Affiliations: University Eye Hospital, Department II Tübingen,
Germany | Department of Neuroradiology, Radiological Clinic,
Tübingen, Germany | Department of Medical Psychology and Behavioural
Neurobiology, Tübingen, Germany
Note: [] Corresponding author: Department II, University Eye Hospital,
Schleich-straße 1216, D-72076 Tübingen, Germany
Abstract: Clinical detection and follow-up of homonymous visual field defects
require appropriate perimetric procedures: since postgeniculate lesions are
usually characterised by absolute scotomata, time consuming threshold methods
can be replaced by supraliminal strategies with comparatively high stimulus
densities. Compared with equidistant rectangular grids, a centripetal stimulus
condensation represents the physi-ological conditions more adequately and thus
is more effective. It allows one to differentiate central changes of the visual
field, like macular sparing or splitting, which also interfere with reading
performance. This procedure requires test points to be located to either side
of the verti-cal meridian, rather than directly on it. Multimodal assessment of
visual subfunctions (using static, kinetic or colour test points, random dot
patterns or optokinetic stimulation) specifies the effect of the lesion in
different channels or regions of the visual pathways. Automation of perimetric
procedures and continuous monitoring of fixation are important tools, enhancing
the quality of examination and follow-up. The above mentioned psychophysical
techniques for detection of functional defects and documentation of eventual
recovery, as well as matching neuroimaging findings, are demonstrated by
illustrative cases.
