Movement
Disorders: Generalized Dystonia
Transcript:
Guest: Dr. Vanessa Hinson -
Neurology
Host: Dr. Linda Austin –
Psychiatry
Dr. Linda Austin: I’m Dr.
Linda Austin. I’m interviewing Dr.
Vanessa Hinson who is Assistant Professor of Neurology and Director of the
Movement Disorders Program here at the Medical University of South Carolina. Dr. Hinson, you’re an expert in the treatment
of a movement disorder called a dystonia.
Just what is a dystonia?
Dr. Vanessa Hinson: A
dystonia is an abnormal muscle contraction.
And, interestingly, the origin of the dystonia is not the muscle itself,
but the brain. The brain basically gives
patients with dystonia an abnormal signal to then respond with an abnormal and
often painful muscle contraction. The
dystonia can manifest itself in the whole body in the form of a generalized
dystonia or it can be focal, isolated to one specific body part.
Patients with focal dystonias have muscle contractions in one
isolated body part, for example, their neck, where they have a twisted neck
posture that can be painful. These
patients are unable to turn the head fully left or right, front or back, so
they’re very restricted in their movement and have painful muscle spasms. The focal dystonias can also affect the hand,
in the form of writer’s cramp, for example, where a patient tries to write and
suddenly the hand assumes a painful contracture and the patient is unable to
complete their writing task. So, those
would be focal dystonias, whereas a
generalized dystonia, a patient would have spasms in the back muscles, the neck
muscles as well as the eye and leg muscles, might not be able to walk or sit if
not treated.
Dr. Linda Austin: So, would
something as simple and common as a charley horse that wakes you up in the
middle of the night, a leg spasm, be considered a dystonia?
Dr. Vanessa Hinson: That is
not considered a dystonia. A dystonia,
per definition, is a sustained abnormal muscle contraction. So, a patient, before we diagnose with
dystonia, would come with a typical history of, my neck is turning to the left constantly and there’s nothing I can do to
correct that. Or, if it affects the
eye muscles, they would say, my eyes are
constantly pulled shut because my eye muscles are pulling all the time,
and, how can we help that? It wouldn’t
be an isolated incident.
Dr. Linda Austin: I
see. So, waking up with a stiff neck
that resolves in the course of a day, that is not a dystonia?
Dr. Vanessa Hinson: That is
not a dystonia, whereas, if the stiff neck persists, over months, that could
possibly be a dystonia and we would have to look at that more closely.
Dr. Linda Austin: Let’s
talk first about the generalized dystonia.
What causes that?
Dr. Vanessa Hinson: Often
times generalized dystonia is genetic.
Actually, the DYT1 gene mutation is the most common cause of generalized
dystonia. Often times children are
affected, young children, first, with an abnormal muscle spasm in one leg, and
then later their back might be affected and their arms and neck as well. These youngsters usually have a positive
family history where a relative is affected with the same disorder as it is
autosomal dominant, which means that 50 percent of the children of an affected
adult can have the dystonia as well. So,
this often times runs in families.
Dr. Linda Austin: How
severe can that become? Can it become
really disabling?
Dr. Vanessa Hinson:
Generalized dystonias are the most severe cases of dystonias and more
rare than the focal ones. Generalized
dystonia is very severe and often times affected subjects cannot sit in a chair
because their muscles pull so much that they cannot sit up right. Sometimes they come to my office and have to
lie on the stretcher or on a bed the whole time that we talk. They have difficulty walking. They have difficulty swallowing, chewing
food. This can be quite dramatic. And in those instances, often times we have
to resort to surgical treatment options to correct the disorder.
Dr. Linda Austin: How
successful are those surgical treatments?
Dr. Linda Austin: Surgical
treatment is indicated for patients who fail, of course, other treatment
approaches, with medication by mouth or injections with certain chemodenervation
therapeutics. The surgery for dystonia
is called deep brain stimulation (DBS).
And, with deep brain stimulation we can calm a lot of these excessive
muscle contractions down to an extent where the patient can be comfortable,
they can sit in a chair. They can walk
much more normally than before. And they
can regain a lot of their quality of life that the dystonia might have taken
from them. The surgery is relatively
new. It’s only been done for a few
years. And we’re one of the few centers
is this country to offer it.
Dr. Linda Austin: Who,
here, does that surgery?
Dr. Vanessa Hinson: Dr. Istvan Takacs, from the stereotactic neurosurgery program, is our surgeon. Usually, patients see me first to get my
input, whether the surgery would be helpful in their case, and then they’re
referred to Dr. Takacs for another look and planning of the surgical procedure.
Dr. Linda Austin: Do you
know what percent of cases have a reasonably successful outcome from that
surgery?
Dr. Vanessa Hinson: If one
has a genetic form of dystonia, if one takes the blood test for the DYT1 gene
that I was talking about earlier, there’s a very good chance, in the range of
80 percent, that one gets dramatically better.
If one has a generalized dystonia and does not have that particular
genetic abnormality, I would say that the chances are more in the 60 percent
range of substantial improvement. We do
see improvement to some degree in all patients who go to surgery. The question is, how dramatic will it
be? And, in the gene-positive patients,
we see very dramatic improvements, whereas, in the other category of patients,
there will still be improvement, but maybe not to an extent compared to the
gene-positive patient.
Dr. Linda Austin: But you
mentioned that before a patient gets to surgery, you try medications first, so
those must be reasonably effective as well?
Is that correct?
Dr. Vanessa Hinson:
Medications, I would say, in severe generalized dystonia, can be helpful
to alleviate pain and some of the excessive contractions. But, once a patient reaches a stage where
they can’t sit in a chair or they can’t walk, they probably need surgery, and
by-mouth medications are not going to be potent enough to relieve this problem.
Dr. Linda Austin: Dr.
Hinson, let’s talk about the focal dystonia in another podcast. Thanks so much.
Dr. Vanessa Hinson: Thank
you.
If you have any questions about the services
or programs offered at the Medical University of South
Carolina or if you would like to schedule an
appointment with one of our physicians, please call MUSC Health
Connection: (843) 792-1414.