Ultrasound for the Novice - HD

Introduction

I am Dr. Ted Lyons, a professor of radiology, obstetrics, gynecology, and anatomy.

Objectives of the Talk

The talk that I'm going to give today is basics, ultrasound, ultrasound for the novice.

The objectives of this talk are to help the individual who knows virtually nothing about ultrasound, identify some of the basic issues in ultrasound, but most importantly to focus on how using ultrasound you can help your patients.

So what I'm gonna do is describe some of the basics of ultrasound equipment, including how to hold the probe and basic controls to optimize the images, to distinguish solid from fluid, which is a key for ultrasound and to recognize liver, spleen, kidney aorta, jugular vein, thyroid and carotid artery.

So it's just an overview of the basics of ultrasound.

The Role of the Ultrasound Physician or Sonographer

The role of the ultrasound physician or sonographer must be to answer the question that is your role.

What is the clinical question?

It's the patient's problem.

It's why the patient came to see the doctor.

So often we get a requisition from a clinician with their guess as to what the problem might be.

A patient comes in with right upper quadrant pain, their guess is gallstones, but that's not the patient's problem.

The patient's problem is right upper quadrant pain.

And your job is to identify the cause of the right upper quadrant pain.

You have to talk to the patient, the sonographer or the physician, ultrasound physician has to talk to the patient.

So often clinicians are too busy that they don't have enough time to talk to the patient.

You have a tool with ultrasound that can actually allow you to examine the patient.

So talk to the patient, listen to what they're saying, and then using ultrasound, examine the patient.

And your ultimate goal is to answer the question.

If you can answer the question as to what the patient's problem is, you will be doing that individual.

A tremendous service.

Training and Challenges in Ultrasound

Ultrasound is not like brain surgery. It's harder.

A hospital will only allow you to do brain surgery after a five and six year residency.

But today, everyone is doing ultrasound with almost no training.

Some do six months, some do a weekend, some do two hours, but most do no training at all.

They learn how to turn on the power, grab a probe, and that's it.

And often they're being taught by people who have similar lack of training.

And is this the way you wanna learn ultrasound?

The blind alert, leading the blind.

You don't, you want to do it properly, realize that you don't know, and you need to go to sources to find out.

The hardest part in ultrasound is to create an image that you can interpret in most other technologies.

Ct, Mr x-ray, somebody else who is trained, creates the images.

And your job is then to just interpret well in ultrasound, the operator has to create the image, and the next difficult part is to know what it means.

And finally, how it fits into the clinical picture.

Remember, it's always easy to know what you're doing.

It's always easy if you know what you're doing.

Ben Franklin once said, failing to prepare is preparing to fail.

Ultrasound is a great tool once you know how to use it.

Basics of Ultrasound: Analogy to Painting

So let's begin. Ultrasound is like painting.

What you're trying to do with the ultrasound image and the various probes is to paint a picture.

You could use a giant painter's house brush that will give you broad brush strokes, but if you want the fine detail, you need a painter's palette with specific brushes to get the exact detail that you want.

You want to have wide brushes, very narrow and pointed brushes to get the real fine detail of the images that you're trying to create.

And you have that on the ultrasound machine.

You have an array of probes that have different lengths, different sizes, different frequencies, all designed to give you that array of brushes to create the ideal image from which then to make a diagnosis.

Variety of Transducers

So a variety of transducers.

We have an intraluminal probe that has frequencies between five and nine megahertz today.

It's a long probe that actually goes in the vagina and allows you to look at the uterus or into the rectum and allows you to look at the prostate and seminal vesicles.

The linear array probe is smaller, shorter, with a flat surface that is excellent for superficial structures such as the thyroid or testicles.

And again, it has a high frequency at nine megahertz and some go up to 12, 14, 18 megahertz.

And then you have the curved array probe that is lower frequency three to five megahertz and allows you to get into deeper structures.

So you would use this in the abdomen for the kidneys, liver, spleen, et cetera.

So to create a detailed image, use a fine brush, always use the highest frequency possible for your particular job, and use a smallish transducer to try and get the most detailed information.

With a course brush, a big, large transducer and a low frequency.

You are gonna get poor, relatively poor images, particularly if you're looking for that fine detail.

In patients who are very large with a lot of fat, because ultrasound does not go well through fat.

You may have to use a larger transducer and a lower frequency probe in order to get through that fat.

And of course, in that situation, you can expect that you're not going to get ideal images.

So a fat patient is difficult For ultrasound, the ideal patient for ultrasound is the nice thin patient that we have here.

History and Evolution of Ultrasound Imaging

This is an old scanner from 1975 where we used an articulated arm.

The probe was right here on the end of the arm, and we would sweep back and forth over the abdomen, going over the entire abdomen, creating the image on a Polaroid time lapse photograph.

But with this image, you can get large field of view scans that we can't get today with our ordinary sector scan.

In this image from 1978, it shows a distended abdomen of a patient who was on ovarian hyperstimulation and had developed very large ovarian cysts.

Also, one of the big dilemmas in the seventies was should images be white image on a black background or black image on a white background.

So here we have the white background time, but ultimately the black background one out here.

We have myself scanning again with a B scan, an old articulated arm scanner, in 1973.

This was published in our local newspaper.

This is my wife's uterus gestational sac and tiny little embryo of my daughter with embryonic cardiac activity.

And then later on at 16 weeks, you can see her fetal head.

It was all black and white.

At that time, we didn't have gray scale.

Today's imaging, you have gray scale and you have exquisite images such as you would see here.

Types of Ultrasound Images

So these are the various types of images you can create.

You can create just a static 2D image.

You can create a real time movie such as you see here looking at the blood flow and here looking at the fetal heart and the fetus breathing, or a single 2D image that just sits there.

And presents the anatomy as it is at that particular point in time.

So you can get gray scale, you can get color where you add color doppler over the two dimensional real time gray scale anatomy image.

The color gives you information about blood flow in that particular organ at that particular time.

Orienting in Real-Time Scanning

Let's deal with the real body.

In real time scanning.

It's hard to get all of the external landmarks.

You're using a probe in this case that is about three inches in length or nine centimeters.

It gives you a fan shape beam that goes into the body, and what you're looking at is a specific area in the body.

Here you're looking at liver, gallbladder, and kidney, but you don't have the other landmarks.

You don't have the vertebral bodies, you don't have the skin.

You're lacking landmarks.

If you're doing the examination, you know where you are.

If you're reading an examination after someone else has done it for you, you don't know where they were.

And that's always very difficult.

So the scan area is relatively small.

You have no external landmarks, so it's hard to get the big picture.

Here we have a patient has abdominal pain.

We're trying to figure out what the cause of the abdominal pain is.

Most of our patients are large patients, as you can see here.

And fat does not do well for ultrasound and air is totally reflected, totally reflects ultrasound.

So both fat and air.

In this particular patient, you have air, the bright echogenic structures and you have fat.

So both of these are gonna create a situation where this patient were not gonna be able to image very well.

It's a limitation of ultrasound in fat gassy patients.

Body Orientation

So the first thing is you have to orient yourself in the body.

You have to know what is anterior, what is posterior, what is superior and inferior.

The head is up here, the feet are down here, anterior and posterior.

And this is a sagittal view.

You can see it's a para sagittal view just to the right of the midline.

This is the orientation.

And you can see the liver, the gallbladder, the right kidney, the lungs are above the diaphragm, and the brown structures are muscle behind.

And all of this white is either intraperitoneal or omental fat or fat in the subcutaneous regions.

So this is what you're looking at.

How do you look at these images?

Well, you look at it from the side, you're taking a slice through the body, and you stand to the side and look at that image.

So you're looking at it with the patient's head to your left feet, to your right, anterior and posterior.

Interpreting Ultrasound Images

Here is an ultrasound image.

Without the anatomical references, the anterior skin surface would be here.

This structure is liver.

The tissue gives you small, fine little echoes.

There are black holes.

The black holes actually are fluid containing.

And in this situation, this would be the veins, the portal veins.

Here you see portal veins here, you often will see gallbladder sitting right there.

Remember that the patient's head is up here, feet are down there.

And this is a para sagittal scan.

One of the things we get is a very bright echo at the back of the liver.

That is in part the hemi diaphragm, but it's also the interface with lung.

Remember, lung is air containing and we don't do well with air.

Ultrasound does not pass through air.

Another image that gives you a little more information is a midline sagittal scan.

Remember the head is here, the feet are here, anterior and posterior.

And here you can see the liver has a little bit of a different shape.

Above the liver is the diaphragm, and above that is the echo free heart.

And in real time, you would be able to watch this thing move.

The aorta is a long tube that has major vessels coming off of it, the celiac axis and superior mesenteric artery.

And in front of it, you can see portal vein and the pancreas.

So it's very easy if I tell you exactly what these are.

It's also easy if you're doing the examination, you know where the transducer is.

You're familiar with what the anatomy looks like.

Ultrasound is a spectacular tool because it allows you to see non-invasively into the body and identify if there was a mass, what is the source of the mass?

If the patient is having pain, what is the tender organ?

This is critical for you to be able to answer the question.

Band Saw Scans for Reference

Now, if you have a band saw scan, this scan is an ideal scan.

Of course, this is a patient that I had injected with blue latex into the veins and we froze him.

Then did a section through the body, a sagittal view through the body.

So this is what you will actually see on ultrasound. Here.

You have the subcutaneous fat, the muscle or mental fat muscle, posteriorly and vertebral bodies here.

But things to recognize.

The blue injected inferior vena cava is really halfway through the body.

It's surprisingly far anterior.

Most people used to think, well, it's way at the back of the body, but in fact it's in the mid portion of the body and just anterior to it is the left lobe of the liver.

So anterior, posterior, superior, inferior.

Your orientation is very, very important.

A lot of people have trouble getting oriented when they're looking at these scans because this is not a usual way of viewing the image.

Normally we view them on fast as if you were meeting someone on the street.

You don't meet people that walk around in slices.

So the anterior abdominal wall is up there.

The inferior cava is in the middle, and the liver is between the two.

Here we can see also the hepatic veins, hv the hepatic veins.

So here would be an ultrasound equivalent image, the anterior abdominal wall, the liver with the left main portal vein.

You can see the left main portal vein here, and the vena cava here, and inferior vena cava.

Now if on all of your images, you could have the nice anatomical slices, it would make and labeled, of course it would make interpretation very easy.

But this is something that with time and with good instruction, you will be able to learn what these things are on the ultrasound image and what's normal and abnormal.

Clinical Application: Right Upper Quadrant Pain in Ideal Patient

So here's a patient that is the ideal thin patient.

This is the ideal person for ultrasound.

And she comes in with right upper quadrant pain.

So what you're gonna do first is you're gonna feel the patient or the clinician will palpate the right upper quadrant to see if there's any large masses to see if he or she can identify any source of pain.

Well, it's a lot easier. This is really using braille.

You're trying to feel what might be there.

If you put an ultrasound probe on the anterior abdominal wall and then move it across, you can actually visualize that whole right upper quadrant and get a better sense of what's going on.

And as you're moving it across, what you're seeing is the liver moving underneath you there you can see the kidney and the gallbladder.

So you're getting a complete sweep of the right upper quadrant.

We can see the diaphragm back there.

You can see the full extent of the liver.

And you can see are there any masses in there?

Is this the tender organ?

Is the gallbladder normal or abnormal?

This is a wonderful view in the ideal patient.

So this is what you should be using your ultrasound for.

Challenges in Obese Patients

Unfortunately, most patients who walk into the department are like this.

They're enormous. Fat is, fat may be beautiful, but fat is certainly a reality of our society.

And fat is not the friend of ultrasound.

And so a patient like this, not only would they be very difficult to palpate, there's the costal margin.

I mean, try palpating the liver or the kidneys or the gallbladder through this mass of fat.

It's gonna be almost impossible.

Ultrasound similarly is going to be difficult in this type of patient.

Here we have a patient also that has a big belly. He is fat.

We're using a sector probe with a low frequency.

And you can feel in this region to see if the abdominal pain is localized to the gallbladder.

But it's a lot better if you could actually see the gallbladder.

And with ultrasound, we can actually see the gallbladder.

Here is the same ultrasound image in this patient.

Gallbladders normal in size, the walls are somewhat thickened, and there is a curve.

Linear density echogenicity, curvilinear echogenicity with a distal shadow.

That means that all of the sound has been absorbed by this curve.

Linear density, usually that is calcification.

And calcium in the gallbladder means this patient has a gallstone.

But what you really need to do is you need to push on this area and say the words, does this hurt?

Is this the cause of your pain?

Gallstones can appear in all kinds of people, more common in the elderly, but they may not be the cause of the patient's pain.

So here you have a beautiful gallstone.

You still have to answer the question, is that the cause of the patient's pain?

Ultrasound Machine Controls and Optimization

Now, I'm just gonna show you a particular machine.

There's many different types of machines.

They all have a similar kind of configuration.

You'll have a control panel and you will have a screen.

You will have an on off button, and you will have usually a cart with various probes, a larger screen, a keyboard, and all the various knobs that allow you to get the best possible image.

Several buttons that are of importance.

The power button that as you turn it clockwise, it increases the amount of power in the transducer and gives you more information.

Of course, you're gonna want, you're gonna wanna make sure that the depth of the image is appropriate for what you're trying to visualize.

If you're trying to visualize the thyroid, it's a very superficial organ.

And so you may want to use only three or four centimeter depth.

Whereas in a large patient looking at the liver, you're gonna want to use 10 to 15 centimeters.

So changing the depth to give you an ideal area to focus on the area of interest.

Here you have a particular probe, 128 active crystals.

The probe or the ultrasound transducer, the active portion is 128 piezo electric crystals.

Piezo electric means mechanical to electric piezo.

Electric crystals converts mechanical to electrical signals.

So what happens is an electrical impulse hits the transfuser, often hits groups of crystals and activates them in groups to focus the ultrasound beam.

It sends out an ultrasound wave into the body for about 1% of every second.

And then for 99% of every second, it waits for the returning signal.

It waits for the returning echoes to come back, hit the crystals, send off an electrical impulse onto the screen and give you an image.

Types of Probes

There's a variety of transducers.

The intracavitary probe is a long probe, long handle probes you can get right into the vagina and the active transducer.

The crystals are in a tightly curled ring around the end of the probe.

For looking at superficial structures, you have a linear probe with 128 crystals.

And for looking at deeper structures, lower frequency curved array probe in every machine, there is some form of docking station or some form of place to attach all the different probes so that you have a variety that you can use at any one time to improve image quality.

Key Functions: Time Gain Compensation (TGC)

There are a number of functions that you have on all machines.

One is the time gain compensation.

In other words, because ultrasound is being absorbed as it goes through the body, if you could amplify the echoes from deep in the body and suppress some of the echoes superficially, you could then get a more even image throughout the body.

And that's what this TGC or time gain compensation does.

It suppresses some of the images, some of the sound superficially and amplifies the sound deep in the body and gives you a more uniform image on the screen.

So it adjusts the images so that the deep structures are adequately seen.

Remember that if you put in higher frequency ultrasound, you will get better image quality.

You can also manipulate the image quality and the images to get harmonics, which give you an even better image quality.

So harmonics and frequency and TGC all improve image quality.

You can see on the screen, you will get a diagram of what the TGC curve looks like when you've taken an image.

When you've identified an image that you want to store, it is very, very important.

And you can store it in the machine or send it off to a paper printer or to videotape or onto a picture archiving and communication device.

So here you can see a button to store a single image, or if you want to store a video, a cine loop, you can use it here as well.

Here is the full scanner.

It has a big screen, it has all of the stored images here, and it has the active screen up here where you are actually creating the image at the time.

Using Gel for Contact

We use a gel bottle because ultrasound doesn't go through air.

So if you put the transducer onto the skin without any contact material, without any gel, the air between the skin and the transducer would totally block any ultrasound information.

So you need to use gel between, you can use oil or gel between the transducer and the skin surface.

Probe Frequency and Image Quality

So here is two examples of scans, which is better.

Here we're using a curved array, relatively low frequency, three megahertz probe, 3 million cycles, a second probe.

And here you can see the patient, the fetal nose, the frontal bone.

You can see placenta, amniotic fluid is of course black.

And you can see part of the body.

Now that's a very nice image. Can you make it even better?

And the answer is yes.

If you use a higher frequency linear array probe.

Here you can see beautiful detail in the placenta.

You can also see the nasal bone, the frontal bone, the skin surface is much better detail than it was with the lower frequency probe.

So using a higher frequency probe, you're gonna get better finer detail.

And that's really, again, painting a detailed image allows you the information that you can make a better diagnosis.

Setting the Field of View

One of the problems that many people have is setting up the field of view correctly.

So here is a vaginal scan and you really don't know what you're seeing.

There's no recognizable anatomy here.

Whereas in this vaginal scan, you can see this structure here, which is the uterus and the central endometrial canal.

So what's the difference between these two images?

Well, this image, they have increased the field of view.

So you only have three centimeters field of view, whereas here you have six centimeters.

So if you have too large, too small, a field of view, you really can't find any landmarks and it becomes very difficult to figure out what you're doing.

But if you go down to six centimeters, now the uterus comes into view and it becomes easier.

So your field of view is very, very important to set correctly.

Comparison to CT and MR Scans

It's easier to read and appreciate CT scan and MR scans because you have external landmarks.

So in this particular case, this is a video, but here you can see the liver, the spleen, the stomach, and the very white bone, the vertebra body, the posterior elements, and alongside the ribs.

So you know where things are.

There's a black fat and the white skin.

So you have a pretty good idea of where you are.

And if you can also look at a video of this, as we sweep from the heart down to the pelvis, you can see that you're going through kidneys, you can see all the bones.

This is bowel and fat.

And as you sweep up again, and here we're going right down to the pelvis.

So they've done a complete sweep through the body to give you all of the available information.

So here you can see the heart, you can see the go back up to the heart there, then the liver on the right, on the left, anterior and posterior go to the liver.

And as you sweep down on the left, you now see the spleen posteriorly.

Now the kidneys come into view loops of bowel.

So because you have all of these landmarks on ct, it certainly makes it a lot easier to identify.

But we're talking about ultrasound, which is different than CT scan.

Now the ideal scanner is the bandsaw scan where you have the body here, but if you put it through a bandsaw and cut it, you then get exquisite detail of the liver, the stomach, and the spleen and the lungs.

Well, this is not something the patients really want to go through.

Certainly not more than once.

If you had all the landmarks, it's always easier.

So again, a para sagittal scan.

Here you can see the liver and the kidney.

It, it's easy if you have all the landmarks, but you don't in ultrasound.

And so that's always gonna be a problem.

Finding and Diagnosing Fluid (Ascites)

Well, finding fluid, that's one of the things that they say ultrasound is so good at.

But remember, it takes some training and it takes some skill.

It's not something that you just plop the probe down and there's the fluid.

Of course, in some people with extreme amount of ascites, that may be the case.

But here's a perfect example. Is there any ascites?

And if there is, can we put a needle into it and aspirate?

So here we have a large field of view, 15 centimeters.

You recognize the liver in this para sagittal scan.

Well, we'd be looking for fluid around the liver, but there's no fluid.

Why is there no fluid? Is this real or is this technical?

We're gonna try and look behind the liver.

In the hepa renal space, you don't see any liver there.

Well, you don't see any fluid there.

So is there fluid or is there not?

Let me show you the next sit, the next scan of the same patient.

Wait a minute. Here we have the liver.

With an irregular surface, you have black fluid in front of the liver between the anterior abdominal wall and the liver.

There's fluid.

How did we see fluid now where we didn't see fluid before?

First of all, we've taken our field of view.

We've changed it from 15 to eight and 10, eight to 10 centimeters.

We're using a probe, but we're not putting as much pressure on the anterior abdominal wall.

So before, what we were doing was we were putting too much pressure and we were obliterating the fluid, we're moving the fluid away.

And so all we saw was just tissue.

If you take the pressure off, there is a small amount of fluid.

And in fact, what you can do is you can put a needle under ultrasonic guidance through the peritoneum into the fluid and aspirate it.

Here you can see the probe is in line with the needle.

We're watching it go in.

It's going into, you only have about a centimeter here.

So if you do it blindly, you're gonna go right into the liver or you're gonna be in the anterior abdominal wall.

If you use ultrasound, you're gonna watch it go into the peritoneal cavity, and you're gonna be able then to aspirate the fluid.

For diagnosis, we use a 22 gauge needle.

And for most fluid, that's absolutely adequate.

You don't even need local anesthesia, but you've gotta watch the needle Going in with ultrasound.

Here's another patient.

They figure that he has a lot of ascites, and what they're gonna do is just do it blindly.

Well, as far as I'm concerned, tapping the abdomen blindly, if you have ultrasound available, is a terrible, terrible way to practice medicine.

Here they've tapped twice, they put holes in the abdomen and they got no fluid.

Then they call for ultrasound.

Well, they're putting it into bowel.

I keep telling these folks, if ever I'm unlucky to be a patient in the hospital, don't go sticking me with needles unless you are watching with ultrasound.

They sent the patient down, we get this every day.

They sent the patient down, failed taps. We do ultrasound.

We see beautiful pocket of fluid, put a needle in under ultrasonic guidance and pull the fluid out.

It's easy if you know what you're doing and you use the right tools.

Diagnosing Ascites Techniques

Now, how do you diagnose ascites?

Well, people have bulging flanks.

Like this guy, he must have ascites.

There's a technique called ottman where if you have fluid, you should be able to feel it on one side as you push on the other side.

And here we have, Here, we have such an example.

So you tap the hand on the left, you block any waves that's going across the abdomen, and you feel for it on the other side, Feeling for it to, you're feeling for it. Tap And feel, tap and feel, You're feeling for it to

An interesting technique.

But again, why use braille when you can see why try and, if you happen to be in a remote area and you have nothing else, you don't have ultrasound, of course, that's then you wouldn't be listening to this lecture.

But if you don't have ultrasound, then that may be the only way.

Unfortunately, our medical students are coming out with less and less clinical skills, certainly not the clinical skills that my father a gynecologist had 50 years ago because they're relying on technology.

And if you don't have technology, they don't have the background of their clinical skills to really do the job that's necessary.

Characterizing Fluid in Ultrasound

Now, once you find the fluid, you have to characterize it in this situation.

You look at it and you say, well, there's no echoes within it.

It's echo free fluid.

Maybe it's just simply plain ascites, plain clear ascites.

But here, the gain, the ultrasound gain is not high enough.

If you crank up the gain, you can see all of those low level echoes.

Low level echoes means puss or blood.

In the right clinical situation, this patient either has blood from bleeding or ruptured corpus lutetium cyst or puss in a patient who may have pelvic inflammatory disease.

So again, here you're not getting the information because you haven't set up the machine adequately.

Here, you've increased the gain.

You can see the particulate matter.

You now have a very important piece of information.

One other way of seeing the particles is to move them around.

And here you can see we're pushing on the probe a little bit, and you can see all of the little particles swirling around.

So you know for sure that this is particulate matter.

Again, what's the clinical situation?

Is this pus or is this blood? It's either or.

So again, answer the question, answer the patient's question, right?

Upper quadrant pain, mass fracture, whatever, answer the question.

That's your job. And it's the job not only of the physician, but also the sonographer.

The patient, the person who is doing the ultrasound has the ability to look into the body and examine the patient and answer the question.

Clinical Case: Right Lower Quadrant Pain

Here, a patient came down with right lower quadrant pain, 40-year-old male.

The question was testicular torsion. What's the question?

The question is, what's the cause of the right lower quadrant pain?

It's just a guess that the doctor thinks maybe it's testicular torsion.

Well, we started looking at the testicles and you see both testicles, they're normal.

They're normal in size, they're normal in echogenicity, they're normal in vascularity, normal blood flow.

No evidence of torsion in this particular patient.

If you go back and look at the x-ray, you can see a very, very faint density in the mid abdomen to the right of the vertebral body.

A CT scan is going to give you a superb image of the small focal density has the same density as bone.

So it's a small renal calculus where the referred pain was down to the groin, making people think that this was in fact a torsion of the testicle.

So this is a renal stone causing the patient's pain for the neck.

Scanning the Neck Vessels

Again, very superficial, very easy to examine.

Here is a cross-section of the neck, the artery and the vein, the jugular vein, the carotid artery and jugular vein.

We have two frames side by side in this frame.

We've compressed the neck.

The artery doesn't compress, but the vein compresses and the vein will compress.

If it's clear of thrombus of clot, if in fact there's clot in the vein, then it won't compress.

So a very simple technique to look for blood clot in the vessels, in the vessels of the neck.

Here is a sagittal view of the patient, not a transverse view.

So now we're looking at a long axis of the vein and the carotid artery.

And if you add color doppler that looks at tissue, that is moving.

So all the gray scale tissue is not moving.

But if you then add color, you add doppler.

So doppler appreciates movement of tissue and movement of fluid and allows you to characterize it.

So any blood flow moving towards the transducer is in red.

Anything away from the transducer is in blue.

And this is all moving towards the transducer.

So this is blood flow in the vein, in the internal jugular vein,

you can also put on a spectral doppler that gives you a readout of the pattern of flow.

And here you can see cardiac pulsation in the vein.

So doppler is very important.

2D ultrasound is very important, but remember, your job is answer the question.

Scanning the Thyroid Gland

The thyroid gland very common cause of problems.

They may feel a lump, the patient may have increased thyroid activity.

It's a very easy organ to examine because it's so superficial.

So here we're using a high frequency linear array probe.

Here you can see in long axis or sagittal view, the thyroid gland, muscles, strap muscles and skin and fat anteriorly

and on cross-section right through the middle of the thyroid gland.

Here you have the larynx that has air within it, and therefore, shadowing you have the isthmus of the thyroid that wraps over the larynx.

And then you have a relatively triangular shaped lower pole of the thyroid gland, lateral to it.

You have two echo free structures. What might they be?

The rounded structure is the carotid artery and the oblong structure is the jugular vein.

So beautiful view of the thyroid an absolutely normal thyroid.

Well, not everyone has a normal thyroid.

Here's someone who came in with a mass.

Is this mass a solid mass or fluid containing mass?

If it has fluid, the chances of it being tumor are very small.

If it's entirely solid and maybe has some calcification, the chances of it being tumor are much larger.

So here you see the mass without doppler.

You see the somewhat irregular solid part in the periphery and the black echo free central part.

If you turn on color to see if there's any vascularity in this tissue, you can see the vascularity.

And this here would be a nodule, a solid nodule, perhaps an adenoma that underwent cystic change.

And you still have part of the solid wall there.

So the chances of this being a tumor would be less than if it were entirely solid.

Scanning the Legs for Deep Vein Thrombosis (DVT)

And finally, let's just look at scanning of the legs.

Swelling of the legs. Pain in the legs again in the right clinical situation, makes you think of blood clots.

And blood clots on the leg can in fact lead to spread of the clot or breaking off of the clot going into the lungs and causing death.

Ultimately. Here is a patient who has lymphedema, who has very large legs.

The one on the left is much larger than the one on the right and it's red, it's infected.

So the question is, is there associated with this underlying cellulitis?

Is there also a clot in the vein?

Well, normally we would use a linear array probe to try and get at that information, but here you've got so much tissue, it's making it very difficult to see.

So on the sagittal view of the common femoral vein, the greater saphenous vein, they look fine.

And in fact, there's blood flowing through them in this situation, rather than going on top through that big emus leg, I went through some of the folds, using a curved array probe

because I needed to have more juice to get through that emus fat tissue.

And here you can see the vein here with the spectral flow showing that that vein actually is patent.

So that is the femoral vein.

And using a lower frequency, a broad transducer, I was able to identify that in fact, this is no evidence of DVT.

So this actually, well, maybe it's not the popeil.

It's either the popliteal or the femoral vein.

Clinical Case: Buttock Lump in Bodybuilder

And finally we have a situation where this patient, a 51-year-old, real bodybuilder injecting himself with lipid-based anabolic steroids and the doctor felt a lump.

And so what is this? Is this an abscess that he's got?

Well, here you can see he's got nice butts, but when he contracts his butt, you can see how this mass protrudes.

So the question is, is this infected or not?

Well, you look at the left butt and you can see this oblong cystic mass with low level internal echoes.

Would this be a lipid based fluid? Absolutely makes sense.

And in long axis and in sagittal view, you can see these two.

But what is this? It looks the same, but it's in his right butt.

So talk to the patient.

Have you ever injected into your right butt?

Oh yeah, I used to do that all the time.

And then it started to hurt. So I went into the left butt.

Well, both of these look the same.

Neither of them look infected.

The you, you talk to the patient, the answer to the question is he's injecting himself with lipid-based fluid.

These are just simply large pockets of fluid, no evidence of infection.

So answering the question, he came in with a butt lump.

Was it an abscess?

It was fluid filled on the left, smaller on the right.

The answer is it's just lipid based steroids.

And the one on the right is resolving over time the solution is weight for the one on the left to also resolve.

Conclusion

Well, everything is easy if you know how to do it.

So this is one a ultrasound.

I hope that I've shown you how fabulous a tool it can be if used properly by someone who has appropriate amount of knowledge.

Thank you very much.