Each year Optometry Victoria’s annual Southern Regional Congress (SRC) brings together a wide range of international and domestic speakers. Held at the Pullman Mercure Melbourne Albert Park centre on May 27–28, SRC welcomed international keynote speakers Dr Jim Thimons (Fairfield, CT, USA) and first time presenter Dr Ben Gaddie (Louisville, KY, USA).The other speakers were an assortment of noted Australian ophthalmologists and optometrists supported by representatives of various organisations and service providers, while the trade show area featured 33 exhibitors.VR – The fun way to tackle binocular vision problsVivid Vision founder Mr James Blaha started the virtual reality company that specialises in the treatment of amblyopia and strabismus after becoming frustrated with his own struggles with the conditions. With assistance from noted binocular vision research labs in the US, the technology has evolved and is now being offered in 84 clinics worldwide.{{image9-a:r-w:400}}Mr Manish Gupta, the company’s chief technical officer, and optometrist Dr Tuan Tran made presentations in the absence of Blaha. As chief of optometry, Tran is responsible for the clinical and educational aspects of the company’s activities. Gupta defined amblyopia as 6/12 or worse vision, or a difference of more than one line in VA for no apparent reason.While strabismus prevalence was given as about 5% of the population, binocular vision (BV) probls were said to afflict more than 10%, some 60% of which rain untreated. Some local estimates put the number of Australian amblyopes and/or strabismics at 1.15 million, which in a population of almost 24.5 million is a significant issue.The Centre for Eye Research Australia estimates strabismics alone at between 3% and 5% (735,000–1.23 million). While patching is the first line of treatment, it has been estimated that more than 40% of cases are unsuccessful and as soon as treatment ceases, many improvents regress soon after.Quoting the PEDIG ATS5 study, 2–6 hours of patching gave similar results to the less popular full-time alternative. The later ATS18 study compared anaglyphic separation in a computer game setting (Tetris-like, on an iPad) using just one hour per day at least a minimum of four days per week, with two hours per day patching, seven days per week. The computer game produced somewhat inferior results to patching.Although strabismus surgery is the third-most common eye surgery procedure, a complicating factor is the frequent need for second or even third rounds of treatment to address the probl. A further probl with strabismus and amblyopia is their effects on family life. Parents are cast in the role of physician, supervisor, and coach outside the consulting room, which can upset existing family arrangents. It has also been shown that 72% of strabismic patients are more likely to exhibit or express feelings of sadness.The Vivid Vision syst is offered as an alternative and provides contrast control, dichoptic presentation, and controlled, virtual, prismatic effects. Essentially, a process of conceptual learning is ployed and variable contrast is used to treat suppression. The deeper the suppression, the lower the contrast presented to the better eye and the higher the contrast to the suppressing eye.In studies conducted by Professor Dennis Levi from UC Berkeley’s School of Optometry, the virtual prism function was used to project stimulating images onto corresponding retinal points in each eye as a starting point to treatment. Treatment regimens varied from totals of 20–40 hours for two hours per day using a so-called first-person shooter game paradigm. Results of a pilot study were encouraging and are being pursued further. Interestingly, more conventional, non-action game paradigms were less effective.As was the case with the Vivid Vision creator, stereopsis can be achieved for the first time in many cases using the syst. One radical approach to the probl of entrenched amblyopia and/or strabismus in an ophthalmological setting was an attpt to ‘reset’ the vision and BV systs by keeping the patient in total darkness for 10 days consecutively and following that ‘resetting’ with use of the Vivid Vision syst to start anew.Many thousands of patients have undergone, or are undergoing, treatment with the syst and more than 10,000 patient enquiries have been fielded by the company. Refractive amblyopia can take 3–6 months of treatment for just one 30-min session per week, whereas strabismus can take 3–12 months of such treatment.When questioned, Tran likened BV to riding a bike; the fundamental skill never leaves even when not reinforced. Early VR systs were capable of inducing motion sickness but newer systs with higher screen resolutions (2k per screen) and faster screen refreshment rates have overcome those probls.An audience mber with a known BV probl was invited to trial the syst and make comments. The capability of VR to engage the ‘patient’ was apparent almost immediately and the VR goggle output was mirrored on the main screen so that delegates could relate the ‘patient’s’ reactions to what was being viewed. The gaming approach is almost certain to enhance compliance, a constant probl in vision therapy.
KEYNOTE SPEAKERS |
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 Tuan Tran |
 Simon Chen |
 Manish Gupta |
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Urgency of referralAssociate Professors Andrew Symons and Daryl Guest gave a presentation on optometrical referrals to ophthalmologists involving retinal pathology. Symons is a medical retina specialist who also has a PhD in genetics, while Guest is a senior faculty mber of the Department of Optometry, UniMelb, a long-time fixture in the Melbourne optometric eyecare and education scene, and a current mber of the Optometry Board of Australia.Seeking a second opinion or the need for additional treatments were given as the main drivers of referrals, and it was agreed that ophthalmologists and optometrists often had differing perspectives on the same cases. To some extent, treatment options, including none, govern referral behaviour. Cases aired during the presentation confirmed the assertion that the predictability of VA based on retinal appearances and findings was poor.{{image10-a:r-w:400}}Ordinary cases of diabetic macular oeda (DMO) warrant referral within 2–4 weeks of detection, as the situation is not urgent. However, in cases of significant oeda, the case needs referral, preferably the same or next day. A branch retinal vein occlusion (BRVO) has to be treated in well under six months if there is to be any chance of significant improvent.Any condition that risks a traction-caused macula-off sequel requires urgent attention, but if the macula is already ‘off’ and that situation is known to have existed for some time, referral is probably irrelevant. If the macula separation is very recent, again a referral is appropriate on the basis that, the sooner, the better. One sequel to macula-off is retinal cone cell apoptosis.In cases of diabetic retinopathy (DR), especially severe cases, the audience was advised to examine the whole eye, paying particular attention to the iris, which can show neovascularisation.DMO can occur at any stage of diabetes, while in later stages an epiretinal mbrane and possibly cataract can form with a reduction in VA. Epiretinal mbrane roval decreases the amount of anti-VEGF therapy needed for treatment. Cystoid macular oeda can be present if a yellowish dot is seen at the macula and an OCT is required to interpret the details.Referral periods in cases of central retinal vein occlusion (CRVO) with macular oeda depend on the features of the presentation starting at ‘within 2–4 weeks’. When neovascularisation is apparent, that time should be shortened to within one week. Additionally, a further shortening to 2–3 days was preferred when more than two clock hours are affected by neovascularisation. Symons said that if the intraocular pressure (IOP) is also elevated, the patient should have been seen “yesterday”.Referral within 2–4 weeks was recommended in another case involving lipid deposition at the edge of retinal cysts, and while not urgent, three months was stated to be too long a delay. The issue of patient follow-up arose and it was agreed that it is the referring practitioner’s responsibility to make every effort to ensure that patients attend appointments made to address their condition.All steps taken, especially in unsuccessful referrals, should be documented fully in case the issue becomes a medico-legal one instead. Cases of DMO warrant monitoring ‘forever’ and if anti-VEGF therapy is commenced, it too is probably ‘forever’ although possible on a PRN basis. The most anti-VEGF injections are given in the first 12 months and Symons revealed there is the possibility that such treatment modulates the course of the disease subsequently.Cases of RPE hyperpigmentation can result in a halo of pigment around the fovea and in OCT that can appear as hyper-reflective sub-retinal material. Collaborative care of retinal cases is possible if the referring optometrist has an OCT (6X6 mm scans were recommended) and they are able to interpret the images. Referral within one week was recommended if changes were detected.In cases of central serous retinopathy (CSR), monitoring by an optometrist equipped with an OCT was deed possible, however those not confident with such conditions should refer to an ophthalmologist instead. The key question of whether the overlying retina is intact can be answered by OCT, which can also determine the height of the lesions.If the condition does not improve over several observations within the initial six weeks, a referral is in order. Consideration of any pre-existing kidney condition is required if steroids are needed and the advice of a nephrologist may be sought by the ophthalmologist before commencing treatment. Unfortunately, CSR can recur frequently.Evolving technologiesUS-based keynote speaker Dr Jim Thimons spoke about the risk of endophthalmitis as a complication of cataract surgery and made recommendations for risk reduction.{{image5-a:r-w:400}}Data shows that when no prophylactic antibiotic is used the endophthalmitis risk is increased 5X. If there is vitreous loss during the procedure that risk rises to 17X, and if there is wound leakage subsequently the risk is 44X. Overall, the application of intracameral cefuroxime reduces the risk 3X.Thimons is a partner in a group practice that includes ophthalmologists and optometrists, and offers ftosecond laser cataract surgery (FLACS). He is a great supporter of FLACS, and described manual cataract surgery as “crude by comparison”.According to Thimons, the capsulorhexis is better centred, and the VA better, however, the latter assertion is not supported by the current literature which shows insignificant differences in most outcomes. He was particularly supportive of the 3-plane incision FLACS uses and the self-sealing qualities it imparts, but he did note that a large capsulorhexis can result in a myopic shift (and a small one in a hyperopic shift) if significant capsular fibrosis and shrinkage occurs. He also raised the issue of effective lens position because of its effect on final Rx.Perhaps more interesting was the detailing of a nascent technology, nanosecond laser-powered phacoulsification or photofragmentation – nanosecond laser cataract surgery (NLCS). A neodymium YAG laser with a wavelength of 1,064 nm is aimed at a small, oblique, reflecting titanium plate via optical fibres.Unlike ultrasonic phacoulsification, the extraneous energy applied to the lens beyond the immediate area, and by implication, the rest of the eye, is reduced to almost zero – ie, it is targeted rather than diffuse. It was claimed energy levels were reduced by >90%, while decreased endothelial cell damage and reduced capsule opacification were other reported benefits.Thimons then went on to recommend extended-focus prium intraocular lenses (IOLs), such as AMO’s TECNIS Symfony EDOF IOLs. These diffractive lenses offer smooth power progression to near, superior night vision, and correct partially some of the normal ocular aberrations, especially spherical and chromatic. The experience of his practice is that 66% of those implanted with Symfony IOLs do not use spectacles at any time.He urged caution with patients who are highly myopic and those who have had refractive surgery previously – especially oblate ablations, those with small or decentred ablation zones, and those who have had highly hyperopic ablation performed. Thimons was also supportive of the Ocular Response Analyser device, which attaches to an operating microscope, and offers intraoperative wavefront aberrometry and intraoperative Rx suggestions (sph, cyl, axis).The routine use of OCT before all cataract surgeries was also recommended as some 13% of all patients believed to be ‘normal’ actually had some issue warranting pre-operation treatment or special consideration. Furthermore, cases whose macular thickness was >230 microns have been shown to have worse surgical outcomes. He also recommended that any tear film and ocular surface issues be resolved before any surgery.Cystoid macular oeda (CMO) was given as a possible post-surgical complication and if the capsule is broken, explantation of the IOL is a possibility. Meanwhile, pupil decentration was another possible pre and post-surgical issue, especially in cases of multifocal IOL implantation. A possible solution is an iridoplasty (using four laser ‘dots’) to recentre the pupil relative to the IOL.Thimons then changed direction and detailed surgical presbyopic options located within the cornea, namely the Kamra and Raindrop devices. While the Kamra implant is placed under a LASIK flap or corneal pocket and is intended as a monocular solution, the Raindrop can be implanted binocularly.The Kamra works best in those with distance Rxs of plano to –0.50 DSph who do not have dry eye or other ocular surface probls. Previous refractive surgery can complicate matters. The cosmesis of the disc is not great but they work “better than expected and provide good ‘room’ vision” according to the presenter. Surprisingly, most ophthalmic instruments can still be used successfully on patients with a Kamra implanted.The Raindrop is a small, hydrogel (80% water), symmetrical, aspheric inlay that requires careful placent to be successful. It is compatible with those rendered pseudophakic previously, and it too is placed centrally under a ftosecond laser corneal flap. Only approved in the US in 2016, reports suggest that while it offers a five-line improvent at near, it may come at the cost of a one-line loss at distance. Cosmetically, it is invisible for all practical purposes.The MIGS answers to glaucoma (iStent, Cypass, etc.) were also detailed and unlike some early version ploying metals, the more recent versions are MRI and TSA-scanner proof. A more recent product, the Allergan XEN Gel stent, connects the anterior chamber to the sub-conjunctival space and has been shown to offer a 40% reduction in IOP after three years during clinical trials.
KEYNOTE SPEAKERS |
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 Jim Thimons |
 Daryl Guest |
 Andrew Symons |
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Managing diabetic retinopathy (Type 2 Diabetes)Medical retina specialist Dr Simon Chen opened his session by suggesting that practitioners ask diabetics what their HbA1c (glycated haoglobin) levels are. From his experience, the ability and confidence, or in some cases their inability, to answer the question is telling. It is indicative of their knowledge and understanding, compliance, control, etc. of their own condition.HbA1c levels help predict the rate of progress of the disease and are suggestive of the risk of developing diabetes-related complications such as diabetic retinopathy (DR) and their likely progress rate. They are also used to determine the frequency of after-care monitoring during serial reviews, as it is an analogue of disease progress. The original question also opens opportunities to educate, and alerts the patient to the importance of diabetic control.Further, if that question is asked at every encounter with their health practitioner, the patient starts to pay more attention to the issue in anticipation of being confronted by the question repeatedly.Paradoxically, patients with rapid improvents in their diabetes require more frequent monitoring, as 22% of such cases had a three-step reversible progression of DR. Usually, it is not until some 18 months later that a beneficial reversal occurs, provided tight control is maintained in the interim.Rapid decreases in glucose levels result in decreased retinal perfusion and retinal ischaia. Episodic hypoglycaia can also increase VEGF production and neovascularisation can ensue. The longer diabetes has been present, the more likely the patient is to show the effects of the disease and the more severe the disease, the greater the changes induced are likely to be.Diabetes in pregnancy might be gestational and therefore likely to prove to be transient, or pre-existing. The higher progesterone levels present can increase VEGF production. Chen advised prospective diabetic mothers to seek a review of their status before conception. Once pregnant, careful review during at least the first trimester was advised, because if disease control is poor during that period, the HbA1c levels can decline rapidly. Additionally, the risk of hypertension is also increased.Fortunately, many pregnancy-related changes reverse postpartum. Fluorescein angiography is rarely performed in pregnancy but what little data is available suggests it is relatively safe. It is probable that as OCTA technology matures, it will fill those monitoring needs adequately, providing the retinal periphery is not of special interest. In probl cases, anti-VEGF is not especially effective but it may slow the angiogenesis process beneficially.For diabetics, it is prudent to have the disease under optimised control before cataract surgery is contplated as it can progress DR rapidly. One Australian study by Hong et al. (2009) showed that the combination of DR and phacoulsification can double the progress rate of DR at the 12-month mark.Chen advised practitioners to involve the patient’s GP and endocrinologist in the treating-practitioner loop, meaning at least four health professionals are on each case. The inclusion or suggestion of including fenofibrate in the treatment regimen was also advised. During his presentation, Chen even provided a diplomatic covering letter to suggest just that, knowing that some in the audience would be reticent to suggest such a step to a medical practitioner.The development of an epiretinal mbrane increases the risk of developing post-operative macular oeda. In cases of DR, multifocal IOLs were not advised as vision is already compromised without the associated compromises introduced by MF IOLs. Meanwhile, monovision should be avoided if DMO is present because VA might then be reduced in both eyes. Post-operatively, prolonged use of topical steroids and NSAIDs is usually accompanied by closer patient monitoring.Diabetics run a 17% greater risk of developing cystoid macular oeda, especially if DR is present and diabetics already have a compromised blood-retina barrier that surgery is likely to make worse. However, a new topical NSAID, nepafenac 0.3%, permeates the cornea and sclera, and decreases the risk of macular oeda while also giving a slight improvent in VA.Chen then moved to what he termed the ‘featureless’ retina that can be a result of severe retinal ischaia. The signs were described as subtle, but a careful anterior slit-lamp examination will reveal vessel attenuation and sheathing.Retinal ischaia enhances VEGF production, giving a broad neovascularisation consisting of poor quality new vessels that can lead to neovascular glaucoma. Such cases can end in enucleation.Chen pressed the message that the peripheral must be assessed regularly in all diabetics as 10% have mild retinopathy changes in the posterior pole that are more severe in the periphery. Sheathing of peripheral blood vessels is indicative of there being no significant blood flow within.The presence of intraretinal micro-abnormalities should be a trigger to ask the patient’s GP to introduce fenofibrate to the medication the patient is on, as its inclusion will decrease the rate of progression of the existing DR. Importantly, at this time, the effect of these treatments in Type 1 diabetics is unknown.According to Chen, the combination of simvastatin and fenofibrate can reduce DR by 40%. Fenofibrate usage can reduce the need for laser surgery by 31% and is well-tolerated generally, however, side-effects can include nausea and diarrhoea among others.Addressing the usage of the Optos wide-field instrument and OCT, Chen estimated that between 2% and 20% of all fundus photographs are ‘ungradable’ and therefore not especially useful clinically due to cataracts, lid squeezing by apprehensive patients, operator error, etc.The tporal retina is more likely to be the probl retinal area and the Optos performs better than fundus cameras, especially in cases of vitreous haorrhages. Asteroid hyalitis, a difficult imaging situation even in mild cases, is also better served with an Optos. An OCT also fares well in that condition and surprisingly, so too does fluorescein angiography.More reading: Southern Regional Congress 2017 Part 2
