Pathophysiology
What is the difference between Keratitis, Corneal Abrasion, and Corneal Ulcer
Keratitis describes inflammation of the cornea.
A corneal ulcer describes a defect in the cornea, typically secondary to an infectious cause.
Corneal abrasions refer to any defect of the corneal epithelium and most commonly come about from a recent history of local trauma
Which is typically the most painful?
Corneal Ulcer
What is the Diagnosis?
Normal
For contact lens wearers who present with keratitis, how long should they stop wearing contact lenses for?
Just until symptoms resolve
List two risk factors for a Corneal Ulcer.
100 points each
Which typically presents with only water discharge?
Which typically presents with only purelant discharge?
Corneal Abrasion
Corneal Ulcer
What is the Diagnosis
HSV Keratitis
What is the name of the drug often given for corneal pain and photophobia relief?
Cyclopentolate
What is the name of a specific keratitis that has an environmental cause and is often associated with construction, manufacturing, and engineering industries? - 150
Which job in these industries is at high risk? - 150
Photokeratitis
Welder
List three complications of untreated Keratitis
Complications may include:
What is the Diagnosis
Blunt Trauma
A 32-year-old man presents to the emergency department with acute eye pain, tearing, and light sensitivity after scratching his left eye. He describes a gritty sensation and mild vision blurring but does not report a foreign body sensation. His visual acuity is normal, and there is no discharge.
On examination, the conjunctiva is mildly injected, and the cornea appears clear. Fluorescein staining reveals a small area of corneal uptake, and the rest of the eye examination is unremarkable.
Which option is the best next step?
Prescribe analgesia and monitor
Prescribe oral antibiotics
Prescribe oral corticosteroids
Prescribe topical antibiotic eyedrops
Prescribe topical corticosteroid eyedrops
Prescribe topical antibiotic eyedrops
The symptoms of acute eye pain, tearing, light sensitivity, and the gritty sensation, along with fluorescein staining showing a small area of corneal uptake, indicate a corneal abrasion. Topical antibiotic eyedrops are recommended to prevent secondary bacterial infection of the corneal abrasion. They are effective for managing minor corneal injuries and supporting proper healing. Given that there are no signs of severe infection or inflammation, topical antibiotics are the most appropriate treatment.
List 4 infectious causes of Keratitis - 200
Examples of each - 50 points each
Bacterial - Staph aureus, pseudomonas aeruginonsa
Fungal - Candidiasis
Amoebic - Acanthamoeba
Parasitic - Onchocerca Volvulus
Virus - Herpes
A 38-year-old lifeguard presents to the Emergency Department with intense right-sided eye pain and reports the sensation of a foreign body, despite having removed his contact lenses.
On examination, the right eye has conjunctival injection. His visual acuity is 6/6 in the left eye and 6/12 in the right eye. His ocular reflexes are intact, although he displays photophobia; tearing and discharge are also noted. Inspection under a slit lamp reveals mild, regular ulceration of the right eye.
What is the most likely Organism?
Acanthamoeba keratitis
Acanthamoeba keratitis is correct as this is a cause of contact lens-associated eye disease commonly associated with contact lens use in bodies of water such as the sea or swimming pools. However, soil and ponds can also harbour the amoeba. This patient is a contact lens wearer as indicated in the stem, and his job as a lifeguard means he is likely exposed to bodies of water frequently, putting him at an increased risk of amoeba infection of the eyes. Patients often report eye pain out of proportion to clinical findings, reduced visual acuity, redness, photophobia, and discharge. The treatment is through antiamoebic such as combined biguanide and diamidine therapy.
What colour will a corneal abrasion be once it is stained with fluorescein? -100
What colour light is used to enhance the visualisation of the staining - 100
What metal is used in the filter to create this colour light - 200
Yellow/Green
Blue
Cobalt
A 32-year-old man presents to his GP with a 2-day history of a red and painful right eye which is associated with photophobia. He normally wears contact lenses but he has been using glasses since the pain started.
The patient has a past medical history of allergic rhinitis and takes daily cetirizine.
On examination of the right eye, dilated conjunctival and episcleral vessels are seen. Mild eyelid oedema and increased lacrimation are seen. The left eye is normal. Visual acuity corrected with glasses is 6/6 in the left eye and 6/12 in the right eye.
What is the most appropriate management?
Refer Urgently to Eye Casualty
Contact lens wearers who present with a red, painful eye should be referred to eye casualty to exclude microbial keratitis
A 25-year-old man presents to his GP complaining of a red and painful eye. His right eye has been red and watery since yesterday morning, with a gritty sensation. He usually wears contact lenses on a daily basis. However, has found it too painful to use these since his symptoms began.
On fundoscopy, the GP visualises a hypopyon in the right eye. No foreign body is visible. The left eye appears normal. Both pupils are round, equal and reactive to light. Visual acuity is normal when wearing glasses, however marked photophobia is evident in the right eye.
What organism is the most likely cause of these symptoms?
Pseudomonas aeruginosa
The symptoms and presentation here are indicative of keratitis. The most common cause of bacterial keratitis in contact lens wearers is Pseudomonas aeruginosa.
You are an FY-2 doctor in ophthalmology. A 58-year-old male presents with a painful right eye. He also has some tearing of the eye and a reduced vision. On examination you identify a corneal ulcer.
What type of eye drop is most likely to have caused the ulcer?
Steroid Eye Drops
Steroid eye drops are a risk factor, this is because they act by reducing inflammation and thus the immune reaction to an infection, this leads the cornea at risk of infection from a bacteria, fungi or protists.
A 28-year-old man presents to the emergency department after getting a metal fragment in his eye while grinding steel. He complains of severe pain, tearing, and photophobia. On examination, his visual acuity is 6/9 in the affected eye. The conjunctiva is injected, and there is mild anterior chamber flare.
What is the most appropriate next step in the assessment of this patient’s eye?
Fluorescein staining of the cornea
Fluorescein staining should be used when suspecting any corneal damage to see the extent of damage and ?penetrating injury
A 36-year-old female teacher presents to emergency eye casualty with unilateral right-sided red eye which is acutely painful. She complains of burning pain around the eye, photophobia and you note her eye is tearing excessively. Fluorescein staining shows a linear, branching epithelial defect. She is not a contact lens wearer and she has no past medical history of note.
Which option below is the most appropriate management?
Topical Aciclovir
This patient is presenting with symptoms of herpes simplex keratitis - painful red eye with photophobia and epiphora. This diagnosis is further supported by abnormal fluorescein staining, typical appearance is a linear branching corneal ulcer. The management for this condition is topical aciclovir.