The Optometrist's Guide to Red Eye

It’s Friday night, and the clinic is closing in less than an hour when you receive an emergency call. The patient complains of a red eye. How many optometrists can relate to this scenario?

Red eye is one of the most common ocular concerns that arise on a weekly basis in the offices of optometrists and physicians. Most patients continue to visit their physicians for these concerns. An Australian study found that 64% of treated cases by primary care physicians were misdiagnosed and 10% led to serious complications.⁶ Misdiagnosis and not knowing when to refer the patients can result in devastating consequences. Before going over a few common conditions, let’s go back to the basics.

Back to the basics

One of the basic aspects as physicians is communication. Taking an in-depth case history and determining the patient’s chief complaint is beneficial to streamline the eye examination. The chief complaint of red eyes may yield an extensive list of differentials and a detailed case history can formulate differential diagnoses. Listed below are a few important questions.

Case history for red eye


Frequency	Previous episode or history?
Onset	Acute vs Chronic?
Location	Unilateral or Bilateral? Diffuse or Localized?
Duration	How long have symptoms been present?
Alleviating factors	Use of artificial tears or other eye drops? Cold compresses?
Related symptoms	Discharge? Burning? Tearing? Itching? Pain? Photophobia? Foreign body sensation? Blurry vision?
Quality	Pain threshold? (on scale of 1 to 10)
Ocular history	History of trauma or chemical injury? Exposure to an infected person? Contact lens wearer? Use of topical or over the counter drops?
Medical/Social history	Recent illness or infections? Computer use? Occupation? Smoking history?

Communication, observations and listening to key phrases can narrow down a list of differential diagnoses. For example: a patient says ‘My eyes are always itchy’ which may indicate allergies or if your patient walks into the exam room wearing sunglasses, the patient may be photophobic. Good communication skills and bedside manner are critical skills for all physicians and can help lead to a more accurate diagnosis for the patient.

This article is a review of a few conditions commonly associated with red eyes, listed in order of urgency of the conditions (least to most urgent).

Subconjunctival hemorrhage
Dry eye syndrome
Conjunctivitis
Contact lens related problems
Episcleritis/Scleritis
Iritis
Foreign body & Corneal abrasion

Subconjunctival hemorrhage

Subconjunctival hemorrhage is defined as diffuse or focal area of blood under the conjunctiva due to ruptured conjunctival blood vessel. Patients are usually asymptomatic.

Figure 1: Subconjunctival hemorrhage²


Key phrase	“I did not notice anything until someone said something.”
Etiology	Idiopathic Valsalva (coughing, sneezing, constipation) Trauma (isolated or associated with retrobulbar hemorrhage or ruptured globe) Systemic conditions (hypertension, diabetes) Bleeding disorders Use of antiplatelet or anticoagulant medications (aspirin, clopidogrel, warfarin)
Signs	Focal or diffused hemorrhage Rule out conjunctival lesions and ruptured globe (check extraocular motility, intraocular pressure) If recurrent or suspect bleeding disorder, refer for blood work (bleeding time, prothrombin time, partial thromboplastin time, complete blood count, liver function test, protein C and protein S)
Treatment	Condition is self-limiting with spontaneous resolution within 2-3 weeks Artificial tears may be given if ocular irritation is present
Follow up	No follow up necessary unless condition reoccurs Refer to family doctor for high blood pressure and bleeding disorder if recurrent

Dry eye syndrome

Keratoconjunctivitis sicca, also known as dry eye syndrome, is caused by decreased tear production or poor tear quality. It may be associated with increased age, female > male, medications and some medical conditions.


Key phrase	“My eyes are watering and I feel like something is in it.”
Symptoms	Burning/Dryness Foreign body sensation Excessive tearing
Signs	Scant, irregular tear prism at inferior eyelid margin Decreased tear break-up time Punctate corneal or conjunctival staining Excess mucus or debris in tear film Meibomian gland dysfunction
Treatment	Artificial tears Lubricating ointment QHS or lubricating gel QHS Lifestyle modifications (use of humidifiers, smoking cessation) Cyclosporine 0.05% BID for chronic dry eye
Follow up	Depends on severity

Conjunctivitis

Conjunctivitis is the most common cause of red eyes, viral being the most prevalent. The term conjunctivitis refers to the inflammation of the conjunctiva. Below are a few clinical pearls for differentiating viral, bacterial and allergic conjunctivitis.

Viral Conjunctivitis

Figure 2: Viral conjunctivitis²


Key phrase	“I think I have pink eye.”
Prevalence	Most prevalent (80%)
Contagious	Highly for 10-12 days
Medical history	Recent upper respiratory tract infection(cough/flu)
Location	Unilateral or bilateral
Symptoms	Itching/Burning Foreign body sensation Tearing
Discharge	Watery
Preauricular nodes	Tender nodes
Other signs	Follicles inferiorly Edematous eyelids Intraepithelial microcyst Subepithelial infiltrates
Treatment	Self-limiting; however, palliative therapies include: Artificial tears Mild steroid (if necessary)
Counseling	Copious handwashing Avoid touching eyes
Follow up	2 weeks or sooner if condition worsens

Bacterial Conjunctivitis

Figure 3: Bacterial conjunctivitis³


Key phrase	“My lids are shut closed when I wake up.” “My eyes are goopy.”
Prevalence	Second most prevalent Children > Adults
Contagious	Yes
Medical history	None
Location	Unilateral or bilateral
Symptoms	Foreign body sensation Matted eyelashes
Discharge	White/yellow purulent
Preauricular nodes	No
Other signs	Conjunctival papillae Moderate hyperemia Conjunctival chemosis
Treatment	Broad spectrum antibiotic (5-7 day course)
Counseling	Avoid touching eyes
Follow up	2-3 days then every 5-7 days until resolved

Allergic conjunctivitis

Figure 4: Allergic conjunctivitis²


Key phrase	“My eyes are itchy."
Prevalence	During allergy season
Contagious	No
Medical history	Seasonal allergies Airborne allergens
Location	Usually bilateral
Symptoms	Itching & burning
Discharge	Watery
Preauricular nodes	No
Other signs	Conjunctival papillae Mild hyperemia Conjunctival chemosis Red edematous eyelids
Treatment	Cold compresses Artificial tears Anti-histamine or Mast cell inhibitors Mild steroid (if necessary) Oral anti-histamine (if necessary)
Counseling	Eliminate allergen Avoid rubbing eyes
Follow up	1-2 weeks

Contact lens related problems

Contact lenses are used for correcting refractive errors, for cosmetic use and for therapeutic use such as bandage lens. However, contact lens overwear may cause several complications including giant papillary conjunctivitis, superior limbic keratoconjunctivitis & corneal ulcer.

Giant Papillary Conjunctivitis

Figure 5: Giant papillary conjunctivitis³


Key phrase	“My eyelids feel heavy and I need to rub them.”
Etiology	Contact lens overwear Loose fit (excessive lens movement)
Symptoms	Itching & burning Foreign body sensation
Signs	Upper tarsal micropapillae Superior limbal injection Ropy mucous discharge
Treatment	Educate patient on proper contact lens care For mild GPC: Decrease wear time of contact lenses Topical mast cell inhibitor or antihistamine For severe GPC: Suspend use of contact lenses Topical steroid
Follow up	2-4 weeks

Superior Limbic Keratoconjunctivitis

Figure 6: Superior limbic keratoconjunctivitis²


Key phrase	“I cannot wear my contacts for long anymore.” “I have to take out my contact lenses more often.”
Etiology	Hypersensitivity/toxicity reaction to preservatives in contact lens solution
Symptoms	Itching & burning Foreign body sensation Contact lens intolerance
Signs	Upper tarsal micropapillae Superior limbal injection Pannus at 12 o’clock
Treatment	Suspend use of contact lenses Switch to preservative free contact lens solution Use preservative free artificial tears Topical steroid (if necessary)
Follow up	2-4 weeks

Corneal Infiltrate & Corneal Ulcer

Figure 7: Corneal ulcer³


Key phrase	"My eyes are red and hurt.”
Etiology	Bacterial Fungal Acanthamoeba
Symptoms	Pain Photophobia Contact lens intolerance
Signs	White stromal opacity Corneal thinning/ulcer Anterior chamber reaction
Treatment	Cycloplegic drops for comfort For mild condition: Fluoroquinolone q1-2 hrs For severe condition: Fluoroquinolone q1-2 hrs
Follow up	1 day Maintain treatment until condition resolves

Episcleritis & Scleritis

Episcleritis is a localized area of inflammation of connective tissue between sclera and conjunctiva involving whereas scleritis is defined as an inflammation of the scleral tissue.

Episcleritis

Figure 8: Episcleritis³


Key phrase	“My eye is red in the corner.”
Epidemiology	80% simple, 20% nodular Bilateral in 33% of cases
Etiology	Idiopathic Infectious (herpes zoster) Other (rosacea, atopy, collagen vascular disease, gout, thyroid disease)
Symptoms	Mild pain Hyperemia
Signs	Sectoral injection Chemosis Episcleral nodules Cells and flare
Treatment	Artificial tears Topical steroid (Fluorometholone QID) Oral NSAID for severe cases
Follow up	1 week
Prognosis	Self-limiting condition & good prognosis Recurrent in 67% of cases

Scleritis

Figure 9: Scleritis³


Key phrase	“My eye is red and it hurts.”
Epidemiology	40% diffuse, 44% nodular, 14% necrotizing
Etiology	Idiopathic Connective tissue disease Herpes zoster ophthalmicus Syphilis
Symptoms	Severe pain Hyperemia & chemosis
Signs	Decreased vision Diffused injection Chemosis Scleral nodules Globe tenderness Cells and flare
Treatment	Oral steroid (Prednisone 60-100 mg po QD) Systemic NSAID
Follow up	1 week or sooner if symptoms worsen
Prognosis	Depends on etiology (poor for necrotizing) Recurrence is common

Iritis

Iritis, also known as anterior uveitis, is an idiopathic inflammation of uvea (iris, choroid and/or ciliary body).

Figure 10: Keratic precipitates³


Key phrase	“I am light sensitive.”
Symptoms	Pain Redness Photophobia Decreased vision
Signs	Anterior chamber reaction (cells and flare) Ciliary flush Keratic precipitates Hypopyon Iris synechiae
Treatment	Cycloplegic bid Topical steroid (Prednisolone acetate 1% q4-6 hrs depending on severity) May consider steroid ointment overnight
Follow up	Every 1-7 days depending on severity, assess patient’s IOP at each visit Taper steroid once anterior chamber reaction has resolved

Foreign body & corneal abrasion

Defined as defects to the corneal epithelium, corneal abrasion can cause irritation, pain, tearing and photophobia.

Figure 11: Corneal abrasion³


Key phrase	“Something got into my eye and it hurts.”
Risk factors	Foreign body Trauma Contact lens use
Symptoms	Sharp pain Photophobia Foreign body sensation Tearing
Signs	Epithelial defect (stains with fluorescein) Conjunctival injection Mild anterior chamber reaction Protective ptosis
Treatment	For non-contact lens wearer: antibiotic ointment q2-4 hrs or antibiotic drops QID For contact lens wearer: anti-pseudomonas coverage, antibiotic ointment or drop QID For abrasion secondary to fingernail or vegetative matter: Fluoroquinolone QID For large abrasion: place bandage contact lens
Follow up	For bandage contact lens: follow up within 24 hrs for re-evaluation Central or large abrasion: follow up within 24 hrs for re-evaluation Peripheral or small abrasion: follow up within 2-5 days

Conclusion

Red eye is the most common complaint found amongst patients and the concept that every case is a ‘pink eye’ is a huge misunderstanding. The average person will call their family physician if they have an eye problem. There is a misconception that optometrists only provide a spectacle prescription. Upon questioning patients, they are often unaware that optometrists may provide more detailed care including urgent eye problems. Reaching out to family physicians and providing reports for mutual patients can build a foundation for better communication between optometrists and family physicians. Educating patients and the public with regards to our role as primary care optometrists may help to prevent misdiagnosis and further patient consequences. Stay tuned for more details regarding atypical conditions in association with red eyes.

Citations

Cronau H, Kankanala R, Mauger T. Diagnosis and Management of Red Eye in Primary Care. American Family Physician. 2010;81(2):137-144.
Ehlers JP, Shah CP, Fenton GL. Wills Eye Manual Office and Emergency Room Diagnosis and Treatment of Eye Disease. Philadelphia, PA: Wolters Kluwer Health; 2012.
Friedman NJ, Kaiser PK. The Massachusetts Eye and Ear Infirmary: Illustrated Manual of Ophthalmology. Philadelphia, PA: Saunders, Elsevier; 2014.
Frings A, Geerling G, Schargus M. Red Eye: A Guide for Non-specialists. Deutsches Arzteblatt International. 2017;114:302-312. doi:10.3238
Gilani C, Yang A, Yonkers M, Boysen-Osborn M. Differentiating Urgent and Emergent Causes of Acute Red Eye for the Emergency Physician. Western Journal of Emergency Medicine. 2017;18(3):509-517. doi:10.5811
Statham MO, Sharma A, Pane AR. Misdiagnosis of acute eye diseases by primary health care providers: incidence and implications. Med J Aust. 2008;189:402–404
Vo A, Williamson J. Red Eye Roundup. Review of Optometry. https://www.reviewofoptometry.com/article/red-eye-roundup. Published March 15, 2019. C