The Journal of Neurotrauma - 6

EXPERT PANEL DISCUSSION
Dr. Puccio: I have to agree with Dr. Manley in that I
do think that the most promising tool is an objective
blood biomarker at point of care. It would be great to
be able to use a finger prick instead of having a venipuncture, similar to the diabetic population, as opposed to having a venipuncture and a small delay in
processing. Many are working to improve this method.
I also wanted to comment on something that you had
talked about with TRACK-TBI recruiting a more severe population and missing the milder, concussion
patients. As you know, with seatbelts and airbags and
many recent technologies that we have had through the
years, even though patients are presenting to a level 1
center, there are a lot of lesser impact injuries presenting there. You do have many of the sub-concussive
patients that we did capture in TRACK-TBI, as
Dr. Bazarian said, with some of the negative CT scans.
And we all have seen in football games, for example, tackles and plays having a harder impact than
some of the car accident victims that we have seen
come through the emergency department, even at a
level 1 center, with a little fender-bender. I do think
that we have seen and tracked a combination of the
whole spectrum of TBI injury in some fashion within
TRACK-TBI.
I also wanted to comment on Dr. Bazarian's comment that the timing of the concussion is a factor. We
did another study in Pittsburgh looking at chronic TBI,
TEAM TBI (Targeted, Evaluation, and Management
study).7 Participants who have dealt with their concussions through the years, even though they may have
been seen in a concussion clinic and had some treatments, tend to maladapt, and they are still having to
deal with symptomatology through the years. So not
only is the timing of concussion assessment important,
but so is obtaining the correct treatment for their
concussion symptoms.
But to get back to the original question, I do think
that an objective biomarker in the initial assessment of
the concussion is what we should be targeting.
Dr. Marion: Dr. Puccio, there are several other
technologies out there such as eye tracking, qEEG,
and balance testing. Among all of those techniques,
do you still think blood biomarkers are most
promising?
Dr. Puccio: Yes, because obtaining a lab test for diagnosis is the practice within a hospital setting that
clinicians are used to - a quick triage. However, I do
think that balance testing and other assessments may
be more relative to a sports concussion-type setting or
a later presentation setting in a clinic, because more
time can be devoted. But in the emergency department, I do think that a blood biomarker is most
promising to advance.
6

Dr. Marion: Thank you. Dr. Bazarian, do you agree
with that, or would you rather have an eye tracking
device?
Dr. Bazarian: Eye tracking is very interesting. It is
relatively new, and I think we are just starting to understand how concussion may affect ocular motor
function, and there may be different eye tracking signatures for different diseases. But, I don't think eye
tracking is nearly there yet. There is not nearly as robust an evidence base as there is for EEG.
Frankly, I like EEG as a potential objective marker.
It can potentially work along with biomarkers. The
EEGs have been around for a long, long time, almost
100 years now, and I think there is some evidence that
if you can quantify some of these EEG features, there
are ways to classify subjects acutely and maybe even
see them improve over time.
I would love to see how the markers compare with
the EEG, head to head, and I would also love to see
how they might complement each other. They are both
different views of the heart, and we may need more
than one kind of view of the brain.
Dr. Marion: Dr. Gill, what are the most promising
blood-based biomarkers?
Dr. Gill: So I think some of promising biomarkers that
we have seen just in total blood, specifically GFAP as
well as UCHL1, especially in that acute period within
24 hours, is very indicative of having a concussion,
and that is what we have seen in CARE as well as some
of the mild TBI studies that we have had.
When we transition in the subacute recovery period
following a brain injury, tau and NfL play a bigger
role in that. We have some promising findings from
our lab that show that tau at 24 hours is particularly
predictive of having a longer return to play, and that
is something that is from the CARE Consortium, and
a replication of one of the studies that I did with Jeff
Bazarian.
Currently, my lab is looking at not just total tau and
it's link to recovery, but we are also focusing on
phosphorylated tau, as this may provide more promise
in understanding biomarkers that are prognostic of
recovery. We have been waiting for the technology to
catch up with us, and luckily, we have had that happen.
So now we are going to be able hopefully to get more
accuracy. We are not just looking at total tau, but the
components of tau, which we know would be much
more problematic, especially if tau becomes hyperphosphorylized, and we could detect that in the blood.
That will be a component of our upcoming studies.
There is definitely diagnostic value in GFAP and
UCHL1, and then with NfL and tau we see more in the
chronic phase being more indicative.
ª 2020 by MARY ANN LIEBERT, INC.

The Journal of Neurotrauma

Table of Contents for the Digital Edition of The Journal of Neurotrauma