Why image guidance matters for headache injections

If you have had an injection for headache that did not help, the first question is not whether the treatment works. It is whether the needle got where it was meant to go.

Every injection at this clinic is placed under ultrasound or fluoroscopic guidance. Not as an upgrade, not on request — as the default.

Three separate reasons

It works more often

Placed by surface landmarks — feeling for a bony prominence and estimating the rest — the needle goes where the anatomy is usually found. Anatomy varies between people. If the medication does not reach the target, the block fails for a reason that has nothing to do with whether the treatment is effective.

It is safer

Around the head and neck, the structures you are avoiding sit millimeters from the ones you are aiming at. The occipital artery runs alongside the occipital nerve. The stellate ganglion sits among the carotid artery, the internal jugular vein, the vertebral artery, the thyroid and the esophagus. The atlanto-axial joint is adjacent to the vertebral artery and the C2 nerve root, with the spinal cord millimeters away.

A landmark technique cannot see any of them. Ultrasound shows vessels and soft tissue in real time, with Doppler to confirm which is which. Fluoroscopy shows the needle against bone from multiple angles, and contrast injected first confirms both that the medication will reach the target and that the needle has not entered a vessel.

A negative result becomes trustworthy

This is the one people do not think about, and it may be the most valuable. A great deal of headache diagnosis rests on diagnostic blocks — ICHD-3 accepts abolition of the headache by diagnostic blockade as evidence that a cervical structure is the cause.¹

That logic only holds if you know the block reached its target. An unguided block that fails is uninterpretable: it may have missed. A guided block that fails tells you the pain is arising somewhere else, which is real information you can act on. See do nerve blocks for headache actually work.

Which technique, and why

Ultrasound

Real-time soft-tissue imaging, no radiation. Used for the stellate ganglion block, for occipital nerve blocks, and for the superficial trigeminal branches. The needle is watched moving through tissue as it advances.

Fluoroscopy

Live X-ray, for targets defined by bone. Used for the atlanto-axial (C1–C2) injection, for cervical facet and medial branch work, and for deeper trigeminal approaches. Contrast is injected first and watched as it spreads.

What it means for you

Practically: a procedure that takes a few minutes longer, and a result you can rely on either way.

If you have had an injection elsewhere that did not help, it is worth finding out whether it was image guided. A repeat of the same block done properly is a different test, not a repeat. See ultrasound and fluoroscopic guidance.

Common questions

Does image guidance make the injection hurt more?

No. Ultrasound adds a probe on the skin and nothing else. Fluoroscopy adds positioning time. Neither adds pain, and better placement often means less discomfort. See image guidance.

Is the radiation from fluoroscopy a concern?

Exposure for a single targeted injection is low and used only where bony landmarks require it. Where ultrasound can do the job, we use ultrasound and there is no radiation at all. See image guidance.

How do I ask whether my previous injection was guided?

Ask directly whether ultrasound or fluoroscopy was used, and whether contrast was injected. If neither was, a failed result does not tell you the treatment was wrong for you. See contact us.

Are some injections safe without guidance?

Some superficial blocks are routinely done by landmarks. But the ones we do around the neck — stellate ganglion and atlanto-axial in particular — are not among them, and we do not perform those blind. See atlanto-axial injection.

Sources

1. Headache Classification Committee of the International Headache Society. ICHD-3, 11.2.1 Cervicogenic headache. ichd-3.org