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Report

Unique perspectives and hard truths highlight Super Sunday

04/06/2018By Lewis Williams PhD
The wide variety of speakers at this year’s Super Sunday delivered a point of difference and resulted in some fascinating presentations. LEWIS WILLIAMS recaps a few of his highlights in part two of his special report.

The number of delegates at this year’s event represented around one-third of all registered NSW optometrists, while several interstate delegates also made the journey, not just for the conference part of the weekend’s program but also for the workshops the day before.

Reconnecting has become something of feature at such events and many meetings between professional colleagues, classmates, and those sharing common professional interests were evident on the day. Unfortunately, the packed program, with no formal allocation of a lunchtime, translated to reconnections that were necessarily brief.

Dizziness, disequilibrium and vertigo

Sydney-based neurologist, Clinical Associate Professor Peter Cremer, delivered a different but engaging presentation on vertigo and related issues, areas he specialises in.

To underline the ability of the eye-brain ‘system’ to provide good vision Cremer likened eye movements to camera shake and said the fact that we see a stable image is proof of the efficacy of that system. The vestibulo-ocular reflex (VOR) – the control of the eyes’ fixation to produce stable vision in which rapid eye movements in the opposite direction are central to a successful outcome – is the fastest response in the body, taking just seven milliseconds to act.


"Statements such as “the world is blurred” need additional questioning to differentiate possible causes."
Phillip Cremer, Sydney-based neurologist

According to Cremer, statements such as “the world is blurred” need additional questioning to differentiate possible causes, e.g., refractive, pathological, or motion-related. A head impulse test, also known as a head thrust test, should be performed to confirm an effective VOR. To achieve this, the patient is instructed to fixate a distant object, following which the practitioner grasps the patient’s head between both hands and turns the head firmly, and without warning, to one side or the other.

The eyes will compensate almost immediately, maintain fixation, and the patient will not report any blur if the VOR is intact. Forced oscillation of the head from side-to-side should not cause any problems either.

Unilateral ear problems can also be uncovered by a rapid head impulse test. Signs of vestibular problems can include nystagmus, smooth following eye movements, or a slightly delayed flick of the eyes to regain disturbed fixation. Bilateral vestibulopathy occurs when the balance function of both inner ears is defective, leading to both balance and visual problems that are typically worse in the dark or when footing in uncertain.

Cremer explained that this condition can be revealed with the use of a Romberg Test. The test involves asking a standing patient to close their eyes, with a subsequent deterioration of their balance interpreted as a positive Romberg Test, as before eye closure, the patient’s vision and vestibular function assisted their apparent balance.

However, if they have vestibular problems, some of their problems may also be apparent before applying the key part of the Romberg Test (eye closure). Additionally, pushing or prodding the patient adds to their difficulties.

Some patients can have decreased vision, to the extent of 6/36, when their head is moving (i.e., decreased dynamic vision) but can demonstrate 6/5 vision when their head is stationary. In some patients, simply oscillating their head can lead to a 1–2 line reduction in VA – oscillopsia.

Nystagmus

Nystagmus comes in many forms. In cases of recent vestibular problems, the eyes can flick in one direction and perform a drift return in the opposite direction. Other cases have symmetrical, jerky eye movements without noticeable effect on their VA. Yet other cases adapt to their difficulties by, in effect, taking snapshots of their vision at both extreme ends of their eye movement and assembling a stable image of their environment.


Some people demonstrate some form of nystagmus when their eyeballs are near or at their extremes of movement, and not all nystagmus is horizontal. Downbeat nystagmus in primary gaze can occur in cases of cerebellar degeneration, leading to complaints of poor vision and other disturbances. Their condition is usually worse in extreme down and/or lateral gaze.

Prisms might be found useful and a medication is available, but it has significant side effects.

In cases of brainstem problems, e.g., in MS, those affected can have upbeat nystagmus in one eye and downbeat nystagmus in the other. In cases such as Parkinson’s disease or Friedreich’s Ataxia, an adverse reaction to some medications can result in the brain switching off during eye movements to avoid the blur that would be created otherwise.

Furthermore, bilateral lateral recti function reduction can occur in meningitis, while internuclear ophthalmoplegia – impairment of adduction in the affected eye – results in horizontal diplopia.

In MS and stroke cases, the sixth (abducens) and third (oculomotor) nerves can be affected, and the eye’s adductions can be seen as slow eye movements. Vertical incapacities can also be induced, but adopting unusual head movements or attitudes can sometimes compensate for this, and the vestibular function can remain normal.

Less common conditions associated with neuromuscular junction problems were also mentioned. Those listed were; progressive supranuclear palsy (PSP), a degenerative disease that causes the patient to lose balance, lunge forward when starting to walk, bump into people and objects, and fall down, with later signs and symptoms signs becoming dementia-like; Miller-Fisher Syndrome, a nerve disease more common in men which results in slow voluntary eye movements, abnormal muscle co-ordination, and later, eye muscle paralysis and loss of tendon reflexes; and Myasthenia Gravis, sufferers of which are easy to fatigue and have skeletal muscular weakness, including of the breathing and motor muscles as well as eye and face musculature.

Vertigo


According to Cremer, benign paroxysmal positional vertigo (BPPV) is the number one cause of vertigo with an inner ear aetiology. Head movement or simple changes in head position can cause a spinning sensation for patients with BPPV, especially when rolling around in bed or when arising in the morning.

The main test for BPPV is a Dix-Hallpike Test – the patient is lowered quickly onto a bed, body facing upwards, and the head turned towards the affected side by 45°. The patient’s neck is then extended by the practitioner over the end of the bed so that the head, still turned to the side 45°, is lower than the body at around 30° to the horizontal (below).

The test is positive if the patient reports vertigo and the practitioner observes nystagmus, both of which can be delayed by several seconds after attaining the intended position. The condition is more common in those over 55 years of age, and the patient should be advised to avoid lying/sleeping on the affected (dizzy) side.

Benign positional vertigo (BPV) is the dizziness or vertigo experienced when changing position quickly, e.g., getting out from under a car, hanging washing on a high line, or getting out of bed. Loose positional crystals (calcium carbonate) floating in the semi-circular canals, especially the posterior canal, results in confusing positional messaging being sent to the brain about the body’s position.

The treatment for BPPV and BPV, Epley’s Manoeuvre, is simple. Essentially, a Dix-Hallpike Test is commenced and the head is positioned 45° towards the affected side and 30° below the body line for 1–2 minutes. The head is then rotated 90° in the opposite direction and held for a further 1–2 minutes. While maintaining that head and neck position, the whole person is rolled onto their shoulder, which in effect means the head is now 90° different from its previous position (45° downwards), and that position is maintained for another 1–2 minutes.

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Lastly, while maintaining the rotated head position, the patient is brought upright slowly and holds that sitting position for at least 30 seconds. Usually, the process is repeated two or more times. While it has a high success rate, the patient should be advised not to sleep on the affected side for a month or more after ‘treatment’.

Facts and knowledge

Reiterating that science was about facts and knowledge, Maloof then moved to randomised clinical trials (RCTs), the null hypothesis (proving something is wrong or unlikely rather than right) underlying the statistical basis of trial outcomes, and of course, evidence-based medicine (EBM). Maloof also alluded to ‘p-hacking’ – the massaging of data and subsequent analyses, while manipulating the probability value (p) to seek a desired, preordained outcome. That problem led the journal Nature to publish an article about the misuse of p.

EBM is not to be confused with its seven alternatives, as published in December 1999 by Clinical Professor David Isaacs in the British Medical Journal. The alternatives are: Eminence-based medicine, wherein the more senior the opinion leader, the more likely their output is to be accepted; vehemence-based medicine – the louder or greater the brow-beating, the greater the acceptance; eloquence-based medicine – the more impressive the proposer, the greater the acceptance; providence-based medicine – if clueless, resort to religious beliefs for decision making; diffidence-based medicine – do nothing out of a sense of despair; nervousness-based medicine – fear of litigation drives over-investigation and overtreatment; and finally, confidence-based medicine – which, according to Isaacs, is restricted to surgeons.

Maloof explained that misinformation (he used a much less charitable term) repeated incessantly can lead to acceptance ultimately, in what amounts to a case of the blind leading the blind. Turning to scientific corruption, he described feasance (the good) as to know, to understand, and to think, and malfeasance (the bad) as the spreading of misinformation, and to mislead. He also issued a warning to his audience to be wary of buzzwords used within medical contexts, such as stem cells, nano, laser, and quantum.

Maloof next directed his ire at the use of the term ‘dry eye’ when dryness is not the issue, but did not offer a suitable alternative, as admittedly, ‘hyperosmolality eye’ or ocular surface disease do not have quite the same ring to them. In a nod to Isaac’s seven types of medicines, Maloof introduced his own term – science-based medicine (SBM) – to describe the use of IPL in so-called dry eye, as while it is not EBM (not yet anyway), it is SBM currently.

Although an early user of CXL, Maloof is no longer a fan of the procedure, despite being a specialist keratoconus surgeon. He also noted in passing that with increasing age, the stromal collagen fibrils become cross-linked naturally and that just what CXL does to the cornea has not been established with any certainty, despite the CXL procedure being approved in more and more jurisdictions over the past decade.

His main issues with CXL are that it does not strengthen the cornea (but might make it more rigid), is not that predictable, and thins the cornea with deleterious effects on the stroma and the keratocytes within. In finishing, Maloof relayed some parting advice to keratoconics and potential keratoconics alike – “Don’t rub!”.

And now for something completely different


The keynote address delivered by Sydney ophthalmologist and oculoplastic surgeon, Dr Anthony Maloof, was definitely the most ‘out there’, but interesting, presentation of the day. Titled ‘Do myths exist in clinical practice?’, it had overtones of the ‘philosophy of medicine’ and raised the important issue of the damaging effects of pseudoscience. Anyone that does not believe the latter exists only has to watch commercial television for a brief time and take note of the range of ‘complementary and alternative medicines’ (CAMs) offered and the wealth of benefits they may have, might have, could have, but probably don’t have.

Given the proposed changes to the TGA’s advertising code with regard to CMS, Maloof’s presentation took on increased relevancy. His lecture then became one of epistemology – the process of acquiring knowledge. Maloof sees himself as a ‘probabilist’ – a medical professional capable of converting scientific thinking into novel patient care, while altering patient perceptions about what can be achieved.

Confounding professional relevance are factors such as: ‘promoted’ care, the wide availability and acceptance of pseudoscience, the biases that still exist in science, adherence to beliefs (especially long-held ones), widespread but poorly founded acceptance of what becomes dogma, and attitudes that follow “I did my research” that can lead to either a better understanding at best or medical blasphemy at worst. Perhaps the most telling of all is asking the wrong questions deliberately in the hope of getting the ‘correct’, or should that be the desired, answer(s).

In the meantime, patients, not unreasonably, assume that their practitioner(s) understand their needs comprehensively. At this point in his presentation, Maloof recommended the recent (2017) book The Death of Expertise by Tom Nichols which documents, among many other things, the campaign against established knowledge and the characterising of experts as ‘elitists’, much of which can be detrimental to society. Beliefs were based largely on a ‘don’t need to/didn’t check it’ model.

Information models range from: dogma, anecdotes (Maloof noted that the plural of anecdotes was not ‘data’, a common misconception among many), facts, laws of logic, truth, validity, reality, information, knowledge, understanding, and justification. Big groups tend to conform to ‘what’s out there’, tend to develop cognitive biases, can become beholden to false claims, and can begin to confuse familiarity with veracity. He believes an ongoing issue is that current training programs fail to teach students how to think.

Maloof also raised the problems surrounding predatory journals and publishers, what was first catalogued in ‘Beall’s List’ (a one-man effort). However, this was soon removed because of legal threats from those named and subsequently replaced by the more robust Cabell’s New Predatory Journal Blacklist in 2017.

More reading: Special Report Part 1: Super Sunday lives up to its name
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