What is Superior Semicircular Canal Dehiscence (SSCD)?

Let’s be honest. I had never even remotely heard of this thing before. Heck, the only part of the ear I knew about was the eardrum. When the ENT called (the one before the one at OHSU…the second time at OHSU) and said that this might be a diagnosis, obviously I went online and googled that ish. As I’m reading about all the symptoms, I’m thinking in my head, “Yep,” “Oh, that’s the technical name for that,” and “Wow, this sounds exactly like me.” Here you go, folks. SSCD in a blonde, twenty-something’s words.

Let’s break it down, shall we?

Superior Semicircular Canal: As you can see in the photo below, the semicircular canal is located in the inner ear. It is lined with cilia (tiny ear hairs…gross, right?) and filled with a fluid called endolympth. Every time the head moves, that fluid moves the cilia. The movements of the cilia are communicated to the brain, making it a motion sensor of sorts. The brain then knows how to keep the body balanced. The semicircular canal has three (main) parts: horizontal, posterior, and superior canals, each of which provides a separate sense of directional balance. The superior canal detects head rotations on the anterior-posterior axis (up and down movements of the head).

The ear. Duh.

Dehiscence: There are a number of different kinds of dehiscence in the medical world. But here’s what it means in terms of SSCD: it is a thinning or opening of the bone in the skull that covers the superior semicircular canal. In my case…the bone is missing. I’ve tried to show it in the photo below. The right side (labeled ‘normal’)…look below the ‘m’ in normal…that’s what it should look like. The left side (labeled ‘dehiscence’)…look below the first ‘e’ in dehiscence. See the big black space? That’s where the bone has eroded away. There isn’t really a clear answer as to why the bone has eroded, but it has.

Inside my head...I know, really, who wants to be there?!? 

Diagram of SSCD

About 17 years ago, a doctor by the name of Lloyd B. Minor at Johns Hopkins University was doing his doctor thing. He found that eye movements evoked by sound and pressure stimuli often align with the plane of the superior canal (sorry, no blonde terminology for that one…that’s in the works). He and his colleagues published information about the syndrome and created a surgical procedure to correct the problem and relieve the symptoms. I don’t know him personally, but I’m going to go ahead and call Dr. Minor my homeboy.

The man that changed my life...Dr. Minor

I’m still trying to gain some answers myself as to what is happening in my head (aren’t we all?), but I tried my best to give you the information I have as of now. Feel free to contribute via the comment section with any questions or any information you might have about the diagnosis!