I’ve seen a lot of questions about gentamicin injections lately,
so here is little summary of my take on them.
Here is my post on my PERSONAL experience with them and how I'm doing today in 2015:
http://menieresandme.blogspot.com/2015/04/update-on-me-and-menieres-in-early-2015.html
http://menieresandme.blogspot.com/2015/04/update-on-me-and-menieres-in-early-2015.html
I also highly recommend Dr Timothy Hain’s page on gent
injections at:
These comments are primarily directed at the UNILATERAL patient (having Menire's in only one ear). Bilateral patients may need gent injections at some point, but it will be a different calculus on how/when.
Attached is picture of my "ladder of treatment" for unilateral MD - you can see gent is a few steps UP the ladder.
Gentamicin injections are intended to literally and
purposefully DESTROY the function of your balance organ in your inner ear. Imagine a “balance function” dial. Well, the injections are intended to turn
that dial down so that ear doesn’t send balance function signals to your brain
as much or as strongly anymore. Why
would we do this? Well, in unilateral
Meniere’s Disease patients (in only one ear), the vertigo attacks are caused by
the balance organ in your affected ear sending “bad” balance signals to your
brain. Your brain becomes confused at
the fact that your good ear says you are sitting in a chair and your “bad” ear
is saying you are moving in circles or upside down, or sideways. The brain can’t decide what is going on so it
loses control of your eyes and you have what is called Nystagmus - your eyes
jerk back and forth uncontrollably. This
results in the sensation of rotational vertigo that is so debilitating to the
patient.
The injections are intended to make those bad signals from
that ear quieter or make them stop all together. Our brains CAN AND WILL learn to listen to
only our good ears. It may result in less intense and more manageable attacks or if you have enough of them almost no attacks at all (but also no balance function left in that ear).
Thanks to the disorder along with a gent injection my "bad ear" only has about 4% balance function left. My other ear is normal (I am lucky so far!). At this point my brain has learned to ONLY listen to my good for balance, partially thanks to physical therapy (see below). When I do have attacks my balance organ in my bad ear barely registers them and they affect me very very lightly. If my good ear started to become affected, I'd have to deal with that, but for now I am very stable and am actually thankful that bad ear's balance function has been "turned off".
Thanks to the disorder along with a gent injection my "bad ear" only has about 4% balance function left. My other ear is normal (I am lucky so far!). At this point my brain has learned to ONLY listen to my good for balance, partially thanks to physical therapy (see below). When I do have attacks my balance organ in my bad ear barely registers them and they affect me very very lightly. If my good ear started to become affected, I'd have to deal with that, but for now I am very stable and am actually thankful that bad ear's balance function has been "turned off".
However, when we aren’t having attacks are “bad” ear can
still send good signals to our brain. So
in between attacks the brain is happy with both ears. When you have a gent injection it turns down
the balance function all the time - so even if you aren’t having vertigo, after
the injection you will have less function and your brain will be confused as it
adjusts to this new reality of balance signals from your bad ear. (PS the
disease itself can also reduce balance function through attacks). After your balance function has been reduced
you will feel unsteady and need time to have your brain adjust.
It is imperative
after gent injections you do vestibular rehabilitation physical therapy
exercises at home or with a professional to help push your brain to compensate
and listen more to your good ear. Your balance has been reduced permanently on one side, the brain NEEDS help. These
exercises will be uncomfortable, it will push you, you may sweat or feel dizzy
while doing them. That is SUPPOSED TO
HAPPEN. The more you push and practice
and help your brain retrain your eyes and ear the better you’ll feel a few
weeks or months down the road. If you lie
in bed or avoid things or avoid leaving the house, or doing the exercises your
brain will take much longer to compensate, or never will and you will not reach
the point of better compensation.
Usually gent injections are provided in a low dose series with
time in between to better help you manage and compensate from the balance
reduction each time.
How many shots does it take? One gent injection will likely not "do the trick" alone if you have a high amount of balance function left in your Meniere's ear. It is important to remember the goal of gent injections (which is VERY different than steroid injections) - we are literally destroying your balance organ function in the ear getting the injections so it will stop sending problem balance signals to your brain. Sometimes the function must be taken almost to zero in order to make the bad signals stop. This treatment is usually primarily advocated in patients are NOT bilateral and have one ear that is normal and has remained normal for some time.
The brain can and WILL learn to listen to only the good ear if balance is "turned off" in the bad ear. One low dose injection may take you from say, 85% function to 70% function (confirmed via VNG/ENG). 70% function for some people is still enough for you to feel a Meniere's attack and have that ear cause vertigo. For reasons not understood fully one injection may be enough for some folks. But for others additional injections may be necessary to bring the ear down to say, 25% or even 10% or less before the ear "shuts up" and leaves your brain alone and the vertigo attacks stop. This is my situation as my "bad ear " has only 5% or so balance function left and so my vertigo attacks have stopped. My brain can't "hear" them when my ear is being symptomatic. I still have Meniere's attacks (I have fullness, tinnitus and very slight dizziness) but the full on bad balance signals don't get through.
If I were go to bilateral... well, I'd have to deal with that and I likely couldn't get gent injections in my other ear. I'm 14 years in and I'm not bilateral so far, and hope to stay that way, but that doesn't always work out. So gent is a risk (in as much as you may become bilateral) but it can be a risk worth taking.
If the injections don’t work to fully reduce symptoms to a
manageable point, the Dr may suggest just removing the organ all together
(labyrnthectomy) or severing the nerve that carries balance messages from that
ear to the brain (vestibular nerve section).
Traditional "ladder of treament" for unilateral Meniere's Disease (image):
Traditional "ladder of treament" for unilateral Meniere's Disease (image):
