Third International Visual Field Symposium - Imaging and Perimetry ...

field. A flicker attachment, originally designed by Dr. Nakabayashi (1967)
was inserted in the optical pathway of Autoplot Tangent Screen made by
Bausch and Lomb.
Patients were chosen from those who visited the outpatient clinic and
neuro-ophthalmology clinic of our institutions during the past 8 years.
RESULTS AND DISCUSSION
Figure 2 is a typical case of optic neuritis in which kinetic Goldmann pe-
rimetry failed to detect central scotoma. However, in central flicker field
studies we detected central scotoma. The central vision was 0.3 and central
CFF was 15 Hz. We could easily come to a diagnosis of optic neuritis.
Figure 3 is a typical course of recovery of vision and CFF in optic neuritis.
Following steroid therapy, vision was recovered first, followed by the recov-
ery of CFF. After one month and a half, the patient complained of blurring
of vision. Although there was very small reduction of visual acuity, CFF was
reduced remarkably, indicating that there was recurrence of optic neuritis.
As far as we rely on central vision and ordinary kinetic perimetry and
campimetry, it is not easy to detect very early changes of optic nerve lesion
or recurrence of optic neuritis.
Various types of recovery of central vision and central CFF are shown in
figure 4. Figure 5 is a schematic drawing of the course of recovery of vision
and central CFF in optic neuritis. Vertical lines indicates the time of obser-
vation. If we see a patient in a very early stage, we can detect dissociation of
vision and CFF as shown in type IV. If we see a patient at the time of
lowest vision and CFF, the course of recovery and CFF may vary from case
to case. This observation of dissociation of vision and CFF is most impor-
tant in the diagnosis of optic nerve diseases in their early stages.
Normal values ranges from 40 to 50 Hz and the lowest limit is 35 Hz. If
central CFF is less than 25 Hz, we can definitely make a diagnosis of optic
nerve disease even though vision is restored within a normal range. There-
fore, the ‘flicker test’ is equally or even more important than the examina-
tion of pupillary reflex.
Based on our experience in the past 8 years, we can conclude that the
‘flicker test’ is useful in the diagnosis of optic neuritis and papillits, toxic
amblyopia, optic nerve injury, compression of the optic nerve by the tumor.
This test is also useful in the differential diagnosis of atrophic stage of
papilledema, optic atrophy and disc pallor only, amblyopia, refractive
anomaly, disturbance of accommodation, hysteria and simulation.
SUMMARY
We developed an apparatus for the measurement of central CFF and used
this on over 10,000 cases during the last 8 years. It was confirmed that CFF
is remarkably decreased in optic nerve or 3rd neuron diseases and this
‘flicker test’ is the most reliable test to be used in the diagnosis of optic
nerve diseases in neuro-ophthalmological practice.
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