Diplopia is defined as seeing two images of an object at the same time.

This condition may be caused by a weakness of one or more of the extraocular muscles supplied by the third, fourth and sixth cranial nerves. The motor nerves may be affected by abnormalities from trauma, hemorrhage, inflammation, neoplasm, aneurysm, or demyelination diseases. The condition may also occur when there is a displacement of the globe, as in proptosis. Diplopia may also be due to the condition, internuclear ophthalmoplegia, as seen in multiple sclerosis (see Diagnostic Code: 8018 Multiple sclerosis).

Weakness of the eye muscles supplied by the third, fourth and sixth cranial nerves may result in strabismus; diplopia; dilated pupil; loss of accommodation; pain around the eye; and drooping of the eyelid. Diplopia may also occur without muscle weakness, as seen when the eyeball is displaced downward (proptosis) in exophthalmus (see diagnostic code: 7900 hyperthyroidism). Palsy of the third cranial nerve is a common condition in diabetes mellitus (see diagnostic code: 7913 diabetes mellitus).

Eye examinations include: external examination; eye alignment cover test; visual fields; visual acuity; ophthalmoscopy; slit lamp; and pupil examination (PERRLA).

Wearing an eye patch may alleviate double vision. Treatment of the underlying medical disorder may resolve the double vision.

Pain may last a few days. The eye may recover its normal function in 2 to 3 months.

• Refer to the manual (M21) for additional guidance on considering service connection for diplopia.

• May be entitled to special monthly compensation where the Veteran has a single service-connected disability rated as 100% with additional service-connected disability or disabilities independently ratable at 60% or more, which are separate and distinct from the 100% service-connected disability and involves different anatomical segments or bodily systems. See  38 CFR 3.350(i)(1) – Special Monthly Compensation (SMC).

• Consider entitlement to specially adapted housing under 38 U.S.C. 2101(a)(2)(A)(i) if there is visual impairment to the degree specified in 38 CFR 3.809(b)(2).

• The veteran, spouse, surviving spouse or parent will be considered in need of regular aid and attendance if he or she is blind or so nearly blind as to have corrected visual acuity of 5/200 or less, in both eyes, or concentric contraction of the visual field to 5 degrees or less (38 CFR 3.351(c)(1)).

• Consider entitlement to automobile allowance and/or automobile adaptive equipment if there is visual impairment to the degree specified in 38 CFR 3.808(b)(3).

• In accordance with 38 CFR 4.31, diplopia that is occasional or that is correctable with spectacles is evaluated at 0 percent.

• Review for entitlement to special monthly compensation under 38 CFR 3.350.

• An evaluation for diplopia will be assigned to only one eye. When a claimant has both diplopia and decreased visual acuity or visual field defect, assign a level of corrected visual acuity for the poorer eye (or the affected eye, if disability of only one eye is service-connected) that is: one step poorer than it would otherwise warrant if the evaluation for diplopia under diagnostic code 6090 is 20/70 or 20/100; two steps poorer if the evaluation under diagnostic code 6090 is 20/200 or 15/200; or three steps poorer if the evaluation under diagnostic code 6090 is 5/200. This adjusted level of corrected visual acuity, however, must not exceed a level of 5/200. Use the adjusted visual acuity for the poorer eye (or the affected eye, if disability of only one eye is service-connected), and the corrected visual acuity for the better eye (or visual acuity of 20/40 for the other eye, if only one eye is service-connected) to determine the percentage evaluation for visual impairment under diagnostic codes 6065 through 6066.

• When diplopia extends beyond more than one quadrant or range of degrees, evaluate diplopia based on the quadrant and degree range that provides the highest evaluation.

• When diplopia exists in two separate areas of the same eye, increase the equivalent visual acuity under diagnostic code 6090 to the next poorer level of visual acuity, not to exceed 5/200.