Sunday, June 28, 2009

Case based learning (Ophthalmology)

1 case followed by 2 scenarios.

These slides are a compilation of my short and humble experience in various departments. It is also altered slightly for the purpose of case based learning. However, the identity is not revealed for the privacy of the patient.

Case proper

A 45 year old woman came into HTJS accident and emergency department. For the previous 2 days, her left eye had been red and watering. There was slight blurring of vision and the eye was moderately uncomfortable. There was no history of trauma. There right eye was asymptomatic. There was no past eye history. She was fit and well and not taking any pharmacological or traditional medication.

The acute red eye is a common ophthalmological presentation caused by various conditions ranging from trivial to sight-threatening.

What are the important causes of red eye do you know of?

Answer: (Please click & drag the empty section below to reveal the hidden answer. ^_^)

Are you contented with the history taken?

If yes, justify your statement.

If no, what further questions would you have asked her?

Suggest some physical examination you would carry out in this patient to aid in your diagnosis and their expected findings.

Answer: (Please click & drag the empty section below to reveal the hidden answer. ^_^)

¨ recent upper-respiratory tract infection

¨ direct contact with an infected person

¨ onset (abrupt / insidious)

¨ type of visual blurring (isolated fields/all fields)

¨ photophobia (secondary iritis)

¨ rash (herpes simplex)

¨ headache

¨ Examine the eye with its adnexa. (also with fluorescein stain)

¨ Direct ophthalmoscope

¨ Visual acuity & visual field

¨ Lymph node palpation

With the symptoms she had, what is the most likely diagnosis?

Answer: (Please click & drag the empty section below to reveal the hidden answer. ^_^)

Acute viral conjuctivitis

Dr. Ceccilia of the A&E department diagnosed her to be viral conjunctivitis and commenced a broad spectrum topical antibiotic, arranging a routine review appointment in 3 days but warning the patient to return urgently prior to this if the symptoms worsened.

Do you agree with this method of management?

What would be your management for her?

Answer: (Please click & drag the empty section below to reveal the hidden answer. ^_^)

Management for viral conjunctivitis is supportive and no specific treatment is available.

¨ Topical antiviral agents (e.g. aciclovir, trifluorothymidine) are effective against herpes simplex.

¨ Vasoconstrictors/ antihistamine may reduce symptoms.

¨ Artificial tears are used for soothing effect.

¨ Antibiotics are prescribed only when diagnosis is in doubt.

¨ Topical steroids reduces symptoms but should be used when diagnosis is certain & under ophthalmological supervision.

¨ Antihistamines

¨ Levocabastine HCl 0.05% ophthalmic solution (Livostin)

¨ 1 drop four times daily (up to 2 weeks)

¨ Emedastine difumarate 0.05% solution (Emadine)

¨ 1 drop four times daily

¨ Mast cell stabilizers

¨ Cromolyn sodium 4% solution (Crolom)

¨ 1 drop four to six times daily

¨ Ketotifen fumarate 0.025% solution (Zaditor)

¨ 1 drop two to four times daily

¨ Lodoxamide tromethamine 0.1% solution (Alomide)

¨ 1 or 2 drops four times daily (up to 3 months)

¨ Nedocromil sodium 2% solution (Alocril)

¨ 1 drop twice daily

¨ Olopatadine hydrochloride 0.1% solution (Patanol)

¨ 1 drop twice daily

Sccenario 1

The patient returned to the hospital later the same day complaining that the pan in the left eye had become severe. There was now frontal headache and malaise. The vision in the eye had become much worst (counting fingers only). The eye was very inflamed and the cornea looked hazy. The pupil was oval in shape and failed to react to direct and consensual light stimulation. There was left relative afferent pupillary defect.

What is the most likely diagnosis? What features of the history and examination lead you to this conclusion?

Answer: (Please click & drag the empty section below to reveal the hidden answer. ^_^)

¨ Acute angle closure glaucome

¡ Unilateral eye pain

¡ Often with headache

¡ Poor vision

¡ Hazy cornea (due to oedema)

¡ Oval mid-dilated fixed pupil

¡ Haloes around lights (corneal oedema)

¡ Loss of red reflex

¡ Hypermetropia

¡ Previous symptoms of similar attack

¡ Nausea, vomiting

What is the differential diagnosis and why?

Answer: (Please click & drag the empty section below to reveal the hidden answer. ^_^)

¨ Iritis is the main differential diagnosis, but few other conditions cause such pain with visual loss.

¨ Conjunctivitis and blepharitis cause disconfort only.

¨ Acute corneal problems may cause pain but usually there is a history of trauma or an obvious ulcer on staining with fluorescein.

How would you manage this patient?

Answer: (Please click & drag the empty section below to reveal the hidden answer. ^_^)

¨ Urgent referral to an ophthalmologist is necessary, as permanent visual loss can rapidly occur if untreated.

¨ Initial treatment is to lower the intraocular pressure using

¡ β-blocker :Timolol, 0.5%, 1 drop in the affected eye

¡ Cholinergic :Pilocarpine, 2% eyedrops, two drops every 15 minutes for 2–3 hours

¡ Carbonic A.I. :Acetazolamide, 500 mg orally or 250 mg intravenously

¡ α-adrenergic :Apraclonidine, 1%, one drop every 12h)

¡ Oral agents :glycerol, 1.0 to 1.5 g/kg in a 50% solution

ú oral isosorbide can be substituted (1.5 to 2.0 g/kg).

¡ Intravenous :mannitol (20% solution, 2 g/kg given over 30 min)

¨ Give sedation, antiemetics, and analgesics as necessary to control pain nausea and agitation.

¨ peripheral iridotomy, which establishes a communication between the posterior and anterior chambers & prevent further occurance. (argon or Nd:YAG laser)

¨Rarely, surgical peripheral iridectomy is required.

Scenario 2

The patient attended the next appointment as scheduled, but the left eye was now considerably more uncomfortable and visual acuity was reduced to 6/18. Photophobia was a prominent feature. Dr. Cecilia suspected acute glaucoma. The appearance of the left eye is as below.

Describe the abnormality seen here and suggest the diagnosis.

Answer: (Please click & drag the empty section below to reveal the hidden answer. ^_^)

This is acute uveitis. The episcleral vessels are dilated (ciliary fluch), the corneal appears misty (endothelium is covered with inflammatory precipitates), and the iris is indistinct due to the anterior chamber cellular reaction. There is a mixed hypopyon (layered white blood cells) and hyphema (hemorrhage) within the inferior anterior chamber. The pupil has scarred in places to the lens by posterior synechiae, which causes the irregular appearance of the pupil.

What is the management of this condition?

Answer: (Please click & drag the empty section below to reveal the hidden answer. ^_^)

¨ Topical steroids are the main treatment. A dilating drop such as atropine, cyclopentolate or homatropine can also be prescribed: as this eases the pain and helps stop the formation of permanent posterior synechiae (adhesions between the iris and lens)

What are the systemic associations of this disorder?

Answer: (Please click & drag the empty section below to reveal the hidden answer. ^_^)

¨ ¾ of all cases are idiopathic. Ankylosing spondylitis, Reiter’s syndrome, psoriatic arthritis, arthritis of inflammatory bowel diseases (Crohn’s disease, ulcerative colitis), sarcoidosis, juvenile chronic arthritis are the most frequently identified associations.



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