Practical Emergency Ophthalmology Handbook

An Algorithm Based Approach to Ophthalmic Emergencies

Amy-lee Shirodkar, Gwyn Samuel Williams, Amy-lee Shirodkar, Gwyn Samuel Williams

• Publisher: CRC Press
• Year: 2019
• ISBN:
  9780429656521
• Edition: 1
• Topic: Medicine
• Subtopic: Medical Theory, Practice & Reference

This handbook is designed to help shape the thought processes of the eye clinician or trainee and guide them toward the right decision-making pathway in emergency ophthalmology situations. Chapters are titled by the way cases present to eye casualty rather than condition, along with an algorithmic approach on what clinical and laboratory investigations to carry out. There is also guidance on how to perform simple procedures. It is aimed at trainees, general ophthalmologists and those with an interest from allied specialties (including specialist nurses) and professions such as optometrists and emergency medicine doctors.

Key Features

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• Stresses safe and practical navigation of common eye symptoms presented in an emergency setting.

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• Provides guidance on differential diagnosis and includes useful decision-making flowcharts.

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• Emphasizes "how to" approach the eye casualty patient.

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• Shows what can be expected at each stage of the eye injury patient encounter.

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• Presents information appropriate for the entire multi-disciplinary eye casualty team

1 The Red Eye: Basic Algorithm on How to Differentiate Main Conditions from Each Other

Amy-lee Shirodkar

Key Points

1.Appreciate the difference between causes of a red eye that are urgent vs non-urgent

2.Causes of a red eye tend to involve the anterior segment

3.Associated symptoms and history will help localise the problem

4.Lid eversion and checking for corneal sensation are often missed

Diagram of Algorithm

Referral and Presentation

This is the commonest and least useful presentation of any ophthalmic condition. It can range from the trivial to the potentially blinding and even life-threatening. As such patients may present with a red eye for different reasons and at different time periods depending on a thousand factors ranging from a worry at how they look to a deep seated fear of going blind, with factors such as work, booked holidays or childcare arrangements resulting in great variations as to when a patient with the same condition may present to your department. There may be associated pain, tenderness, photophobia or foreign body sensation – depending on the cause. A red eye might be associated with blurred vision or indeed there may be no visual disability whatsoever. There may be no true emergency, but the eye may just look alarming to friends and family, such as classically with a subconjunctival haemorrhage. Either way, a patient has presented to you with a red eye but you should, through triage, see the true emergencies first: penetrating trauma, acute angle closure glaucoma (AACG) or endophthalmitis for example. Triage is fundamental here more than anywhere.

Knowing the patient’s medical history may immediately guide you toward the likely diagnosis, especially if they suffer ocular conditions that have a high risk of recurring such as uveitis, marginal keratitis and herpetic disease for example, or have recently had eye surgery. Systemic conditions with known ocular associations should guide thought processes such that patients with rheumatoid arthritis for example may be more likely to present with corneal melting and scleritis than a patient who has osteoarthritis. Taking a drug history may shine the light on a reason for extensive subconjunctival haemorrhage such as an anticoagulant or use of a topical medication causing allergy. Other important questions to ask in the history include: contact lens wear, potential causes of trauma, recent surgery, previous ocular conditions and past medical history including atopy.

Differential Diagnosis

The eye may appear red for two reasons: haemorrhage or inflammation. Haemorrhage can appear spontaneously such as with subconjunctival haemorrhage after trauma (blunt, penetrating or iatrogenic) or secondary to infections such as viral conjunctivitis. A red, injected eye with varying pain may be due to inflammation or infection of one or more components of the eye. There are two main ways to sort out the causes of a red eye in your mind. One method is to classify causes by anatomy (see Table 1.1) the second by severity and likelihood of permanent visual injury (see Table 1.2). Ultimately there are only a handful of true ophthalmic emergencies that will cause permanent sight loss if not treated urgently: orbital cellulitis, retrobulbar haemorrhage, AACG, globe disruption (through trauma or corneoscleral melting) and endophthalmitis. The other eye conditions can be classified as urgent or non-urgent depending on the probability of causing permanent irreversible blindness.

Table 1.1: Causes of Red Eye Diagnoses Depending on Affected Area
Affected Area	Causes of Red Eye
Eyelids	Cellulitis – orbital, preseptal Blepharitis Molluscum Herpes zoster ophthalmicus Entropion, ectropion, trichiasis
Conjunctiva	SCH Conjunctivitis – infective, allergic, autoimmune
Sclera/episclera	Scleritis, episcleritis
Cornea	Keratitis Infective – viral, bacterial, acanthamoeba Inflammatory – marginal keratitis, peripheral ulcerative keratitis, superior limbic keratitis Corneal abrasion, erosion, exposure Neuropathic causes of abrasion or ulceration
Anterior chamber	Uveitis, hyphema
Raised IOP	Glaucoma – AACG, secondary causes
Lens	Phacolytic, phacomorphic, phacoanaphylactic glaucoma
Others	Carotid cavernous fistula, malignant lesions, retrobulbar haemorrhage
Trauma	Laceration – eyelids, cornea, sclera, IOFB

Table 1.2: Triage of Red Eye Depending on Cause
Emergency	Urgent	Non-Urgent
Acute angle ...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Dedication
• Contents
• Foreword
• Introduction
• Editors
• Contributors
• 1. The Red Eye: Basic Algorithm on How to Differentiate Main Conditions from Each Other
• 2. Cellulitis and Swelling around One or Both Eyelids
• 3. Watery Eyes
• 4. Trauma to the Eyelids and Periorbital Region
• 5. Corneal Ulcers and Contact Lens Keratitis
• 6. Corneal Defects, Abrasions and Foreign Bodies
• 7. Photophobia and Anterior Uveitis
• 8. Red Eyes after Cataract Surgery and Other Operations
• 9. Apparent Sudden Visual Loss: An Essential Approach
• 10. Flashing Lights and Floaters
• 11. New Haemorrhages in the Vitreous and/or Retina
• 12. There is Something Strange and Unusual at the Back of the Eye
• 13. Wavy Lines, Distorted Vision and Blur
• 14. Vitritis and Posterior Uveitis
• 15. The Painful Eyeball
• 16. Retinal Tears and Detachments
• 17. One or More Bulging Eyes
• 18. Double Vision and New Onset Strabismus in an Adult
• 19. My Baby Has a White Pupil in This Photograph and/or Has a Squint
• 20. Non-Accidental Injury
• 21. One or Both Optic Discs are Swollen
• 22. Headaches and Pain in the Temple
• 23. Managing Ocular Trauma
• 24. Called to ITU to Examine a Fundus
• 25. When There Are Symptoms But it All Looks Totally Normal
• 26. Triage
• 27. Summary of Approach
• 28. The Moral Ophthalmologist
• Index