Loss of vision in the ageing eye

Age and Ageing, March, 1997 by A.J. Bron

Low vision aids (LVAs) cannot replace vision, have disadvantages, and require adaptation by the patient. They may be `no-tech', like moving a TV set nearer, or employ magnification or better contrast. At all times aids must be customised to suit the needs of individual patients, and realistic aims, motivation, and good support are needed.

LVAs may be supplied on loan after testing by Health Service-employed optometrists, through schools of optometry, through private optometrists or opticians, or be self-selected.

At Moorfields Hospital, some 10% of patients at the low vision clinic achieve their targets with only refraction and advice on illumination, while 5% fail because of poor motivation or very severe visual impairment.

For the future the requirement is for improved awareness of the possibilities of helping patients, of appropriate methodology, and the cost-benefits of different methods.

Conclusions

Professor Bron concluded by going through the main point made: that the visual system was made to last, with a potential for adequate function up to 120 years; that not all blind people are recognized and that some can be helped by simple refraction; that IOP is not the whole story in glaucoma; that the lens is a model for ageing, with identified mechanisms of damage and defense; that optical radiation, particularly blue light, may be the main means of damage to the RPE; that ARMD remains the main problem in prevention and treatment, followed by glaucoma, diabetic eye disease, and cataract. He concluded that we should take into account more than visual acuity alone, and that there are many specific methods to help.

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