Nonsurgical management of binocular diplopia induced by macular pathology

Objective: To treat binocular diplopia secondary to macular pathology. Methods: Seven patients underwent evaluation and treatment. All had constan t vertical diplopia caused by various maculopathies, including subretinal n eovascularization, epiretinal membrane, and central serous retinopathy. Vis ual acuity ranged from 20/20 to 20/30 in the affected eye. All except 1 pat ient had a small-angle, comitant hyperdeviation with no muscle paresis. Sen sory evaluation demonstrated peripheral fusion and reduced stereoacuity. Ne ither prism correction nor manipulation of the refractive errors corrected the diplopia. A partially occlusive foil (Bangerter) of density ranging fro m 0.4 to 1.0 was placed in front of the affected eye to restore stable, sin gle vision. Results: The Bangerter foil eliminated the diplopia in all patients. Two pa tients elected not to wear the foil; 1 patient was afraid of becoming depen dent, and the other was bothered by the visual blur. Visual acuity in the a ffected eye was reduced on average by 3 lines. All patients maintained the same level of sensory fusion, with only 2 having reduced stereoacuity. Symp toms returned when the foil was removed or its density was reduced. Conclusion: Low-density Bangerter foils provide an effective, inexpensive, and aesthetically acceptable management for refractory binocular diplopia i nduced by macular pathology, allowing peripheral fusion to be maintained.