How good are we at assessing driving visual fields in diabetics?

Purpose/background Following laser panretinal photocoagulation (PRP) for pr oliferative diabetic retinopathy, patients are at risk of failing the UK dr iving visual field lest due to loss of peripheral field. Although a definit ion of the minimum field requirement exists, differences in its interpretat ion may influence whether fields pass or fail. Currently it is not known ho w fields are interpreted in practice nor to what extent this affects failur e rates. Methods Uniocular and binocular Esterman visual fields from 60 diabetic pat ients following PRP were examined both by the chairman of the Visual Standa rds Sub-Committee of the Royal College of Ophthalmologists and separately b y four consultant ophthalmologists. The results were analysed (1) to assess the extent of agreement and (2) to identify, from the chairman's results, the field deficits that are still compatible with passing. Results Agreement was generally good for binocular fields but was only mode rate for uniocular fields. In up to 15% of binocular fields and 43% of unio cular fields the chairman's decision was different from that of the consult ants. Several key aspects of the field that influence a pass/fail decision are identified. Conclusions Substantial differences in the assessment of driving visual fie lds following RPR currently exist between consultants and the chairman of t he Visual Standards Sub-Committee. Using the information presented here to guide assessment it is now possible to reduce this variation.