When Size Doesn't Matter (But Your Symptoms Do)

Let’s Talk About Chiari Malformation

By Antonia @ Unremarkable Me

If you’re reading this, there’s a good chance you’ve already ridden the NHS medical merry-go-round and landed in a particularly frustrating spot: your body’s screaming, but your scans are whispering, “Nope, nothing to see here.”

Welcome to the bizarre world of Chiari Malformation—where millimeters matter, unless, inconveniently, they don’t.

So... What Is Chiari Malformation?

Chiari Malformation (CM) is what happens when your cerebellar tonsils—the little bits at the bottom of your brain—decide to pack their bags and migrate south through your skull into the spinal canal. This causes a cerebrospinal fluid (CSF) traffic jam. Picture the M25 at rush hour, but inside your head. Delightful.

Technically, Chiari Type I is diagnosed when the tonsils dip 5mm or more below the foramen magnum (that big hole at the base of your skull). But spoiler alert: the “5mm rule” is about as reliable as a Southern Rail timetable during leaf season.

Why Size Doesn’t Always Matter

Here’s the kicker: some people have a 3mm descent and feel like they’ve been hit by a neurological freight train—headaches, dizziness, numbness, balance issues, the works. Meanwhile, others have a 12mm drop and are off hiking Ben Nevis.

It’s not just anecdotal, either. According to NORD, some patients show all the symptoms with no measurable herniation at all (a.k.a. Chiari 0). A Medscape overview backs this up—tonsil position doesn't always correlate with symptom severity.

Translation? Your brain’s not reading the rulebook. It’s freestyling. Poorly.

The NHS Approach: “Watch and Wait” (Forever, Potentially)

If you’re in the UK, chances are you’ve heard this classic:“Let’s monitor it for now.”Roughly translated: “Unless your head falls off, we’re not keen on surgery.”

Now don’t get me wrong—I love the NHS. But when it comes to Chiari, “conservative management” often feels less like caution and more like politely ignoring a house fire.

NHS guidelines recommend avoiding surgery unless your symptoms seriously affect your life or worsen. You’ll usually start with painkillers and life hacks like “don’t cough too hard”—which is just chef’s kiss useful during flu season.

Surgery—typically cranio-cervical decompression—is held back for the “really bad” cases. Which is great, unless you’re living in the grey zone of “pretty awful but not dramatic enough to count.”

Is “Wait and See” Actually... Harmful?

Here’s where it gets murky. A PMC study found that some patients do remain stable without surgery. But others—especially those with cough headaches—can deteriorate if left untreated.

Another study linked delays in surgery to more complex outcomes. So it’s kind of like playing healthcare roulette: will today be “stable,” or will your symptoms level up like a bad boss fight?

What Can You Actually Do?

If your scans look “fine” but your body disagrees, here’s your plan of attack:

• Document everything: Symptoms, triggers, daily impacts, how it’s affecting your life.

• Push for a referral: A neurosurgeon or Chiari-literate neurologist is key. Not just any consultant.

• Get a second opinion: Especially if you’ve been dismissed. (Bonus points if you do it with passive-aggressive tea-drinking.)

• Use the research: Bring studies. Quote NORD. Go full Hermione Granger, if needed.

  
  

Final Thoughts (and a Pinch of Hope)

Chiari Malformation is messy. It doesn’t always show up on scans the way doctors expect, and treatment pathways—especially in the UK—don’t always match the lived reality of being symptomatic without textbook herniation.

And while “watch and wait” sounds sensible in theory, for many patients it becomes “watch and worsen.” The risk of under-treating is just as real as the risks of surgery.

So advocate. Speak up. Challenge assumptions. You’re not making it up. Your symptoms are real—even if your scans, or the NHS, haven’t caught up yet.

Further Reading & Resources(aka, Your Hermione Ammo)

• NHS Overview: Chiari Malformation

• NORD: Rare Disease Info on Chiari

• Medscape: Chiari 101

• PMC: Natural History of Chiari

• PubMed: Symptom-Surgery Study

• PMC: Timing and Surgical Complications

  
  

Stay strong, stay loud, and remember: Millimeters don’t define your pain. But your voice just might change everything.

Love,Unremarkable Me