Hi I am Dr. Amber Luong I'm an associate professor here at the University of
Texas Medical School within the Department of Otolaryngology. What I
wanted to talk to you about today is a cerebral spinal fluid leak or more
more commonly called brain fluid leak and the reason why I wanted
to talk to you about this is because of the fact that this can often be mistaken
for allergies and it's something that I think that the patients often know
better than the physician that there's something not quite right. So what
exactly is cerebrospinal fluid leak or we'll call it a CSF leak or brain fluid
leak. Basically it's when you notice clear fluid leaking out of your nose. The
reason why patients often know that it's not quite right or it's not allergies is
that it's very different from allergies and the fact that the clear liquid often
comes more from one side versus the other so rather than in allergies where
you feel drainage on both sides, brain fluid leak or cerebral spinal fluid leak
is often only on one side. What's really interesting about CSF leaks is that you
can prompt it or you can get it to start leaking when you lean over so a patient
will describe leaning forward and having it drip either on the right side or the
left side. If by chance it happens to go to the back of your throat you may
notice a slightly metallic, salty taste to it. And so if you have those symptoms
I think that's when you should start asking your doctor or thinking about the
potential brain fluid leak. So brain fluid leaks are not very common, in fact
they're not they're not very common in general however I get to see a lot of
these because I'm over here at the Medical Center and a lot of these types
of diagnoses get referred to me. I'm a sinus surgeon that does sinus surgery as
well as skull base surgery and that's working on the area of the bone that
separates the brain from the sinuses. So when you suspect a brain
fluid leak, when should you be worried about it or when do we start
worrying about it? Well, there's pretty much three typical
causes for brain fluid leak. The most common cause I think almost over 90% of
these brain fluid leaks happen after some sort of trauma, some sort of
accident a car accident or other accidents and it may happen immediately
or it can happen several days to even a couple weeks to months after a an
accident to the head. In that situation if that is the cause or thought to be
the cause oftentimes these are treated with just a lumbar drain or a drain
that's put into the back of your spine and this takes some of the fluid off of
the back to minimize the pressure on the site where it's leaking from and
allowing it to heal. This may be about three to five days where the lumbar
drain is placed and that often is all that's required for that treatment. The
other possible cause is after some sort of a tumor. So a tumor in the brain or in
the sinuses can then grow and cause a hole in that skull base the one that's
separating the brain from the sinuses and in that situation the key is
that we need to know that we need to treat that tumor and then ultimately
that defect can be repaired surgically. The one that's really difficult to
diagnose and the one where you'll probably be involved most in helping us
make that diagnosis is the ones that happen spontaneously. The spontaneous
ones are where you don't have a history of a tumor, you are not diagnosed with a
tumor, you have no history of an accident. The other cause that I forgot
to mention is if you've had a prior sinus surgery or some sort of surgery
done on the brain sinus area that surgery can potential complication
is a defect in that skull base causing a CSF leak but if you don't have those
situations then there is a entity or a diagnosis where it's a spontaneous CSF
leak. So a spontaneous CSF leak it happens because we don't know what the cause is,
but what we believe is going on is that for whatever reason you have an
increased intracranial pressure on the brain fluid. I should back up a little
bit to give you a little bit of the anatomy. So the brain fluid is the fluid
that surrounds the brain but the fluid and the brain is covered by lining
called the dura and then that of course all lives inside your your skull and
separating the brain from the sinuses is this skull base. So in a spontaneous CSF
leak there is whatever reason increased pressure in on the brain fluid and
over time and this may be months - maybe even years we believe this pressure
thins out that bone that separates the brain from the sinuses and it eventually
breaks through and creates a hole or a defect and then once that defect is
there then the brain fluid can then leak into the sinuses ultimately into the
nose where you'll you'll detect it. And so those are the most common and again
the one that I failed to talk about was if you have a history of having some
sort of sinus surgery or surgery done into your nose or even brain surgery
sometimes there may have been a defect or a hole that was either undetected or
not noticed at the time of surgery that then can cause a CSF leak. So what do you
do or what does a physician do when they suspect this? Well, first of all the
history and physical or the history is very important so as I mentioned leaking
primarily from one side that doesn't respond to allergies because oftentimes
we as physicians think that it's ours because it's more common and if it
doesn't respond then we start thinking about maybe a CSF leak or something else
that's going on, we'll try to collect the fluid in the clinic. The fluid is
collected so that we can look for whether or not this fluid is in fact
brain fluid. What we can look for is a protein called beta - transferrin so
we'll collect the fluid or have you collect the fluid for us send it off to
the lab for beta to transferrin if it is in fact positive then it is most likely
brain fluid leaking from your nose. Now the second
step will be to try to figure out exactly where it is leaking from. In
order to do that we get imaging studies. So imaging studies usually consist of a
CT scan of the sinuses or head as well as an MRI. The CT scan allows us to find
the bone defect, so CT scans are very good at looking at the bone structure of
the area. Why do we get an MRI? Well sometimes when you have a hole in your
skull base the if the hole is big enough sometimes parts of the brain can pooch
out into this defect and we want to know that prior to considering any sort of
surgical repair. So we get both the brain CT as well as the brain MRI
looking for this pooching also called an encephalocele. So once we know that the
cause, if it is spontaneous, and we know where it's leaking from and we've
confirmed that is in fact brain fluids that's leaking then the most common
treatment is a surgical repair. These days oftentimes this surgical repair can
all be done through their nose so you don't have to have any incisions on your
face or on your brain which is a huge improvement from about 20 years ago.
The surgery involves putting a camera into the nose and basically opening up
the sinuses so that we can see where on the skull base where this hole is and
then with the help of a camera we can then visualize where the actual leak is
coming from. So how do we tell where the leak is coming from? Well when you're in
with your ear nose and throat doctor or a rhinologist, one of the referrals or
other doctors that we'll have you go see is a neurosurgeon the neurosurgeon will
help us put in a lumbar drain at the time of surgery. Again that's that drain
that goes into the into your back and what that allows us to do at the time of
surgery is to take a little bit of your brain fluid and put some dye into it: a
yellow bright dye that we put into it and then we put it back into your spinal
fluid and this then of course circulates around the
brain and so now at the time of surgery that dye highlights where
the leak is coming from. So this allows us to not only confirm that on the CT
scan where we think the leak is coming from we can actually see the leak and
this will also help us with our repair to make sure that we can confirm that
there's no further leaking. So what we do is once we can see it with the camera
and we can see where the defect is we basically expose the defect and after
that it's just a matter of plugging it up. So what are the things that we use to
plug up this hole? Well we can borrow some tissue from the lining of the
inside of your nose to plug it up. We sometimes may need to use fat from your
abdomen to just kind of plug up the hole especially when it's really
small or in an area that's very difficult to get to or we can sometimes
use synthetic material that's safe to be put next to the brain. If the hole is
very big we may have to put several layers in it, several layers between the
brain and the bone and then the bone within the sinuses but once we have all
those layers in place and we confirm with our dye that there's no further
leaking then we put some additional packing on the inside of your nose to
kind of support that repair. Often times you'll have to be admitted to the
hospital somewhere between one to three days after your surgery with that lumbar
drain still in your back. Over the time that lumbar drain is to kind of take off
a little bit of the brain fluid so that it minimizes the pressure just to help
with the healing process and to allow this area to heal somewhere between one
to three days the lumbar drain will be kept in place. After that the drain will
be taken out and then you'll be allowed to go home. Probably for the next four to
six weeks we'd ask you to kind of minimize activity, take it easy,
try not to exert yourself too much. Again we're just trying to minimize the
pressure in your brain to help allow that area to heal.
And then at that point you'll keep seeing your ENT surgeon back for
some routine follow-up just to make sure that everything is healing properly. If
taken care of properly there should be no problems and
oftentimes this heals without any issues and you don't require any additional
surgery. In some situations people who have these spontaneous leaks they have
this condition that causes their pressure on their brain to be higher
than normal and so you may have a couple of holes in your skull base or a couple
of areas that are weak and at the time of surgery maybe there was only one area
that's actively leaking but it is possible that over time there may be
other areas that may leak. If that happens then we may have to go in and do
basically the same surgery on that other spot that's leaking. That's very rare but
if it does happen we basically go in the same way and repair it. Now if it happens
for the third time we may need to ask our neurosurgery colleagues to consider
some sort of permanent way of decreasing the pressure off that brain. If you're
concerned about this, about a brain fluid leak, for either you or your family or
just want to learn a little bit more please feel free to give us a
call at the University of Texas physicians the Department of
Otolaryngology. We work hand-in-hand with our neurosurgical colleagues as well as
our surgical team Memorial Hermann Texas Medical Center where these repairs are
done on a pretty regular basis
UT Physicians A part of UTHealth Memorial Hermann Texas Medical Center