[Critical (foveal) flicker fusion frequency (CFF) is helpful in differential diagnosis of organic lesions from orthoptic amblyopias].
OBJECTIVE
To measure critical (foveal) flicker fusion frequencies (CFF) in normal eyes, unilateral maculopathies and neuropathies and in orthoptic amblyopias.


METHODS
A newly developed apparatus (4F) with LED's measured subjective foveal CFF by ascending and descending mode in a group of normals and patients.


RESULTS
The apparatus (4F) measures temporal resolution. Foveal CFF ist more reduced in neuropathies than in maculopathies. In contrast, CFF in amblyopic eyes is hardly reduced, in most cases equal or better than in the dominant fellow eye. This is independent from the visual acuity of the amblyopic eye.


CONCLUSIONS
CFF testing is useful in the evaluation of unexplained (unilateral) reduction of visual acuity. A dissociation between visual acuity and CFF (within normal range) is present in cases of amblyopia.
Univ.-Augenkliniken Zürich, Zollikerberg-Zürich.
H
H
Wildberger
A
A
Junghardt
A
A
Neetens
P
P
van den Ende
D000550:Amblyopia / Q000175:diagnosis* / Q000503:physiopathology; D003937:Diagnosis, Differential; D005425:Flicker Fusion / Q000502:physiology*; D006801:Humans; D008266:Macula Lutea / Q000503:physiopathology; D009901:Optic Nerve Diseases / Q000175:diagnosis* / Q000503:physiopathology; D012164:Retinal Diseases / Q000175:diagnosis* / Q000503:physiopathology; D012684:Sensory Thresholds / Q000502:physiology; D014792:Visual Acuity / Q000502:physiology