Differential Diagnosis of Wet AMD

John W. Kitchens, MD: Lloyd, we know our older patients have a lot of age-related eye disease issues such as cataracts, glaucoma, dry eyes, exudative age-related macular degeneration, and so on. Briefly, can you parse out things that a primary care doctor might hear from a patient to help them differentiate these things?

Lloyd Clark, MD: Yes. The 3 most important eye diseases I would say in the senior population, are age-related macular degeneration, cataracts, and glaucoma. There’s going to be other things that you hear about, and all the other stuff will send them to the eye doctor. These 3 conditions, when we talk about ophthalmology in particular, are the most common that you’ll run across, again, Dante described the symptoms of age-related macular degeneration. Typically, distortion, blurred vision, but it’s in 1 eye.

Uncommonly, some patients develop simultaneous wet macular degeneration in both eyes, so a hallmark symptom would be a patient coming in and complaining of specific vision complaints in a single eye. There’s other things that can cause that as well, but on a population basis, age-related macular degeneration is towards the top. Cataracts are symmetric typically, so if a patient is having trouble reading, driving, that sort of thing, not having an acute onset. The other thing about macular degeneration is there’s a fairly rapid onset, these symptoms that Dante describes. It’s something that may have occurred over a week or 2 ago, or a month at the most, whereas cataracts progress a lot more rapidly. Finally, glaucoma, is a common condition, but it’s most of the time asymptomatic. That’s a topic for another night, but an important one from a population basis. Unilateral vs bilateral, when we’re trying to differentiate macular degeneration from other conditions, is the most important.

John W. Kitchens, MD: It's interesting, go ahead.

Roger A. Goldberg, MD, MBA: I just have just 1 point, John. I always tell people, and I know you guys know this, but it can be hard for the primary care doctor or non-eye doctor to differentiate purely from a symptom standpoint. If they have classic 1 eye, acute onset, new blurring, or distortion in the central vision, you’re thinking, "Ok, maybe that’s macular degeneration." But I’d say, "Geez, it feels like 90% of the time it’s more ambiguous." I always say that in ophthalmology, the symptoms are nonspecific, but the signs are specific. Patients only complain about maybe a dozen different symptoms that they might be experiencing, and yet there are 500 different retinal diseases, and exponentially more eye diseases in general. It can be a little hard, for a primary care doctor by symptoms alone to decide, "Hey, is this cataract? Is this macular degeneration? Could this be the wet form? It can be hard. When it’s classic, it’s classic, but unfortunately, it’s not always that way.

John W. Kitchens, MD: I always put myself in the position of that primary care doctor who’s having to deal with a hypertensive patient in one room, the flu in the other room, and COVID-19 in the next room and that patient with plenty of vision loss. Who should they refer this patient to, Roger, to get any kind of vision loss explored?

Roger A. Goldberg, MD, MBA: If it’s acute vision loss, getting that assessment done quickly, is the most pivotal thing, and it’s largely dependent on the community where that primary care doctor is practicing. I’m in the Bay Area, and both general ophthalmologist and retina specialists are relatively plentiful, retina specialists, are so attuned to seeing patients the same day or next day, it’s part of our normal workflow, that they call us and say, "Hey, I’ve got a patient with acute vision loss." We always see them, because we can’t tell on the phone either whether it’s a retinal issue or not, and then we can help that primary care doctor figure out if it wasn’t for us, who the right doctor or who the right eye care specialist is going to be. If it’s a subacute or chronic type, “I’m having trouble reading. I’m having trouble seeing the menu in the restaurant and I have to pull my flashlight out." You could start with a general eye doctor, even sometimes an optometrist, depending on the community, or a general ophthalmologist.

Dante J. Pieramici, MD: The key is to make sure whoever’s doing the examining, does a complete eye exam. You want to send it to an eye doctor, be it an optometrist, general ophthalmologist, or retina specialist who’s going to examine the eye from the front to the back, including doing a dilated examination where they can really check. You don’t want to send them to an eyeglass place, where they check for eyeglasses and then send them on their way. That’s the only thing I would just add, what Roger said is great, and I just put that point in there.

John W. Kitchens, MD: Dante, that’s a really important point, dilated eye examination.

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Transcript Edited for Clarity