My friend Josh works with MRI (magnetic resonance imaging) data as part of his research. He offered to scan my brain while I'm visiting him here in San Diego. Of course I said yes. So yesterday, we went to visit the new 3.0 Tesla machine and I went inside it with a mixture of curiosity and fear.
In the antechamber/control room, I dumped all my stuff and removed my belt, my ring and my shoes. It felt a little like preparing to go through airport security. We briefly discussed whether or not I should remove my tongue ring. Since my tongue heals very quickly, I decided to leave it in, even though it would make the 3D reconstructions look slightly weird because my mouth would drop out. You can see this effect in the images below. I put in the fluorescent yellow disposable earplugs and Josh led me into the MRI room.
The MRI room is cold and filled with the thunking of mechanical pumps. I lay down on the scanner bed with my arms at my sides, feeling a bit like River Tam in Firefly. Josh arranged a blanket over me and gave me a squeeze ball so that I could let him know if I felt claustrophobic at any point. He would stop the scan and let me out if I didn't want to continue. He positioned my head under the headrest, which is equipped with a mirror so I had a rather dizzying inverted view of the room. The faceguard made me feel like Hannibal Lechter. He also supplied me with headphones, so he could talk to me between the scans. These also provided additional buffering from the noise of the scanner. Finally, he aligned the scanner with my head (with a laser! OK, only a weak HeNe, but it was still a laser) before the bed slid into the scanner headfirst. If you ever do this yourself, I advise not looking in the inverted mirror while the bed is moving. Bleurgh.
A scan is actually composed of several separate scans, which Josh kindly talked me through. The first lasted only 13 seconds, but gave me a feel for just how loud the machine is. It's LOUD. I don't understand how anyone sleeps through it. The second scan was over eight minutes long and the third and fourth were both four minutes long. I kept my eyes closed and breathed deeply, using the powernoise rhythm (ka-THUNK-chk, ka-THUNK-chk) of the machine to time my breath and try to stay still. I couldn't help tracking the sounds of the scanner with my eyes so there is some slight blurring around them in the images.
The above is a mid-sagittal cut through my brain, so it's positioned right between the two halves of my cerebrum.
Happily, it appears that my brain is quite normal. Lots of grey matter nicely bathed in cerebrospinal fluid, healthy ventricles, no tumours.
I searched for the dropout in the "remember to bring pants" region, but the resolution wasn't high enough to see it.