Cause of monocular diplopia diagnosed by combining double-pass retinal image assessment and Hartmann-Shack aberrometry.

PURPOSE To report an advanced optical procedure developed for the diagnosis of a particular case of diplopia. METHODS This approach combined the quantification of the level of intraocular scattering by using an Objective Scatter Index provided by a double-pass instrument (Optical Quality Analysis System) with the analysis of higher order aberrations using a Hartmann-Shack wavefront sensor. RESULTS The value of the Objective Scatter Index revealed increased intraocular scattering; the Hartmann-Shack images showed the existence of an optically differentiated area at the upper region of both crystalline lenses. Simulation of retinal images computed from the wavefront maps confirmed that, under low luminance conditions, this inhomogeneous region of the lens was included in the pupil, generating a secondary image and therefore the diplopia. CONCLUSIONS This report demonstrates the potential of combining two objective optical methods to show the presence of minor lens opacities that may severely degrade quality of vision.