Body system: EyeRegulation: 38 CFR § 4.79
Post-chiasmal disorders affect the part of the visual system BEHIND the optic chiasm (where the optic nerves cross at the base of the brain). The damage causes characteristic visual field defects, often homonymous hemianopia (matching half-field loss in both eyes) or related patterns. The VA rates this condition under the General Rating Formula for Diseases of the Eye (38 CFR § 4.79), using whichever path yields the higher evaluation: visual impairment (especially visual field defects under DC 6080) OR the Incapacitating Episodes ladder (10% for 1-2 treatment visits per year, up to 60% for 7 or more visits).
Rating levels
- -1% — DC 6046 post-chiasmal disorders are rated under 38 CFR § 4.79. PATH 1: visual impairment, particularly visual field defects (homonymous hemianopia and similar patterns where the visual field is cut in matching halves between the two eyes because the damage is behind the optic chiasm), rated under the standard chart codes (DC 6080 visual field, DCs 6066-6081 acuity, DC 6090 muscle). PATH 2: the Incapacitating Episodes ladder shown below. Whichever path yields the higher evaluation is what the VA assigns.
- 60% — You qualify for 60% if your post-chiasmal disorder required 7 or more clinic visits specifically for treatment during the past 12 months (intravitreal or periocular injections, laser treatments, systemic immunosuppressants or biologic agents, or other surgical interventions). This is the highest tier on the Incapacitating Episodes path of the General Rating Formula for Diseases of the Eye (38 CFR § 4.79). Visual impairment may yield a higher rating in some cases, in which case the higher value applies.
- 40% — You qualify for 40% if your post-chiasmal disorder required at least 5 but fewer than 7 clinic visits specifically for treatment during the past 12 months. This rating applies under the Incapacitating Episodes path of the General Eye Formula when it yields a higher evaluation than the visual impairment path.
- 20% — You qualify for 20% if your post-chiasmal disorder required at least 3 but fewer than 5 clinic visits specifically for treatment during the past 12 months. This rating applies under the Incapacitating Episodes path of the General Eye Formula when it yields a higher evaluation than the visual impairment path.
- 10% — You qualify for 10% if your post-chiasmal disorder required at least 1 but fewer than 3 clinic visits specifically for treatment during the past 12 months. This rating applies under the Incapacitating Episodes path of the General Eye Formula when it yields a higher evaluation than the visual impairment path.