Purpose: The aim of the study was the measurement of fusional, dissociated and heterophory vergences associated with the phoropter both in the open field, by comparing the data obtained in monocular and binocular prismatic apposition. Most of the studies in the literature, in fact, have compared the various measurement methods with each other but have not made a direct comparison between the results in monocular and binocular conditions.
Methods: 40 subjects (age 22,5 ± 3,1) were examined in which the lenses of the subjective refraction performed at the phoropter were worn during the tests, then balanced with Humpriss in the open field. For each subject, the following were measured from afar (6 metri) and near (40 centimetri): the smooth fusional vergences (phoropter) and jumps (open field), the dissociated heterophorias by means of the Von Graefe test (phoropter) and the of Maddox modified Thoringhton (open field) and finally, the heterophoria associated for distance, through the cross and needle test both to the phoropter and in open field and the associated heterophorias for near through the Wesson card (phoropter) and the Mallet Unit (open field).
Results: Tests on the data revealed significant differences between the test results obtained with monocular and binocular prismatic apposition, and it was determined that there is a statistically significant difference between the two measurement methods, especially with regard to the data in the open field. The difference in merger virginity was greater above all on breakdowns and recoveries for the most part negative and for the least part positive. In the heterophorias the difference was significant above all for the data in the open field, probably due to the greater presence of fusional recalls.
Conclusions: The results of the study showed a new perspective on binocular vision investigation methods. In this regard, in order to have a more specific and broader understanding of the commonly used procedures, it would be useful to deepen the study with a larger sample both in terms of number and variety.
