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Wednesday / August 17.
HomemieventsOphthalmology Updates – Clinical Pearls

Ophthalmology Updates – Clinical Pearls

The second ever Ophthalmology Updates conference was held from 29–30 July 2017 at the Westin Hotel, Sydney. Each of the 12 speakers presented one ‘common’ topic and one ‘cutting edge’ topic from their subspecialty, followed by case presentations as illustrations.

Topics presented at Ophthalmology Updates were well chosen, and each talk was rich in clinical application and relevance. The segments were just the right length to keep delegates interested the whole way through. Here are some clinical pearls I picked up from the weekend.

A/Prof. Raf Ghabrial was the first speaker. He explained that the fluorescein dye disappearing test is the best way to assess epiphora, because an active test, like probing and syringing, cannot detect a functionally obstructed duct. In complete nasolacrimal duct obstruction, endonasal dacryocystorhinostomy (DCR) is now almost as successful as external DCR.

Thyroid eye disease (TED) is often managed sub optimally, hence the European Group on Graves’ Orbitopathy (EUGOGO) clinical activity score should be used in all patients. While orbital decompression is necessary for sight threatening orbitopathy, people with mild TED cases are often selenium deficient – so start prescribing six Brazil nuts a day!

CORNEA

Prof. Stephanie Watson said dry eyes can be as debilitating as angina. Ocular Surface Disease Index (OSDI) or SPEED questionnaires can help us to assess this. Look out for modifiable causes such as lagophthalmos, rosacea, superior limbic keratoconjunctivitis (SLK), and sleep apnoea; and drugs like systemic antihistamines and beta blockers. Unfortunately, topical Cyclosporine only has a 16 per cent success rate – no wonder so many discontinue this medication.

I have already made changes to my clinical practice because of what I learnt from the conference

Discussion about collagen cross linking (CXL) followed. It is most commonly used for young adults with documented progression of their keratoconus. In older adults and young children, the indications are less clear. The topography of the cornea takes a long time to settle down after CXL. The evidence for use of CXL in microbial keratitis is still unclear.

Uveitis

Prof. Peter McCluskey said that a uveitic cataract should be operated on only after the eye has been stable for at least three months. Consider peri-operative steroid for all uveitis patients except for Fuchs and quiescent anterior uveitis. Ozurdex and intravitreal Triamcinolone can be used intraoperatively. It’s best to use a non-toric, monofocal acrylic IOL. Tissue plasminogen activator (tPA) injection can clear post-operative fibrin in the anterior chamber within 20-30 minutes. Usually, the prognosis after cataract surgery is very good.

The discussion moved to ocular toxoplasmosis, which is usually an acquired condition, not congenital as was previously thought. Found in young and otherwise well patients, it can cause retinitis, vasculitis or moderate pan uveitis. Only those with severe uveitis, lesions near important sites, multifocal lesions or immunocompromise would require treatment. Pyrimethamine, sulfadiazine and clindamycin are used to treat the infection. Oral steroid treats the inflammation. Bactrim DS, two to three times per week, is a good prophylaxis which can be given for three to five years.

Vitreoretinal

A/Prof. Andrew Chang advocated early vitrectomy for vitreous haemorrhages. Advances in technology mean that vitrectomy achieves better results than previously reported. It can be combined with laser and intravitreal anti VEGF or triamcinolone. He also warned that acute peripheral vascular disease (PVD), with no breaks in the initial examination, still has a 2 per cent chance of developing tears in the following weeks, and a retinal tear has a 5-15 per cent risk of developing tears in the future. Hence, follow up these patients.

Intracameral cefazolin, cefuroxamine and moxifloxacin are effective prophylaxis for post cataract endophthalmitis. Topical antibiotics, antibiotic in the irrigating solution and intracameral vancomycin are not. For intravitreal injection endophthalmitis, streptococcus from saliva is a common organism. This has a poor prognosis hence all staff, including those who prepare the field, should wear a mask to reduce contamination. If endophthalmitis occurs, tap and inject immediately before referring the patient on. The tendency is also to move towards early vitrectomy here.

Ocular Oncology

A/Prof. Max Conway warned that suspicious choroidal naevi, large iris naevi, and Primary acquired melanosis (PAM) can develop into melanoma. However, when discovered and treated promptly, the prognosis is excellent. Follow up suspicious lesions every three to six months, especially if there is documented growth. Useful tests are A and B scan ultrasound looking for echolucency, optical coherence tomography for subretinal fluid without thinning of the retina, and autofluorescence for lipofuscin.

Conjunctival SCC and melanoma are sometimes hard to distinguish, especially in amelanotic melanoma. Excisional biopsy, using the ‘non-touch’ technique, is the mainstay of diagnosis and treatment and adjuvant cryotherapy can be done sequentially if it is not initially available. Cytology alone is inadequate. Targeted therapy for conjunctival melanoma is available, so molecular testing is now done routinely. It’s possible that immunotherapy will be the main treatment for melanoma in the future.

Electrophysiology

A/Prof. John Grigg was the last speaker on Saturday, and he advised all that we should know (but have probably forgotten) about electrophysiology. He reminded us that there are many tests, and some combinations can take up to two hours to perform, so a good clinical history is imperative. Visual function, medication, family history and relevant systemic problems should be noted on the referral form.

The rest of the evening was pleasantly employed by an interesting candle-lit tour of Elizabeth Bay house, which was the finest privately owned house in Australia when it was built. The dinner that followed was at a lovely restaurant at Barangaroo.

Cataract Surgery

Sunday started bright and early at 8.30am sharp. A/Prof. Geoffrey Painter gave a comprehensive summary and practical tips about dealing with zonular instability. He confirmed that of the many different IOL formulae available, Prof. Graham Barrett’s is the best overall. Fudge factors for very long eyes and how to plan the other eye after a refractive surprise were discussed. And he recommended the ASCRS IOL calculator as it achieves very good results in eyes post-refractive surgery.

Neuroophthalmology

A/Prof. Clare Fraser reminded us that the only sine qua non of giant cell arteritis is the age of >50 – even a normal erythrocyte sedimentation rate doesn’t rule it out. The home-grown ‘chewing gum test’ is a simple way to look for jaw claudication. The good news is that the histology remains positive no matter how long the patient has been on steroid, so a biopsy should be done, and steroid should be started if we suspect giant cell arteritis. Aspirin and a proton pump inhibitor should also be started concomitantly.

Atypical optic neuritis does not fit the profile of patients in the Optic Neuritis Treatment Trial. In this subgroup, the population is >30 years old, African or Asian, and there is bilateral involvement (can be sequential), with progression and pain that continue for >2 weeks. They require steroid. Also check for NMO-IgG and anti-MOG antibodies. Consider vitamin D supplementation if the baseline level is low in your optic neuritis patients.

Paediatrics

Dr. Michael Jones discussed the delicate diagnosis of functional visual loss in children. He explained these kids are not intentionally feigning illness, and internal conflict at home or school can precipitate it. The diagnosis must be proven – it is not a diagnosis of exclusion. A thorough examination rather than tests is the key and once diagnosed, it should be discussed and explained openly and sensitively. Give kids a chance to recover without embarrassment.

The different modalities of treatment of retinoblastoma was discussed next. Dr. Jones reminded us that the preservation of life trumps the preservation of eye, which trumps the preservation of vision. Each type of treatment must be evaluated in this light.

Medical Retina

Dr. Jennifer Arnold discussed hydroxychloroquine screening – if you see bull’s eye maculopathy, it’s too late! The aim is to detect pre-RPE loss. This is quite prevalent (7.5 per cent), and the ‘safe’ dose has been changed to <5mg/kg/day of real (previously ‘ideal’) weight. The best test is to use HVF 10-2 white target, but use 24-2 in Asians. Field changes occur earliest in all tests. The risk of maculopathy increases every year, so after five years, screen yearly.

Chronic central serous retinopathy is often difficult to distinguish from age-related macular degeneration. It is a pachychoroid abnormality (>395 microns). This can be detected by using enhanced depth imaging (EDI)-OCT with the Cirrus. Autofluorescence can confirm chronic changes such as gravitational tracts. It is difficult to treat, and the most promising therapy is PDT with Visudyne. Mineralocorticoid receptor blockade with Eplerenone may also have a role.

Glaucoma

A/Prof. Andrew White explored angle closure glaucoma. In Asian eyes, we should consider the diagnosis of plateau iris. Here peripheral iridoplasty is effective in eliminating residual angle closure in patent iridotomies. He also highlighted the EAGLE study, which shows that clear lens extraction achieves better results than peripheral iridotomy for angle closure patients. That might lead to interesting consequences!

He also gave a quick run through of the available modalities for glaucoma imaging. The bottom line is that the good old fundus photograph is still the best record keeper, and the best way to visualise the angle is still gonioscopy. “No modality is better than a well-trained observer at present,” he stated.

Medicolegal

The day ended with Dr. Paul Beaumont discussing fitness to drive assessment. In our desire to advocate for our patients, we must consider the safety of the public. I found the most helpful discussion was about interpreting the Estermann test for licencing purposes.

A/Prof. Adrian Fung should be congratulated for organising such a well-run conference. It was enjoyable, relevant and interesting. I have already made changes to my clinical practice because of what I learnt from the conference. It’s sure to grow from strength to strength!

Dr. Michelle Gajus LTCL, BSc(Med), MBBS (Hons), FRANZCO trained in ophthalmology at the Royal Victorian Eye and Ear Hospital (RVEEH) in Melbourne. She practises with Illawarra Ophthalmology in NSW and works exclusively in the Illawarra region.