An 84-year-old woman notices an alteration in color perception. Specifically she describes a greenish hue to the vision in her right eye only and says when she looks at red objects they appear brown.
She has been aware of this change in colors for 3 days. Her past ocular history is notable for mild corneal endothelial dystrophy, a small area of RPE atrophy in the fovea OD (stable for 6 years with thinning on OCT), cataract OS, and pseudophakic OD (4 months status post uncomplicated cataract surgery).
On examination, visual acuity is 20/25 OU, pupillary response, extraocular motility, and color vision with Ishihara plates is normal in each eye. Red saturation tested with a red eye drop bottle cap is unequal: red cap appears bright red OS but looks a muddy, darker red OD. Anterior segment exam shows mild cornea guttata OU, a well-positioned monofocal lens implant in a clear capsule OD, and a cataract OS. Posterior segment exam shows an unchanged small RPE disturbance in the fovea OD without subretinal fluid or hemorrhage. The macula is normal OS, and the optic nerves appear healthy OU.
What process are you most concerned about, and what additional tests might be helpful in determining the diagnosis?
The answers: Wet age-related macular degeneration (AMD), and Amsler grid testing, optical coherence tomography (OCT), and fluorescein angiography (FA).
Additional findings: Amsler grid testing is normal; there is no metamorphopsia in either eye. An OCT is obtained (OD image shown below; OS image is normal with normal macula thickness):
How would you manage this patient?
The Stratus OCT image shows a normal contour without thickening of the macula or RPE detachment, rather the macula is thinner than average. However, blood in the macula can cause an alteration in color vision as described by this patient, and I have seen this occur. Therefore, I urgently referred this patient to a retina specialist to rule out a choroidal neovascular membrane, and she was examined the next day. A Cirrus OCT was normal, but a FA demonstrated a small area of leakage from an occult membrane. She was treated with EYELEA and her vision has remained stable at 20/25.