Tethered spinal cord diagnostic imaging

Hi everyone,

I am wondering what kind of MRI is needed to diagnose tethered spinal cord. I had surgery in October, 2021…actually, 3 surgeries, but long story short, I ended up with a VP shunt for Chiari malformation secondary to hydrocephalus (secondary to aqueductal stenosis). My herniation went from 12 mm to 5 mm, and the horrendous headaches went away, but since surgery I have been having progressive low back and right leg pain.

It was first diagnosed as sciatica and I was referred to physical therapy. This did not help and my pain became worse and worse. I finally convinced the doctor to order an MRI. I have some minimal disc herniations, but my doc says these are not severe enough to cause the kind of pain I’m having.

And then he left the appointment and pronounced the case closed. I saw another doctor and got MRIs of my brain, C spine, and thoracic spine. Still no answers. No syrinx, no significantly herniated discs.

Now I’m wondering if I have a tethered cord that did not show up on my lumbar MRI. Since my shunt alleviated the downward pressure on my brainstem and spinal cord, is there now traction on my filum terminale that is causing this horrible pain? My conus medullaris is at the level of L1. Could it have been lower prior to getting my shunt?

I have an appointment with my PCP to discuss all of this, and also an appt with neurology coming up. But I want to know my stuff prior to going in, so that I know what to ask for (you know how doctors are).

My question is, what imaging is needed to diagnose tethered spinal cord. Do I need a prone MRI? Sacral spine imaging?

Hey Amy,
I too have a VP shunt and I’ve had some awful issues with it all. When it was first ‘installed’ I was having some horrible symptoms ‘Ohh, you’ll just have to get use to it… …it’ll settle’ Only it didn’t. Every time I raised an issue it was minimised. “The shunt has reduced the pressure and the shunt is working…’ and it was true, the shunt had reduced the pressure, but the cause of the pressure building in the first place was still present and hadn’t been dealt with.
The did an ‘Enhanced’ CT scan and sure enough, right in the middle of my brain is this growth. Prior to them being able to see the thing on a scan I was repeatedly told 'They operated, they fixed”. I’d told them time and again ‘Something just is not right’ and was made out to be every type of crazy, but when they could see it, it was like “Ohh look what we found…”

ICP (Intracranial Pressure) can play some weird and wonderful tricks on the mind and body which can be difficult for us, ourselves, to interpret and comprehend. To then have a medico discredit out concerns… infuriating. I too went looking for answers of why my pain/sensations were not settling, but I didn’t find any great answers. I think the closest I came to ‘an answer’ was from an ophthalmologist “well, you’ve had brain surgery… …what did you expect?” What I didn’t expect was ‘THIS’, battling to manage day to day.

As for which scan. MRI scanners are rated by a (T) rating the ‘T’ meaning Tesla. To see the fluid motion and separation between CSF and blood flow it is my understanding that a 3T scan with enhancing would be required.
Now, I have to say here, I am not a Dr, merely a patient and this is all something that would need to be discussed with a fully qualified neurologist and possible a neurosurgeon to obtain a full and comprehensive diagnosis.

Hope it helps
Merl from the Modsupport Team

Hi Merl,
Thank you for your response. I have learned to not blindly trust the doctors, especially where my ICP is concerned. I almost died three times while in the hospital because they kept clamping my EVD (this was after the failed endoscopic third ventriculostomy surgery and before they gave up and installed a shunt). There was CSF leaking out around the clamped drain (my hair was dripping fluid) and they still pulled out the drain and sent me to the neuro floor. I lost consciousness and the neurosurgeon on call that night had the pleasure of doing emergency surgery to place a new drain.

My latest head MRI showed slit ventricles, and then of course artifact in the posterior where my shunt valve is located. So I have no imaging of my cerebellum or brainstem. Also of note is superficial siderosis (I had bleeding into my ventricles from the first surgery) and encephalomalacia in my thalamus where my stroke was.

I have appointments lined up with every doctor I can think of: my PCP on Monday, then in June, neurology and neurosurgery (I had to fight to get a different surgeon from the one who operated on me and caused my stroke. I think it’s a huge conflict of interest for him to review my scans when my pain issues may have been caused by his surgery).

Another shunt question: after my 3 stat MRIs to diagnose my pain, I walked into the neurosurgery office for a quick shunt check (the neurosurgery PA who checked it last time said I could always do this, no need for an appointment if I was worried). The MAs were horribly rude and told me I would have to wait until tomorrow because “no one who knows your case is in today”. Half of their surgeons had either operated on me or rounded while I was in the hospital. They didn’t want to bother the surgeons. They repeatedly told me to go home and return the next day. I explained over and over again that I was afraid I would not wake up in the morning if my shunt was improperly set (it’s on a high setting). It took forever for them to call an NP out of surgery to check my shunt. It took her two minutes to do the check (it WAS on the wrong setting). She was annoyed and told me I would have been fine for 72 hours. On my way out, I saw two surgeons sitting at computers, including the one who placed my shunt. Was I so wrong to demand a shunt check? I think they were being blasé about my life to keep telling me to go home, especially when it’s so quick and easy to check a shunt setting.

Hey Amy,

Ohh yes. this is a battle I too have had. The medicos all refer back to the original surgeon who says ‘All Fixed’. If this was ‘All Fixed’ then why am I so symptomatic? When I asked this question the reaction was not good, in fact the dr’s put it all back on me like I choose to be in agony, so it must be a psych issue or my favourite diagnosis ‘Idiopathic in nature’ or ‘There is no cause’. They have repeatedly (x6) chopped my head open and ‘There is no cause’??? If this was all imaginary I should be able to imagine it all away. Well, don’t I wish.

Yes again. After the 5th operation the attitude I got was ‘We operated, we fixed’ but if this is fixed I can think of another ‘F’ word that better describes my situation, so I ignored my symptoms and tried to get on with ‘life’. But my symptoms were progressively getting worse (and worse), something wasn’t right. I eventually got an appointment with the surgeon and he was furious, turns out there was an issue, I too had slit ventricle syndrome and they established that the shunt valve was faulty, draining too much fluid. I was operated on again having the entire shunt train replaced, leaving the old shunt tubing within my skull in situ. So now we have more questions (without answers). Is the cause the defunct shunt? Is the cause the new shunt? or (the easiest answer for the medicos) Is it all ‘Idiopathic in nature’? And even years later those questions still get thrown around (without answers).

Again, I agree, but the medicos HATE and I mean really HATE having ‘conflicts of interest’ or ‘duty of care’ being identified. When I brought these scenarios to their attention I was accused of attempting to obtain financial gain by suing them. I had/have no intent of suing. I’m looking for answers, not $$$$. The way I look at it is if they didn’t operate I’d be dead, but how do I best manage it all. Their attitude is ‘Well, don’t be blaming us… …it must just be YOU!!!’ Like this is a choice thing. GGrrrrr and then they wonder why I’m so frustrated. ‘Ohh, frustration… …ohhh, that’s a psychological issue’ OHH BROTHER.

NO. In fact I would have thought that should have been one of the primary checks. You have a plastic ‘appliance’ within your skull. Unlike other bodily systems which can naturally adjust, the appliance cannot. So if there is an issue that should be the first ‘red flag’ to be investigated, but then maybe I’m being just too simplistic, “…the dr ALWAYS knows best…” or so they reckon.

Merl from the Modsupport Team

Sorry if this is duplicated, but in editing my 1st post, it appeared to disappear?

Haven’t had any surgery (yet), but have some similar issues as you with a slightly different history - a very LSS: cough headaches followed by a CM diagnosis; symptoms mostly went away on their own (along w/some weight loss) when I too had bad sciatica symptoms with great relief immediately after a lumbar pain injection only for CM headaches (+ dizziness) to return w/vengeance shortly thereafter with a followup MRI that showed my CM had progressed.

Consults w/2 surgeons (that I liked/respect) w/2 different opinions: 1 a tethered cord might play a role in CM and CM/symptoms, but w/o MRI confirmation, I don’t have a tethered cord; 2: based on a variety of hands on tests (positional numbness in feet, etc) I likely have a tethered cord, but it plays no role in my CM, and I need to address my CM 1st. Both also disagreed on the idea that I might have a CSF leak, but I had a blood patch ‘in case’ w/o any improvement. Note:am also dealing w possible ICP (later MRI showed increased space above cerebellum) w/both Drs mentioning a shunt option but no certainty there.
Again, LSS - I’m been seeking a 3rd opinion from a CM/TC surgeon with extensive adult TC experience (the process has been unbelievably long and strange for reasons that I can’t figure out) but in order to have to best/most current records (if/when an appointment happens), I recently had a T3 MRI lumbar done that according to the radiologist, indicated no signs of TC.

Some reputable surgeons believe that an adult TC can exist w/o MRI confirmation as long as there is some hands-on diagnostic confirmation. A T3 MRI could confirm a TC (was surprised to find out a T3 wasn’t that much more expensive than a T1.5) but it may not rule it out.
In my layman mind, I would think a decompression might alleviate some sciatica symptoms (at least in the short term) but the spine is complex w/lots of conflicting opinions, so I may be WAY off on that. To manage my sciatica (nowhere near as bad as before the shot) I am doing some very strict dura-glides that strangely seem to ‘maybe’ be helping my headaches and ever so slightly my sciatica (could be placebo) but at least isn’t making things worse. I was of the opinion that given my CM, any PT is to be avoided but found a PT+(knowledge of CM better than most doctors) that is not making me worse.
Sorry for the book - hope it helps some.