Abstract
Purpose :
Neuro-ophthalmologists and strabismologists typically try to distinguish between binocular and monocular diplopia using specific questions. The purpose of this study was to evaluate the sensitivity and specificity of these questions using a patient questionnaire format.
Methods :
64 adults with either monocular (n=26) or binocular (n=38) diplopia, confirmed on exam, completed a questionnaire. Included were 5 conventional questions to distinguish monocular and binocular diplopia and 3 questions aimed at identifying patients with dry eye-related monocular diplopia, all using 5 response options: never, rarely, sometimes, often, and always. Sensitivity and specificity of each question was evaluated by comparing always or never to the other options. The questions on whether the double vision goes away when closing the left and right eye were combined for analysis.
Results :
The gold standard question, “Does the double go away when you close the right/left eye?” was 100% specific for binocular diplopia, but only 78% sensitive. Questions expected to be specific for monocular diplopia (Does the double look like a shadow, overlapping images, and have no space between the images?) had good specificity (86% to 95%), but very poor sensitivity (19% to 32%). Questions expected to be specific for monocular diplopia due to dry eye (improve with blinking, worse after TV and reading), had good specificity (80% to 97%), but even worse sensitivity (0% to 23%).
Conclusions :
The conventional questions typically used by neuro-ophthalmologists and strabismologists to distinguish between binocular and monocular diplopia had good specificity but poor sensitivity. Even the gold standard question, “Does the double go away when you close the right/left eye?” was only 78% sensitive for binocular diplopia. The other conventional questions did more poorly and the dry-eye induced diplopia questions had particularly poor sensitivity. Although patient recall of symptoms can be very helpful in distinguishing monocular and binocular diplopia, in many cases only the clinical exam will be diagnostic.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.