If you haven’t read my first post about glaucoma, I suggest taking a few minutes to read that one prior to starting in here, we’re picking up right where the first left off.
Once we’ve determined that someone is a glaucoma suspect, how do we determine whether or not they truly have glaucoma or not? Is there just a blood test we can order or is there one test we can run that says whether or not it’s present?
Sadly, the answers to these questions are both “no.” It would make my job so much simpler if there was just one test that confirmed whether or not someone had glaucoma. This is where it takes multiple tests and multiple repeats in some cases for us to tell whether or not someone has glaucoma.
For our regular baseline testing, typically most doctors will order photographs of the back of the eye, specifically paying attention to the optic nerve’s physical appearance.
Next we will often run a type of CT scan, but for the eye. A normal CT scan that your primary care doctor might order is too broad and won’t show enough detail that the small, delicate ocular tissues would require. Instead we run what’s called an OCT (the ‘o’ stands for ocular), which measures the thickness of the optic nerves tissue, as well as the nerve fibers that surround the optic nerve. These are often the areas of first damage in glaucoma.
A visual field analysis is ordered usually at the same time as the OCT. This test consists of the patient looking at the back of a white dome shaped instrument with a pirate patch on one eye and clicking a button every time they see a flash of light in their side vision. These tests can help us to track if there is an area of the peripheral vision missing, how much is missing, and if it’s progressing or not. Finally, the last test we often run in terms of the most common tests is one where we place a small lens on the front surface of the eye to view the drain pipes in the eye. Here we are looking to make sure the pipes are opened, narrow, or closed and whether or not there is something blocking those pipes. This procedure is painless and quick usually taking around 20-30 seconds per eye.
While there are other tests that can help to monitor for glaucoma, I won’t go too much into detail with all of them as they’re a little less common.
So we’ve diagnosed you with glaucoma. Now what?
Another brilliant question! There are two main types of treatment to start with, but are then broken down into subtypes from there. The first type is using eye drops, while the second is surgery.
Unfortunately, there is no cure for glaucoma. In fact, we’re still trying to figure out why glaucoma occurs in the first place! Of all the risk factors out there, the only one we can currently control for is the eye pressure. This is why all the treatment options are currently aimed at reducing that pressure as best we can.
Drops
Eye drops can be a great method to treating glaucoma. In the US, it’s often considered the first line of treatment, though that is starting to change a bit as a minor laser procedure is becoming more popular for early cases. There are many different medications on the market to lower the eye pressure. Some work incredibly well, while some lower the eye pressure by a few points only and are typically not first line treatments. These other medications can be used in combination with other stronger medications. One of the most common medications is one that is used in the affected eye just in the evening before you go to sleep. Another is a medication used twice daily. Both work well in many cases, but both have their downsides.
Surgery
There are a lot of different surgeries out there as well. Thankfully, technology and techniques have progressed over time and we now have a minor laser procedure that can help to open the drain pipes wider, lasts for 5-10 years before needing to be repeated, and can often reduce or replace someone’s medications. This is becoming more popular so patients won’t have to use eye drops on a daily basis or reduce the number of eye drops they might need. When patients have surgery, it’s still incredibly important to be watched closely to make sure that the pressures are remaining stable and that there is no progression in the damage.
So wait, doesn’t marijuana lower the eye pressure? Why did you say I
can’t use it for glaucoma?
Right, right… That question! Yes, marijuana does indeed reduce the eye pressure, but there are a number of reasons why it’s not a great method of treatment. Let’s talk about where this myth came from in the first place though, shall we?
In the 70’s and earlier, there were roughly two medications available for treatment glaucoma. One was generally useless and didn’t really lower the pressure by much (maybe 1-2 points, if that!) and the other had terrible side effects (pretty much caused migraines every day!). So when presented with the options for treatment, one being ineffective and one causing terrible side effects, some patients would opt to gamble on hoping they wouldn’t go blind in 5-10 years rather than live with migraines for life.
Around then, reports started coming out of some countries stating that marijuana could reduce the eye pressure. While it is considered a Schedule 1 drug at the federal level still, research really couldn’t be conducted on whether or not this was a good, viable option. The research that was coming out though showed that the eye pressure reduction was somewhat variable from person to person, but more importantly it showed that the length of time marijuana worked was only about 2-3 hours.
With a short duration of 2-3 hours for pressure reduction, the issue becomes that you would have to smoke marijuana every 2-3 hours to keep the pressure in the target range.
Well hey Dr. Nick, that doesn’t sound so bad to me!
That idea might intrigue you at first, but when you really think about it, pretty much every patient I’ve ever spoken with has changed their tune once they hear what this would entail.
So let’s say that you need to do your evening treatment. You smoke at 7 PM and your eye pressure is down. Great! You’re in the target zone. Now it’s 10 PM. You have to smoke again. Okay, that might be fine. But wait, now you have to wake up at 1 AM to smoke again. Okay, that’s maybe a little annoying. Then you have to wake up at 4 AM to dose again. See the pattern?
This means having to smoke or intake marijuana every 3 hours every day for the rest of your life. And while some people might still be on board with that idea, it would mean you can’t drive a car, would have difficulty holding down a steady job, and it can get quite expensive since insurances aren’t covering it at this point for glaucoma (and are unlikely to do so in the future).
Now, most of the eye drops that we use in first line therapy are either dosed once or twice a day. Isn’t 1-2 eye drops per day much easier than having to dose marijuana every 2-3 hours and interrupting your sleep schedule?
I’d certainly say so!
Thanks for reading! I hope you feel like you’ve learned just a bit more about the eye and why it’s important to come in and see us routinely!
Dr. Nick