0:00

All right.

0:01

Um, hi, I'm Laura Avery.

0:03

I am an emergency radiologist at

0:05

Mass General, and I teach medical students as well.

0:08

So sometimes my material gets back to the basics,

0:11

but, um, I think that's something that's really

0:13

helpful for everyone at every stage of their career.

0:16

So I hope that these cases are fun and interesting.

0:21

Um, my teenage children, we're on vacation right

0:23

now, have been told to stay off the internet, um,

0:27

so that I can use it for this lecture.

0:28

But if you hear screaming, it might be a child

0:31

having withdrawal seizure from the internet,

0:33

because goodness knows quarantine has resulted in

0:38

the lack of any parental expectations on screen time.

0:40

Anyway, um, let's see here.

0:45

All right.

0:45

So, you know, obviously, this is historical

0:47

in nature, but this is how medicine was

0:49

done for centuries and centuries,

0:51

and now we've moved on to the current format.

0:53

So, um, this is a, uh, Zoom lecture.

0:57

I hope it is, um, somewhat interactive, but

1:01

it may take a little bit of, um, you know,

1:04

trying to, with one another for that to occur.

1:07

Uh, and please put anything in the chat,

1:09

talk to each other, um, look at the cases and

1:11

try to be, uh, as interactive as possible.

1:15

Okay.

1:15

So we're going to start with the good old KUB here.

1:18

Here's a 72-year-old who presents with

1:20

nausea and vomiting, a supine and upright view.

1:24

Typical, um, centrally located loops of bowel

1:27

with the valvulae conniventes folds going across,

1:30

consistent with a small bowel obstruction.

1:32

You have no colonic air here.

1:33

So this is a beautiful appearance of a

1:35

small bowel obstruction, classic on a KUB.

1:39

So what are some causes for small bowel obstruction?

1:41

We learned these in medical school,

1:42

adhesions, adhesions, adhesions, hernias,

1:46

inflammatory bowel disease such as Crohn's,

1:49

some malignant tumors can sometimes cause,

1:51

um, obstruction, especially metastasis.

1:53

And the fun zebra of gallstone ileus is

1:56

always in every medical student textbook.

1:58

Well, you know, in this case this

2:00

is an inguinal hernia, so I'm gonna

2:03

go into hernias as a cause for

2:07

obstruction because I like to say inguinal

2:09

hernias or hernias get Lori home faster.

2:12

So those get me home faster.

2:14

So on all of my small bowel obstruction

2:16

cases, I'm always looking for hernias.

2:18

It's just so satisfying, cause

2:20

for small bowel obstruction,

2:21

everyone has an action plan and

2:23

it is the fastest diagnosis.

2:26

So we're going to go into a number of hernias today

2:28

with a bit of closed loop obstruction as well.

2:31

So if you're doing this in a delayed

2:32

fashion, I suggest you pause me.

2:35

I'll pause, um, and review cases one through eight.

2:39

You can just write down, just jot

2:41

down your thoughts on each of them.

2:42

Some of them have a very small finding.

2:43

Some of them have a more significant

2:45

finding, but I think it's fun to have

2:46

a chance to look through those cases.

2:47

Um, they will be in the, uh, in the DICOM

2:51

viewer for, um, the MRI online individuals.

2:54

Okay.

2:55

So here we have three patients,

2:57

all of whom have groin hernias.

3:00

Patient A, Patient B, and Patient C.

3:02

Which patient is at greatest

3:04

risk for bowel strangulation?

3:08

Well, let's look at these hernias.

3:11

Okay, so we have three patients.

3:13

Um, we are at the level of the pubic tubercle.

3:17

Um, this is the symphysis pubis here.

3:18

The lateral margin of the symphysis pubis is

3:21

oftentimes referred to as the pubic tubercle.

3:23

Alright, so how we look at the groin

3:25

hernias is that we draw a horizontal

3:27

line from the pubic tubercle laterally.

3:30

Okay.

3:31

At all levels.

3:32

Now, if the groin hernia comes out anterior to

3:35

that line, we think this is a typical inguinal

3:38

hernia, your direct or indirect inguinal hernia.

3:41

If it comes out posterior to that line,

3:44

then we're dealing with a different type of

3:45

hernia, either a femoral or obturator hernia.

3:48

Here we have a femoral hernia adjacent to the femoral

3:50

vein and artery, and the obturator hernia deeper.

3:53

But let's go to each, um,

3:55

hernia that we're about to see.

3:57

Alright, so defining the typical inguinal

4:00

hernia, this has been kind of flipped around.

4:02

So this is lateral, this is

4:03

medial, this is direct to sheath.

4:05

We're going to talk about the

4:05

indirect and direct inguinal hernias.

4:08

Those inguinal hernias are referenced

4:10

to how the hernia extends, um,

4:13

relative to the epigastric vasculature.

4:16

Alright?

4:17

The inguinal hernia comes out.

4:18

The indirect inguinal hernia, pardon me,

4:21

comes out lateral to the epigastric vessels

4:23

and extends down the inguinal canal.

4:25

Usually in kind of an oblique fashion.

4:27

These are usually your congenital hernias.

4:29

You'll see the congenital indirect hernias.

4:31

Now, people sometimes acquire the

4:33

direct hernias, which are medial

4:36

to the epigastric vessels in what is

4:39

referred to as Hasselbach's triangle.

4:41

You may remember this from your medical school

4:43

days that was defined by the lateral margin being

4:46

the epigastric vessels, the inferior margin, the

4:49

inguinal ligament, and the linea semilunaris as

4:52

the lateral aspect of the rectus femoris muscle.

4:55

This is an old image from Gray's

4:57

Anatomy to help us remember that.

4:59

Um, anatomy.

5:00

So here's a patient who's 58

5:01

years old, nausea and vomiting.

5:03

No doubt that they have small bowel obstruction.

5:05

You can see those very dilated

5:06

fluid-filled loops of small bowel.

5:07

I have my arrow there pointing

5:09

to the epigastric vasculature.

5:12

And as we come down, we're going to see

5:14

those bowel loops come anterior to the pubic

5:17

tubercle and they are coming out lateral.

5:21

To the epigastric vessels.

5:23

This is atypical, indirect inguinal

5:25

hernia coming in that oblique

5:27

fashion, um, into the inguinal canal.

5:30

I see 'em all the time.

5:32

That's like bread and butter, right?

5:34

Here's a 62-year-old.

5:36

He has some dilated loops of small bowel.

5:38

Not that dilated, but don't

5:39

worry, it's a pretty illustration.

5:41

As we come down, we're going to

5:42

see those epigastric vessels.

5:44

And we're going to see that those bowel loops on

5:47

both sides, bilateral, um, he must be a heavy lifter.

5:50

Maybe he's doing too much CrossFit.

5:51

Let's be clear, that's not good for your body.

5:54

Um, coming down medial to the epigastric

5:57

vasculature, and on the coronal, you'll see

6:00

them descending through Hasselbalch's triangle

6:04

in a very vertical manner.

6:07

All right.

6:08

So those are your typical inguinal hernias.

6:10

Honestly, most people don't even

6:12

define the two from each other.

6:14

Uh, it's just kind of fun.

6:15

I think to tell the surgeons which, um,

6:18

inguinal hernia you have. You have your

6:19

indirect, lateral to the epigastric vessels.

6:21

You have your direct, which is

6:23

medial to the epigastric vasculature.

6:25

And then a really fun one is when you have both.

6:28

So this is a direct, fat-containing hernia

6:31

coming down and an indirect hernia.

6:33

You can see that they kind of cross the

6:34

legs and that is referred to as a pantaloon

6:38

hernia, um, such as these big pantaloons here.

6:41

So, um, that's just anterior to the pubic tubercle.

6:44

Now let's go on to, uh, the more complex hernias

6:47

because we want to make sure that we don't,

6:48

um, call these your typical inguinal hernia.

6:51

We want to give the surgeons higher definition because

6:54

the need for surgery and or, um, intervention may

6:57

be, uh, quicker or more in need for intervention.

7:01

It can be harder to decompress these, um, physically.

7:04

So here is a case again of dilated loops

7:07

of small bowel fluid-filled coming through.

7:09

You can see my arrow there.

7:10

You have the femoral artery, the femoral vein, and

7:13

the bowel here coming through the femoral canal.

7:16

And this bowel lies lateral.

7:20

Posterior, pardon me, to that line

7:22

we drew from the pubic symphysis.

7:24

This is a very typical appearance of a femoral hernia.

7:27

Look as it squishes that femoral vein.

7:31

Very, very typical appearance.

7:33

We like to refer to this as

7:34

the femoral vein comma sign.

7:36

That's when you actually see mass effect upon

7:38

the femoral vein, as opposed to the contralateral

7:40

side, where it's a nice rounded vessel.

7:42

I really do suggest using that as one of

7:43

the signs of a femoral, um, uh, hernia.

7:48

Okay.

7:48

Number four, it's to complete the players.

7:51

Here we have dilated loops of small bowel.

7:53

Definitely.

7:54

Um, you know, small bowel obstruction.

7:56

And as we come through, we're going to

7:58

see the small bowel, uh, loops extending

8:02

through the obturator foramen.

8:04

Here and lying posterior to the pubic

8:07

tubercle, just like the femoral one did.

8:10

Um, but in this case, rather than being adjacent

8:12

to the femoral vein and causing a mass effect upon

8:14

the femoral vein, this loop of bowel is actually

8:17

seen posterior to the pectineus muscle here.

8:20

So that's your landmark as the pectineus muscle.

8:22

And that has gone through the obturator foramen.

8:25

Which is a pretty unusual hernia.

8:27

I've only seen a handful of these during my time in

8:30

the emergency, my 15 years as an emergency radiologist.

8:34

But because they are such a high risk of

8:37

strangulation and mortality, they are really

8:39

something to consider highly on your really look for.

8:44

So here we have our three hernias: your

8:46

inguinal, your femoral, your obturator hernia.

8:49

Again, we're going to remember that the femoral

8:50

hernia causes mass effect upon the, uh, femoral vein,

8:54

called the femoral vein comma sign, and is anterior

8:58

to the pectineus muscle, whereas the obturator

8:59

hernia is posterior to the pectineus muscle.

8:02

So, which patient is greatest risk of bowel

8:05

strangulation? That would definitely be the

8:07

obturator hernia. They're very uncommon,

8:09

um, but have a very high mortality rate.

8:12

All right, so now we're just going

8:14

to move through some companion cases.

8:16

Um, I'm willing to show you my misses, so that's,

8:18

you know, kind of humiliating, but that's okay.

8:21

This case, I did not get correct.

8:23

So I was in the ER, one of those busy nights,

8:24

tons of cases were coming my direction.

8:26

Um, the technologist came in and said that she

8:29

had a two-month-old with an inguinal hernia

8:31

containing, um, bowel, and I was like, okay, fine.

8:34

You know, I, I, to be clear, they're almost always

8:36

right, so I would never, ever question our technologist.

8:39

Um, and I dictated as such, but this is an unusual

8:42

case, and I think if you're not knowledgeable about

8:45

this entity, you could come down the same way I did.

8:50

And now that I know about it,

8:52

I want to pass it on to you.

8:53

That is my goal.

8:54

So here's a two-month-old female

8:56

with a palpable inguinal hernia.

9:58

You see this, um, situation here coming through

10:01

the, uh, on a sweep through the inguinal region.

10:06

But look at this closely.

10:07

Does this look like bowel to you?

10:09

It looks a little unusual.

10:11

Um, so let's make it even bigger.

10:12

There's nice flow in it.

10:13

There's nice blood flow in it.

10:15

Um, so it's not like a septated fluid collection.

10:18

But it doesn't look like bowel either.

10:22

This, my friends, is a herniated

10:24

ovary through the canal of the neck.

10:26

This can happen in, um, in babies and

10:30

female babies, uh, usually, um, within

10:32

the first couple of months of life.

10:34

Um, and that is because it's similar

10:36

to the indirect hernia, the process

10:39

vaginalis with the testicles descending.

10:42

Um, the round ligament allows the possibility for the

10:45

ovary to descend down this, um, canal of the neck.

10:49

Uh, and result in, um, it can even result

10:52

in ovarian torsion or incarceration.

10:55

So this is something to be aware of.

10:57

If we look back here and instead of bowel,

11:00

this really does look like an ovary.

11:02

Um, there's multiple little tiny

11:03

fluid-filled follicles within it.

11:05

Um, bowel and an inguinal canal in a similar age group

11:08

patient should have disappearance with the echogenic

11:11

submucosa of bowel, um, and also should peristals.

11:15

So, uh, I think knowing that an ovary can

11:18

herniate through that location is really important.

11:20

I don't do as much pediatrics, so that was new to me.

11:23

Um, and being aware that, uh, you know, this could be

11:27

on your differential of inguinal hernias in a neonate.

11:32

Okay, case number six.

11:35

Here is a 78-year-old, um, with nausea, vomiting.

11:41

Complains of right-sided leg pain.

11:43

Normal.

11:47

Let me just look at the, sorry, get this out of here.

11:51

Um, all right.

11:53

Uh, so here we have dilated loops of small bowel,

11:57

and if I can draw your attention, we actually

11:59

have a loop of small bowel herniating posteriorly.

12:03

in this location.

12:04

Let's make that bigger.

12:06

This is a loop of small bowel herniating

12:07

here through the sciatic foramen.

12:10

Um, that's why the patient has, uh,

12:12

pain down the posterior leg, um, because

12:15

this is a sciatic foramen hernia.

12:17

Now this is pretty uncommon.

12:18

This I've only seen it like twice with

12:20

bowel, but actually in the literature, it's

12:22

written up that, um, women can have their

12:25

ovary herniate through this location and it

12:27

can result in, um, cyclical radiculopathy

12:31

of the leg when that ovary, um, uh, cycles.

12:34

So it's, it's a known, um, uh,

12:38

foramen for which bowel can, bowel or

12:41

ovaries can herniate, which

12:42

I think is very interesting.

12:44

Um, and this is indeed the sciatic

12:45

foramen hernia on the coronal.

12:48

You can see it coming through here as well.

12:50

We're going to bring up an image, um,

12:52

from, uh, Gray's Anatomy showing that,

12:55

uh, sciatic foramen as a possibility.

12:57

So that's, um, an unusual hernia, but

12:59

I like to kind of show the typicals

13:01

and then like a little unusual variant.

13:03

Someone asked here if it's important to

13:05

mention small fat-containing inguinal hernias.

13:08

To be clear, I don't.

13:09

Um, I figure in the ER, unless it's causing

13:12

problems, um, I don't really mention this much.

13:17

Have to get through stuff, right?

13:18

Um, so here is case number seven.

13:23

Incidental finding.

13:25

Okay, we're going to switch to

13:26

the left side of the patient.

13:27

We're going to make it even bigger.

13:28

All right.

13:29

So we've gone through all these hernias.

13:31

We've talked about this groin location.

13:33

We've talked about the pubic tubercle drawing the line.

13:36

This one's posterior to the pubic

13:37

tubercle, but this is weird, right?

13:39

Um, there's fluid here and it's lateral to

13:42

the femoral vessels and vein and artery.

13:46

Um, You know, this is not bowel.

13:49

I've had a number of residents want to call this a

13:51

necrotic lymph node, um, have a hard conversation with

13:54

the patient and/or biopsy, but I want to highlight this

13:57

kind of funny appearance of a groin fluid collection.

14:01

Um, and when you bring it up vertically, you

14:03

can see that it goes along the iliopsoas muscle.

14:05

This is iliopsoas bursitis.

14:07

This is something, um, that we see, uh, infrequently,

14:11

but on occasion, and it is just fluid within

14:15

the bursal sac of the iliopsoas tendon.

14:18

They can be really big and very dramatic.

14:21

So if you see a fluid collection there,

14:24

don't think of it as an inguinal lymph node.

14:26

See if you can trace it in the iliopsoas where it attaches

14:30

to the lesser trochanter, um,

14:32

and watch that location.

14:34

Also, in patients with trauma, look at that muscle.

14:37

Sometimes it avulses in little, um, in elderly

14:40

patients kind of spontaneously, and you'll see a

14:43

nice little bubble of muscle in that groin location

14:46

with some stranding, and it can be, uh,

14:48

noted as a spontaneous iliopsoas tendon rupture.

14:52

It's on your spontaneous tendon rupture differentials.

14:57

Okay, so here's case number eight.

15:01

Here we have a 28-year-old with

15:03

inguinal pain, fever, and chills.

15:05

We're going to come down and through

15:08

the inguinal canal, we're going to see

15:09

this little tiny blind-ending tube.

15:13

Let's look at it on coronal because it's going

15:14

to well see that it comes off of a slightly

15:17

inflamed, um, base of the cecum, right?

15:20

Some people have called this

15:21

the sickle bar sign.

15:23

I think that's an old sign from when,

15:25

um, can you imagine those people?

15:26

Uh, they used to work up appendicitis

15:28

with, um, contrast enemas.

15:31

Uh, thank God for CT.

15:34

Um, but that was just an indication on a

15:37

contrast exam that there was inflammation

15:39

at the orifice of the appendix.

15:42

And here you can see the nice appendix

15:43

coming off the base of the cecum and

15:46

coming down into that inguinal canal.

15:49

And here we go.

15:51

That is the amyand hernia.

15:54

Um, at Mass General, you know,

15:57

everything's named after everything.

15:58

Uh, so we like to say that those

15:00

are the dead white guy names.

16:02

Um, we like to call it the DWG.

16:03

So this is a DWG hernia.

16:06

Um, and this is an Amyand hernia, which is

16:09

an inguinal hernia containing the appendix.

16:12

The first, um, successful appendectomy in

16:16

1735 was actually performed, uh, by, um,

16:22

Dr. Amyand, uh, on a patient who had a 17-year-old

16:25

or 11-year-old, pardon me, who had

16:27

appendicitis into his inguinal canal.

16:29

So that was very lucky at the time since more

16:31

invasive surgeries would not have been successful.

16:35

Pretty impressive.