ISSN: 2472-4971
Hans C Fledelius
Purpose: To direct attention to a generally ignored cognitive element in chiasmal symptomatology, with the aim of reducing the diagnostic delay in such cases, where complaints are typically vague. A minority of chiasmal patients thus present with cognitive ignorance or mis-interpretation in visual space, probably caused by conductive loss of information as usually required for higher brain centres to induce relevant eye movements.
Methodology: Personal experience from more than 30 years’ neuro-ophthalmological service is overviewed, primarily based on observation of abnormal behaviour during routine clinical testing for visual acuity (eventually summing up to 64 patients). Neuro-psychological testing and extended imaging (including functional positron emission tomography imaging as a pilot study) were carried out in part of the series.
Major findings: A main feature has been lateralizing behaviour during unilateral visual acuity testing, showing a lateral ignorance on the board. Many also presented with inability to read print and a few had bizarre misinterpretations in visual space.
Conclusions: The cognitive aspects have gained little attention in the literature. As a guide to early diagnostic attention, however, acknowledging aberrant behaviour in the eye clinic may b