[Evaluation of the clinical usefulness of the New Aniseikonia Tests].
OBJECTIVE
We performed the following experiments to evaluate the clinical usefulness of the New Aniseikonia Tests (NAT).


METHODS
1. Aniseikonia was induced artificially by wearing a spectacle lens on the right eye and a contact lens on the left eye in myopic but otherwise normal subjects. The amount of aniseikonia detected was compared between the NAT and the Phase Difference Haploscope (PDH). Three different conditions were used with the PDH in order to study whether the fusional background affects the amount of the aniseikonia. 2. The size of aniseikonia was measured by the NAT in normal subjects. We presented the NAT in two ways in order to study if the method of presentation affects the result. One was the regular NAT which consists of 6 pairs of half-moons on each page, and the other one was one pair of half-moons on each page.


RESULTS
The degree of aniseikonia measured was 1.4% smaller in the NAT than with the PDH. Backgrounds did not affect the amount of aniseikonia. Normal subjects showed essentially no aniseikonia regardless of the presentation technique of half-moons.


CONCLUSIONS
NAT may underestimate the degree of aniseikonia, but the difference is too small to contraindicate clinical usage.
Yoshida
M
M
Department of Ophthalmology, Handa City Hospital, Japan.
Sato
M
M
Awaya
S
S
D000328:Adult; D000839:Aniseikonia / Q000175:diagnosis*; D005069:Evaluation Studies as Topic; D006801:Humans; D008722:Methods