus within the orbital space. It may form as a subperiosteal abscess (between the periorbita and the orbital wall) or as an intraorbital abscess (within the orbital fat itself). Subperiosteal abscess is the more common form and most often occurs medially at the lamina papyracea, adjacent to infected ethmoid sinuses.

Clinical Presentation

• High fever and systemic toxicity
• Severe restriction of eye movement, often with pain on attempted gaze
• Significant proptosis, frequently with downward and outward displacement of the globe in medial subperiosteal abscess
• Worsening despite intravenous antibiotics is the clearest indication for surgical intervention

Surgical Management

CT imaging guides the surgical approach. Medial or inferomedial subperiosteal abscesses can often be drained endoscopically through the nose without an external incision. Superior or lateral orbital abscesses require an external approach through a lid crease or brow incision. Concurrent sinus drainage is performed by an otolaryngologist when the sinuses are the source. Prompt and complete drainage is essential to prevent further progression, optic nerve damage, and intracranial extension.

Complications of Untreated or Delayed Orbital Infection

• Permanent visual loss from optic nerve compression or corneal exposure
• Cavernous sinus thrombosis with potential meningitis and intracranial abscess
• Orbital apex syndrome (combined ophthalmoplegia and vision loss from apical involvement)
• Death in severe cases, particularly with mucormycosis or cavernous sinus thrombosis