Sir,

With reference to ‘Progressive Glaucoma in Patients with Alzheimer's Disease’ (Bayer and Ferrari1), is it not time for an evidence-based national protocol for visual field analysis in glaucoma? It used to be common clinical knowledge that:

  1. 1

    disc changes precede visual field change in glaucoma;

  2. 2

    pathologically cupped discs are quite compatible with normal visual fields;

  3. 3

    true glaucomatous field defects are never associated with plumb normal discs.

Is it necessary to get caught up in the pseudo-science of statistically significant visual field progression via Pattern Standard Deviation in patients with Alzheimer's disease? Such changes at the optic nerve head as described would surely have made the point alone without resorting to a refined visual field programme, potentially full of error and certainly profligate when one considers visual field analysis throughout the beleagured health service. For comorbidity in glaucoma clinic patients, see Beck and Karseras.2