10-Prism-Diopter Fixation Test for Amblyopia

ABSTRACT

PURPOSE: To evaluate the clinical usefulness of the 10-prism-diopter (PD) fixation test in the diagnosis of amblyopia. METHODS: The study comprised 132 children (42 normal, 90 amblyopes) who underwent the 10-PD fixation test and stereoacuity test. The sensitivity, specificity, false-positive and false-negative rates of the 10-PD fixation test were analyzed according to the clinical diagnosis. RESULTS: The 10-PD fixation test sensitivity was 86%, the specificity was 61%, the false-positive rate was 17% and the false-negative rate was 24%. Data showed agreement between the 10-PD fixation test and the stereoacuity test (gamma=0.737, p=0.000). The results in the 10-PD base-down test and base-out test also showed agreement (gamma=0.779, p=0.000). CONCLUSIONS: The 10-PD fixation test is a simple and useful method in detecting amblyopia.