Thursday, February 2, 2017

Loose Craniocervical Fusion

So I have failed miserably at updating everyone recently! I had finals for school (which went very well!), family came in town for Thanksgiving, we went out of town for a friend's wedding and Christmas, and I had the stomach flu (TWICE).

So unfortunately I have some not so great news to update with. As I had updated a couple of months ago I have been having headaches since May of last year. They came on out of the blue and we were not sure why they developed or where they came from. Last I had left everyone we thought that my intracranial pressures (ICP) were high and were pursuing testing to determine whether or not venous stenting would be an option for me. This procedure would have been done if there was a venous abnormality present causing my ICP to be high. After having a special type of MRI done, called an MRV, to check my veins the vascular surgeon did not see any reason why my pressures would be high and saw no vascular abnormalities of any kind.

At this point we were left with two options. Go back to our original plan of pursuing more invasive testing of ICP or continue delving a little deeper to see if there was something else going on that we hadn't considered. Now this local neurosurgeon trained under my wonderful neurosurgeon, Dr. Rekate, in New York and is one of the only surgeons to perform both vascular surgeries and more traditional neurosurgeries. After he heard my neurological journey and symptoms through the past several years one point really stuck out to him: I had immense symptom reduction after my craniocervical fusion. Despite needing another neurosurgery (my tethered cord release) I was like a completely new person after my fusion. My symptoms were dramatically reduced and I was able to function again as a "normal" human being. I had no headaches after this surgery and my neurological symptoms like ringing in the ears, pins and needles, weakness in my limbs, and double vision almost completely disappeared too. With all this in mind this neurosurgeon decided that he wanted to run further tests to check on my fusion and ensure that it was still doing well. We thought that since I had such a sudden reemergence of symptoms that it was possible that something was wrong with my fusion.

The problem with this theory is that I have had numerous MRIs recently and they have all showed that my fusion looks great! The first and easiest test to check on my fusion was a flexion and extension x-ray. This is an x-ray taken with my neck bent all the way until my chin touches my chest and then another x-ray is taken with my neck bent backwards as far as it will go. The two images are then compared to determine whether or not there is a shift of the hardware of my fusion. Ideally no movement of the hardware should occur, which is exactly what we saw on the x-rays.
Now after the x-ray we were left with two more tests that we wanted to run. Thankfully we were able to have both of the scans done at the same time which helped to decrease the time we had to wait. The first scan we did was another MRI. The doctor wanted a special series of images on the MRI machine to view my venous structures in more detail. After reviewing this scan, he is even further convinced that I do not have any venous abnormalities and that that is something we can rule out.

Next, he wanted to have a CT scan done of my fusion to view it in greater detail. A CT scan takes a number of different x-rays taken at various angles and combines them together to form a computer generated image of the part of the body you want to see in greater detail. While MRIs are good to view soft tissue structures, like the brain and cartilage, it is not ideal for viewing my fusion because the metallic hardware shows up as bright spots on the images and can obscure the structures around it. The CT scan, on the other hand, is my better at showing us my fusion in detail because it shows the bony structures and the hardware is much clearer on this type of scan.

Thankfully this CT scan did provide us with some answers that we needed!

First, let’s start with a picture of what my hardware looks like:

(You are looking at the back of a skull and the first three cervical vertebrae of your spine)

This is the type of hardware that the new, local neurosurgeon uses, which is similar to, but not exactly the same as, what Dr. Rekate uses. I have screws (the larger purple pieces at the bottom of the piece of hardware) that go into the top cervical vertebrae, C1, as well as the second vertebrae, C2, as is shown in the picture. I also only have two screws (the small purple eyelets on the skull) in each side of the hardware that attaches to my skull instead of the three shown in the picture. Bone is supposed to form around the rods that go down from the skull to the cervical vertebrae, which further stabilizes the fusion and ensures the craniocervical joint is fully stabilized. Also, how fitting is it that my hardware will be purple?!?! For those who don't know purple is my absolute favorite color!

With that visual and explanation you can better understand what the results of the CT scan told us. The CT scan showed that on the right side all of the screws were firmly in place and that bone was formed completely and securely over the entire rod that goes down from my skull to my vertebrae. This side looks perfect and exactly what we would expect to see from a secure, solid fusion. The problem, however, occurs when we look at the left side of my hardware. The screws in my cervical vertebrae are solidly fused and secure, but the screws in my skull, on the other hand, are another story. These screws are fairly short, at only 6 mm long, which is about ¼ of an inch. These screws should be completely through the bone of my skull and the head should be flush with the bone. This is how they are on the right side, but on the left they are only 3mm in the bone. This means that they have loosened and are halfway out of the bone they should be in. In addition to this there is no bone formation on the rod as there should be. This means that the hardware is not solidly fused and the left side of the craniocervical junction is unstable.

We do not know why the fusion has failed on that side and the screws have come loose. I could have bumped my head and loosened the screws or they could have just wiggled loose over time. We believe that there was good bone formation initially, but for any number of reasons the bone has been reabsorbed (the body just breaks it down and metabolizes it) and the screws have wiggled loose and are not holding my skull securely to my spine anymore.

Now my symptoms are not presenting the same as they did when I needed my first fusion. The largest complaint I have had is headaches that are present on the top of my head. They feel like my head is going to burst and the pressure is incredibly intense. I have also had some blurry vision and ringing in the ears. These symptoms all lead us to think that I have pressure issues. The headaches and pain I had prior to my initial fusion were all in the back of my head, not up on the top and involved far more neck pain and discomfort. We are not 100% sure why my symptoms are presenting differently this time. There are a couple of guesses we have 1) my symptoms are not from the fusion becoming unstable and this is a completely separate issue to what is actually causing my symptoms (even if this is the case I still need to address the fusion not being solid because the loose screws in my skull are at risk for dislodging completely from the bone) 2) The nerves on the back of my head never regained function after my last surgery so I have a numb spot on my head. The symptoms that I previously felt on the back of my head may be being referred up towards the top of my head. 3) since the instability is isolated to a higher location, only my skull vs my skull and my vertebrae, and it is only on one side of my head I am feeling it differently than before. I do not have the neck pain and fatigue that I did before because half of my fusion is still solid and my brain stem is not being nearly as compressed as it was previously.

Given those thoughts we cannot know which is truly the reason for my new and differing symptoms. At this point we have to address the fusion being loose because like I stated before it is hazardous to leave loose screws in. My brainstem may also begin to be compressed again by the instability, which is not something we want to go through again. This will be addressed by performing a fusion revision. The hardware on my skull on the left will be removed and replaced with a new hardware and reconnected to the vertebral hardware. The vertebral hardware will not be touch and the right side won’t be touched wither.

The question of whether or not there are additional issues going on, specifically issues with my intracranial pressures, is something that we will have to table until after I heal from this fusion. If my symptoms are resolved after I have healed from the surgery we will know that the loose hardware was the cause, but if they do not then we will pursue further testing of my ICP. I will go into that more in another post, but unfortunately we cannot do the ICP test during this surgery and subsequent hospital stay as we are worried that the post-surgical pain I will be in will give us inaccurate numbers and thus cause the test to be invalid.

Well now that I have written you all a novel of an update I will write a subsequent post shortly with the information about the surgery and details pertaining to that for those that did not want to make it through my novel to just get the date and essential details! Thank you as always for all of your prayers and well wishes, they mean the world to my family and I!

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