In 2004, I went in for an eye exam because I’d been having severe headaches. Doctor Number One did the exam and wrote a prescription; I bought a pair of glasses and two years’ worth of contacts, and my headaches disappeared immediately.

In 2006, I went back to Doctor Number One to get the prescription refilled. A few weeks after getting the new batch of contacts, my long-distance vision seemed ever-so-slightly fuzzier than it did with my old contacts, or with my glasses. I figured it was my imagination, or perhaps some minor difference between the old batch and the new batch of contacts that I’d get used to.

In the summer of aught-seven, I decided to get a new pair of glasses and some prescription sunglasses. I went back to Doctor Number One’s office for an eye exam. He said my prescription was exactly the same as when I’d first seen him in 2004—which surprised me due to the aforementioned slight fuzziness.

Well, the problem became more pronounced over the last year. My vision with glasses was fine, but in contacts wasn’t so great. I had no idea why. Had Doctor Number One screwed up? Had a technician screwed up? Was the difference psychosomatic in nature? Who knew?

So I decided to have a different doctor check the ol’ eyeballs. I made an appointment with Doctor Number Two for this past Wednesday. Right before I left for the appointment, I checked the power labels on my last two boxes of contact lenses. I checked the box with the “R” (for “right”) label: those contacts had a power of -0.50. I checked the other box, with the left-eye contacts: they had a power of -0.75.

I wore my glasses to the office, and the technician asked to see them. She put them in some device to determine the prescription on the glasses. She gave them back, and I went into the back room to have some air puffed into my eyes, to read some fuzzy numbers and some clear numbers, and to have the inside of my eyeballs photographed.

Now, at Doctor Number One’s office, they’d photographed the inside of my eyeballs and showed it to me on a flat screen, which was pretty cool. But at Doctor NumberTwo’s office, they mapped that photograph onto a three-dimensional wireframe of my eyeball, which included my iris and pupil on the other side. It looked like the Death Star, with one hemisphere on fire. It was awesome. Instantly, I had greater confidence in Doctor Number Two…

…until the technician asked what my prescription was. I told her: -0.50 right, -0.75 left. She scrunched her forehead, looked at some numbers on her computer, and asked me to repeat it. I did. She asked if I was sure. I told her that I’d double-checked it this morning.

She said, “That’s the opposite of your glasses.”

…

Maybe I misremembered the powers on my contact lens boxes. That would be the simplest explanation of the confusion. When I got home, I checked the boxes again. The problem was not my memory, because the boxes still said -0.50 right and -0.75 left. So why the hell were my glasses the other way around?

I hopped on the internet and looked up information about powers and prescriptions. Turns out that terms like “right eye” and “left eye” are too pedestrian for optometrists; they call them the “oculus dexter” and the “oculus sinister.” I thought, “Why not just use ‘right’ and ‘left’? I’d get those oculus things backwards all the time.”

Click.

I went through my medical file folder, hoping to find my actual prescription—as in, the piece of paper with Doctor Number One’s signature. I found it:

OD [a.k.a. “right”] -0.75
OS [a.k.a. “left”] -0.50

Somewhere out there–perhaps in a contact lens factory, perhaps in an optometrist’s office–is someone who, two years ago, had a very, very simple job: “Put stickers with the letter ‘R’ on six particular boxes of contact lenses. Do not put those stickers on any other boxes.”

That someone pooched it. I’d been wearing my contacts backwards for two years.

I don’t think I can sue anybody. Three reasons: I don’t know whom to sue, I don’t see how I can prove damages, and I don’t want to draw any more attention to the fact that I feel like a damned idiot for not figuring it out sooner.

…

Flashback to the previous ellipsis: Doctor Number Two came in, showed me some more fuzzy numbers, showed me some more clear numbers, played the “1 or 2” game with various lens combinations, and shined bright lights in my eyes for a few minutes. He gave me a new pair of contacts to try out, and made a checkup appointment for next week. After a few minutes of adjusting, my long-distance vision was sharp. Jackpot.

When I pick up my new batch of contacts, I’m going to double- and triple-check every single package and label right there in the office.