BlueSky, Optometry Victoria / South Australia’s biannual event, this year presented in both face-to-face and virtual format, was a massive hit with 450 people attending presentations at the Adelaide Convention Centre and online.
As always, this conference pushed optometrists to think beyond their day-to-day practise, and reminded them of the potential they have to change lives in so many ways. Here are a few snippets from the presentations delivered.
INTERNATIONAL RAPID FIRE
Herpes Simplex, Viral Conjunctivitis, Syphilis and More
Overcoming travel restrictions, Professor Blair Lonsberry and A/Prof Nate Lighthizer, two United States based optometrists who are regular BlueSky presenters, presented a virtual rapid fire session, drawing on five case studies to discuss a range of anterior and posterior segment conditions.
The first, presented by A/Prof Lighthizer, was a patient with an atypical case of herpes simplex limbitis virus with a dendrite keratitis. The patient had a red, achy eye, reduced corneal sensitivity, and a history of cold sores.
Herpes simplex is the most common virus found in adults, occurring in 60–99%, and is most often recurrent with episodes including stress, fatigue, and hormonal changes.
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Herpes simplex keratitis is a corneal infection with herpes simplex virus (HSV). Ocular manifestations are lid lesions with oedema, follicular conjunctivitis, and corneal epithelial lesions.
People under the age of 15 are unlikely to have herpes simplex, and A/Prof Lightizer and Prof Lonsberry both said they almost never see patients under 15-years with ocular manifestations of the virus.
Recurrent ocular herpes affects the cornea, often with epithelial dendritic keratitis. In diagnosis it is important to be able to differentiate a true dendrite from a pseudo dendrite which is typically not herpes simplex.
A true dendrite has ulceration and terminal end bulbs, and corneal sensation is reduced, whereas a pseudo dendrite is often elevated, the geographic elevation can be seen using a heat light behind the slit lamp.
Prof Lonsberry said timing is important when diagnosing HSV as the dendrite form and structure can change significantly over days. The classic dendrite is typically present as the first presentation of HSV keratitis but can progress to a geographic ulcer, especially in patients who are immunocompromised or taking topical steroids. He recommended staining with both sodium fluorescein and lissamine green/rose Bengal and putting both stains in at the same time as lissamine green/rose Bengal take a couple of minutes to stain properly. Look with the cobalt blue filter first, and look for staining with the sodium fluorescein and then flip to white light and assess staining with the lissamine green/rose Bengal.
Treatment for epithelial keratitis is topical or oral. Both are equally effective and there is no evidence to support combining the two.
Ocular herpes in children, though highly unusual, is likely (75%) to affect the stroma, which increases the likelihood of recurrence (80%) and will require steroidal treatment in addition to oral antiviral treatment.
Anterior Uveitis and Syphilis
Prof Lonsberry presented a case of bilateral granulomatous anterior uveitis as a result of syphilis. In Australia, syphilis is primarily among men having male-to-male sex in urban settings and in young heterosexual Aboriginal and Torres Strait Islander People in remote communities (The Kirby Inst 2016). This sexually transmitted disease is on the rise globally with an increase in Australia of 135% between 2013 and 2017. Incidence of syphilis has dramatically increased in Victoria in recent years, and there have been several cases of babies dying as a result. As a notifiable disease, cases of syphilis must be reported to the Health Department, which makes testing of suspect cases essential.
In Australia, most laboratories do a treponemal test first which tells you whether the patient has been exposed to the treponema organism. If positive, this will be followed up with a non-treponemal test (e.g. RPR – rapid plasma regain) which identifies if there is an active infection and provides serum titre levels which are important in the treatment process.
The signs/symptoms of syphilis can go unnoticed in the early stages particularly in the primary stage which presents classically as a painless chancre sore at the site of entry of the treponema organism. Most people get diagnosed in the secondary stage as they typically develop a rash in unusual places including palms of the hands, soles of the feet or on the back. If a patient presents with a uveitis secondary to syphilis it is classified as neuro-syphilis and can present at any stage of syphilis (primary, secondary or tertiary).
Treatment in all stages of syphilis is with an intramuscular injection with Penicillin G, 2.4 million units in a single dose, which provides continuous levels in the tissues for up to a month, which are necessary for the treatment of the treponema organism.
ALZHEIMER’S DISEASE DETECTION
Eyes are increasingly recognised as being ‘windows’ to the body’s health. By examining eyes we can often detect signs of conditions, even when they are in their pre-clinical stage.
One of these diseases is Alzheimer’s disease (AD) which, as optometrist Dr Jeremiah Lim explained, is the most common cause of dementia accounting for about 70% of all dementias. One in five people develop AD by the age of 85 and, by 2060 it is expected to become the most expensive disease to manage in Australia. People can have preclinical signs of the disease as young as 50 yearsof- age and from there it can take up to 20 years for symptoms to develop. By the time a patient is formerly diagnosed, the disease is often late stage and they have lost a lot of independence. Public health initiatives are encouraging people to reduce their risk factors for AD by ceasing smoking and modifying diet.
Currently, the gold standard way to diagnose AD is to stain the brain during a post-mortem autopsy. Existing brain biomarkers such as PET-imaging or cerebrospinal fluid assessment are either expensive, inaccessible or invasive. However, through retinal examination, optometrists and ophthalmologists are able to detect biomarkers of AD hallmarks, namely the amyloid and tau protein.
In healthy eyes, amyloid precursor protein (APP) plays an important role in synaptic formation and maintenance. However, under certain conditions, abnormal proteolysis of APP leads to the formation of sticky soluble isoforms (Aβ40/42), which clump together to form amyloid plaques. Under the influences of amyloid, tau protein – which is important for cellular structural support e.g. retinal nerve fibre layer cells – hyper phosphorylates, resulting in tau tangle formation.
Due to the transparent media of the eye, eye care practitioners possess imaging tools that far exceed the resolution of existing brain imaging methods. This increases the likelihood of detecting abnormal changes occurring in neurons of the eye before they manifest in the brain or symptomatically, making the eye an attractive and accessible biomarker for AD.
Vascular changes in the eye using either fundus photography, or newer techniques such as enhanced depth imaging (EDI) and optical coherence tomography (OCT), are already proving to be useful in detecting early AD. Axonal losses in the retina measured non-invasively using OCT, have already been shown to be useful in detecting AD at various stages of the disease. While potentially useful for progression monitoring, these ‘topographical’ biomarkers reflect the ‘trail’ of damage left behind by amyloid and tau proteins but do not directly examine the underlying pathology, explained Dr Lim.
In recent years, there has been a push towards the development of ocular ‘pathological’ biomarkers which directly reflect AD hallmark levels, thus increasing specificity for AD diagnosis. One such example in development is the direct visualisation of curcumin-bound amyloid pathology using short-wavelength auto fluorescence. Another more recent innovation in this space is the use of hyperspectral imaging which allows for the non-invasive detection of increased soluble protein (i.e. amyloid, tau) concentration as seen in AD. The advantage of the latter is that it does not require the administration of extraneous tagging agents. As pathological biomarkers can potentially detect the disease up to 20 years before symptoms manifest, this is a very promising area for future ocular biomarker development.
As imaging technology improves, along with greater understanding of the eyebrain connection, Dr Lim believes that optometrists and ophthalmologists will play an increasingly important role in the diagnosis and co-management of neurological diseases such as AD and Parkinson’s disease.
RESPECTING THE VISUAL FIELD
Neuro ophthalmologist and Flinders University clinician scientist, A/Professor Celia Chan, spoke about visual field defects and shared pearls on what is neurological and what is not.
Dr Chen, a regular presenter at BlueSky, said one of the reasons for her love of neuro-ophthalmology is that “everything has its place” and the visual field is a classic example of localisation.
A visual field that respects the horizontal midline (i.e. the patterning is contained either above or below the midline) is likely to involve the optic nerve or the occipital lobe.
Visual field patterning that respects the vertical midline (i.e. the pattern is either to the left or right of the vertical midline) is retrochiasmal. In these cases, you must watch for pattern deviation and congruity.
Additionally, Dr Chen said she always examines both eyes rather than just the presenting eye – a condition may be occurring in both eyes (bilateral or sequential), or there may be a history in one or both eyes that the patient has forgotten about / forgotten to mention, that will provide important clues for the correct diagnosis. She presented examples of bilateral sequential non-arteritic anterior ischemic optic neuropathy that resulted in altitudinal visual field loss that respects the horizontal midline.
Using case studies, she demonstrated her point, focussing particularly on visual field reports. She also discussed the mimickers that may simulate bitemporal hemianopia patterning. To ensure you get an accurate visual field report, she advised optometrists not to be afraid to tape a patient’s eye lid up if it is drooping.
In a sign of the times, which has encouraged increased ‘home tourism’, Dr Chen reported the case of a patient who had swum (in a cage) alongside crocodiles in the Northern Territory.
Following the swim she had experienced dizziness and felt so unwell that she presented at a tertiary hospital and complained of vision change with difficulty reading. She had 6/6 vision, no relative afferent pupil defect and an Ishihara score of 15/15 in both eyes. Examinations showed nothing untoward until she was referred to Dr Chen who observed, on visual fields, a spot on each eye, right near the point of fixation. A small defect in both eyes that respected the vertical midline and were congruous suggested a neurological condition affecting the tip of the occipital lobe and uncovered an underlying vascular defect.
BlueSky Keynote: Making an Impact
The keynote speaker for BlueSky was Dr James Muecke AM, 2020 Australian of the Year. An ophthalmologist and the founder of Sight For All, Dr Muecke delivered two entertaining presentations, during which you could have heard a pin drop. He spoke first on social entrepreneurship and secondly on issues associated with type 2 diabetes.
Dr Muecke said his interest in social entrepreneurship was triggered when, as a medical graduate, he quickly became “disillusioned about treating chronic self-inflicted diseases, that shouldn’t even be seen”.
During his internship, he saved enough money to volunteer as a general doctor in Tumutumu Hospital in Kenya, East Africa.
“It was a year that changed my life – and also nearly ended my life,” he said entertaining the audience with brief descriptions of his experiences with capture by rebel soldiers, malaria, civil war, violent house robberies, and animal attack.
Dr Muecke described a social entrepreneur as someone who innovates for a sustainable solution to a social problem.
Being a social entrepreneur requires a:
- Spirit of adventure,
- Humanitarian spirit, and
- Entrepreneurial spirit.
“You’re filled with a burning desire to make a difference – that’s when your entrepreneurial spirit needs to kicks in. An entrepreneur needs to be a creator, communicator, leader, innovator, problem solver and risk taker. A social entrepreneur needs to innovate to achieve a social vision,” he said.
With over 40 million people in the world living with blindness, 90% of which is preventable, Dr Muecke said that having a BHAG is essential.
BHAG being an acronym for a Big, Hairy, Audacious Goal.
For Sight For All, the BHAG is to ‘create a world where everyone can see’. To do this, the organisation is focussed on educating and equipping colleagues in areas of need to both treat patients and advocate for preventative action. Dr Muecke went on to detail some of the programs in place and the extraordinary achievements in countries like Myanmar where Sight For All’s ‘teach a man to fish’ philosophy is now seeing the eye specialists they’ve trained training other eye specialists on the ground and treating tens of thousands of people each year.
THE T2D EPIDEMIC
Dr Muecke went on to speak about Type 2 diabetes (T2D), how it has arisen, why it is a growing epidemic, and the strategies to curb its rising threat to our health system and society.
At its core, T2D is due to too much sugar in our diet – not just sugar in our coffee and cakes, but sugar in our refined carbohydrates – white bread, breakfast cereals, pasta, white potatoes, white rice, etc., which he said are all “nutrient poor and non-essential”.
Despite being of no value to the body, these processed carbohydrates are recommended in the Australian Guide to Healthy Eating,1 something Dr Muecke strongly disagrees with.
Dr Muecke spoke about the “complex metabolic process” that occurs as the body tries to cope with excessive refined sugars and the impact this has on the body. He said it takes about 13 years for an adult and a couple of years for a child to develop lifechanging and life-threatening T2D.
“From 2016, when we began giving anti- VEGF injections for diabetic macular oedema, to the end of 2019, there was significant growth in the number of injections given, which mirrors the growth in type 2 diabetes. Over 100,000 injections are given each year in Australia, a treatment for a disease and a complication that should not be happening at all – I find this unbelievable,” he said.
Emphasising the devastating impact of T2D, he said “The number of deaths in Australia due to T2D over the past year is 15 times that of COVID-19 and the disease costs our health system at least AU$20 billion per year. This cost is probably closer to $100b when you factor in the cost of the other diseases that T2D leads to.
“In Greater Western Sydney, 50% of adults have T2D or pre-diabetes. We have over 1,100 kids and teens with T2D and close to 40,000 young adults.”
Being a dietary disease, Dr Muecke said there should be a dietary cure but there are a number of barriers which he refers to as the five As:
Addiction (sugar is highly addictive, triggers dopamine release in the brain),
Alleviation (use it to alleviate stress, make us feel better when we’re down),
Accessibility (highly visible in retail stores, service stations etc.),
Addition (an enormous amount of sugar is added to our foods; processed foods are cheap, especially in remote centres; and our health star rating system is flawed with a number of inherently unhealthy products, such as orange juice [until recently], getting a high rating), and
Advertising (our world has been flooded with advertising for years).
“We need to deal with these five A’s – we need to be aware, businesses and industry need to be accountable, we need to do the right thing by the people of Australia,” Dr Muecke said. He added that a levy on sugary drinks would be an effective step in conjunction with other strategies; this has been shown to reduce consumption of sugary drinks in 17 countries and could raise hundreds of millions of dollars that could be directed towards funding health awareness programs.
Dr Muecke went on to discuss other steps that could be taken to help stem the growth of T2D and its impact on the community, the health system and the economy.
Reference
- www.eatforhealth.gov.au/sites/default/files/content/ The%20Guidelines/n55i_australian_guide_to_healthy_ eating.pdf
