Transcript of video:
The lining of the brain sits directly above the ear. Usually, there’s a firm barrier between the brain and the ear. Sometimes that bony barrier wears down. It can wear down either because you were born with a thin barrier or the constant pulsing of the brain above the ear can wear it down kind of like waves on a boulder by the ocean. If you come back after a week that boulder looks the same. If you come back after 10 years there’s a divot in that boulder from the waves of the ocean in the same way a thin bony barrier between the brain and the ear can be worn by constant pulsing or sometimes by trauma or chronic infections. What can happen then is some of the lining of the brain can actually dip down below into the ear or some of the fluid from the brain can actually dip into the ear or some of the actual brain can actually dip into the ear. When that happens, we call it an Encephalocele.
When it’s only the lining, we call it a Meningocele. When it’s both we call it a Meningoencephalocele.
On this diagram, you can see that there is typically a nice firm barrier between the brain and the ear. Underneath the brain is this honeycomb of bone called the mastoid and then further forward is the area where the ear bones are – the hammer and the anvil bone sit right under that lining. If this lining is thin for any of those reasons I discussed, the lining of the brain can actually sit right on the ear or right in the mastoid. That means that if you get an ear infection from a cold that the infection can actually use that as a path to go to your brain or to the fluid around the brain. That would be called meningitis as it infects the fluid around the brain or it can be an actual brain abscess or Encephalitis if it infects the brain tissue itself.
We have surgical strategies to repair when there’s a defect in that bone we call that bone the tegmen. Tegmen is Latin for “roof” so we’re talking about the roof over the mastoid or the roof over the middle ear. If there’s an opening, there are ways to fix that surgically. One way is to come from behind the ear if the defect is only in the honeycomb or the mastoid and in that case we can make a cut behind the ear, identify where that defect is and then repair that either with some of your own tissue or with a special bone cement to seal that up. If there is a lot of tissue going through that defect then we work together with the neurosurgeons and we make an opening right over that area gently elevate the lining around the brain and then place tissue and your own bone to repair that opening. We don’t leave a soft spot, though – we replace where we took that bone for the repair with a special mesh made out of a titanium metal. That titanium is actually stronger than your own bone but it won’t set off any metal detectors.
The surgery we’re talking about usually lasts about an hour or so if we’re able to repair it just by coming from behind the ear you get to go home the same day. If we actually have to elevate the lining of the brain, we’ll keep you overnight in the Intensive Care Unit because one of the things you worry about whenever you have to elevate the lining of the brain is the possibility of bleeding or issues like that. But this has been a very safe procedure that has been very effective at sealing that barrier, preventing leakage of fluid from around the brain into the ear and more importantly, preventing infection from making its way from the ear in towards the brain.