Back for its eighth year, the Specsavers Clinical Conference delivered two days of presentations to optometrists, locums and optometry students. In the first of a two-part series, Lewis Williams reports on the event.
As has become the norm, the eighth Specsavers Clinical Conference (SCC8) was held at Melbourne’s Convention & Exhibition Centre on the 7th and 8th of September 2019.
Around 750 delegates attended both days alongside a total of 25 exhibitors, which included schools of optometry, eye health organisations, and industry suppliers.
The opening address was delivered by Dr Ben Ashby, Specsavers director of optometry, who acknowledged that delegates were a mix of both Specsavers and non-Specsavers optometrists, as well as students.
He noted that all Specsavers stores have commissioned OCTs, marking the end of the national rollout that commenced in 2018. The project has been accompanied by ophthalmologist-led training programmes for relevant staff. Glaucoma referrals and detection rates have approximately doubled in stores equipped with OCT, and a diabetic screening programme has also been instigated.
With the number of people attending a Specsavers store annually now in the millions, the potential influence of efficacious screening programmes is obvious.
Optometric management of paediatric conditions
Sydney-based paediatric ophthalmologist Dr Caroline Catt used a case-based approach to cover several eye conditions that might present to an optometrist.
Her first case was a 13-year-old female with a left hypertropia that was exacerbated by a left head tilt and could be compensated for by a right head tilt. The girl was also autistic, suffered from ADHD, and had recently endured a dog bite. Vision was normal in both eyes, but a decreased sensation over the left brow was reported.
Excyclotorsion was observed during a fundus examination. The problem developed after the facial injury, which resulted in a significant laceration. A left superior oblique (LSO) muscle palsy was diagnosed and the condition was described as an uncommon cause of a superior oblique palsy. That is, trauma to the supra-nasal orbit. Surgical management was required.
The second case was that of a 7-year-old female who reported 3 months of difficulty reading and seeing the blackboard at school. Reading glasses produced no improvement. She also reported a virus-induced wheeze requiring an occasional dose of Ventolin.
Visual Acuity (VA) was found to be about 6/15 OU. Importantly, a pinhole did not improve the VA, suggesting a non-refractive aetiology of the vision problem. Stereopsis was good and only a small exophoria was found. Retinoscopy under cycloplegia was normal for the patient’s age (+1.25 and +1.50 DSph).
Catt stated that several terms were used to describe non-organic vision loss, but the firming favourite is Vision Conversion Disorders (VCDs) – disorders that are subconscious and certainly not voluntary.
The first step is counselling the parents and the patient, usually separately, about the condition and offering a likely timeframe for any expected improvements.
The characteristics of VCDs were given as:
- Symptoms do not fit any known ophthalmic disease
- There are not explained by organic disease
- Usually, diagnosis by exclusion is required
- Assign the condition to ‘unknown cause’ if necessary
- Age range is generally 6 to 16 years
- If the patient is more than 10-years-old, they are 3x more likely to be female
- Most patients seem neither concerned nor inconvenienced by an apparently severe vision loss.
Catt cautioned the audience about the possibility that a VCD could be superimposed on an organic disease. Presentations can include: blurred vision, visual field defects, and distorted colour vision. The defects are usually bilateral.
Possible stressors include: family disharmony, school-sourced stress, change of ‘habitat’, bullying (increasingly common in the social-media era), a recent vision test, sibling rivalry, and friends/classmates getting glasses recently. Often coaxing the patient can result in vision improvements but equally, differences can be found from day-to-day.
Sometimes, ‘tricky’ retinoscopic or tricky fixation findings will also be noted. When reading, the tone can be monotonous and the delivery/recital slow, often with the sound tapering off at the end. Alternatively, a sing-song style of recitation can be adopted.
Catt advised that the parents be spoken to first and together with the patient later. A clear aim is to identify the stressors and referral to a psychologist might be required in refractory cases.
In the same vein, case 3 was of a 14-year-old female with several years of reduced vision (6/24) but only –0.50 DSph to explain the decrease. A cycloplegic refraction, electrophysiology, and OCT revealed nothing further.
Tellingly, visual fields were unreliable (VFs are significantly more difficult to be ‘consistent’ with) but were suggestive of a bi-nasal hemianopia. Further investigation revealed that the onset coincided with bullying at a new school. Fortuitously, the patient shared her parent’s enthusiasm for motorcycles, and her desire for a motorcycle licence was used to resolve the issue.
Case 4 was a little more serious and featured an 8-year-old female patient who had indistinct optic disc margins, intermittent headaches, and behavioural and schooling difficulties.
VA and a lumbar puncture proved to be normal. Idiopathic intracranial hypertension was diagnosed. Papilloedema and intermittent headaches are known to accompany the condition. The condition is rare (0.6 cases per 100,000 children) and is more likely to affect females and the obese.
Interestingly, the patient did not respond to the use or discontinuation of acetazolamide therapy, and the disc appearance did not change over a 3-year period. Treatment was stopped as a result. It was also noted that intracranial pressure can be normal and the disc still be elevated.
Another case was that of a 9-year-old female with acute leukaemia since the age of 2 and the development of a strabismus at 3. The steroid therapy resulted in posterior, sub-capsular cataracts bilaterally. She reported a large, bilateral esotropia that lasted 11 hours following a bump to the head.
A week later, the condition returned and lasted 24 hours. Later, an MRI revealed a lesion in her cerebellum. Vision returned to normal but a miosis and an esophoria were found at near. Furthermore, a slight pupil enlargement was noted when the eyes resumed straight-ahead fixation. A spasm of accommodation/convergence was diagnosed and 1% atropine twice a day was prescribed for 3 days, as was a pair of bifocals (+2.00 DSph OU, Add +3.00).
Surprisingly, 3 weeks later she returned with an alternating esotropia that eventually subsided, leaving her with a small amount of esophoria. Further investigation identified a misunderstanding on the part of the patient whereby she understood, erroneously, that her childhood cancer had returned and triggered the whole episode.
The final case was that of a 5-year-old female who was playing at being cross-eyed with a friend. A large comitant, left esotropia and 6/9 VA OU resulted. Retinoscopy was normal for the age (+1.50 DSph OU). Trial glasses and an MRI were ordered. Sudden onset comitant esotropias can be a result of an artificial interruption to fusion and be of the Bielschowsky-type in ametropes of up to 5 D myopia, or a Franchetti-type that has no apparent cause but often follows a bout of illness.
Glaucoma: Diagnosis and management
Western Australian ophthalmologist Dr Dru Daniels undertook the well-trodden topic of glaucoma. It never fails to engage audiences since the more that is learned, the more it is realised just how mysterious certain aspects of the condition can be.
Glaucoma affects about 1.3% (range 1 – 1.5%) of the population, but far too many remain unaware until symptoms become too significant to ignore. Unfortunately, by that stage much irreparable damage has already been sustained, leading to less than ideal outcomes.
Of a cohort that exhibit glaucoma-related signs and/or symptoms, 18% are likely to be considered glaucoma suspects, 53% will be placed on a review path, and 29% will be entered into a collaborative care regimen. While intraocular pressure (IOP) is still important, the three main steps in glaucoma investigation remain an examination of the optic nerve head (ONH), a dilated fundus examination (DFE), and a visual field (VF) assessment.
IOP is highest when the body is supine and asleep. Daniels recommended that delegates not be afraid to dilate eyes for fear of precipitating an angle-closure event because in his experience it has never happened in over 100,000 dilations. Although the risk of angle-closure is not zero, dilation is essential if a good view of the fundus and the ONH is to be had. Generally, a VF assessment simply confirms the function aspects that are a sequel to the anatomical posterior pole findings.
Glaucoma remains the number two cause of preventable blindness worldwide. In the very old, a decision to treat or not comes down to the question: Will glaucoma outlast the patient? Australian data suggests there are about 400,000 glaucoma sufferers and a further 400,000 suspects with elevated IOP. Early detection is important because late presenters generally do badly even when treatment is commenced. Optic disc features, such as cupping and disc rims, that are not the normal salmon pink should always trigger suspicion.
Importantly, does the VF match the ONH appearance? VF assessment is more appropriate to confirm progression of the disease, rather than diagnosis, because up to 50% of optic nerve loss can occur before VF defects become apparent.
Usefully, modern VF devices offer data that gives an idea of how reliable findings are. Generally, OCT has overtaken the role previously occupied by the Heidelberg HRT. The more recent OCT-A technology allows the perfusion of the ONH and optic disc capillaries to be assessed. That is significant because glaucoma generally decreases ONH perfusion.
There are some conditions that can masquerade as glaucoma, such as a neuropathy resulting from compression of the optic nerve. While MRI can disclose such a situation, its yield rate is generally low. Pituitary tumours can result in VF defects.
Other possible masquerades include ischaemic optic neuropathy, hereditary issues, and nutritional deficiencies. Even if it is not glaucoma there is the possibility that lowering IOP might still be useful. In one US National Institutes of Health study, a glaucoma misdiagnosis rate of 25% was reported.
Ocular hypertension was reported to be common, and greater care was required when there is a family history, the patient is myopic, has thin corneas, or is of advanced age.
If IOP is >30 mm Hg, a good first line treatment is selective laser trabeculoplasty (SLT), especially if the patient is young. However, SLT is not regarded as primary glaucoma therapy. Rather, it is a temporary step.
Daniels gave the standard glaucoma treatment options as:
- Xalatan (latanoprost – a prostaglandin analogue) as a first line of defence
- Timolol (a beta-blocker) – especially useful if dry eye or blepharitis is present as it is better tolerated. However, it is unsuited to those suffering from asthma or heart disease and is known to have the potential to cause depression, respiratory difficulties, and asthma.
While compliance is an evergreen problem, it has been shown that once more than one medication is prescribed compliance plummets.
Alphagan (brimonidine tartrate) eye drops can result in up to 40% of users experiencing red, dry eyes. When eye drops prove to be unsuitable, the alternatives include minimally invasive glaucoma surgery (MIGS), a trabeculectomy, or some other surgical approach.
Glaucoma severity varies widely. Up to 52% of case are classified as mild, 25% as moderate, 13% advanced or severe, and 10% refractory. Once control was well established, Daniels’ recommendation was for the patient to be seen ophthalmologically every 2 years and optometrically in the odd years. He emphasised that glaucoma was a lifelong condition that involved an accelerated loss of optic nerve function.
Cataract surgery is useful in glaucoma management as it is known to lower IOP for at least 2 years. This can be longer in hyperopes, especially if greater than 2 DSph, but is less beneficial in myopes. The insertion of a MIGS device is also possible in conjunction with cataract surgery. A gonioscopic examination is critical in all patients. He also advised against the use of multifocal (MF) IOLs in any case, except those that are mild and non-progressive.
MIGS devices allowed earlier intervention with the potential to reduce the disease’s morbidity and the burden of medications. Although the Cypass Micro-Stent has been withdrawn from the market due to detectable corneal endothelial cell loss, Daniels expressed the opinion that it was probably not a real issue.
As a comment on the cost of MIGS devices he estimated that 1 kg of I-Stents was worth $1 trillion. Overall, he estimated that MIGS lowered IOP by 23-43% after settling, and medication usage was reduced by 46-67%. He also called out the industry for having the tendency to overstate the performance of MIGS devices.
Other treatments touched on in his presentation include Ellex’s iTrack laser re-establishment of the trabecular meshwork for 360 °, trabeculectomy, and Baerveldt or Ahmed tubes/valves. He also noted that pigmented races do not do as well with conjunctiva-based surgical solutions.
He summarised his take on glaucoma as a case of giving the correct diagnosis and stratifying the risk guided by the following factors:
- ONH condition
- NTG vs. high IOP (NTG remains a difficult issue)
- Pigmented race?
- Tailor the management strategy
- Co-management with an optometrist
Despite advances made in our understanding of the disease, glaucoma therapy remains IOP-lowering centric and fading levels of compliance remain a problem. Despite advances in instrumentation, the Goldmann applanation tonometer (1950) remains the gold standard.
Helping patients avoid laser eye surgeons
Sydney ophthalmologist and refractive, corneal, and cataract surgeon Associate Professor Colin Chan undertook this seemingly contrary topic to assist the audience to refer only the most necessary for laser eye surgery.
He estimated that annually there about 250,000 CL fits undertaken in Australia and about 25% of all microbial keratitis (MK) were CL-related. He estimated further that about 47.5% of contact lens-induced papillary conjunctivitis (CLPC) cases were also CL-related, as was up to 50% of dry eye (DE) cases. Other noteworthy conditions included: Acanthamoeba keratitis (AK) – about 4-8 people affected annually, 40,000 MK annually, CLPC/GPC 58,000 annually, and DE 125,000 annually.
He finds that refractive surgery candidates are motivated by dissatisfaction or unhappiness with either their spectacles or CLs, and sometimes both.
Those unsuited to refractive surgery include:
- Forme fruste keratoconus (FFKC)
- DE cases
- Chronic blepharitis sufferers
- Epithelial basement membrane dystrophy (EBMD)
- CL-related infiltrative keratitis/CLPC(GPC)
- Those with certain personality characteristics
He reported that fully 66% of refractive surgery candidates suffered from DE, a figure that probably goes a long way to explaining the incidence of DE immediately after refractive surgery. Quoting the literature, he reported that 10-50% of CL wearers had discontinued wear within 3 years of commencing. Discomfort is the main issue.
In the general population, 12% of those over 50 years of age report DE. About 75% of LASIK candidates have tried CLs, with discomfort and DE the major barrier to wearer success.
The DEWSII report tends to confirm Chan’s claim that managing DE is something of an art and the division of the disease into four stages was a welcome development.
Initial treatment mainstays are still dietary modification, ocular lubricants, and lid hygiene. However, compliance remains a significant problem and drops off fairly rapidly after commencement of a treatment regimen. He also noted that a PRN regimen was not useful, and the prescribed treatments should be applied routinely regardless of the patient’s subjective impressions.
Special care is required when DE and possible laser treatments were contemplated, especially if the patient is female, of Asian descent, has MGD, has a connective tissue disorder, Sjögren’s Syndrome, Fuch’s Dystrophy (especially if Caucasian female) or an androgen deficiency (menopause). Laser surgery or CL wear can only be considered if, and when, the magnitude of any DE problem is lessened by suitable treatment.
Should blepharitis be a cause of CL intolerance, it must be treated successfully before continuation of CL wear is contemplated. He estimated that about 70% of old people had DE and figures in the general population could be as high as 37-47%. The adverse effects of blepharokeratitis are worse than blepharitis.
Compliance with instructions to use lid scrubs has been shown to fall to 50% after just one month. If CL-related infiltrative keratitis (CLIK) is detected, it too must be treated before continuing with CL wear or progressing to laser surgery. If CLPC/GPC is present, an anti-histamine and a mast-cell stabiliser are required. If a particular mast-cell stabiliser does not work, Chan suggested trying an alternative before discontinuing.
In cases of unhappy MF CL wearers, he suggested that signs of map dot dystrophy be sought using sodium fluorescein. About 43% of older patients exhibit the problem.
Chan noted that high myopes tend to get cataracts earlier (as early as 35 years of age). Vitrectomies for macular holes, for example, can also bring forward cataractous changes. When corneal conditions are present, have been present, or are under treatment currently, he suggested that monofocal IOLs be used rather than more complex options in the interest of better vision in the longer-term.
If monovision is considered an IOL option, he suggested strongly that an analogous CL monovision trial precede any final decision.
For particularly pedantic patients, especially those with high vision demands, he warned the audience to steer clear of MF spectacles, CLs, or IOLs. He gave the following as characteristics to be on the lookout for:
- Compulsive checking of vision and differences between eyes
- Obviously competent and confident individuals
- Those striving for achievement constantly