Pitfalls in Obstetrical Ultrasound – When You Think Something is Wrong - SD

Introduction

I am Dr. Beverly Coleman, professor of radiology at the University of Pennsylvania Medical Center in Philadelphia.

And today we're gonna discuss obstetrical pitfalls when you think something is wrong, Pitfalls and obstetrical ultrasound when you think there's something wrong.

Today I'm going to try to focus on six common ultrasound findings that you often encounter when evaluating second and third trimester pregnancies.

These include, as you see listed here, cord plexus cyst, ventricular magaly, echogenic intracardiac focus, prominent thymus, mild renal bowel, ectasis and echogenic bowel.

Choroid Plexus Cyst

We'll begin with cord plexus and one of the first questions we should consider is, is the finding real or not real cord plexes is a very common occurring in approximately 1% of all second trimester scans.

They may be single or multiple clustered unilateral or bilateral and even septate.

We know that these tiny fluid collections result from the enfolding of the neural epithelium, which trapped CSF fluid in cells.

Normally the cord plexus is heterogeneous with tiny little lucencies and it is prominent in the first trimester but begins to recede thereafter.

Here's an example of a case and you can see that the sonographer has measured the entire area of the ventricles posteriorly.

Do you really see true cord plex assist?

Are these pseudocysts and if so, is this an isolated finding or not?

This happens to be the daughter of one of our sonographers who does detail obstetrical sonography.

And when she saw the cord plex cyst in her daughter's skin, she became really upset and we talked about whether there were other interventions needed such as amniocentesis.

And after doing a thorough check of the pregnancy, we decided the cord plexsis were isolated and of no particular concern.

And on the screen in front of you is Anya the result of that obstetrical examination.

Here's another case of blaw battle, bilateral choroid plexus.

You can see that there are discreet tiny anti coic areas within the choroid plexus bilaterally.

Here is an example of how we measure, measure these tiny cysts.

The cursors should be pasted inside to inside and it should be a discreet sonar lucency that you can describe in more than one plane.

And here we can see the measurements, two adjacent tiny cysts, one in the five millimeter range and the other in the three millimeter range.

A true cord plexus cyst is as you see outlined on the prior scan, the size threshold range from very tiny at two millimeters up to 14 millimeters.

The criteria for diagnosing a cord plexus cyst is that in theory they should be greater than 2.5 millimeters in early pregnancies before 22 weeks and at least greater than two millimeters thereafter.

Otherwise, these tiny lucencies should probably not be dictated as a choroid plexus cyst.

There is no follow-up indicated in these cases since in approximately 90% of the cases they will be all gone by 26 weeks and virtually 100% will be gone by about nine, 28 weeks of gestation.

Here's an example of another patient where there are a bilateral cord plexus cysts that are large in the six to eight to seven millimeter range.

Large chlor plexus cysts are more worrisome, but only if they're greater than a centimeter in diameter.

Isolated cysts usually occur in the globus.

As I stated before, they're often transient and there's been no real correlation with laterality.

What we get excited about is that in a very small number of cases, less than one in 400, patients that are low risk will have a significant risk of aneuploidy.

We know that there is a known association with cord plexus cyst with Trisomy 21 and that's what we are most concerned about.

The majority of those cases, however, will have lots of other abnormalities associated with the finding of the CPC.

If there is a CPC with another minor marker, this increase increases the patient's a priority risk about 20%.

And if there is a major ultrasound marker about 50%, an isolated choroid plexus is has no real association with Trisomy 21 unless there are other markers seen.

Here's an example of a patient who presented with a question of double bubble and the issue was, in the finding of duodenal atresia, what are other findings?

Is it true atresia or could it be stenosis?

And is this family at risk?

And on the outside scan, the absence of the nasal bone was missed and a very tiny involuting cord plexus cyst is still, present unilaterally in the right CPC area.

And this patient had a proven diagnosis of Trisomy 21.

So what to look for if we see an isolated cyst, whether, benign, bilateral or unilateral, we'd like to watch the hands and feet.

This is the one time you wanna clearly do a detailed evaluation of the heart looking at the outflow tracks and look at the fetal face.

Here's an example of a patient with isolated cord plexus s.

When we look at the upper extremities, we can see that the hands are in fixed extension, with no evidence of fisting, which is what we would worry about in a case of trisomy 18, which is the proven diagnosis in this case.

And if you notice on the 3D, there's active fetal movement, but the hands are persistently fisted because this is a fixed neuromuscular abnormality, this fetus had bilateral very large choroid plexus cyst as well as congenital heart disease with the large VSD that you see here.

Potential Pitfalls and Mimics of a True Choroid Plexus Cyst

So what are the potential pitfalls and mimics of a true cord plexus cyst?

Well, there could be a pseudocyst where it does not fit the size criteria.

There can be mild ventricular magaly actually masses or hemorrhage in the region of the chor plexus.

Here's a patient who has a very heterogeneous appearing chor plexus and notice that their tiny little lucencies, some of them linear, others oblong and ill-defined, but this represents a case of pseudocyst and these tiny echogenic spaces should not be measured and reported as a true cord plexus cyst.

This is a case where there is a tiny little cord plexus cyst, less than three millimeters, but on the contralateral side there is a punctate echogenic focus.

And here you can see that here on the left, this is a patient who had focal grade one, germinal matrix hemorrhage with C plexus hemorrhage on the left and the tiny cord plexus cyst on the right, a choroid plexus papillo.

Generally these tumors are very large echogenic masses.

Here you can see an example of one and there are tiny little cystic spaces but unrelated to the finding of a cord plexus cyst and notice that this tumor has vascularity, which you should never see in the setting of ahor plexus cyst.

Ventriculomegaly

Now let's move on to ventricular magaly.

I think the real issue when there's a question of what is going on with the ventricles is, is there true enlargement or could this be a variant of normal?

It is important to make sure we always make the measurement of the ventricles from the internal walls.

And in the true standard axial plane, normally as you know, the diameter should be about seven to eight millimeters and anything greater than or equal 10 millimeters is of concern.

In addition, if there is a dangling cord plexus where the gloma is more than three millimeters separated from the medial wall, even though the measurements are not exactly at 10 millimeters, it can be caused for concern.

Similar to cord plexsis, ventriculomegaly is a common finding on second and third trimester examinations.

And our job as sonographers is to determine the etiology and whether this is a finding of clinical significance and if so, how severe.

We categorize ventricular magaly as mild using a measurement of 10 to 12 millimeters, moderate 12 greater than 12 to 15 millimeters and severe greater than 15 millimeters.

Here's an example of a case that turned out to be proven idiopathic ventricular magaly.

We can see that the ventricle measured inside the inside at the region of the gliomas is just over the 10 millimeter range.

And here's another patient where we can see the measurement is less than the 10 millimeter range At nine millimeters, however, there's a five millimeter separation of the gloss of the choroid plexus, which is non-dependent and shifted away from the medial um, ventricular wall.

So what to look for when we are assessing a patient for possible ventricular magaly, we wanna look carefully at both lateral ventricles and the areas of the ventricles, including the germinal matrix and chlor plexus for possible hemorrhage and the dependable lining of the ventricles.

We wanna check the third and fourth ventricle and examine all of the midline structures.

Here is a case of proven idiopathic ventricular asymmetry.

When the ventricles measure differently in size, more often the left is larger than the right, as in this case about eight millimeters compared to three millimeters, both within the normal range.

However, you wanna always compare that by using different views.

So this is a coronal view showing the asymmetry that persisted.

We have a normal third ventricle, normal midline structures, beautiful corpus callum, Cajun septum, lucidum, and cavan verge.

This was a male fetus and they tend to have more ventricular asymmetry compared to females and their ventricles often tend to be slightly larger.

So for further evaluation we wanna characterize the severity of any case that we diagnose as true ventricular magaly.

Is this mild or borderline enlargement, in which case 95%, 90% may be idiopathic with a 4% incidence of chromosomal abnormalities, particularly trisomy 21 and 18.

We wanna determine the level of obstruction if that is indeed obstruction present.

Assess the gender specifically because of the male female ratio of mild ventricular magaly, which is about three to one.

We wanna see if we feel that this could be idiopathic because approximately a third of those cases will resolve.

And in doing our detailed and further assessment, we wanna look for the causes of ventricular magaly, which are all of the entities that you see listed here.

Here's an example of asymmetric cerebral ventricles where we can see that the right ventricle is slightly larger than the left and that persists on these coronal images.

And if you notice, there is sort of heterogeneity and lobular of the region of the germinal matrix.

This is a very early grade one germinal matrix hemorrhage, which was proven at birth.

Here's a case of mild ventricular magaly where the ventricular atrium actually measures less than 10 millimeters at nine millimeters.

However, there's more than a three millimeter deviation of the choroid plexus from the media of ventricular wall.

And if you look here on the coronal views, you can see the mild prominence of the ventricles posteriorly.

Looking further for etiology, we can see that there is inferior verian, hyper hypoplasia with verian tissue here, but communication of the cistern or magna to a mildly dilated fourth ventricle.

Pitfalls and Mimics of Ventriculomegaly

What are the pitfalls and mimics of ventricular magaly?

Well, we can think the ventricles are dilated when they actually are not due to artifact in the far or near field.

We can see other cystic lesions in the cranium and misconstrue those as representing ventricular magaly and these can be normal or abnormal structures.

And finally, a large cord plexus cyst can be confused with the dilated ventricle.

Here's a patient who, looks on this oblique view as though there is a dangling cord plexus, but when we line up the brain and do the standard true axial view, you can see the ventricles barely measure seven millimeters.

And this is pseudo ventricular magaly.

Here's a case that was referred for a possible dilated third ventricle and this is the region of the Cajun septum lucidum that you can see here that extends back and in to the region of the Cavan Virga.

Here on the sagittal view we can see a normal corpus callosum, cave septum, lucidum and cavem virga all normal midline structure.

So this is not a true finding.

The cavem velum insum cyst, this is a tiny little focal cystic area, which is a variant of normal and of no clinical significance.

It was referred in this patient as a possible dilated third ventricle.

We can see our normal corpus callosum and midline structures.

This is an instance of large cord plexus cyst and here we can see that the cystic area is not actually the ventricle.

This was referred in as ventricular magaly and the stenographer failed to notice that this is the region of the cord plexus here.

That's echogenic.

And if you scan back just a little farther, we can see behind the gliomas of the choroid plexus, the ventricle actually measures seven millimeters.

Another case of very large bilateral c plexus cyst confused as ventricular magaly.

As we do a further detailed evaluation to look for the etiology, we see that the there is myo schisis with a flattened spinal defect without a measurable sac, the cord is tethered to the site of the defect.

And when we turn transversely at L five, we can see that there's wide splaying of the vertebral, processes in a patient with again, an open spinal defect.

Echogenic Intracardiac Focus

Let's move on to echogenic intracardiac focus.

Another aggravating feature that can be seen on ultrasound examinations.

And the question is, is this of significance or not?

EICF can be seen in up to 8% of second trimester scans.

There are ethnic influences and it has been reported that these can be more common in those of Asian or African descent.

We should use specific criteria to make the diagnosis.

And again, measurements are critical.

These ought to be tiny echogenic foci that don't really shadow and measure less than three millimeters.

By definition, they ought to be bright as bone, they should be reproducible and visible in multiple planes and typically a best seen on the axial view with the apex pointing, forward in the fetus lines supine.

Here's an example of bilateral ventricular EICs, a tiny one in the right ventricle and the left ventricle.

Different patients, you can see that the measurements are under three millimeters in all of these cases.

What are we looking at when we see these tiny structures?

This is represents papillary muscle mineralization and pathologically these have been evaluated and shown to be fibrous tissue aggregates with punk tape dystrophic calcifications.

They're most commonly seen in the left ventricle, approximately 78% of the time 18% in the right ventricle and 4% of the cases may be bilateral.

These can be multiple.

Our solitary echogenic foci Here is an example of a scan that was done in my godson's wife who was pregnant.

And I received a desperate phone call with tears in the whole works because of the finding of an EICF and an umbilical cord cyst and possible my ventricular magaly.

And here we can see that there is a punctate, tiny echogenic focus in the left uh, region of the left ventricular outflow tract.

Here is a normal ventricle that's barely seven millimeters with some asymmetry five millimeters on the other side, but not true asymmetry 'cause it's not at least three millimeters different and this turned out to have a normal outcome.

Here is my godson's, son now and this is Beko coming to visit me in my ultrasound laboratory at the University of Pennsylvania.

Here is a clip again of a case that was referred in as possible EICF and you can see that there's more than one tiny echogenic reflector on the cynic clip.

Some are real or not real and the ones that are true have to be again as bright as bone and persistent and seen in more than one plane.

And the important thing is to look for other associated abnormalities.

There is a known association with aneuploid and EICF can be seen in trisomy 21 and 13.

There can be a 1.8 times increased risk over a priority risk for patients with Trisomy 21.

And these EI Cs can be seen in 18% of down syndrome fetuses, interestingly, much more common in trisomy 13 fetuses.

However, we don't encounter trisomy 13 cases as often as we do trisomy 21 cases.

In actual fact, three to 5% of eulo fess fetuses may actually have EICF.

If there is a finding of EICF along with hypoplastic left heart syndrome, this can be very concerning for trisomy 13 and we wanna look for other anomalies such as musculoskeletal findings in those patients.

The important thing is to differentiate the routine patients who should not be worried, from those patients who may need to go on for further workup.

If you have a patient less than 35 years old with an isolated EICF, in theory there's basically no risk in these patients and no further workup is really recommended.

There is an increased risk when the EICs are large and bilateral and there are other signs associated.

Here's an example of a patient with proven trisomy 21.

Here we can see the heart with bilateral pleural effusions.

There's scalp edema, a hypoplastic nasal bone and a very shortened femur lane.

But interestingly, this patient did not have an echogenic intracardiac focus.

So what do we wanna do when we are doing this examination for this finding?

We wanna scan from multiple angles.

We wanna watch closely in real time because interestingly, EICF may also be a possible marker for structural cardiac anomalies.

So in these cases we wanna spend the extra effort to look for other parts of the cardiac anatomy, including the inflow and outflow tracts, the aortic arch, the ductus arch, and so on.

Here's an example of bilateral EICF in the finding of tetrology of fall flow and I believe this clip shows an excellent demonstration of the overriding aorta that we can see here.

Notice that in this plane you can, looking at the overriding aorta, we don't really see the e ICFs as well, but here is another plane where we can see clearly the, tiny echogenic foci which we saw in more than one plane.

This was a proven case of 22 Q deletion and a patient with bilateral, EICs and proven tetrology of fall low.

Normal Structures that Can Mimic an Echogenic Intracardiac Focus

Are there normal structures that can mimic an echogenic intracardiac focus?

And what you see before you is a list of findings including the moderator band, various valves, various calcifications either on the septum or on the myocardium, and even echogenic structures outside the heart can be confused as an EICF.

Here we can see a tiny echogenic focus that's not really as bright as the adjacent rib or the sternum.

This is a papillary muscle reflector and not a true ICF.

Here is a tiny reverberating reflector off, the ventricular wall in a case of right ventricular hypertrophy.

Again, not a true EICF.

This is a pseudo EICF, which is an echogenic area that is associated with a valve and a spec reflector there and not a true EICF.

This is a patient who was referred for bilateral EICF and here you can see that there is a more coarsened uh, shadowing, and larger than expected echogenic focus.

A tiny EI set CF in the left cardiac ventricle there, but this is actually subdiaphragmatic right at the level of the diaphragm and it represents one of those tiny echogenic foci that you may see in the upper abdomen, either on the right or the left quadrants generally of no clinical significance.

Again, as an isolated finding.

And this is near the area of the heart, but clearly outside of any of the cardiac chambers, this is a really rare and unusual case of idiopathic infantile arterial calcification.

And this case there were multiple echogenic areas that you could see in the heart on real time, which we can see here.

The heart was enlarged with pericardial fusions.

You can see reflectors off of the base of the aortic root and off of the regions of the valves, but also notice that there is extensive calcification of the abdominal aorta down into the region of the pelvis.

Here is the area of the iliac crest and notice that there's extensive vascular calcification throughout both kidneys.

Prominent Thymus

Let's move on now to a prominent thymus.

The question here is, is this really a mass lesion or something to be concerned about?

The thymus, as you know, originates from the third brachial cleft descends into the mediastinum at about 12 weeks.

Can actually be seen on relatively early scans at 14 to 18 weeks.

But generally it becomes a problem and can be confused as a mass when you're doing patients, later in pregnancy, in the late second and early third trimester.

Here's an example of a patient who has a normal thymus and here you can see between the areas this hypo coic sort of marbly appearing structure in the anterior mediastinum.

No true mass effect on the heart or the lungs, but depending on how you rotate the transducer and obliquely scan it can appear prominent.

This patient was sent for an outside doses diagnosis of right CAM and here we can see that there's a discreet mass here, but it is an anterior mediastinal mass, not a right chest mass arising from the lung parenchyma here is a normal lung.

Here's the thymus and here is a normal heart.

The contralateral left lung.

This is simply a normal thymus gland that was visualized later in pregnancy and confused as a parental mass.

The best way to see the thymus again is on that four chamber heart view.

When the fetus is supine with the apex up, towards the transducer, it again lies anterior to the great vessels.

There are two lobes when you're scanning patients in the mid second trimester or earlier.

Generally it can be sort of echogenic or iso coic to the lungs but becomes more and more hypo coic over time.

And by the time you get to the third trimester, it's clearly hypo coic relative to the normal lungs.

And here you can see a hypo coic thymus in a well-developed, fetus greater than 27 weeks.

Here's a more echogenic lung tissue.

And again, this should not be confused as a mass lesion when we do a transverse or axial view through the upper mediastinum.

Again, here is a thymus in the midline anterior to the heart and the great vessels a totally normal finding and it should not be of concern.

Other Lesions that Can Mimic the Thymus

Are there other lesions that can mimic this appear?

A goer typically is higher in the neck and not in the region of the mediastinum tends to be vascular.

Intracardiac masses can occasionally be confused, but a congenital cystic adenoid malformation as we previously discussed, arises within the lung parenchyma and should never be confused, as a thymus and the thymus should not be confused as a C cam.

Here's an example of a patient who has a mass.

If we look on the 3D here, we can see this mass is higher in and not in the chest but actually in the neck region, not even in a superior mediastinum.

We turn on color doppler and it's a hypervascular lesion or go associated with thyroid disease in the mother.

Here's a more epigenic mass, clearly intracardiac not in the region of the mediastinum.

This is a cardio rhabdo myoma situated in the right ventricle.

Mild Renal Pelvis Ectasia

Let's move on to renal psis.

And I think again this is another feature where the issue of size becomes critical.

Renal ectasis can be seen in a significant number of normal second trimester scans.

It's been estimated at approximately two to 3% as compared to 17 to 25% of trisomy 21 cases.

Most often renal psis is a normal variant, more common in males than females and particularly of no real significance if there's not associated ectasis in our practice we use a right pelvic diameter greater than four millimeters in the second trimester or greater than seven millimeters in the third trimester as our cutoffs.

We measured the AP diameter usually on a transverse view.

Here you can see this is a second trimester case where the pelvis measured five millimeters on the other side.

It was not measurable.

We always turn to do longitudinal views to compare the appearance of the kidneys to look for normal intrarenal anatomy.

This was a patient with gastroschesis.

You can see some dilated intraabdominal bowel loops with asymmetric renal pelvis.

Basically normal of no clinical significance.

Mild renal pectus is often transient idiopathic and can change even during one scan or from scan to scan.

We know that it can be associated with fetal bladder filling reflux and various variants including maternal hydration.

Often the finding can be bilateral and symmetric and it's more likely to progress if it's unilateral and asymmetric.

Here's a patient who had, the fetus with the bladder full and changing over time.

And these are various measurements of the renal pelvis to show you the different numbers that we can get almost up to four and five millimeters here and then back to four and three millimeters here with changes depending on what is happening with the voiding situation in utero.

Our concern for myre paralysis is likely again due to the fact that it is a minor marker for trisomy 21 with a 1.6 times increased risk when seen early in pregnancy over the, a priority risk of a patient who again is greater than 35 years of age with concern for trisomy 21, 1 0.7% of fetuses with mild renal p elects will have aneuploidy compared to about a third as many or 0.46%.

If there is isolated renal PS, there can also be a recurrence risk with the subsequent pregnancy and other than trisomy 21, my rarely renal psis can be associated with other aneuploidy type situations.

Renal um, psis is something that can be managed usually before um, pregnancy and we don't really recommend amniocentesis and particularly is that there is no indication if it's an isolated finding, particularly after a thorough assessment of the patient's maternal and baseline risk.

Here's a patient with mild renal ectasis.

And notice that there are other findings with absence of a nasal bone heart abnormality.

This is a common AV canal or endocardial cushion defect and a short femur length.

Other markers which makes this patient at more increased risk for the possibility of trisomy 21.

And this would be a patient you would wanna do amniocentesis on.

So what do we look for when we trying to decide if this is true renal p electros or not?

What we generally do is make the measurement of the renal pelvis if we see any fullness and then we turn to dual uh, longitudinal view to evaluate for ectasis.

We monitor the bladder for change, we look for intrarenal anatomy, we assess the gender and then look for other findings.

Here's an example of isolated very mild renal py ectasis five to six millimeters.

And if you notice turning on the sagittal view, you can see the fullness of the renal pelvis but no distended infundibulum or caly.

And this patient went on to a normal outcome greater than four millimeters and less than seven millimeters.

80% of those renal pelvis will likely resolve in utero and only about 17% will uh, persist after birth.

And of those very few need a postnatal evaluation.

Renal P elect is much greater than seven millimeters, rarely resolved in utero and could possibly progress.

So when we think it is significant, we wanna follow those patients and again, even in those cases a significant percentage will resolve postnatally.

That leaves us with patients who have persistent dilatation after birth and those are the patients who have to go on to a more detailed workup, usually starting with an ultrasound examination as a neonate.

Here's an example of a patient with very mild renal ectasis.

Here you can see there's no distension of the calouses, normal intrarenal anatomy with medullary pyramids and this was in association with a congenital diaphragmatic hernia.

Here we can see the liver is situated in the chest, and there is mediastinal shift, with the heart pushed over.

So it was a case associated with multiple anomalies, again, a left congenital diaphragmatic hernia.

On this view we can see bowel, we can see that there are bone abnormalities, there's tail piece and there's a 3D image showing absence of one of the ribs.

Pitfalls in Assessing Mild Renal Pelvis Ectasia

What are the pitfalls in assessing my renal py LECs?

There are normal variants such as an extrarenal pelvis, a very mild UPJ obstruction, prominent hilar vessels, but rarely do obstruction cases present as my renal py lysis.

Here's an example of an extrarenal pelvis.

By definition the pelvis should be outside the confines of the renal parenchyma.

And here you can see the renal tissue here.

So this is an extrarenal pelvis that measures a little bit more than four compared to the contralateral side.

That's two again, in a troublemaker, that's a male fetus.

Here's a left mild renal PY TSIs compared to a much bigger renal pelvis.

That's a right congenital UPJ obstruction.

Notice when we turn on this case on the longitudinal view, you can see that there's fullness of the infundibulum and dilatation of the Ks.

Echogenic Bowel

We are gonna end this talk discussing, echogenic bowel.

And I think the real issue with this finding is, is bowel definitely bright or knot?

It's important to remember that meconium occurs the bowel as early as 16 to eight weeks of gestation.

What it is, is actually a mixture of secretions including amniotic fluid cells.

It is, probably the least common of all of the findings we'll talk about today.

Seeing being seen on less than 1% of second trimester cases, it can be seen in intrauterine growth restriction, infection, bleeding and so forth.

And echogenic bowel can have, a homogeneous appearance.

I think the transducer we're using is important and note that it can be a non-specific finding and also transient echogenic bowel can actually be graded as zero to three.

I think the grade zero and one which refer to less than the liver or greater than the liver, but clearly less than the bone are basically within normal limits.

And grades two and three, which were equal or greater than the bone are potentially abnormal but not definitely abnormal.

Here's a patient who presented with an abnormal triple screen and here we can see that the bowel is brightly echogenic and clearly equal to at least the osseous structures that you can see come into play on, various images that we see here.

Notice that this patient is, not growing appropriately, approximately two weeks delayed, with a number of the biometric uh, measurements that we see here.

And this is an example of significant intrauterine growth restriction with what we call grade one echogenic bowel.

Grade two echogenic bowel, is at least equal to bone.

And here we can see that again, we have the iliac crest here.

Here's our echogenic bowel there as an isolated finding.

What is the significance of that?

If there is no other finding and often it is minor, here's grade three, which means more echogenic than bone.

And here we can see that this is actually the region of the sigmoid colon.

We can see the bowel extending up and this is large bowel up to the area of the splenic fracture.

Here's bowel all the way down to the pelvis, in the region of the rectal sigmoid colon.

And here we can see again a view showing this very bright echogenic bowel that is grade three.

What do we look for when we feel like the bowel may be echogenic?

Well, one of the first things we wanna do is we wanna pay attention to the transducer that we are using because higher frequencies can falsely increase echogenicity, then we change to a lower frequency and check the bowel at least with the five megaherz transducer.

True echogenic bowel by definition is usually focal.

It's often in the lower abdomen and even when it's a finding that's isolated, you have an adverse outcome in about 6% of cases.

But when it's mixed with other findings, depending on the significance you can have in up to a 50% adverse outcome.

Again, the issue with echogenic bowel is trisomy 21, with one to 2% echogenic bowel cases with having trisomy 21 with a 6.7 times increased risk over a priority risk.

So it's important to check for a number of other markers.

Here's a patient with severe intrauterine growth restriction, three to four weeks delayed and you can see the bowel appears mildly echogenic.

This kid is under distress.

There's a lot of, meconium staining.

The kid was delivered early.

Here you can see a few dilated bowel loops.

And in these patients sometimes it's better to determine if early delivery would end up in a better outcome rather than waiting.

Here's a case of complete heart block with bowel is schema.

You, you can see how the, heart is beating in this image where the, heartbeat is not being transmitted normally from the atri ventricles and notice that there is ischemia of the bowel which can be echogenic.

And here we can see brightly echogenic bowel at even greater than the boney structures in some cases very echogenic kidneys.

And we know that this kid is anemic because we can see a very spiky, elevated peak systolic velocity in this, middle cerebral artery.

Pitfalls for Echogenic Bowel or Pseudo Echogenic Bowel and Meconium Peritonitis

Graft pitfalls for echogenic bowel or pseudo echogenic bowel and meconium peritonitis.

Here's an example of bowel evaluated with a 12 megahertz transducer with a five megahertz transducer.

Here's a view where we can see fluid in the rectum.

Notice that the colon does not appear particularly echogenic when we switch from the 12 megahertz to the five.

The bowel is clearly within the normal range.

This is a case of meconium peritonitis and here in this case we can see that the bowel is e along the walls, but normal sort of hypo genic or fluid field bowel loops but only echogenic along the walls.

But pay attention to the fact that they're plaque like echogenic areas lining the peritoneal cavity on the region of the left upper quadrant and adjacent to the liver.

This is meconium peritonitis due to in utero bowel rupture.

When you have meconium peritonitis, you can have Waldorf pseudocyst and often the walls of those pseudocysts can be brightly echogenic in addition to the plaque like echogenic areas on the surface of the liver that we see here.

This patient actually had two pseudocyst and you can have associated ascites.

This is a case of echogenic foci that are not echogenic bowel loops, but this is echogenic meconium that is freed from the bowel plaque, like on the surface of the liver associated with the finding of ascites that we can see on this clip.

Conclusion

So in conclusion, I'd like to emphasize the fact that high resolution ultrasound allows us to detect a lot of very subtle findings actually earlier than we've ever seen them before.

And these should not be considered anomalies, but really structural features and they include at least six entities, c, PC, ventricular, magaly, EICF, the thymus, my renal psis and echogenic bowel.

Because these are commonly encountered, the most important things for us is to determine when there is significance and when, the patient can be treated more conservatively and the parents are not worried with us over diagnosing or misdiagnosing some of these, soft signs that can be misinterpreted.

And I think that application of very specific criteria including, precise measurements will help us improve the prenatal diagnosis, a number of these structural features.

Thank you for your attention.