|Before checking for the presence of visual field defect, make sure
that the patients can see the target that you use to test the visual field.
Otherwise, you may be wasting valuable time on a blind eye. While testing
the field always begin with the peripheral field before moving to the central
field. If there were a peripheral field defect check if it obeys the midline.
In the absence of a peripheral field defect, the most likely case in the
examination is a central scotoma, demonstrate this with a red pin. If you
do not find any field defects, the patient may have an early bitemporal
hemianopia which only becomes obvious if you compare the temporal and nasal
field with a red object (the red object on the temporal will be less bright).
Common visual field defects
homonymous hemianopia / quadrantanopia
Less common cases
altitudinal field defect