Incomitant Strabismus/Module 1: Clinical Investigations of Incomitant Strabismus/Part 6: Assessing Diplopia and BSV

Assessing Diplopia
Interpretation of Diplopia Chart

Description
 * The diplopia chart is a record of the position of diplopic images in the 9 positions of gaze.
 * It can be used in any co-operative patient with an incomitant deviation who is experiencing diplopia.

Method
 * Patient sits still, with head straightened.
 * Patient wears red and green goggles (but this is not mandatory) and views a pen torch, held by the examiner at a distance of 50 cms.
 * Move the torch into the 9 positions of gaze.
 * Question the patient about the position of the diplopic images in each position relative to and commencing in the primary position. If a linear torch is available (or even a pen!), ask about the presence of torsion as patients rarely volunteer this information.

Recording
 * Record the results on the grid as if the examiner were the patient, i.e. diplopia recorded on the left hand side of the grid are the diplopic images as seen to the patient's left hand side.
 * Record which goggle was in front of the right eye. (It is convention that the red goggle is in front of the right eye).
 * Record the distance of the fixation light if other than 50cms (e.g. 1m)
 * Record the distance of separation of images and the tilt.
 * Record which eye "sees" which image.