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Dr Cameron Hudson (professional services manager for CIBA Vision UK introduced each day of the roadshow with a lecture reminding all delegates of their influence upon patient correction at each end of the age spectrum.
Fitting early
Children may be safely fitted with contact lenses and, as The Adolescent and Child Health Initiative to Encourage Vision Empowerment study by Jeffrey Walline had shown, there is no evidence of a myopic progression if children as young as eight are fitted with soft lenses. In fact, many recent studies have suggested that far from being problematic, there is better compliance among younger children and a lower incidence of sterile infiltrative events. When dealing with adults it might be useful to bear in mind the recent case whereby a lawyer had tried to sue his eye care practitioner for keeping him in conventional hydrogels rather than suggest silicone hydrogels with their better oxygen profile (despite there being no clinical indication of a negative impact with this patient of the former).
Dr Hudson explained how the Association of Optometrists now talks about a 'duty to inform' applying, not just to the information passed to a GP upon referral directly to hospital, but to the requirement of a practitioner to inform the patient about products with clinical advantages in certain situations. The real life case settled out of court, but it would be wise to be aware of this interesting case.
Presbyopic fitting with contact lenses, he continued, presented fewer challenges than used to be the case as modern designs give better visual performance. Recent studies have shown how they are preferred to monovision by the majority of wearers. It was also worth thinking about the way they are introduced to a patient. Suddenly saying 'have you thought about contact lenses?' might be misconstrued as a negative statement on someone's spectacles. However, many patients were still unaware of the potential for presbyopic lenses and this was something eye care practitioners (ECPs) need to address.
Myopia
Bill Harvey (Optician) then gave a review of the latest research into myopic progression and its possible control. He suggested that the dual influence of genetics and environment was influential in the increasing prevalence of the refractive state and offered sobering figures from around the world. In the Far East there is now a 90 per cent or higher prevalence of myopia of 0.75DS or more in school-age children and this has an economic and a social impact.
It was also worth considering the potential for pathological change with progressive myopia and Harvey showed some cases from the Visual Impairment clinic at City University where increasing myopia had led to macular hole, myopic atrophy, subfoveal haemorrhage and retinal detachment. There was also an established association between myopia of greater than -2.00DS and primary open-angle glaucoma. All this means that interest in any attempt to influence or slow progression has been high.
Animal models have suggested how near stimuli and the nature of those stimuli have some impact. Recent research proposed by workers such as Earl Smith III had shown how keeping a foveal focus while projecting an off-axis peripheral defocus outside the retina (a hyperopic shell) seemed to play a role in promoting axial length increase.
Workers such as Donald Mutti have suggested that initial anterior changes such as to the ciliary body and thinning lens (possibly primarily genetically induced) might trigger this secondary elongation of the posterior chamber which is driven by this off-axis defocus. Lenses designed to bring this peripheral focus forward onto the retina but still maintain an on-axis focus have been developed, most notably by Dr John Philips based in New Zealand. His MyoVision lenses are available as spectacle lenses (patented by Zeiss) and a silicone hydrogel (AirOptix material lens, yet to be named, patented by CIBA) and initial human trials have shown some significant reduction in myopic progression when the dual focus lenses have been prescribed (see the BCLA review in August and our myopia CET strand in the autumn for much more on this).
Compliance and care
Dr Kathy Dumbleton (Waterloo) offered further evidence on the importance of compliance as a way to reduce adverse responses. This was followed by Sarah Morgan (Manchester University) who used video footage of a young patient whose life had been transformed by a move from spectacles into contact lenses - a powerful message well delivered.
The finale was a real-life punch up with Harvey and Morgan donning boxing gear to slug it out in a debate about the pros and cons of contact lens wear. Luckily for the organisers, the motion that contact lenses should be mentioned to all at the first appointment was carried by a majority that increased after the debate! ?
