(Transcribed by TurboScribe - Upgrade to Unlimited to remove this message.) Slide please, Gaetano.
All right, and now we are back to
our main speakers for today.
Again, as I mentioned at the beginning, our
incredible fellow team, they all have a number
of projects ongoing and have been presenting all
around the country and the world.
So we get to hear some of their
recent work that was presented at the CNS.
And Gaetano, I think you're going to be
going first, is that correct?
Yes, sir.
All right, let me share my screen.
All right, good morning everyone.
So today I'll be presenting on our initial
results of precision treatment of postoperative CSF leaks
with ultrasound-guided epidural blood patch.
And this is a talk that I gave
us in our presentation at CNS in Austin
and really was the work of the entire
spine team here at Mayo Clinic Florida, as
well as Dr. Clendan and James West.
I don't have any disclosures relevant to this
talk.
And as you know, incidental durotomy is a
very well-known complication of spine surgery.
And if left untreated, it can lead to
a persistent CSF leak or a pseudomeningocele.
The reported rate of incidental durotomy ranges from
4% to 16%, depending on the index
operation.
And if patients develop symptoms of persistent CSF
leak, first-line treatment is bedrest.
Other options include over-sewing the wound and
placement of a lumbar drain.
And there is the potential need of having
to go back to the OR for direct
repair.
While epidural blood patches are routinely used to
treat post-anesthesia or post-LP CSF leaks,
they are not often used after spine surgery
for durotomy repair.
The problem is that the ultrasound is a
great technique that allows radiation-free and direct
real-time visualization of the pseudomeningocele, the dura,
and the toy needle.
But this application in the native spine is
often very limited.
That's magnified in the post-operative spine, thanks
to the bone work that has been done
by removing the bony anatomy and the ligaments
there, which allows a window for the ultrasound
and for the needle to be visualized properly.
So in our study, we did a retrospective
analysis of patients underwent the USCBP at Mayo
Clinic, Florida, from 2009 to 2020 for symptomatic
pseudomeningocele secondary to spine surgery.
We collected demographic, procedural, and outcome characteristics.
The primary outcome of our study was ultrasound
EBP success, defined as a resolution of the
initial symptom that brought the pseudomeningocele to clinical
attention, such as postural headaches, incisional leak.
So for our technique, patients are position-prone.
The ultrasound is used to localize the pseudomeningocele,
and the color doppler can also be adopted
to determine if there are any active sites
of CSF leak of ingression.
Under ultrasound guidance, an 18-gauge toy needle
is advanced into the pseudomeningocele, and the content
is aspirated.
The needle is then advanced into the epidural
space, and about 30 ml of autologous blood
is injected epidurally in 5-10 ml aliquots
under continuous ultrasound guidance.
Then after waiting for 5-10 minutes to
allow the blood patch to sit, the ultrasound
is then used again to confirm the placement
of the patch, and the color doppler can
also be used to confirm an absence of
CSF regress if that was previously identified.
So overall, we had 48 patients who underwent
a total of 61 USCBPs, and you can
see that the most frequent index operation was
a laminectomy, 24.5%, and about 36.7
% of these cases were revision surgeries, and
also that the incident of derotomy was unrecognized
during the surgery in about 22% of
cases.
You can see here that the median time
from surgery to symptom development was 7 days,
and the most frequent symptoms of representation were
postural headaches in 64% of cases and
incisional leak in 26.5% of cases.
Here, looking at the results of the EBP
under ultrasound guidance, you can see that 51
% of patients experienced resolution of their symptom
after their first blood patch, and you can
see that the median volume aspirated from the
pseudomeningocele was 34 ml, and also that another
20% of patients experienced resolution of their
symptom after subsequent attempts of blood patches.
We're talking about complication.
We had about 14% complication in our
series, and the most frequent one was wound
infection in two patients, followed by meningitis also
in two patients.
Here is a couple of illustrative cases.
You can see here a patient that presented
with the dura laevi fistula, and here on
the t2-sagittal MRI, you can see a
fairly large pseudomeningocele after the patient had undergone
the laminectomies and obliteration of the EBP fistula,
and then the patient underwent an ultrasound, a
bit of a blood patch.
The contents of the pseudomeningocele was aspirated and
a blood patch placed, and then you can
see on the postoperative MRI, sagittal and axial
cut that was done one month after the
procedure, complete resolution of the pseudomeningocele.
This is another case of a patient that
laminectomy, as you can see here on the
CT scan, on the level above a previous
fusion construct, and there is an hypodensity there
of a fluid collection that was also again
identified under the ultrasound where you can see
the star there, and then the color Doppler
was used to identify the active CSF regression
there.
The 2A needle, you can see here in
white where this big arrow is, is inserted.
The contents of the pseudomeningocele is aspirated, as
you can see in figure E, and then
the blood patch is placed, and this is
a postoperative scan that documents resolution of the
pseudomeningocele.
So, our study carries all the limitations of
all single institutional retrospective studies.
Therefore, further prospective and multi-centered studies are
needed to confirm the generalizability of our data,
but our study is the first in the
largest series describing the adoption of US EBP
in patients presenting with persistent pseudomeningocele and CSF
leak following spine surgery.
We found an overall success rate of over
70% with a first attempt success rate
of 50%.
So, this suggests that the utilization of US
-guided EBP in expert hand may allow for
targeted treatment of a large portion of symptomatic
postoperative pseudomeningoceles.
Thank you.
Gattano, that's excellent work.
Congratulations.
That's a novel treatment for these non-uncommon
problems.
One thing that, you know, I realized I
never asked Dr. Miller or Dr. Clendenin, what's
the consistency of the blood that you're using
as the patch, and how long is it
in between obtaining the autologous blood and actually
injecting it?
I don't know about the time between the
when the blood is drawn and injected, sir,
but most of them, I believe it may
have been done at the same time of
the procedure, sir.
Yeah, but I mean, they aspirate it and
then immediately give it, you know, I was
just curious about how thick the blood is.
Maybe, Elliard, I see Dr. Brahasi.
Yeah, I do some of these as well.
Okay.
And yeah, we go right away for the
blood, you know, so it's right from an
IV catheter to the epidural space.
But you know, what's really helpful is the
Tissiel fibrin glue.
So it's like in our, you know, human
fibrin blood components that we inject, and that
solidifies much, much quicker, and it's much more
firm.
So, you know, with the blood, it's thinner
and can get into different crevices, while the
fibrin glue is a bit more firm.
So you try to get both properties in
there right at the leak.
Excellent.
Yeah, thanks.
Thanks, Tien.
I appreciate that.
Elliard, did you want to give us your
hand up there?
Do you want to make a comment?
Yeah, yeah.
Sorry, I can't join on camera because I'm
tied up in the hospital.
But I would like to second those comments.
I've done this couple of cases with Dr.
Quinden, and a lot of times what we
do is we place an arterial line, so
that way we can reliably draw blood right
away as soon as access is identified with
the ultrasound machine.
And yeah, fibrin glue has also been something
new that's been very helpful for this case.
One question that I had, and it's something
that we always worry about, is the risk
of infection and meningitis.
And it's interesting from the data presented, there
was about two, I believe.
Any thoughts on, you know, looking at the
data, anything that we can do to make
things better or reduce that risk?
Or is this contributed directly to the block
itself?
Or was there other circumstances on those two
patients that got infections?
Thank you.
Yes, sir.
Excellent question.
As you said, yeah, we had about two
patients, about 4% for our series.
It's a small series, so it's difficult to
generalize if that's really a 4% for
the procedure itself.
But that was assumed to be related, was
meningitis assumed to be related to the procedure,
not like a UTI or any other infections.
And let's see, we have a question from
Dr. Vargas about what about the presence of
fibrous tissue after the procedure?
And I think...
Yeah, so these are usually done like, scar,
that sort of thing.
Yeah, so these are usually done right after
the procedure.
It's not too long.
And that's why it's very difficult to do
them anatomically guided.
That's why the ultrasound really helps to visualize
the anatomy.
And as far as we didn't have any
issues as far as going through fibrous tissue
or the patches.
Great.
Well, thank you so much, Gaetano.
Yeah, a couple more points here.
Dr. Dean mentioned would emphasize the need to
make sure patient is a febrile and has
normal white blood cell count prior to the
blood patch.
And I know that's part of the protocol
and a good point.
Some of these patients are immediate post-operative.
They have an immediate post-operative status, so
they might have an elevated white blood cell
count just from surgery.
But yeah, very, very good point.
So, all right.
So excellent work, Gaetano.
And we will go on to the next
presentation.
We have Dr. Garcia, who's going to be
presenting next.
Can you see this, Dr. Fox?
Yes.
Oh, it's advancing by itself.
All right.
So morning, everyone.
Today, I'm going to be presenting on SPECT
-CT as a predictor of pain generators in
patients undergoing inter-articulate injections for neck and
back pain.
I think most of you already know of
this project.
It's a project that we did with the
spine group and on the particular mentorship of
Dr. Oboriyama.
And we presented it at Austin at the
Congress of Neurological Surgeons.
So, as you know, low back pain and
also neck pain, but there's a lot more
literature on low back pain, is one of
the main leading causes of disability in general.
And yet, the identification of painful generators is
still difficult, despite the use of multiple morphological
-based studies, including x-ray, CT, MRI, and
also compounded by the fact that sometimes structural
abnormalities that are found on the scans have
no direct correlation with the actual pain of
the patient, which makes the correct identification of
the painful generator difficult.
And therefore, the targeted treatment for that painful
generator also difficult and limited.
With this in mind, there have been some
interest in functional-based tests, like SPECT, to
accurately identify those painful generators.
More recently, a scan has been developed, which
is called the hybrid SPECT-CT, which at
Mayo we have been fortunate to have available
for a number of years and with good
quality, as I'm going to show in one
of the example scans.
So, the idea here was to look at
facet joint injections, targeted injections, and see whether
or not the hypothesis that injections targeted at
positive sites of uptake would do better than
injections targeted at foci without uptake.
So, to accomplish this, we designed a study
with a single institution retrospective, in which we
compared both short and long-term outcomes for
patients undergoing facet joint injections for neck and
back pain.
Given the large sample size, I was able
to do a propensity score match to adjust
for age, gender, BMI, hypertension, and multiple target
injections and injection location.
We did exclude sacroiliac joint injections, given that
they are a bit different and they should
not be grouped all the same with cervical,
thoracic, and lumbar injections.
So, these were our main outcomes.
We looked at immediate positive response, change in
VAS two weeks after injection, improvement in VAS
above 50 and 70 percent after injection, and
need for additional treatment, both injection and surgery.
Importantly, at Mayo, we have people who do
call these patients two weeks after the procedure
who are not implicated in the research.
So, they're able to give us an unbiased
feedback from the patient regarding patient report outcomes,
which allowed us to really objectify these outcomes.
So, as you can see, we have a
large number of patients, 2,849 patients that
were evaluated with SPECT-CT within five years.
Out of these ones, we had 340 with
facet injections within 150 days after SPECT-CT.
Why 150 days?
We had to choose a threshold.
There is no specific literature on the threshold.
We just had to come up with a
threshold that would allow us to look at
outcomes that were associated with injection, not associated
with something else that could have happened in
the interlude.
So, we had a total of 140 cervical
injections, 21 thoracic injections, and 207 lumbar injections.
Importantly, 265 were uptake-targeted injections.
By this, we mean that all the injections
were targeted at facet of uptake, all of
them.
That was our definition of uptake-targeted injections,
and 75 were non-uptake-targeted injections.
So, as you can see here, just an
example of a SPECT-CT at Mayo with,
in this particular patient, a right L4-L5
facet joint having uptake that was targeted by
injections.
This is actually one of the cases that
was included in the study.
So, here are just some demographics and characteristics
of the location and characteristics of the injection.
As you can see, even though there is
nothing that is statistically significant, it can always
compound and have a confounding effect on the
variables, hence why we did the propensity score
match to adjust for all these variables.
What you can see here is that both
on a univariable analysis and a multivariable analysis,
we did not find statistically significant differences between
non-uptake and uptake- targeted injections, but
when we did look at patients who already
had a failed injection before the SPECT-CT
and in which the surgeon or procedurist was
able to change the target based on the
information of the SPECT-CT, here below, what
you can see is that in those patients,
we do have a benefit, and the benefit
was particularly greater if there was any change
made on the target.
So, that is very suggestive that for a
particular set of patients with adequate patient selection,
you do see a benefit with SPECT-CT
to guide facet-trained injections.
So, basically, our conclusions seem to support that
pending adequate patient selection, SPECT-CT has a
benefit in guiding facet injections.
There are limitations, of course, with our retrospective
single institution study, but we did use a
propensity score to match for confounding variables.
We have a large sample size, but of
course, future directions would have to be prospective,
multi-side, hopefully, double-blind clinical trial to
accurately discern the impact of SPECT-CT in
routine clinical practice.
And I'll take any questions.
Excellent, Diogo.
Really fabulous work, and I think this is,
you know, there's so much potential applicability to
using imaging biomarkers for better delineating patients' pain.
You know, in this, you know, even with
the precision of these SPECT studies, it shows
how challenging it can be to figure out
pain generators in the spine, and I think
this is incredible work with a lot of
promise.
Based on what you've seen so far, who
do you think, I mean, we should be
doing this more or less, or do you
think people should have this up front?
I mean, how do you recommend we use
this based on your knowledge of the technique
in our everyday practice?
So, the patients that I did see have
a benefit were patients in which there had
already been an attempt at an injection.
So, because my understanding is that SPECT-CT
is sensitive, but not necessarily specific, so it's
difficult to figure out which of those facets
that are lighting up are the ones that
are actually causing pain.
So, when we have the benefit of having
a patient that already had a procedure that
failed, we do know which of those joints
did light it up, but they're not the
actual painful generator, so we can take those
out and pursue the next ones.
So, I do see SPECT-CT not as
a necessary first line for any patient that
has a first procedure, but for a recurrent
facet injection, for a patient who has not
benefited from a facet injection, I would definitely
see benefit there.
But, of course, I think to actually make
a recommendation, we would have to have a
double-blind clinical trial so we can make
a recommendation.
Hopefully coming.
Hopefully so.
Yeah, and we'll continue to learn more about
these imaging biomarkers, which I think will be
very helpful.
Dr. Dean makes a great point in the
comments as well that we have extremely high
-quality SPECT studies at Mayo, which, you know,
I completely agree.
At UF, we didn't do this at all,
so this was something novel to me seeing
here, and I'm very impressed with the quality
of these studies.
So, excellent work.
All right, I think we can move on
now to our next presentation.
Dr. Vivas Butrago, who is going to be
speaking about supermarginal resection impact on overall survival
for IDH wild-type glioblastoma.
Perfect, sir.
Can you hear me now?
Yes.
Yes, thank you.
Let me share the screen here.
All right.
Are you seeing my slide?
Yes.
Perfect.
Good morning, everyone.
Thank you for attending this lecture today.
So, I'm going to present our study that
we presented in October this year in CNS.
The title of this study is supermarginal resection
impact on overall survival for IDH wild-type
glioblastoma according to their cell density distribution and
infiltration profile.
This is a mathematical model.
So, we have no disclosures for this lecture.
So, a bit of background regarding the extent
of resection on glioblastoma.
We know that not long ago, the most
common surgical recommendation for glioblastoma was to perform
only a biopsy, and this was not only
in the United States but worldwide.
But since the 2000s, we started seeing very
important studies from Dr. LaCroix, from Dr. McGirt,
from Dr. Sanai, from UCSF with Dr. Berger,
and from Dr. Chaychana and Dr. Quinones with
this data from Hopkins that all of these
studies were in favor of performing more extensive
surgical resection on patients with glioblastoma, and the
results were pretty much homogeneous, identifying that resections
above 78% of the contrast enhancement in
T1 were associated with a significant improvement in
overall survival in patients with GBM.
But furthermore, we see that the gross total
resection is this complete surgical resection of the
contrast enhancement component of the tumor that you
can see up here.
But what about the flare component in the
T2 sequence?
We have known for a while already that
there are infiltrated GBM cells within the brain
tissue that most of the time is not
being taken care of or resected because of
the infiltrated behavior of these cells within functional
brain tissue that if you resected it, you
can cause a deficit in the functionality of
the patient.
So we end with our group at Mayo
Clinic to start looking at the extent of
the supermarginal resection beyond the margins of the
contrast enhancement tumor.
And we have seen that regarding this topic
that it has been influenced by the results
from the good results from extended resection beyond
the margins in lower gliomas.
We see here the very important papers from
MD Anderson, from Hopkins, from Cleveland Clinic, and
from UCSF.
And not all of them have homogeneous results
as we found before in the gross total
resection for the T1 contrast.
So we wanted to give it a shot.
And thanks to all the data that we
have at Mayo Clinic with the high flow
of patients, we were able to do this
study in which we identified more than 800
patients.
And we selected only those patients that were
IDH mutants.
This is the most aggressive type of GBM
that has a less overall survival in total.
So we only selected those patients that had
a gross total resection of the contrast enhancement,
and that they did present before the surgery
with some degree of preoperative flare.
So in total, we included 101 patients.
We performed all volumetric analysis on all the
sequences in the contrast enhancement, in the necrosis
part, and in the flare for all the
patients.
And we did find in the univariate and
multivariate analysis that increasing SMR as it continues
viral for the first time, we can show
that is statistically significant for an increase and
improved overall survival in our patient population.
And furthermore, when we perform a threshold analysis,
we found that those resections above 20%
and less than 60% were the ones
that were related with a significant increase in
overall survival.
So to summarize our findings, we did this
illustration that just shows that, you know, in
the green part, in the green portion, are
the percentages from above 20% and less
than 60% that were related with an
improved overall survival.
And we didn't find significant benefit in those
resections above 60%.
That is the red portion of the figure
here.
So now we know that increasing SMR is
beneficial for an improved overall survival in our
patients with IDH-type, wild-type GBM.
But we know that there is also a
high variability in the radiological presentation of our
group in general in GBM, but also in
IDH wild-type.
So we partnered with the Mathematical Neuro-Oncology
Laboratory at Mayo Clinic Arizona with Dr. Christine
Swanson to try to further personalize the, to
try to be more specific with using specific
patient characteristics from the radiological data.
And we can see that following our hypothesis
at the center of the lesion, the one
that is in close proximity with the contrast
enhancement part, has a greater tumor burden cell
concentration over there.
And once you are going to the periphery,
you see that the low density, that the
density of these tumor cells is lower.
So this is the formula that was used
in our patient population.
In summary, for the interest of time, you
can see that in the T1 with contrast,
the volume was approximated to an aspheric shape.
And we saw that this part, this portion
has a greater cell density compared to the
cell density in the T2 pair.
So with these results, we classified our patient
population in three groups that were nodular, moderately
diffused, and highly diffused according to their tumor
cell density and distribution profile.
So this is a representation from some of
the patients that were selected and classified and
included in these three groups.
You can see here in the nodular, they
have more contrast enhancement than flare.
And see in the moderately diffused, you see
that there is some more flare in the
patients surrounding the post-gastrointestinal T1.
And in the highly diffused, you see that
the flare is greater than in the other
groups.
So for this, in the univariate analysis, we
saw that it was statistically significant only for
moderate and diffused and highly diffused.
But it was not significant for nodular.
This is in univariate.
And the same results were obtained for the
multivariate analysis.
It was statistically significant for moderate and highly
diffused, not for nodular.
But when we performed a tracer analysis, we
saw that for the nodular, there is actually
a benefit only in resections from 10%
to 10%.
And this is kind of logical because, you
know, in the nodular, there is not much
flare, as we showed you in the MRI
before.
So there is not much benefit in extended
resection beyond the 20% of the contrast
enhancement in the nodular group.
In the moderately diffused, we found benefits from
all the way up to 50%, you can
see here.
In the highly diffused, we only saw benefits
beyond 30% all the way up to
90% and 90-plus percent.
So this is very important because now we
can, based on this study, at least in
these results, we see that there is a
very important benefit in the supramarginal resection of
these patients.
And of course, based on their radiological characteristics
before the surgery, the surgeons can decide how
much the patients can need a resection, an
extended resection based on this.
And for example, in these highly diffused tumors,
we found that this is the maximum SMR
correlated with beneficial viral survival.
You can see that patients that had a
resection above 90% had a better overall
survival than the ones that had less than
90%.
And this patient population had a greater survival
of, let's see, if I remember correctly, almost
nine months greater than the patient that had
a resection with less than 90%.
For the moderately diffused, the highest SMR percentage
was 50.
And this patient presented with a benefit of
an additional seven months.
And in the nodular patients, the highest maximum
significant SMR correlated with beneficial viral survival was
20%.