Diplopia is described as being intractable when there is inability to both fuse the two images and suppress the second image. Intractable diplopia persists despite achieving ocular alignment using either prisms, lenses,vision therapy,extraocular muscle surgery, or botulinum toxin injection. Treatment usually resorts to occluding or fogging the patient’s
nondominant eye. Often times, however, adults having other causative mechanisms for supposedly persistent diplopia are able to achieve comfortable single vision with treatment that either establishes fusion or reactivates a preexisting sensory adaptation.
This case series reviews these other causes of diplopia.
