Unit 460 July 2010

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1. Communication skills and the patient-doctor relationship

2. applied professional knowledge and skills

3. population health and the context of general practice

4. professional and ethical role

5. Organisational and legal dimensions

the five domains of general practice

Subscriptions Call the Subscription Coordinator for all enquiries on 03 8699 0495 or email check@racgp.org.au.Published bythe Royal australian College of general practitioners College House, 1 palmerston Crescent South melbourne, Victoria 3205, australia telephone 03 8699 0414 Facsimile 03 8699 0400 www.racgp.org.auaCN 000 223 807 aBN 34 000 223 807 ISSN 0812-9630© the Royal australian College of general practitioners 2010. all rights reserved.the opinions expressed in check are not necessarily those of the RaCgp.please address all letters concerning the content to the medical editor. Printed by printgraphics pty ltd, 14 Hardner Road, mount Waverley, Victoria 3149 telephone 03 9562 9600.

July 2010 Unit 460

OpHtHalmOlOgy

Editor in Chief Jenni Parsons

medical Editor Kath O’Connor

Editor Nicole Kouros

program Coordinator Morgan Liotta

graphic Designer Jason Farrugia

Illustrator Christopher Nielsen

authors Geoff Spurling Lionel Kowal Carmel Crock Sukhpal Singh Sandhu Chathri Amaratunge Mervyn D Ferdinands Sarah Louise Smithson

Reviewer Trevor Hodson

From the editor 2

Case 1 Judy’s eyelid lump 3

Case 2 Norman’s sudden transient loss of vision 6

Case 3 Ken has a chemical eye injury 10

Case 4 Frank comes for his diabetes check up 14

Case 5 Michael has a unilateral red eye 17

Case 6 Felicity presents with bilateral red eyes 21

Case 7 Jack has a squint 24

References 28

Resources 29

Qa&CpD program requirements 30

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From the editor

this unit of check looks at ophthalmology with clinical scenarios relating to eyelid lumps, transient loss of vision, chemical eye injury, diabetic retinopathy, unilateral red eye, bilateral red eyes and squint in children. Eye problems present commonly in the general practice setting. History and examination should aim to determine the diagnosis, exclude serious differential diagnoses, identify indications for ophthalmology referral and to aid with the development of an evidence based investigation and management plan. all patients should have their visual acuity tested and recorded.

this unit was coordinated by lina Nido mBBS, BmedSci, FRaCgp, gp liaison Officer, Royal Victorian Eye and Ear Hospital (RVEEH). the authors of this unit are:

Dr geoff Spurling mBBS, mpH, FRaCgp, general practitioner at the Inala Indigenous Health Service, southwest Brisbane, and Senior lecturer, School of medicine, University of Queensland

Dr lionel Kowal mBBS, FRaNZCO, FRaCS, Director, Ocular motility Clinic at the RVEEH, and Senior Fellow, Department of Ophthalmology, University of melbourne, and Vice president, International Strabismological association

Dr Carmel Crock mBBS, FaCEm, Blitt, Director, Emergency Department, RVEEH

Dr Sukhpal Singh Sandhu mBChB, FRCOphth, mD, medical Retina Fellow, RVEEH and Centre for Eye Research australia

Dr Chathri amaratunge mBBS(Hons), gDipmed, Ophthalmology Registrar, RVEEH

Dr mervyn D Ferdinands mBBS(Hons), Ophthalmology Registrar, RVEEH

Dr Sarah louise Smithson mBBS, Hospital medical Officer, Royal melbourne Hospital.

the learning objectives of this unit are to:

• recognise the clinical features of chalazia, blepharitis, allergic conjunctivitis and herpes simplex virus keratitis and manage these conditions appropriately

• appreciate that amaurosis fugax is a symptom of carotid artery disease with an associated increased risk of subsequent stroke

• more confidently manage chemical eye injuries with immediate copious eye irrigation and removal of particulate matter followed by slit lamp examination and ophthalmologic opinion

• recognise the importance of screening for diabetic retinopathy to prevent severe vision loss and blindness

• list the differential diagnoses of unilateral and bilateral red eyes and the indicators of sight threatening disease in this setting

• more confidently assess and manage infants who present with squint.

We hope that this unit will assist you to confidently assess and manage patients who present with eye problems in the general practice setting.

Best wishes

Kath O’Connor

Medical Editor

Case 1

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Judy’s eyelid lump

Judy, 60 years of age, complains of a lump in her left upper eyelid, which has gradually increased to a pea size over the last 6 months. She says she has had itchy eyes all her life and her eyes often look like she is wearing pink eyeliner and has dandruff in her eyelashes. She recalls having styes as a child, but none recently.

On examination, Judy has a firm, nontender, pea sized lump on the left upper eyelid. the surface of the lump is smooth and the overlying skin is mobile and there is a pink appearance due to some reactive inflammation (Figure 1).

Question 1

What serious differential diagnoses should be kept in mind?

Question 2 What is the most likely diagnosis?

Question 3 What is the usual prognosis of this condition?

Question 4 What are the risk factors/causes for this condition?

Further history When slight pressure is applied to the lump, a tiny amount of oily discharge is noted at the lid margin. On examination of Judy’s lid margins it is noted that she has a number of tiny raised yellowish lumps (Figure 2).

Figure 1. Judy’s eyelid lump

Figure 2. Judy’s lid margin

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Case 1

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Question 5 What treatment would you suggest for Judy’s eyelid lump and her other eyelid symptoms?

Question 6 What are the indications for surgical intervention? How is this surgery performed?

Answer 1

Sebaceous gland carcinoma should be suspected in older patients (middle aged to elderly) who present with an eyelid lump, particularly if it is recurrent and in the upper eyelid (however, it may present in the lower lid or even both eyelids). Close inspection may reveal loss of eyelashes and meibomian gland orifices in the area. a basal cell carcinoma (BCC) is also a possibility with an eyelid lump but the history of mobile overlying skin makes this unlikely in Judy’s case.

Answer 2

the most likely diagnosis is a chalazion (meibomian cyst or tarsal cyst). Chalazia occur in the tarsal glands, which are located in the tarsal plate, deep to the lash follicles (Figure 3). most commonly, a chalazion develops from an obstructed meibomian gland leading to a chronic, low grade granulomatous inflammation and collection of oily secretions and presenting as a firm, nontender slowly growing lump. In some cases chalazia can occur in the setting of an acute infection of the meibomian gland (internal hordeolum). this is in contrast to a stye (external hordeolum) which is an infection of the small sebaceous glands at the base of the eyelashes.

Answer 3

these lesions may resolve spontaneously over weeks to months. However, in some cases, they do not resolve and require intervention. they may grow large enough to obstruct vision and can also become secondarily infected (internal hordeolum) leading to preseptal cellulitis.

Orbicularis muscle

Orbital septum

Levator palpebrae

Palpebral conjunctiva

Tarsal plate withMeibomian glands

Figure 3. Eyelid anatomy

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Case 1

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Feedback

If Judy develops a meibomian abscess (internal hordeolum), particularly if it is associated with signs of preorbital cellulitis, systemic antibiotic therapy with antibiotics directed at Staphlococcus aureus (ie. dicloxacillin or flucloxacillin) is indicated, in addition to hot compresses. In children under 5 years of age with preorbital cellulitis, particularly in the absence of a stye or meibomian abscess, Streptococcus pneumoniae or Haemophilis influenzae may be implicated. In this case a broad spectrum antibiotic such as amoxycillin and clavulanate should be used. Refer to Therapeutic Guidelines: antibiotic for prescribing information (see Resources).

Answer 6

Surgery is indicated if a chalazion does not improve after a few weeks of conservative therapy. this is usually performed by an ophthalmologist, but can be performed in the general practice setting if the general practitioner attains the necessary skills. Incision and curettage is generally performed under local anaesthetic through the conjunctival surface of the lid. In recurrent cases and/or if another diagnosis is considered (such as a BCC or sebaceous gland carcinoma), the lesion may be sent for pathology. this is not necessary in uncomplicated cases. Chalazia may be of more urgent concern in children if obstructing vision, or inducing astigmatism by pressure on the cornea.

Answer 4

the principal risk factor for chalazion formation is pre-existing blepharitis, mainly posterior blepharitis. Blepharitis is a chronic low grade infection around the eyelid and is divided anatomically into anterior and posterior variants. the two variants often co-exist. anterior blepharitis occurs around the eyelashes and follicles (causing the ‘pink eyeliner’ and ‘dandruff’ appearance described by Judy). posterior blepharitis involves meibomian gland dysfunction with inspissated meibomian secretions. Dysfunction of these oil secreting glands may result in inflammation and thickening of the eyelids, eyelid crusting, and, in the case of gland blockage, chalazion formation. patients may describe a foreign body sensation and/or ‘dry eye’ symptoms. Other risk factors for chalazion formation include seborrhoeic dermatitis of the scalp and acne rosacea.1,2

Answer 5

Judy has symptoms of a chalazion and blepharitis. the following outlines treatment for these conditions.1,2

Chalazion

the initial treatment for a chalazion aims to assist the obstructed meibomian gland to drain via the normal duct. this involves:

• warm compresses (facewasher with warm water) applied for 5–10 minutes 2–4 times per day, followed by light massage to the nodule. this assists to melt the oils within the gland, and massage them out

• a topical antibiotic (chlorsig drops or ointment) to treat any mild infection in the gland openings which may be contributing to the obstruction.

Blepharitis (anterior and posterior)

• lid hygiene – the lids and eyelashes should be cleaned with baby shampoo on a cotton bud 2 times per day to decrease bacterial load in the area

• topical antibiotic – chloramphenical drops or ointment

• In refractory cases, particularly if rosacea is implicated, an oral antibiotic can be considered, eg. doxycycline 100 mg twice per day for 4 weeks

• Ocular lubricants may help with the dry eyes of posterior blepharitis.

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Case 2

Norman’s sudden transient loss of visionNorman, 66 years of age, presents complaining of a brief episode of loss of vision in his left eye. He says his vision went funny while reading the paper, ‘like someone lowered a curtain over my eye’, after which he could not see out of the left eye at all. His vision returned to normal after a few minutes. He noticed no change to the vision in his right eye. He felt otherwise well during the event and reported no associated features. He has no past history of visual disturbance and says he usually has good distance vision but uses a pair of over-the-counter glasses for reading. He has a history of hypertension, hypercholesterolaemia, diverticular disease and alcohol abuse. He quit smoking after 30 years about 3 years ago when he was diagnosed with hypertension and a close friend died of a heart attack. He has no personal or family history of cerebrovascular or cardiovascular disease. He takes irbesartan/hydrochlorothiazide 150 mg/12.5 mg per day, simvastatin 20 mg per day, aspirin 100 mg per day, quinine sulphate 300 mg per day (at night) and an antacid if required.

On examination, visual acuity is 6/6 in both eyes and his pupils are equal and reactive with no relative afferent pupil defect. there is no nystagmus, eye movements are normal, and there is no field defect to confrontation. Fundal examination is normal, in particular there is no evidence of retinal infarction and no cholesterol emboli seen in the retinal vessels. Cranial nerve and upper and lower limb neurological examination is normal. His pulse is regular at 80 bpm, blood pressure (Bp) 150/90, heart sounds normal and there is an audible bruit in the left carotid.

Question 1 What is your assessment of Norman?

Question 2 What investigations, if any, would you order at this stage?

Question 3 What is the risk of subsequent stroke in Norman?

Question 4 How will you stratify Norman’s subsequent stroke risk following his transient ischaemic attack (tIa)?

Further information

Doppler ultrasound imaging of Norman’s internal carotid arteries (ICa) and external carotid arteries (ECa) revealed a very narrow patent channel with trickle flow only in the left ICa and a nonsignificant (

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Case 2

Question 5 How will you manage Norman?

Question 6 What is the impact of stroke on the australian community?

Question 7 What management options should be considered for stroke prevention post-tIa?

Figure 4. Norman’s carotid ultrasound report: near total left ICA stenosis and a nonsignificant (

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Answer 1

amaurosis fugax is the most likely diagnosis in view of the classic sounding history and Norman’s past medical history of hypertension, hypercholesterolaemia and 30 years of smoking (increased vascular risk). amaurosis fugax, also known as ‘transient monocular blindness’ is a painless, monocular loss of vision, and is a form of tIa.3 Vision loss typically occurs in the absence of other neurological features, lasts seconds to minutes and resolves completely. It is caused by transient hypoperfusion of the retina, most commonly as a result of thromboembolic disease. less common causes include vasospasm (including from use of exogenous agents such as cocaine) and haematological causes such as polycythaemia, sickle cell disease, anaemia, and hypercoagulable states.3 amaurosis fugax may also be caused by temporal arteritis (this may occur without the classical headache and jaw claudication). In the thromboembolic form, thrombus development occurs via cholesterol deposition and atheroma formation within arterial lumens of the major vessels proximal to the ophthalmic artery. the thrombus may itself cause transient blood flow cessation but more commonly the thrombus ulcerates and releases emboli, which lodge within vessels and result in distal ischaemia.4

Answer 2

It is important to exclude temporal arteritis with an urgent erythrocyte sedimentation rate (ESR) and/or C-reactive protein (CRp). In addition, the following tests should be ordered:

• a full blood examination to exclude polycythaemia, sickle cell disease and anaemia

• an electrocardiogram to exclude or confirm an arrhythmia

• electrolytes, renal function, fasting lipids, and random glucose to assess risk factors for cardiovascular disease

• doppler ultrasound imaging of the carotids (as the presenting symptoms are in this territory).

Answer 3

Norman has significant risk factors for cardiovascular disease, a carotid bruit, and symptoms of transient monocular blindness so he has a high chance of having thrombotic disease in his ipsilateral carotid artery.4 the ophthalmic artery is the first major branch of the internal carotid artery, and can be involved as one of the first signs of disease.5 there is a significant risk of further thromboembolic events involving any of the other branches of the internal carotid, which supply the cerebral cortex. the estimated risk of ipsilateral stroke,

at 2 years after an amaurosis fugax event is 16.6%.6 amaurosis fugax is therefore a symptom of carotid artery disease and could be the first warning sign of a future stroke.

Answer 4

New guidelines on stratification of stroke risk post-tIa were published in June 2008 by the Royal australian College of general practitioners.7 these guidelines suggest the use of a score known as the ‘aBCD2 score’ to stratify individual risk of stroke after tIa. the aBCD2 score was developed following an Oxford based study and can be used to predict which patients are at high risk of stroke within 7 days of having a tIa. Five potential predictive variables (risk factors) were tested: age, blood pressure, clinical features (motor weakness and speech disturbance), duration of symptoms, and the presence of diabetes – aBCD2 (Table 1).8,9 people with a suspected tIa are at a high risk of subsequent stroke if they have an aBCD2 score of 4 or above, and they should receive immediate initiation of aspirin, specialist assessment within 24 hours of onset of symptoms, and commencement of secondary prevention as soon as the diagnosis is confirmed.7 people with a suspected tIa who have an aBCD2 score of less than 4 are at a lower risk of subsequent stroke but should receive immediate initiation of aspirin, specialist assessment within 72 hours of onset of symptoms, and commencement of secondary prevention as soon as the diagnosis is confirmed.7 Norman has an aBCD2 score of 2 (age >60, elevated blood pressure, ‘other’ symptoms, duration of symptoms 140 mmHg or diastolic ≥90 mmHg)

•1point

Clinical features •2pointsforunilateralweakness

•1pointforspeechdisturbancewithout weakness

•0pointsforother

Duration of symptoms in minutes •2pointsfor≥60mins•1pointfor10to59mins

Presence of diabetes •1point

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stroke, while no significant reduction was noted in patients with stenosis of

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Case 3

Ken has a chemical eye injuryKen, a male labourer, 17 years of age, is brought in to your rooms by his friend. He was working at a building site around the corner from your practice when he accidentally dropped a brick into a bag of cement. the cement powder blew up into both eyes. He has severe pain and cannot open his eyes.

Question 1 What is your immediate management?

Question 2 Describe how you evert an eyelid.

Question 3 What further information would you like to know from Ken?

Question 4 How will you examine him?

Question 5 How do alkali and acid eye injuries differ?

Question 6 How are chemical eye injuries graded?

Question 7 What are the long term complications of chemical eye injuries?

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Case 3

Answer 1

Immediate copious irrigation of the eyes is required. gentle but firm insistence may be needed to irrigate the eyes effectively. topical anaesthetic such as benoxinate will reduce pain and help the patient to be more cooperative; it may be necessary to repeat the medication after 10–15 minutes. Commence with tap water irrigation followed by Hartmann or normal saline solution via intravenous (IV) tubing, for 15–30 minutes or until the pH is normalised1,2 (Figure 5). the end of the IV tubing may be cut to deliver the solution more rapidly to the ocular surface (Figure 6). after irrigation, it is important to take a detailed history, test and record vision and examine the eye more closely. all chemical eye injuries should be referred to an emergency department or ophthalmologist for slit lamp examination of the eye. Details of the equipment and procedure required for eye irrigation are presented below.

Equipment

Cotton buds, benoxinate eye drops, IV tubing, 1 l bag of Hartmann or normal saline solution, litmus paper.

Procedure

In order to ensure the entire ocular surface is thoroughly irrigated, systematically ask the patient to look in all directions of gaze as irrigation is performed. the upper and lower lids should be everted and irrigated. Sweep the upper and lower fornices with a moistened cotton tipped applicator (Figure 7). Remove any particulate matter from the ocular surface and fornices. Remove necrotic (loose) conjunctival tissue as it may contain chemicals that could continue to leach into the eye. at 5–10 minutes after irrigation, the tear film pH may be checked using litmus paper placed on the inferior fornix (Figure 8). Irrigation should continue for 15–30 minutes or until the pH is neutral/near neutral (pH 7).

Answer 2

this is an essential skill for the gp and requires practice.

Instruct the patient to look downwards. grasp the upper lid lashes at the lid margin between thumb and forefinger and pull the lid away from the eye. place the tip of a cotton bud 1 cm superior to the lid margin. Evert the eyelid over the cotton bud (Figure 9). gentle pressure by the thumb or index finger on the lid margin will hold the everted lid in place and the cotton bud

Figure 7. Sweeping the upper lid with a cotton tipped applicator

Figure 6. Rapid irrigation with the end of the IV tubing cut off

Figure 5. Eye irrigation with saline

Figure 8. Litmus paper

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Case 3

Answer 4

the key features on examination include:

• visual acuity (this should be tested and recorded)

• assessment of the conjunctiva and cornea (look for conjunctival hyperaemia, chemosis [conjunctival swelling] and corneal clouding. the eye should be stained with fluorescein. a corneal/conjunctival epithelial defect stains green with fluorescein when a cobalt blue light is used. Beware that when there is complete sloughing of the entire corneal epithelium the uptake of fluorescein may be poor, and this may be mistakenly interpreted as no uptake of fluorescein)

• looking for limbal ischaemia (the cornea is avascular and relies on diffusion from the limbus. Damage to the limbal vessels will compromise the ability of the cornea to re-epithelialise. there may be blanching of conjunctival or episcleral vessels)

• checking for associated injury (examine for burns or other injury to periocular skin. In blast or thermal injuries there may be damage to upper airways, penetrating injury or an intraocular foreign body).

Answer 5

acid or alkali injury to the eye may occur from domestic and industrial products – household cleaning products and cosmetics are commonly implicated. alkali injury to the eye is more common and, as a general rule, is more severe. an alkali causes liquefactive necrosis of the surface epithelium of the eye, which allows for rapid penetration to the deeper layers (Figure 11). an acid injury causes coagulative necrosis of the cornea, which limits the ability of the acid to penetrate the eye (Figure 12). Explosion of a car battery can cause a chemical injury from sulphuric acid in addition to thermal injury, high velocity injury, and foreign body penetration of the eye. Hydrofluoric acid causes the most serious ocular acid injury, resulting in liquefactive necrosis similar to an alkali injury.15 Table 2 and 3 show common products containing acid and alkali.

may be removed (Figure 10). Irrigation and sweeping of the upper fornix with a moistened cotton bud may be performed. Instructing the patient to look up at the end of the procedure will return the lid to its normal position.

Answer 3

the key features of the history include:13

• type of chemical (many workers will come with an information sheet on the substance, however, it may be necessary to consult poisons information)14

• duration of exposure

• first aid measures taken (Was the eye irrigated? For how long and with what fluid?)

• protective eyewear (Were goggles or safety glasses being worn?)

• associated injuries (Was there an explosion or a thermal injury?)

• tetanus status.

Figure 10. Everting the lid: step 2

Figure 9. Everting the lid: step 1

Figure 11. Severe alkali injury to the eye

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Case 3

damage in less than 1 minute, lye causes deep ocular injury in 1–3 minutes)15

• whether there is retention of particulate matter

• whether there is associated thermal burn (eg. magnesium hydroxide in fireworks is an alkali which causes a coexistent thermal burn).

Answer 7

Conjunctival burns may cause symblepharon formation and keratoconjunctivitis sicca and entropion (Figure 13). loss of limbal stem cells may lead to conjunctivalisation and vascularisation of cornea as well as corneal opacification. Corneal perforation may occur. When the chemical penetrates the anterior chamber, iris and lens damage may occur.

Feedback

Chemical injuries are potentially blinding and constitute an ocular emergency needing urgent treatment. they require immediate, copious irrigation of the eye and removal of particulate matter. the upper eyelids must be everted to ensure no particulate matter is trapped. In chemical injury associated with car battery explosion or firecracker injuries, consider concomitant injuries, including head injury, injury to periocular structures, thermal injury and blunt and penetrating ocular trauma. Chemical eye injuries require slit lamp examination and ophthalmologic opinion. Useful websites containing information about ocular emergencies are outlined in Resources.

Answer 6

Chemical injuries are graded on a scale of I–IV, based on corneal clarity and degree of limbal ischaemia. this grading determines ongoing treatment and indicates likely prognosis (Table 4).2,13 grade I and II injuries are treated with topical antibiotic drops or ointment (chloramphenicol) and ocular lubricants. grade III and IV are treated with an intensive regime including topical steroids, topical and oral ascorbic acid and topical citrate.

Feedback

the severity of a chemical eye injury depends on a number of factors including:

• the properties of the chemical

• the area of ocular surface affected

• the length of time the eye was exposed to the chemical (eg. ammonia causes anterior segment

Figure 12. Acid injury to the eye

Table 2. Common products containing alkali

Product Chemical

Plaster Calcium hydroxide

Oven and drain cleaner (lye)

Sodium hydroxide/potassium hydroxide

Fertilisers Ammonium hydroxide

Lime Calcium carbonate or magnesium carbonate

Table 3. Common products containing acid

Product Chemical

Toilet cleaner Sulphuric acid

Battery fluid Sulphuric acid

Pool cleaners Sodium hypochlorite

Bleaches Sodium hypochlorite

Rust removal agents Hydrofluoric acid

Table 4. Grading of chemical eye injuries2,13

Cornea Conjunctiva Prognosis

I Clear cornea, epithelial loss

No limbal ischaemia Excellent

II Hazy cornea, iris visible

Ischaemia 1/2 limbus Poor

Figure 13. Scarring of conjunctiva from previous chemical injury

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Case 4

Frank comes for his diabetes check upFrank is 56 years of age and was diagnosed with type 2 diabetes mellitus 6 years ago. after some initial enthusiasm, his attendances at the surgery for diabetes follow up have become more sporadic. He presents today in response to a reminder letter sent by the clinic for a diabetes check up. He feels tired but has no other complaints. On examination his body mass index (BmI) is 31.4 with Bp 142/84. His visual acuities are 6/6 corrected in each eye with normal visual fields. His most recent glycated haemoglobin is 7.9%, his total cholesterol/high density lipoprotein ratio is 5.1 and his albumin creatinine ratio is 1.2. He has recently seen the dietician but his last ophthalmologist review was 3 years ago. at this time, no retinal abnormality was found. His current medications include metformin 1 g three times per day, perindopril 5 mg per day and atorvastatin 20 mg per day, which he takes most of the time.

Question 1 Why is it important to screen for diabetic retinopathy (DR)?

Question 2 How does DR cause blindness?

Question 3 What are the risk factors for development of DR?

Question 4 How can you, as Frank’s gp, help Frank to prevent blindness from DR?

Question 5 How often should Frank be screened for DR?

Question 6 How should Frank be screened for DR?

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Case 4

Answer 1

Diabetic retinopathy is the leading cause of preventable blindness in adults worldwide.16 It is important to screen for it as detection and appropriate treatment can prevent nearly all severe vision loss and blindness.17 according to data from Bettering the Evaluation and Care of Health research, type 2 diabetes is managed at an average of 2.9 per 100 encounters in general practice, with ophthalmologists being the most common referral destination.18 the ausDiab study found that 15.3% of people with diabetes (type 1 and type 2) had DR.19 For those like Frank with type 2 diabetes mellitus, it is estimated that between 25% and 35% have DR,20 with around 6% having DR at the time the diabetes is diagnosed. treatment to prevent visual loss will ultimately be needed by 30% of people with type 2 diabetes mellitus and 50% of people with type 1 diabetes.21,22

Answer 2

advanced DR causes vision loss and blindness via two distinct mechanisms. the most common, diabetic macular oedema, occurs as the blood retinal barrier breaks down with subsequent blood vessel leakage and retinal thickening.23 the other mechanism is via proliferative diabetic retinopathy (pDR) where neovascularisation occurs in response to ischaemia. this results in bleeding of new and abnormal vessels. Visual loss is associated with vitreal haemorrhage or retinal detachment.23

Answer 3

the duration of diabetes is the strongest predictor for the development of retinopathy – the longer Frank has diabetes, the more likely it is that he will develop DR.22 Other associations include higher Hba1c, systolic blood pressure and dyslipidaemia.24

Answer 4

you can help Frank prevent blindness from DR by taking the following measures.

• Regular screening for DR and appropriate treatment if an abnormality is detected. Early detection of DR through screening, coupled with appropriate treatment can give impressive results. In one Swedish population of people with diabetes who had been appropriately screened over 23 years, only one person (out of 276) was found to be blind as a result of DR. the leading cause of blindness in this study was actually age related macula degeneration.25 laser photocoagulation remains the mainstay of treatment with reductions in severe visual loss by at least 50%20

• Helping him to maintain good control of his diabetes. maintaining good control of diabetes is always important, however, recent randomised controlled

trials aiming to maintain very tight blood sugar control have not demonstrated improved outcomes for DR and other microvascular complications26

• antihypertensives, statins and fibrates are useful medical therapies for reducing the progression of DR.20 Frank may benefit from the addition of another antihypertensive agent and an increase in his statin dose.

Answer 5

Screening recommendations vary according to pre-existing risk and retinal findings. Diabetic retinopathy is divided into nonproliferative and the more dangerous proliferative forms. Early nonproliferative DR includes microaneurysms and dot, blot or flame haemorrhages (Figure 14). moderate to severe nonproliferative DR includes hard exudates, cotton wool spots and venous beading (Figure 15). proliferative diabetic retinopathy and diabetic macular oedema are discussed above in Answer 2. the general recommendation is that patients with diabetes should be screened with a dilated fundus and a trained examiner every 2 years.20 However, many patients

Figure 14. Mild diabetic retinopathy

Figure 15. Moderate to severe nonproliferative diabetic retinopathy

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Case 4

local optometrists, contact your state branch of the Optometrists association australia (see Resources). appropriately trained gps and physicians can safely detect DR. a growing trend involves retinal photography in primary care,28,29 which has also been successfully used in the aboriginal and torres Strait Islander health context.30 teleophthalmology in conjunction with retinal photography is another option, especially for rural gps working where access to an ophthalmologist is difficult. this usually involves the transfer of a digital retinal image for ophthalmic assessment.20

like Frank have extra risk factors necessitating yearly screening as per National Health and medical Research Council recommendations (Table 5).20 Frank should have at least yearly screening owing to his hypertension and dyslipidaemia, assuming no DR is found.

Answer 6

Screening can be provided by suitably trained gps, optometrists or ophthalmologists. Ophthalmologists generally prefer biomicroscopy of a dilated eye with a special lens in conjunction with a slit lamp. Some doctors remain concerned about mydriatic drops owing to risks of acute angle-closure glaucoma. However, at a rate of 1–6 per 20 000 people, this is very uncommon.20 Direct ophthalmoscopy, even in the hands of ophthalmologists is a less effective screening tool owing to instrument limitations.20 Optometrists are another option and have been shown to have safe levels of sensitivity and specificity for detecting DR, internationally and within australia.20,27 For more information on services provided by local optometrists or if you need assistance linking in with

Table 5. NHMRC screening recommendations for diabetic retinopathy20

Population NHMRC screening recommendations

Children Screen at puberty

Women with diabetes who become pregnant Screen first trimester

Gestational diabetes Only screen if diabetes persists after pregnancy

Indigenous Australians Screen every year

Non-English speaking background Screen every year

Visual loss (other reason) Screen every year

Poor sugar control Screen every year

Hypertension Screen every year

Hyperlipidaemia Screen every year

Renal disease Screen every year

Long duration of diabetes Screen every year

Nonproliferative diabetic retinopathy is detected Screen every 3–6 months

Proliferative diabetic retinopathy or macular oedema is detected

Ensure they are seen by an ophthalmologist within 4 weeks

New vessels or vitreous haemorrhage Ensure they are seen within 1 week

Visual loss Need to be seen that day

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Michael has a unilateral red eyemichael, aged 27 years, complains of a red right eye. He says it feels irritated and that the light bothers him. He feels his vision is a little worse than normal in the irritated eye. He wears fortnightly disposable contact lenses and has done so for the last 4 years. He has no significant past medical or ophthalmic history. the practice nurse hands you a piece of paper on which she has documented the visual acuity in glasses as 6/9 in the right eye and 6/6 in the left.

Question 1 What differential diagnoses would you consider at this point?

Question 2 What further questioning would help to determine a cause for this presentation?

Question 3 How will you examine michael?

Further information

Fluorescein was instilled in michael’s right eye – the staining pattern is shown in Figure 16.

Question 4 What is the diagnosis and what would be your initial management?

Question 5 michael says he always gets cold sores when he is stressed. He asks whether stress also caused this presentation and whether there is anything he can do to avoid a recurrence. How will you answer michael’s query?

Case 5

Figure 16. Michael’s right eye after fluorescein staining

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Answer 1

michael has a unilateral red eye. the differential diagnoses for this problem are the following.

Microbial keratitis

Bacterial, fungal and amoebic corneal infections can occur in contact lens wearers. this is the most important diagnosis to exclude as it is potentially sight threatening.

Contact lens overuse

this is usually bilateral so less likely in michael’s case. It causes redness and irritation for a few days after removal of the lenses but this settles spontaneously.

Conjunctivitis

this can be bacterial or viral.

Herpes simplex viral (HSV) keratitis

HSV epithelial keratitis can present with irritation, photophobia and reduced visual acuity, especially if the epithelium over the pupil is involved. In australia, HSV keratitis is most commonly unilateral.

Uveitis

patients complain of a red eye with photophobia and reduced visual acuity. they may or may not have had previous episodes.

Corneal foreign body

this must be excluded in all cases of a unilateral red eye. most foreign bodies are metallic and can be corneal, conjunctival (including subtarsal) intraocular or penetrating.

Acute angle closure glaucoma

less likely in michael as this tends to occur in the elderly (in those with shallow anterior chambers).

Answer 2

Further questioning to determine a cause for michael’s presentation should be directed at confirming or excluding the differential diagnoses presented above.

Microbial keratitis

It is important to ask michael to describe in more detail the kind of sensation he is experiencing. patients with microbial infections have significant pain and irritation associated with reduced visual acuity. ask about contact lens hygiene, including cleaning regimen, prolonged use (>8 hours) and sleeping in contact lenses – poor contact lens hygeine is the most significant risk factor for microbial keratitis.31

Contact lens overuse

again ask about contact lens hygiene, particularly prolonged use (>8 hours) and sleeping in contact lenses as well as a history of recent change in contact lens brand.

Conjunctivitis

ask about recent upper respiratory tract infections as these can be associated with development of viral conjunctivitis. michael may also report contact with another individual with conjunctivitis. adenovirus is the most common viral conjunctivitis and is highly contagious. typically, patients describe a clear watery or mucoid discharge and may have noticed a tender preauricular node. Viral conjunctivitis can be bilateral but usually presents in one eye first. By contrast, the discharge of bacterial conjunctivitis is more likely to be described as ‘pus’: it is highly purulent and causes the lids to stick together in the morning. patients with bacterial conjunctivitis describe rapid worsening of symptoms (over a day) and swelling of the lid and conjunctiva (chemosis). a full sexual history should be taken: chlamydia and gonorrhoea can cause conjunctivitis.

HSV keratitis

ask about a previous history of HSV keratitis and whether he gets frequent attacks of oral or perioral cold sores.

Uveitis

ask michael about a history of ankylosing spondylitis, Hla-B27, uveitis, as well as sarcoid or inflammatory bowel disease (as patients with these conditions are at risk for developing acute anterior uveitis).

Corneal foreign body

ask about a history of foreign bodies in the eye, or of drilling or grinding without safety glasses. Secondary microbial keratitis may occur as a potential complication of organic or ceramic foreign bodies. It is important to ask about metal on metal work (ie. hammering on a chisel) as these may result in penetrating eye injuries with intraocular foreign bodies that require urgent surgery.

Acute angle closure glaucoma

In acute angle closure glaucoma, pain is significant and associated with nausea and vomiting.

Answer 3

In any eye presentation, visual acuity should be tested and documented as a poor Snellen visual acuity suggests a significant eye problem. this has already been done in michael’s case. Reduced visual acuity occurs in the setting of microbial keratitis, acute angle closure glaucoma, uveitis, and penetrating eye injury. In conjunctivitis, visual acuity is normal early in the process. In HSV keratitis the effect on visual acuity depends on the location and extent of the herpetic ulcer and may be normal or reduced. Further assessment should include the following examinations.

Case 5

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Case 5

Intraocular pressure test

In acute angle closure glaucoma intraocular pressure (measured with a tonometer) will be very high (>45 mmHg). most optometrists are able to measure ocular pressure if the gp does not have the requisite equipment. patients with acute angle closure glaucoma need immediate referral to an ophthalmologist.

Pupils

In conjunctivitis and corneal pathology, pupils should be equally reactive. a mid-dilated and poorly reactive pupil may suggest acute glaucoma. an irregular pupil may suggest acute anterior uveitis but this may not be evident until after the pupil is dilated. an irregular or distorted pupil, associated with poor visual acuity and subconjunctival haemorrhage or hyphaema may suggest a penetrating eye injury.

Conjunctiva

Conjunctivitis causes discharge (watery/mucoid or purulent depending on whether it is viral or bacterial) and diffuse injection confined to the conjunctiva – the cornea itself is clear. patients with viral conjunctivitis may have a tender preauricular node. In uveitis, the injection tends to be circumcorneal or perilimbal, called a ciliary flush and is suggestive of anterior chamber inflammation (Figure 17). Often, the peripheral or bulbar conjunctiva is not injected. patients with bacterial conjunctivitis may have significant lid swelling and chemosis.

Cornea

this should be inspected at higher magnification looking for corneal foreign bodies (Figure 18) and stained with fluorescein to determine the presence of corneal ulcers, abrasions or HSV dendrites. patients with uveitis present with circumcorneal injection. In microbial keratitis, corneal infiltrate may suggest an aggressive infective process (Figure 19). patients with infiltrate need immediate (that day) referral to an ophthalmologist. In acute angle closure glaucoma, the cornea will be cloudy. as a corneal abrasion (such as from contact lenses) heals, it may form a ‘pseudodendrite’, ie. have a dendritic appearance, because of the way the healing edges come together.

Eyelid

lid oedema and injection can occur with conjunctivitis. papillae (large broad based thickenings) are seen in bacterial conjunctivitis and follicles in viral conjunctivitis. It is also important to exclude subtarsal foreign bodies, so the upper eyelid should always be flipped and inspected.

The local anaesthetic test

the pain/irritation from superficial corneal problems (ie. corneal ulcer, foreign body) will be relieved by instillation of a single drop of local anaesthetic. Deeper pain from problems like uveitis will not be relieved.

Figure 18. A metal foreign body on the cornea

Figure 19. An abscess infiltrating the cornea – consistent with active bacterial keratitis

Figure 17. Acute anterior uveitis – there is anterior chamber inflammation, a ciliary flush and a fibrin plaque on the lens; the pupil has been dilated

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Case 5

Answer 5

patients with HSV keratitis often complain of being run down, tired or under stress. However, a prospective, randomised, double masked, placebo controlled, multicentre study found no association between stress and ocular HSV recurrence.33 topical steroid use can bring about an attack of HSV keratitis. For this and other reasons, it is important to use topical steroids sparingly in ocular disease and they should generally not be used in the general practice setting if the diagnosis is not clear or confirmed. It is important to explain to michael that he needs to disclose his history of HSV keratitis before a course of topical ocular steroids is ever recommended.

Answer 4

michael has a dendrite, which is typically branching and has rounded terminal bulbs. this is diagnostic of active HSV epithelial keratitis.

First line management includes:

• referral to an ophthalmologist as michael’s dendritic ulcer is over the visual axis. Referral to an ophthalmologist should be undertaken within 1–2 days if the dendrite is over the pupil as there is risk of anterior stromal scarring that may reduce final visual acuity

• ocular aciclovir ointment should be prescribed 5 times per day and the patient reviewed every 3–4 days. medication can be tapered by about day 7–10 and is continued for 3 days post complete resolution of the corneal ulcer.2,13

Debridement of the dendrite can also be considered. a drop of local anaesthetic is instilled and a sterile cotton bud is then used under magnification with a rolling motion to gently remove the involved segment of epithelium. this reduces the viral load and is believed to speed recovery. patients should be told to expect increased irritation and discomfort over a few days after this procedure.32

Feedback

Uncomplicated active HSV epithelial keratitis may be managed in the general practice setting. However, it is important to reassess every 3–4 days to look for development of any problems requiring an ophthalmologist review. the indications for referral to an ophthalmologist for assessment and management are:

• dendritic ulcer over the visual axis (as in michael’s case)

• significantly reduced visual acuity that may suggest deeper HSV stromal keratitis or iridocyclitis

• poor response to treatment; a persistent epithelial defect or ulcer

• presence of corneal infiltrate, suggesting a secondary bacterial keratitis.

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Case 6

Felicity presents with bilateral red eyesFelicity, aged 30 years, presents with bilateral red eyes. Her symptoms have been present for 2 days on this occasion, but she has suffered intermittent episodes over the last 5–6 years. Over the last 2 years they have become more frequent, with itch, watering, discharge and irritation. Usually each episode lasts 4–5 days with gradual improvement in symptoms but recently episodes have lasted 1–2 weeks. It is worse in the morning and better by the end of the day. Over the last 2 days she has been using an over-the-counter eye drop for red eyes, which she purchased from her local chemist. In a typical episode, she does not complain of photophobia and vision is unaffected. However, on this occasion, she notes that her vision is blurry in both eyes. there is no past history of ocular trauma.

Question 1 What differential diagnoses would you consider?

Question 2 What further questioning would help to determine a cause for this presentation?

Further information Felicity describes a history of hay fever relieved by antihistamines and says her eye symptoms sometimes happen at the same time as she has hayfever. She notices that the symptoms are worse if she hasn’t vacuumed in a while or is cleaning out dusty cupboards. She remembers having eczema as a child. She is on no medications and has no other illnesses.

On examination, you find:

•visualacuity6/6unaidedinbotheyes

•bilateralinjectedconjunctiva

•nocircumcornealflushing

•moderatesizedupperlidpapillae(Figure 20)

•stringymucoiddischarge

•mildlidoedemabutnocellulitis

•clearcornea

•mid-dilatedandslowlyreactivepupils

•fullextraocularmovements

•noglobeproptosis.

Question 3 What is the diagnosis? What could explain her blurred vision and mid-dilated and slowly reactive pupils?

Question 4 Would you refer Felicity to an ophthalmologist?

Figure 20. Felicity’s upper lid showing moderate sized papillae, chemosis and injection – there is excess fluorescein in the eye

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Case 6

Question 5 What is the management of the mild, moderate and severe forms of Felicity’s condition?

Question 6 What are the potential side effects of topical steroids?

Answer 1

Diagnoses that could explain her symptoms include the following.

Allergic conjunctivitis

this is the most probable diagnosis and mainly arises from type 1 hypersensitivity reactions to airborne allergens. Episodes can often be seasonal (grass seeds, pollen) or perennial (dust mites).

Atopic keratoconjunctivitis

this a rarer but serious adult condition and is related to a mixed type 1 and 4 hypersensitivity. Felicity may have associated lid eczema, tarsal plate thickening and lid and conjunctival chemosis (hyperaemic swelling). Keratitis may occur and for this reason patients need more aggressive treatment and prompt referral.

Episcleritis

this is usually of more acute onset and presents as a localised patch of redness on the eye white with minimal discomfort. photophobia and watery discharge may be noted.

Dry eye

this can be caused by poor aqueous tear production, or from tears not staying on the ocular surface long enough. Over time, and if untreated, the ocular surface may become damaged. the symptoms of dry eye include stinging or burning, local conjunctival irritation and a feeling of grittiness.

Acute anterior uveitis

Bilateral uveitis is possible but much less common. Symptoms include photophobia, irritation, pain and reduced visual acuity.

Pterygium

this is a fibrovascular band arising from the nasal limbus. these can be bilateral and can occasionally become injected and may disrupt the corneal tear film interface leading to surface irritation.

Viral conjunctivitis

this can be bilateral but it often starts unilaterally and then a few days later, progresses to involve the other eye. Vision is unaffected early but some patients may develop keratitis and need prompt referral.

Answer 2

Further questioning should include the following.

Allergic conjunctivitis

ask about a history of hay fever or seasonal allergy relieved by antihistamines and whether episodes of her eye symptoms are temporarily related to these symptoms. She may volunteer a known allergen. In uncomplicated allergic conjunctivitis, vision should be unaffected.

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Case 6

Answer 4

Felicity can be managed initially in the general practice setting. Indications for ophthalmologist referral in this setting include:

• the patient is not improving after initial management

• active keratitis

• the diagnosis is unclear

• the patient may require prolonged topical steroid therapy

• visual acuity is disproportionately reduced

• there is an active corneal ulcer associated with giant papillae.

Answer 5

management2,13,36 should consist of patient education, identification of the allergen and avoidance of the allergen if possible. However, most allergens (such as dust mites) are difficult to eliminate. pretreat with oral antihistamines on days known to have high pollen count. Employ the following measures.

Mild disease

Start with low viscosity ocular lubricants and cool compresses.

Moderate disease

prescribe topical mast cell stabilisers (eg. lodoxamide trometamol), topical antihistamines (eg. levocabastine hydrochloride), or a combined mast cell stabiliser and antihistamine (eg. olopatadine hydrochloride). these medications work well but effect may be delayed for up to 6 weeks.

Severe disease

add a short course of a moderate strength topical steroid for a short duration (ie. fluorometholone acetate three times per day for 1–2 weeks). If a patient needs to use steroids for more than 2 weeks, ophthalmology referral is required.

Answer 6

Common side effects of topical steroids can include intraocular pressure rises, cataract formation and secondary reactivation of HSV keratitis. For these reasons, topical steroids should be used judiciously and only for a short period of time.37 monitoring by an ophthalmologist is essential if the patient is to use steroids for more than 2 weeks.

Atopic keratoconjunctivitis

ask about a history of atopy and eczema. as a child she may have suffered from vernal keratoconjunctivitis, which is a severe form of type 1 hypersensitivity in children. She may have had previous lid staphylococcal infections and eczematous exacerbations as an adult. patients with atopic keratoconjunctivitis often develop an associated keratitis and therefore vision may be reduced.

Episcleritis

ask whether they have noticed a localised patch of redness on the white of the eye and watery discharge or photophobia.

Dry eye

In contrast to Felicity’s history, dry eye symptoms are often worse at the end of the day. they also tend to get worse in air conditioned environments and after prolonged periods of computer use, and improve with eye lubricants. It is important to ask about medications as some medications can exacerbate dry eyes including antidepressants, oral contraceptives and beta-blockers.

Acute anterior uveitis

patients with bilateral uveitis will often have systemic illnesses such as sarcoidosis, or a seronegative spondyloarthropathy. Rarer systemic infections (tuberculosis, syphilis, toxoplasmosis) need to be excluded in at risk patient groups.

Pterygium

ask about a history of working outdoors in high ultraviolet conditions.

Viral conjunctivitis

ask about contact with another person with viral conjunctivitis. adenovirus is the most commonly implicated virus. Over 50 serotypes of adenovirus have been identified.34 patients with active adenoviral conjunctivitis continue shedding virus for up to 2 weeks and are highly contagious. However, this is unlikely in Felicity as she reports multiple episodes in the past and viral reinfection is quite rare.

Answer 3

Felicity’s history and examination findings suggest a diagnosis of allergic conjunctivitis. the most likely cause of Felicity’s mildly blurry vision and mid-dilated and slowly reactive pupils is over-the-counter red eye medications containing vasoconstrictive agents. these work through local adrenergic mechanisms, which may pharmacologically dilate the pupil and in some cases (like Felicity’s) cause slow pupil reactivity.35 Reassuringly, Felicity has normal eye movements, this excludes a possible cranial neuropathy.

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Case 7

Jack has a squintJack, aged 5 months, is the first child to Betty, 32 years of age, and John, 34 years of age, born at term after a pregnancy marked by some first trimester bleeding. the maternal and child health nurse pointed out a possible ocular misalignment at the age of 3 months but said that Jack was likely to ‘grow out of it’ and did not recommend referral. Neither parent had ever noticed a problem with his alignment or visual function. Jack always responds to his mum’s presence and he seems to see well. Betty had treatment for childhood strabismus (glasses, patching and surgery). Betty has now noticed a significant misalignment (Figure 21). you notice the right eye turning in quite badly. you check the light reflexes in the pupils and see that it is quite central in the left eye, and very decentred in the right.

Question 1 What do you think is going on and what further history will help you to make a definitive diagnosis?

Further information Betty shows you the image in Figure 22 on her phone.

Question 2 What further information does this photo provide?

Question 3 What clinical feature of a squint has a major impact on prognosis?

Question 4 Was the maternal and child health nurse correct in suggesting that Jack will grow out of his squint?

Figure 21. Jack’s right eye turning in

Figure 22. Jack’s left eye turning in

Case 7

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Case 7

Question 5 How can you detect eye misalignment with a simple office test?

Question 6 How will you manage Jack?

Question 7 the three main treatments for childhood strabismus are glasses, patching, and surgery. What does each one do?

Question 8 Jack’s mum asks you whether Jack will look normal when he goes to school and whether he will read well and play sport well. She asks if he will be able to appreciate their new expensive 3D television. How will you answer her?

Answer 1

this appearance can be due to the following.

• Early onset convergent strabismus from so called ‘congenital’ esotropia. this is more accurately called infantile esotropia – it is hardly ever truly congenital, but is typically first noticed at ages 3–5 months

• accommodative esotropia – this is at least partly glasses responsive, and usually occurs in children aged 2–5. However, it can also be seen in the first year of life

• Sixth nerve palsy in childhood – requires urgent referral to a paediatrician or paediatric neurologist and usually imaging within a few days

• Retinoblastoma – a very rare intraocular tumour (requires urgent referral to a paediatric ophthalmologist).

It is important to ask whether it is always the same eye that turns in, or whether both eyes turn in (alternating). parents will often say (because they think) that ‘both eyes’ turn in when it is either one or the other. alternating esotropia usually means that the vision is developing equally (or nearly equally) in each eye and that there is no unilateral neurological lesion. alternating esotropia essentially excludes sixth nerve palsy and retinoblastoma (and the need for referral within days).

Other important aspects of the history include:

• prematurity (not relevant in Jack’s case) or a difficult perinatal course

• developmental delay (ie. ask about developmental milestones)

• family history of strabismus.

If Betty describes alternating esotropia, it is important to know whether it is easy for Jack to switch from left eye dominant (right eye turning in) to right eye dominant (left eye turning in). Because it is difficult examining babies’ eyes, it may be easier to ask Betty if she has a photo that shows the left eye turning.

Feedback

most patients with sixth nerve palsy in childhood have ‘sixth nerve paresis of unknown/uncertain cause’, thought to be of viral aetiology which is neurologically innocent and often recovers. a tiny number of these patients will have a serious neurosurgical cause.

Answer 2

the photograph indicates that the squint is alternating and is unlikely to be due to a sixth nerve palsy or an intraocular tumour. therefore management is semi-urgent rather than urgent.

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Case 7

Answer 6

Jack needs a referral to a paediatric ophthalmologist as he has esotropia beyond 4 months of age. there is always an appropriate rush to have the child seen quickly for a first visit because of the following:

• it is difficult for the nonspecialist to examine a child’s squint with confidence (it may also be difficult for the specialist) – and physician anxiety is added to parental anxiety

• there are rare associations with sinister conditions that can look just like regular strabismus

• the results of treatment are better if a child is realigned within a few months of constant misalignment.

Answer 7

glasses alone often improve alignment and vision if there is a significant refractive error (this is much more likely in a 3 year old than a 5 month old infant). If with the best glasses there is asymmetry of vision (amblyopia), patching the better eye to encourage better vision in the worse eye is required. Blurring the better eye with atropine eye drops has an equivalent effect. Improvement in alignment and vision occurs with conservative treatment in 75% of children. Surgery is required to align eyes after treatment with glasses and patching has been completed. Success rates of surgery vary with:

• age at surgery

• duration of follow up

• whether esotropia or exotropia

• associated features (eg. asymmetric refractive error, any developmental issues, and disorders such as attention deficit hyperactivity disorder are negative prognostic features).

Answer 3

the clinical feature of a squint that has a major impact on prognosis is whether it is intermittent or constant. Intermittent squints may get better, constant ones don’t.

Answer 4

this depends on whether the nurse saw constant or intermittent esotropia, or if she wasn’t sure whether she saw anything wrong. Intermittent esotropia in the first 3 months of life is common (around 30% of babies) and doesn’t need referral. Constant esotropia in the first 3 months of life is rare (

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Case 7

It is often necessary to use all three modalities (glasses, patching and surgery).

the overall aims of treatment are:

• good vision in each eye

• normal alignment and normal appearance

• the ability for the brain to assimilate the images from each eye into one, ‘binocularity’, which at its best means high quality 3D vision.

Answer 8

Expectations of normal appearance in the prep year are >90%.39 Children who don’t look normal at age 5–6 often get negative responses from other children their age – this can be difficult and detrimental for the child. Reading and playing sport does not require a perfect visual system. a child needs 6/15 vision to function normally in a school environment; if a child is 6/24 or worse they will usually need some assistance, such as from a part time aide. a ‘perfect’ visual system allows faster maximum reading speed, better performance at small ball sports, and the ability for high quality 3D. treatment should always aim for ‘perfect’ but ‘near perfect’ can be accepted as an outcome.

Feedback

See Table 6 for definitions of squints.

Table 6. Squint definitions

Term Explanation

Squint Any ocular misalignment

Strabismus Any ocular misalignment

Esotropia Convergent squint

Exotropia Divergent squint

Amblyopia Poor vision in one eye which may be reversible with glasses and/or patching and/or correctly aligning the eye/s

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Resources

check Ophthalmology

ProfessionalInformation on basic eye emergencies. Available at www.eyecasualty.co.uk

Useful eye videos. Available at www.rootatlas.com

Useful eye photographs. Available at www.redatlas.org

Optometrists Association Australia. Available at www.optometrists.asn.au

Therapeuticguidelines:antibiotic. Available at www.tg.org.au/index.php?sectionid=41

Patient InformationPatient information on common eye problems is provided by the National Eye Health Awareness Campaign. Available at www.health.gov.au/internet/eyehealth/publishing.nsf/Content/commonprob

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SGL and SCA kits are available with instructions on the RACGP website at www.racgp.org.au or by contacting a professional development officer at your state QA&CPD unit.Qa&CpD program requirements (2008–2010 triennium)

check Ophthalmology

Active learning moduleInordertoqualifyfor40Category1QA&CPDpoints for this ALM, please go to www.gplearning.com.au and complete the following steps online. If you have any queries or technical issues accessing the ALM, please contact the gplearning helpdesk on1800284789.

Alternatively, ALM forms can be downloaded from the RACGP website at www.racgp.org.au/check. Completed forms can be emailed to check@racgp.org.au or posted to the check coordinator. For ALMs not submitted online, please allow up to 6 weeks to receive your certificate of participation.

Step 1. Undertake this predisposing activity• Writeanswerstothefollowingquestions.

What are the differential diagnoses of eyelid lumps? How would you manage a patient with a chalazion and/or blepharitis? How does amaurosis fugax present? How would you investigate and manage a patient who presents with amaurosis fugax? What is the immediate management in the setting of a chemical eye injury? How do alkali and acid eye injuries differ? How are chemical eye injuries graded? What are the long term complications of chemical eye injuries? Why is it important to screen for diabetic retinopathy (DR)? How often should patients be screened for DR? What are the clinical features and recommended management of allergic conjunctivitis and herpes simplex virus keratitis? What are the differential diagnoses of unilateral and bilateral red eyes and the indicators of sight threatening disease in this setting? How would you assess an infant who presents with a squint?

• Developalistofatleastthreepersonallearninggoals for this ALM. It may be helpful to consider the following questions. Why did I choose this topic at this time? What would I like to do differently as a result of undertaking this ALM? What would I like to understand or appreciate more about this topic? What skills or knowledge would I like to gain?

Step 2. Read and complete this unit of check. You do not need to send in the completed check unit. Please retain this check unit and answers for your future reference. Expected time commitment is approximately 2 hours.

Step 3. Undertake one practice based activity and one community based activity from the list of suggested activities below. Choose one practice based activity from the following.• Facilitateaninteractiveworkshopatalunchtime

practice meeting on eye examination. Discuss the importance of checking and documenting visual acuity, and practice assessment for misalignment, eyelid eversion and corneal and conjunctival examination on each other and removal of foreign bodies on animal eyes from the local butcher if

available. Discuss the management of chemical eye injuries and make sure equipment for eye irrigation is available if necessary

• WithaGPfromyourclinicperformanauditofthe equipment for examination and management of eye problems in your clinic. Are Snellen eye charts available to all practitioners? Is the treatment room equipped with in date local anaesthetic and flourescein eye drops? Is Hartmann or normal saline solution available for irrigation? Does your practice have litmus paper to test tear pH? Make sure all the GPs in the practice know where this equipment is and how to use it

• WithaGPcolleaguefromyourpracticereview 10 recent diabetic patients. Were they screened appropriately for DR? Identify the best method for DR screening for your location (ophthalmologist, optometrist or GP) and your ideal referral pathway if an abnormality is detected on screening. Update your practice address book with these details

• Writeapatienteducationarticleforyourpractice newsletter on any topic relating to this unit of check, such as assessment and management of red eye, eyelid lumps, squint, allergic conjunctivitis or eye safety in the home and workplace

• Reviewpatienteducationmaterialyouhaveinyour practice on any topic relating to this unit of check and make up a resource folder of quality information and useful referral contacts in your local community

• Deviseyourownactivitythatutilisestheknowledge and skills you have obtained from this unit of check within your practice and address your personal learning needs.

This activity must involve at least a 2 hour time commitment and details must be submitted with your evaluation.Choose one community based activity from the following.• WithGPcolleague(s)fromanotherpractice

review the practice systems you use for screening and management of DR. Invite local optometrists and ophthalmologists to attend a divisional meeting to discuss referral pathways and how to optimise screening and management of DR in your location

• Contactyourmaternalandchildhealthservice and organise a meeting to discuss the management of squint in infancy and childhood. Invite a paediatric ophthalmologist if available

• Giveapresentationatalocalsportingclub,community organisation, school or workplace on a topic relating to this issue of check, such as assessment and management of red eye, eyelid lumps, squint, allergic conjunctivitis or eye safety in the home and workplace

• Writeapatienteducationarticleforyourlocalnewspaper on any topic relating to this unit of

check, such as assessment and management of red eye, eyelid lumps, squint, allergic conjunctivitis or eye safety in the home and workplace

• FacilitateaQA&CPDmeetingatyourlocaldivision on any topic relating to this issue of check. Invite local optometrists and or ophthalmologists to attend and participate

• Deviseyourownactivitywithinyourlocalcommunity that utilises the knowledge and skills you have obtained from this unit of check and addresses your personal learning needs.

The activity must involve at least a 2 hour time commitment and details must be submitted with your evaluation.

Step 4. Fill in the reinforcing activity and evaluation summaryReport on the activities and reinforcing activity, and provide us with your evaluation online via gplearning at www.gplearning.com.au. If you have any queries or technical issues accessing the ALM, please contact the gplearning helpdesk on 1800284789.Alternatively,ALMformscanbedownloaded from the RACGP website at www.racgp.org.au/check. Completed forms can be emailed to check@racgp.org.au or posted to the check coordinator. Please allow up to 6 weeks upon receipt of your evaluation summary to receive your certificate of participation.

check Category 2 QA&CPD activity In order to qualify for 6 Category 2 points for this activityinthisunit:• readandcompletethisunitofcheck, and • logontothegplearning website at www.

gplearning.com.au and answer the 10 multiple choice questions online.

Expected time to complete this activity is 3 hours. We encourage you to also complete the online evaluation for this activity.ParticipantscanbeawardedQA&CPDpointsforboth the ALM and Category 2 activity.

Other activities to consider for the QA&CPD ProgramSmall group learning (40 Category 1 points)Would you like to learn more about this topic with your peers? You could use this unit of check and the resources listed as the basis for small group learning. Ask other GPs in your practice or contact your division of general practice to find others interested in the same topic.Facilitator training is run regularly by RACGP faculties and will equip you to run the small group process effectively.Supervised clinical attachment (40 Category 1 points)Consider arranging a supervised clinical attachment with an eye clinic or eye hospital emergency department.

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… continued overleaf

QA no. _________________ Name ___________________________________________ Contact telephone no. ________________________

Address ________________________________________________________________________________________________________

Haveyoucompletedthisunitofcheck?Yes/No Timetakentocompletetheunit:__________________________________________

2. Reinforcing activity

Refer to your initial answers from the predisposing activity. What differences are there in your answers now that you have completed this unit of check?

What did you learn from this activity?

What will you do differently in your practice as a result of this activity?

1. Report on activities

Practice activity Write a brief description and attach evidence of the activity undertaken within your practice. Evidence includes minutes of meeting, photo of events, practice newsletter, proformas/guidelines/protocols developed and/or diary entries.

Community activity Write a brief description and attach evidence of the activity undertaken within your community. Evidence includes a letter of attendance from the community organisation that you visited, copy of newspaper article, flyer from community talk, diary entries of appointments and/or notes made of meetings.

Eligible for 40 Category 1 points in the RaCgp Qa&CpD program. a minimum of 6 hours is required to complete this alm excluding the time taken for predisposing and reinforcing activities. please complete all sections. Upon completion, email to check@racgp.org.au or post to the RaCgp, 1 palmerston Crescent, South melbourne, Victoria, 3205, australia. please retain a copy for your records.

check program 2010 alm

check Ophthalmology

Activity report and reinforcing activity Active learning module on ophthalmology (unit 460)

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Signed by participant ________________________________________________________________________________ Date __________________________

Office use only Approved Signed __________________________________________________________ Date __________________________

AttendanceforwardedtotheNationalQA&CPDUnitDate_______________________________

Evaluation1. Learning objectives

Please indicate to what extent after completing this activity you are able to meet the stated learning objectives.O

VE

RA

LL

EV

AL

UA

TIO

N

check program 2010 alm

check Ophthalmology

2. Learning needs and relevance to practice

Not Partially Entirely met met met

Rate the degree to which your own learning needs were met Not Partially Entirely relevant relevant relevant

Rate the degree to which this activity was relevant to your own practice

3. Other informationPlease rate the extent to which you agree with the following statements.

Statement Strongly Strongly disagree Disagree Agree agree

There was sufficient information and resources for me to complete this activity well

The writing and case histories were of a high standard This activity increased my knowledge/understanding of this topic I am likely to change my clinical practice as a result of this activity This activity was of benefit to other members of my practice

4. What other topics would you like to see covered in check?

5. Do you have any additional comments?

Not Partially Entirely met met met

Learning objectiveRecognise the clinical features of chalazia, blepharitis, allergic conjunctivitis and herpes simplex virus keratitis and manage these conditions appropriately

Appreciate that amaurosis fugax is a symptom of carotid artery disease with an associated increased risk of subsequent stroke

More confidently manage chemical eye injuries with immediate copious eye irrigation and removal of particulate matter followed by slit lamp examination and ophthalmologic opinion

Recognise the importance of screening for diabetic retinopathy to prevent severe vision loss and blindness

List the differential diagnoses of unilateral and bilateral red eyes and the indicators of sight threatening disease in this setting

More confidently assess and manage infants who present with squint

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check Category 2 Qa&CpD activity

check Ophthalmology

OphthalmologyIn order to qualify for 6 Category 2 points for this activity in this unit:•readandcompletetheunit•logontothegplearning website at www.gplearning.

com.au and answer the following 10 multiple choice questions (mCQs) online. If you are not an RaCgp member, please contact the gplearning helpdesk on 1800 284 789 to register in the first instance. you will be provided with a username and password that will allow you access to the test

•completetheonlineevaluation.Expected time to complete this activity is 3 hours. please do not send answers to the mCQs into the check office. this activity can only be completed online at www.gplearning.com.au.If you have any queries or technical issues accessing the test online, please contact the gplearning helpdesk on 1800 284 789.

Question 1

manuela, 45 years of age, presents with a pea sized lump in her left upper eyelid. She says she has always had trouble with her eyes and that they are often itchy and look like she is wearing pink eyeliner and has dandruff in her eyelashes. On examination, manuela has a firm, nontender, pea sized lump of the left upper eyelid. the surface of the lump is smooth and the overlying skin is mobile with no surrounding inflammation. you diagnose a chalazion. Chalazia:a. occur in the small sebaceous glands at the base of the

eyelashesB. may be complicated by internal hordeolum formationC. occur less commonly in patients with pre-existing

blepharitisD. rarely resolve spontaneouslyE. should be treated with cold compresses to reduce

inflammation.

Question 2

petros, 66 years of age, presents complaining of a brief episode of loss of vision in his left eye. His vision returned to normal after a few minutes. He felt otherwise well during the event and reported no associated features. He has a history of hypertension, hypercholesterolaemia, diverticular disease and alcohol abuse. He quit smoking after 30 years about 3 years ago. He has no personal or family history of cerebrovascular or cardiovascular disease and is not diabetic. He takes irbesartan/hydrochlorothiazide 150 mg/12.5 mg per day, simvastatin 20 mg per day, aspirin 100 mg per day. Eye and neurological examination is normal. His pulse was regular at 80 bpm, blood pressure 150/90, heart sounds normal and there is an audible bruit in the left carotid.

you explain to petros that:a. his presentation is probably caused by transient

hypoperfusion of the retina which is benign and requires no further investigation or treatment

B. his presentation is unlikely to be caused by temporal arteritis as this always causes headache and jaw claudication

C. he requires a blood test , an electrocardiogram and a carotid ultrasound

D. he is at low risk of subsequent stroke E. he requires warfarin in the first instance to prevent a

catastrophic stroke.

Question 3

the aBCD2 score was developed to predict which patients are at high risk of stroke within 7 days of having a transient ischaemic attack. given the above history, petros’ aBCD2 score is:a. 1B. 2C. 3D. 4E. 5.

Question 4

Sanjay, 20 years of age, works as a gardener. He was mixing some fertiliser and splashed some in both eyes. He has severe pain and cannot open his eyes. He has brought the bottle of fertiliser with him which says it contains ammonium hydroxide. Regarding chemical eye injury, which of the following is true?a. Eye irrigation should be avoided as this may spread the

chemical onto the surrounding skinB. ammonium hydroxide causes coagulative necrosis of

the cornea, which limits the ability of the chemical to penetrate the eye

C. alkali eye injuries tend to be less severe than acid eye injuries

D. grade I and II injuries are treated with an intensive regime including topical steroids, topical and oral ascorbic acid and topical citrate

E. prognosis depends on corneal clarity and the degree of limbal ischaemia.

Question 5

Boris is a 56 year old man who presents for a diabetes check up. He was diagnosed with diabetes 11 years ago. His diabetic control is good (Hba1c 6.8%). He says he is tired of all the appointments he has to attend because of his diabetes and asks if it is really necessary to have his eyes checked every 2 years if it is always normal. you ex