Short-wavelength automated perimetry in neuro-ophthalmologic disorders
J. L. Keltner and C. A. Johnson
Department of Ophthalmology, School of Medicine, University of California-Davis, Sacramento, USA.
OBJECTIVE: To evaluate the efficacy of short-wavelength automated perimetry
(SWAP) in the assessment of patients with neuro-ophthalmologic disorders,
especially optic neuropathies. METHODS: A modified Humphrey field analyzer
was used to perform standard automated perimetry and SWAP, a technique that
isolates the activity of short-wavelength-sensitive ("blue") mechanisms.
Forty patients (80 eyes) were evaluated by SWAP and standard automated
perimetry. Thirteen patients (26 eyes) had recovered from optic neuritis
and/or multiple sclerosis, 15 (30 eyes) were in various stages of treatment
for pseudotumor cerebri, and 12 (24 eyes) had other miscellaneous
neuro-ophthalmologic conditions. Six additional patients (12 eyes) with
neuro-ophthalmologic conditions were tested twice on different days during
a 2-week period, with the order of SWAP and standard perimetric testing
being reversed on the second day. RESULTS: Of the 80 eyes tested, 38 (48%)
had SWAP visual fields that were worse than standard automated perimetry
results; 29 (36%) showed no difference between standard and SWAP visual
fields; and 13 (16%) had standard automated perimetry results that were
worse than SWAP visual fields. Of the 26 eyes in patients with optic
neuritis and/or multiple sclerosis, 15 (58%) had SWAP results that were
worse than standard visual fields. Ten (33%) of the 30 eyes with
pseudotumor cerebri had SWAP results worse than standard automated
perimetry results, and 13 (54%) of 24 eyes with miscellaneous
neuro-ophthalmologic conditions had SWAP results worse than standard
automated perimetry results. For the 12 eyes undergoing repeated testing,
SWAP visual fields were worse when they were performed last, perhaps
indicating that some fatigue effect was present. This was observed for
standard visual fields as well, but to a smaller extent. CONCLUSIONS:
Preliminary findings suggest that SWAP may be useful in detecting certain
neuro-ophthalmologic deficits more readily than standard automated visual
field testing, especially for optic neuritis and multiple sclerosis.
Further evaluations will be necessary to define the effects of fatigue for
SWAP visual fields in neuro-ophthalmologic disorders.
