Eye pain can be a symptom of various ocular conditions, ranging from benign to sight-threatening issues. A thorough assessment of the characteristics of the pain and associated symptoms is crucial in forming a differential diagnosis. Here’s a detailed exploration of potential causes for eye pain:

1. Conjunctivitis:
• Often presents with a gritty or itchy sensation, redness, and discharge that can be watery, mucoid, or purulent.
• Pain is usually mild but present alongside other symptoms like redness and discharge.
• Keratitis:
• Characterized by intense photophobia, pain, and watering.
• Circumlimbal injection and corneal infiltrates may indicate bacterial, viral, or fungal etiology.
• Risk factors include contact lens use, trauma, or exposure to UV light.
• Corneal Abrasion:
• Presents with sharp pain, foreign body sensation, and watering.
• Diagnosis is confirmed with fluorescein staining, revealing an epithelial defect.
• Common in contact lens wearers or post-trauma.
• Anterior Uveitis:
• Involves photophobia, pain, and redness, often with blurred vision.
• Examination may show keratic precipitates (KPs) and anterior chamber (AC) cells and flare.
• It may be associated with systemic inflammatory conditions.
• Scleritis:
• Severe, deep, boring eye pain that can radiate to the face and head.
• Associated with diffuse deep injection that does not blanch with vasoconstrictors.
• Often related to systemic autoimmune diseases.
• Episcleritis:
• Mild discomfort with sectoral redness that blanches with topical vasoconstrictors.
• Typically not associated with systemic disease and self-limiting.
• Acute Angle-Closure Glaucoma:
• Severe ocular pain with headache, nausea, and vomiting, often with blurred vision and halos around lights.
• Examination may reveal elevated intraocular pressure, corneal edema, and a mid-dilated pupil.
• Endophthalmitis:
• Presents with severe pain, visual loss, redness, and purulent discharge.
• History of recent eye surgery or trauma may be elicited.
• This is an ophthalmic emergency requiring immediate attention.
• Photokeratitis:
• Acute pain, redness, and photophobia following UV light exposure.
• Symptoms usually appear 6-12 hours post-exposure.

For management, the following approach can be adopted based on the underlying cause:

• Initial Assessment: Obtain a detailed history, including onset, duration, characteristic of pain, associated symptoms (e.g., discharge, photophobia), and relevant exposures or trauma history.
• Ophthalmic Examination: Include visual acuity assessment, slit-lamp examination, fluorescein staining, and intraocular pressure measurement.
• Management:
• Provide symptomatic relief with pain management and cycloplegics for conditions like anterior uveitis.
• Antimicrobial therapy for infectious causes (bacterial keratitis or conjunctivitis).
• Address underlying systemic conditions for inflammatory causes.
• Immediate ophthalmologic referral for conditions like scleritis, acute glaucoma, and endophthalmitis.

It’s imperative to differentiate between conditions requiring urgent intervention and those amenable to conservative management. If there’s diagnostic uncertainty, a specialist consultation should be pursued.

Eye pain can be a manifestation of a wide range of ocular conditions, each with distinct pathophysiological mechanisms and clinical implications. Understanding the nature, onset, duration, and associated symptoms of eye pain is crucial in forming an accurate differential diagnosis. Here’s a focused assessment of possible causes and their clinical presentations:

1. Superficial Pain:
• Conjunctivitis: Often presents with a gritty or itchy sensation, rather than severe pain. If infected or allergic, it may include watery, mucoid, mucopurulent, or purulent discharge.
• Episcleritis: Typically mild discomfort rather than true pain. It presents with sectoral redness that blanches with vasoconstrictors and may be recurrent.
• Corneal Abrasion: Causes sharp pain, photophobia, and a foreign body sensation. Examination might reveal an epithelial defect.
• Photokeratitis: Causes intense, burning pain, typically following exposure to UV light, with symptoms peaking 6-12 hours post-exposure, including redness and photophobia.
• Deep/Ocular Pain:
• Scleritis: This condition is associated with severe, deep, boring pain. The scleral and episcleral vessels are deeply engorged and do not blanch with vasoconstrictors. Pain can radiate and is often described as worsening at night.
• Keratitis: Especially when infectious or inflammatory, can cause significant pain, along with photophobia, circumlimbal redness, and corneal infiltrates.
• Anterior Uveitis: Typically presents with deep ocular pain, photophobia, redness, and visual disturbances. Slit-lamp examination may reveal keratic precipitates and inflammatory cells in the anterior chamber.
• Acute Angle-Closure Glaucoma: This is an ophthalmologic emergency characterized by severe ocular pain, headache, nausea, and vomiting, along with a red eye, corneal edema, and dramatically elevated intraocular pressure.
• Associated Symptoms to Explore:
• Photophobia and Epiphora (Excessive Tear Production): Often accompany corneal and anterior chamber involvement, such as in keratitis or uveitis.
• Redness: The pattern of redness (diffuse, circumlimbal, sectoral) can aid diagnosis.
• Visual Changes: Complaints of decreased visual acuity may indicate more serious intraocular involvement or complications.

Management and Referral Considerations:

• Immediate Action: Conditions such as acute angle-closure glaucoma and scleritis require urgent ophthalmologic referral due to the risk of vision loss.
• Pain Management: Depending on the cause, analgesics, cycloplegics, or topical NSAIDs might be used for relief.
• Investigations: Visual acuity testing, slit-lamp examination, and measurement of intraocular pressure are essential steps for thorough assessment.
• Observational Insight: A comprehensive patient history considering the timeline of symptom onset, recent trauma or exposure, and systemic associations (e.g., autoimmune conditions) is critical.

For healthcare professionals managing patients with eye pain, it is pivotal to consider both benign and serious causes, to promptly identify and manage conditions that pose a risk to ocular health.