May 17, 2007
An Electromagnetic Mystery
Yesterday I arrived home from work in our new car. We struck a deal to have our old car bought back from us due to all of the problems that we have had (mostly weird electrical problems). In fact, it even died one last time at the dealership. When I arrived home, Greta and Irena were already feeding the babies. Greta mentioned that Niklas's fontanelle looked a bit concave again, and was concerned that the shunt may be over draining. I called neurosurgery, explained the situation and they instructed us to bring him into the ER. I thought to myself how weird it was that a piece of equipment in my son's brain may be failing and we both were calm as can be. This is our life now, and we have become very used to it, but I am not really sure how to feel about that.
First, let me explain how this shunt works. Niklas has a device that feeds a tube through his skull and into his ventricles which are filled with cerebral fluid. Since Niklas does not reabsorb this fluid well, it builds up in his ventricles causing pressure. When this pressure reaches a certain threshold, a valve opens and allows the fluid to drain down a tube that goes down the side of his head, his neck, and finally into his abdomen. The threshold at which the valve opens is adjustable externally via a magnet. They first use a tool which is similar to a compass in order to see what the setting is. The lower the setting, the easier the valve opens. They place the gauge on the side of his head to take a reading. When this device was first installed, it was set at 0.5. When this setting proved to be too low, it was then moved to 1.5 which seemed to be perfect. The threshold is adjusted with a very powerful magnet. According to the doctors, normal household magnets, speakers, and other electronic devices should not jump the setting.
When we were finally seen by our doctor, he pulled out the gauge to check where the setting was in case it had moved. Much to our surprise, the setting jumped back to 1.0. We really have no idea how this could have happened and are both praying that we don't have another defective piece of equipment. I asked the doctor if it was possible to purchase the device that checks the setting (not the device that adjusts it, but just the one that tells where the shunt is set). He informed us that it probably wasn't possible to buy. This morning, I called the manufacturer of the shunt to verify this and found out some interesting information.
It turns out that the both the device that checks the setting and the device that adjusts it are classified by the FDA as medical devices and so they can not be sold to consumers. The man on the phone expressed his disagreement with this. Why on earth would there be a reason not to equip every patient or parent with this device so that they can check the setting of their shunt? Luckily we are 10 minutes from the hospital, but what if we were not? Seems like checking the setting would be a good thing to do before rushing off to the hospital. Doesn't it seem logical that someone with this condition would wake up, take a shower, brush their teeth and check their shunt setting? It seems no different than a diabetic checking their insulin level. The man from Medtronic told me that there is litigation surrounding this. Not only that, but people are fighting to make the adjustment device available to patients as well. It seems as if adults with this shunt have claimed to feel good at a 1.0 setting one day, but on other days 1.5 might feel good. Think about it. Your level of hydration, barometric pressure, and sinus conditions could be different from day to day. Diabetics are able to control their insulin, why shouldn't a hyrdocephalic be able to control his cerebral pressure? Needless to say, Greta and I may try to purchase the equipment we need through our resources in Europe. In the end, every thing was fine and we both learned a lot. The first picture below is of the adjustment and measurement tools used to gauge the shunt. The second is a picture of the actual shunt.
Posted by Jason R. Myers