Thread by @DGlaucomflecken

Let’s learn about eye infestations. If you don’t want to hear about Loa Loa or what happens when Botfly larvae get into your retina, now is the time to mute this thread. Everything from here on out will be horrifying.

Let’s start with cysticercosis, a disease in which sacks full of pork tapeworm larvae develop all over your body. I hear it’s a little itchy. Anyway, these little guys travel along the ciliary nerves and nestle under the retina. I don’t blame them, it’s probably warm in there.

Unfortunately, you can’t blast the subretinal cysts with albendazole or they could break open, incite intense inflammation, and cause the eye to shrivel up and die, a process known as phthisis (because of course ophthalmologists call it that)

Instead, we, and by we I mean anyone but me, have to surgically remove the cysts from under the retina. Here is the cyst removal process in 3 terrifying photos. Who wants to be an ophthalmologist?

How about Loa Loa, everyone’s favorite West African subconjunctival roundworm. Here’s a video courtesy of @shannonwongmd. I’d say this is a good reason not to go live in the Cameroon rainforest. If it makes you feel better (it won’t), Loa Loa typically doesn’t penetrate the eye.

Worms underneath the conjunctiva can be easily removed surgically, but patients still require anti-helminthic medications to kill any remaining micro-worms as well as years of eye worm related psychiatric care.

Next we have the movers and shakers of the eye infestation world: ophthalmomyiasis caused by botfly larvae and diffuse unilateral subacute neuroretinitis (DUSN), caused by raccoon roundworm. They are movers because they literally migrate through your retina.

The first two photos show retinal edema along with the raccoon worm itself just chillin, snacking on some photoreceptors. The last photo shows classic tracks from botfly larvae which have found their way into the retina and clearly have no idea where the fuck they’re going

DUSN is treated by literally blasting the worm with a laser, then treating with topical/intravitreal steroids because the immune system apparently reacts very strongly to dead worms in the eye. Anti-helminthics are also helpful to kill any remaining worms you don’t find.

Botfly larvae aren’t particularly susceptible to anti-helminthic medications, so these must be hunted and destroyed. They mostly hang out on the ocular surface and can be physically removed in surgery. Intraocular larvae must be lasered. PEW! PEW! PEW!

Now I know what you’re probably thinking. THANK GOD I haven’t eaten any raw pork from an open sewer in Honduras or visited Liberia recently, so I don’t have to worry about any eye infestations. Not so fast! Allow me to introduce you to Demodex, aka eyelash mites

Demodex have a commensal relationship with humans. 70% of people have this by age 50, nearly 100% by age 70. Ok take a deep breath, usually demodex doesn’t cause disease, but they have been associated with certain problems like blepharitis, ocular rosacea, and chalazia

If you don’t like the idea that eyelash mites are natural human flora, then definitely don’t watch this video of Demodex extraction by Dr. Christine Sindt from @uiowaeye. They like to hang out at the base of the eyelash follicle

If you get overrun by Demodex, it can be treated with daily lid scrubs with tea tree oil for 6 weeks. Ivermectin works as well.

Thanks for reading and remember, don’t wash your face with stagnant pond water from a developing country, or at least take your contacts out first.