Interactive Transcript
1:56
But I hope to provide a more broad-based illustrative
2:01
review of the various types of pathology that
2:04
we encounter in daily practice.
2:06
So, in a top-down fashion from the face to
2:10
the skull base, to the thoracic inlet.
2:13
I'm going to start with
2:16
discussion of acute traumatic injuries and then shift to
2:19
infections. And at the end, I'm going to conclude on some
2:22
emergency cases that can be seen among the specific
2:26
population of treated head and neck cancer patients.
2:32
So, in the head and neck region,
2:34
there's a very limited role of the plain
2:37
radiograph in the emergency setting.
2:39
Though, they can be helpful in the setting of the pediatric
2:43
airway evaluation, or occasionally, for ingested
2:46
foreign bodies.
2:47
Similarly, in the ED setting,
2:50
ultrasound has a very limited role.
2:53
Because time is of the essence,
2:55
our workhorse is essentially CT with MRI reserved
2:59
for problem solving.
3:01
CT is fast, especially in the era of multi detector CT
3:05
and exams can be completed from start to finish
3:08
in the order of minutes.
3:10
They are far less prone to motion artifacts.
3:13
CT provides excellent and atomic detail with high
3:16
spatial resolution.
3:18
It allows for multiplanar, 3D, rotational
3:22
reconstructions that can really enhance our understanding
3:25
of the pathology and question.
3:28
There are always issues of radiation exposure,
3:31
but when the clinical concern is high enough,
3:34
the risk-benefit ratio often favors imaging over
3:37
withholding imaging in the urgent setting.
3:42
Contrast exposure is also less of a concern in the
3:45
ED setting and usually if contrast is needed,
3:49
we give it to make the diagnosis.
3:53
If there is an issue of a severe contrast allergies,
3:56
many institutions have
4:00
steroid, diphenhydramine prep
4:04
established, which can be completed 4 to 24 hours,
4:07
prior to imaging.
4:10
On the other hand, MRI has high soft tissue resolution.
4:14
It is better at detecting disease with respect
4:17
to tiny structures such as the meninges
4:20
and the cranial nerves.
4:21
And very often, it can provide a lot of powerful insight on
4:26
bone, soft tissue, and vascular injuries.
4:30
On the upside, there is no radiation risk
4:32
but there is the issue of time.
4:35
Not only is it time-consuming to obtain the MR images,
4:38
but there also is a time sink and assessing the
4:43
potential contraindications to scanning.
4:46
Oftentimes, in the ED setting, patients may be obtunded.
4:50
They may not be consentable,
4:52
and it will be,
4:53
it can be difficult to find relatives to clear
4:56
the patient for prostheses and devices
5:01
in order to expedite the process.
5:11
There's also the issue of metallic ballistic injury,
5:14
which may be contraindicated in the trauma setting.
5:18
A contrast in the setting of renal disease with
5:22
the concern for inciting nephrogenic
5:24
systemic fibrosis has been debated
5:27
much in the last several years.
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The very recently, in the last week or so,
5:31
a recent consensus statement has been put out
5:34
by the ACR and the National Kidney Foundation,
5:37
which indicates that it is better to give a group 2
5:40
and group 3 gadolinium-based contrast agents
5:42
than withhold in most clinical situations,
5:45
even with the GFR less than 30.
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So, with that said,
5:49
I consider CT to be our workhorse and MRI to be a good
5:54
problem solving technique in specific clinical scenarios,
5:57
and we'll see some examples of that moving forward.
6:01
So our role in
6:04
diagnosis is, of course,
6:05
to make the relevant findings and report
6:07
expeditiously and accurately.
6:09
But it shouldn't just be limited to that.
6:12
In the ED setting, disease processes can proceed from
6:15
bad to worse very quickly.
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And it's really incumbent on us,
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not just to make the findings,
6:20
but to anticipate the complications.
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For example, an orbital abscess should prompt us
6:24
to look for venous thrombosis, ballistic injury in the neck
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should prompt a query for vascular integrity and
6:31
appropriate imaging recommendations for that.
6:35
Once we consider those potential complications,
6:37
we need to discuss those recommendations with
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the clinical service caring for the patient.
6:42
For example,
6:42
we would recommend a CT venogram exam to evaluate
6:46
for venous thrombosis in the orbital abscess setting,
6:49
or CTA neck to evaluate for vascular injury in the neck
6:52
following ballistic injury or recommend
6:55
ENT consultation for an otic capsule violating
6:58
temporal bone fracture.
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