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Peripheral light, particularly from the extreme temporal area, so not usually influenced by spectacle wear, can pass via the anterior eye to be focused at the opposite side exactly where one tends to find pterygial growth and cortical lens opacities, evidence in itself of the involvement of light exposure in the progression of these diseases.
The damage that short wavelength radiation causes to surface tissues can be shown quite dramatically by a recently developed photographic technique. Ocular UV fluorescence photography highlights preclinical cell damage and an image of the interpalpebral region of TVCI education director Jane Veys, who under normal examination has normal clear and flat interpalpebral bulbar conjunctiva was projected on screen and seen to clearly show fluorescence at 3 and 9 o'clock to match the cellular damage related to light exposure. Professor Coroneo added that understanding how light triggers the stem cell changes that drive degenerative change will help to explain inflammatory disease mechanisms.
Adequate protection against ultraviolet exposure is important, he went on, and full corneal coverage as with a UV blocking contact lens, or improved protection via a wraparound spectacle is important. Ironically, complete avoidance of ultraviolet light has resulted in vitamin D deficiency, the vitamin requiring sunlight for its synthesis before assuming its role in bone metabolism. A lack of sunlight and vitamin D in the diet has led to a resurgence of 'old' diseases such as rickets. There is also evidence that multiple sclerosis may be linked to inadequate vitamin D in the diet.
Multifocals for children
Associate Professor Jeffrey Walline is well known for his association with major studies in paediatric eye care. He has recently looked at the potential for contact lens use in controlling myopia. Influencing the peripheral focal shell may slow myopic progression and, Professor Walline explained, orthokeratology and soft bifocal lenses do just that by focusing light in front of the retina and thereby slowing growth, in some studies as much as 40 to 50 per cent.
He stated that, while atropine therapy has proved successful, it is not recommended as there are significant side-effects and, once a treatment has ceased, the effects are reversible. Contact lenses with the smallest optic zone and the highest tolerated add might be the best approach.
A vote by the delegates suggested that the vast majority might in future consider multifocal contact lenses as a means to slow myopia. In a lively panel discussion that ensued, Dr Phil Morgan questioned whether many parents would consider having their children fitted with such lenses to merely slow myopia which would ultimately still require correction.
One person in the audience admitted to already using orthokeratology as a 'myopia therapy' while the majority, it appeared, felt more comfortable waiting for more evidence of successfully reduced error before wholeheartedly supporting myopia control.
Professor Lyndon Jones offered his excellent review of modern care systems, following from his lecture at the College of Optometrists conference last year, which was then developed by Dr Morgan who outlined the importance of getting the contact lens material such that it had the best profile of comfort, vision and physiological compatibility. Professor Jones rounded off the day among the audience facilitating an interactive quiz looking at the management of anterior eye problems. An enjoyable end to a very well run day. ?