Providing Reproducibility and objective control in computer measurement of fusion reserves

Abstract

As is known, the main indicators of the stable functioning of fusion mechanisms – the physiological basis of binocular perception – are the fusion reserves (FR), an accurate assessment of which is still problematic. To measure the FR, a small mismatch between the accommodation and vergence systems is introduced and gradually increasing to reach certain critical angles at which the fusion mechanisms cease to function, as judged by the subjective sensations of the subjects reporting the break of the binocular image into two monocular ones. The subjectivity of such assessments of FR, as well as poorly studied dependence of FR on the parameters of test objects and measurement procedures, make it difficult to determine standard values and to create databases on RF. To overcome these shortcomings inherent in traditional methods of measuring RF, at the end of the last century, attempts were made to use computer methods (Rozhkova et al., 1996 ab, 1998). This article presents the results of a critical evaluation of the computer method for measuring FR using the author’s interactive computer program FUZIYA (Bolshakov, Rozhkova, 2013), which provides for the generation of variable test images on a special display designed for the polarization method of separating the left and right channels of test object presentation. The purpose of this study was to evaluate the accuracy and reproducibility of the measurement results, as well as to test the effectiveness of the previously proposed method to programmatically provide objective control of the binocular image break. The data obtained confirm the prospects of the approach used and make it possible to clarify the specific forms of its rational application.