What the three scans at a first visit actually measure

A first visit here includes three scans. They take a few minutes, none of them touch you with anything sharp, and you stay fully clothed for all three.

People usually ask what they are for. The honest answer is narrower and duller than the answer some practices give, so it is worth setting out plainly.

The problem they solve

How you feel on a given morning moves around a great deal.

You slept badly. It rained. It is a Tuesday and you have a meeting you are dreading. Any of those can change what your body reports to you, and none of them have much to do with what is going on structurally. So if the only measure of progress is what you say when asked how you are doing, you and I are both guessing, and we are guessing from a noisy signal.

The scans exist to give us something that does not move around as much. We run them the same way each time, with the same equipment, in the same room. Six months from now there is a consistent record to compare against rather than two people trying to remember what March felt like.

That is the whole purpose. They are a record, not a verdict.

Surface EMG

Surface electromyography reads electrical activity in the muscles alongside the spine. Small sensors rest on the skin. Nothing is inserted and nothing is injected.

Muscles produce a small electrical signal when they are working. The instrument records how much signal is present at various points up and down the back, and whether the left and right sides are producing similar amounts.

[TODD — which unit do you use, and roughly how long does the pass take?]

Thermal

The thermal scan compares skin temperature on the left and right side of the spine at the same height.

Temperature at the surface is influenced by blood flow, which is regulated in part by the autonomic nervous system. So the instrument is reading a downstream consequence of something else. The comparison that matters is left against right at the same level, rather than whether any single reading is high or low.

It is a contact thermometer run down the back. There is no radiation and no imaging of any kind. It is not an X-ray, and it produces no picture of the inside of you.

Heart rate variability

Heart rate variability is the variation in time between one heartbeat and the next.

A heart does not beat like a metronome. The gaps between beats vary slightly, and how much they vary is influenced by the autonomic nervous system. Measuring it is a matter of recording a few minutes of heartbeat timing accurately and doing arithmetic on the intervals.

[TODD — do you take this sitting or lying, and for how long?]

HRV has become popular enough that many people arrive already tracking it on a watch. The reading here is taken under controlled conditions, which is what makes it comparable to the next one, and to the one after that.

What these are not

This is the part most worth reading.

They are not diagnostic tests. They do not identify disease, and they are not a substitute for the tests your physician would order. If something needs a medical diagnosis, it needs a physician, and we will say so.

They are not imaging. No X-ray, no MRI, no picture of your anatomy. If imaging is warranted, that is a referral, not something we do here.

A number moving is not proof of anything on its own. Readings shift for many reasons, including the room, the time of day, what you did that morning, and ordinary variation. A single scan compared against a single later scan tells you very little. A consistent record over many months, read alongside how you are actually doing, is worth something.

They are not required. If you would rather skip them, say so. It changes nothing about whether you can be seen here.

Can I have my numbers?

Yes. Ask and we will print them or go through them on screen with you. It is your body and your record.

If a scan raises a question that belongs with a physician, we will tell you that too, and we would rather tell you early than not at all.