Evaluation of baseline-related suprathreshold testing for quick determination of visual field nonprogression
M. L. Araujo, W. J. Feuer and D. R. Anderson
Bascom Palmer Eye Institute, Miami, FL 33101-6880.
OBJECTIVE--To evaluate a commercially available means of baseline-related
suprathreshold examination designed to detect visual field worsening.
DESIGN--Patients for whom results of a baseline series of static-threshold
visual field examinations were available underwent both a second
static-threshold examination (full-threshold strategy; average time, 15
minutes) and a baseline-related suprathreshold examination
("fast-threshold" strategy; average time, 5 minutes). RESULTS--Most of the
1702 points examined were apparently unchanged from baseline, showing with
either method only the degree of variation expected from the measurement
inconsistency (short-term fluctuation). For points that did show a change,
the changes shown by the two methods were correlated. Change in the field
as a whole, represented by a cluster of locations showing deterioration,
was evident more frequently with the standard testing strategy: 11 of 37
field examinations showed deterioration by both methods and an additional
11 examinations showed deterioration by the full-threshold method only.
CONCLUSIONS--Each examination method identified pointwise changes not
detected by the other, the combined effect of false-positive errors
(imperfect specificity) and false-negative errors (imperfect sensitivity)
with each of the two methods. The findings relating to clusters could
represent a better sensitivity of the full-threshold method in detecting
visual field deterioration, a better specificity of the suprathreshold
method, or both.