Computer generated transcript

Warning!
The following transcript was generated automatically from the content and has not been checked or corrected manually.

Hi, everybody. Um, my name is Yo and I am a junior clinical fellow in Neonatology here, London. Um, I thought it would be a good idea to spend the next 20 odd minutes discussing cranial ultrasound scans in, in the NICU. Um, it's perhaps one of the most important and commonly performed procedures and investigations in in newborns, especially in the neonatal intensive care unit. And, um, I thought it would be a good idea to, to talk about that. Today, it's gonna be the first of the series. Um And today it's just gonna be about the importance and the, the, the common images we require in a different session. We will be talking about pathologies and advanced um imaging in, in, in the neck. So in terms of the benefits of green ultrasound scans, it's, it's one of the safest in terms of the fact that it does not use um, ionizing radiations like x rays and CT scans. It's also relatively quick, you know, you can perform it at the bedside. And when you think about the logistics of moving an intubated baby down to the MRI suite for a scan, the ultrasound scan is a much better alternative. In that sense, it's also quite reliable and inexpensive and you can use it to image early, you know, assess the timing of an injury and you can use it to monitor the evolution of the brain lesion as well as monitor development your neurodevelopment and in pretense for instance, and you don't need to sedate the baby, although you don't need a settled baby, but you don't actually have to sedate the baby for, for the study. Um Cranial ultrasound scans uh in most units, they're done routinely, you know, for every baby admitted, we work, they all get an ultrasound scan and preoperatively postoperatively and at routine time intervals, day three, day, seven, day 1410, they are done to assess development of the brain as well as many possible lesions that might have been identified earlier. Um But in terms of prematurity, it's, it's used to assess for I VH as interventricular hemorrhage, ventricular dilatation, cystic ravenia in babies with seizures or encephalopathy from hypoxia. For instance, it's quite useful um in infection by either congenital or postnatal infections like CMV to of osmosis. You're looking out for periventricular calcifications, lenticulostriate vasculopathy and things like that. Again, we will discuss the pathologies in a different media um in babies who have suddenly deteriorated. Um those hemoglobins have dropped, for instance, pre ultrasound scans can identify bleed in the brain and and any possible causes of of, of such such deterioration in babies with microcephaly microcephaly, um obvious dysmorphic features or the associated congenital abnormalities. You could use the clean ultrasound scan as as a screening tool or a diagnostic tool to rule out brain lesions or the midline lesions. For instance, um commonly used in prognostication and and deciding the direction of care in in in pre 10 new ones. For instance, with extensive PV, you know, who would probably not benefit from continuing intensive care. Of course, the parents have to be carried along in such decision making process. But having the cr scan and ultrasound scan images of the brain does definitely help in making such decisions. In terms of the technical aspects of ultrasonography, we tend to use the the transducer probes with the 5 to 10 megahertz frequents for cranial ultrasound and most standard exams use between 7.5 and eight megahertz um in babies who are much bigger, who have big hair and to image deeper structures, you tend to use lower frequencies in your five megahertz range and in smaller babies or for more superficial structures, you tend to use a 10 megahertz or higher frequency probes. And of course, you have to use a proper size probes cause babies can be range in sizes from really tiny 600 g, three times to larger babies. Um and most probes like the one I have on the right here, I have markers on the side, usually on the right that show they can orient the probe with the baby. So the marker should be on the right side of, of the baby. In my unit, we tend to use the C 310 probe which the three and 10 corresponds to 3 to 10 mega frequency. This is from general electric. I think in terms of the windows that we tend to use for the scans. Um for most standard scans, we tend to use the anterior frontal and most people will just stop at that. And that is usually quite sufficient for, for most scans. But to have a better look at the cerebellum or the posterior fossa. For instance, sometimes they have to use the mastoid fontanel or the posterior fontanel and sometimes the, the bregma as well. But most commonly, the the anterior fel will suffice for most most investigations, we tend to take images from the Coronal view and the sagittal view. Um And for a good study, you probably need about 12 images in total six from the Coronal view and five images from the Sagittal and parasagittal views. Again, it could take supplementary views from the mastoid and the posterior front. And in addition, sometimes we take um we do what we call a dopa study to measure the resistive index, the ri in cases such as like HIV, right. So we take again, six images in the Coronal view, C one to C six and we'll be looking at the different images in a few moments. So the first um slice is the C one. And as we can see to the right is the, it goes through the frontal lobes, right, the most anterior slice. And it has the advantage of helping us standardize our study or orienting our probes and ensuring symmetry whilst taking the scans. So we can see the inter fure the fox that everybody goes through that. And the first thing we want to do is ensure that the right side of the probe corresponds to the right side of the baby. And we can see a marker here that helps with that. So this is the right hemisphere and the left hemisphere, the fissure has to be in the midline in the middle that helps to avoid any kind of asymmetry during the scan. Again, we have the frontal lobes on the right, the left, we have the supraorbital bridges and we have the orbits. We can also see things like cysts or um cystic pedia, sometimes intracom hemorrhages. And we can assess for extra XL spaces why an extra XL space in in this slice. The second slide goes through the anterior on the cavum septum piceid. And we can again see the entire hemispheric fissure, the frontal lobes. Here we have the carpus callosum um and the the frontal end of the lateral as well as the cavum septum callosum, which in most babies happens to be a normal variant, although it can become abnormally large in um certain genetic conditions we also have the con fissure here and the temporal lobes as well. Here, we'll find the card nucleus, the end of the cardiac nucleus and more inferior area of the pre. And the glu was probably this um this slice, this this the third coronal um slice goes through the the third ventricle. And that's the most important landmark on the slice. So again, we have the inter fissure part of the frontal lobe, the body of the lateral ventricles. Um again, the cum septum pilum and the third ventricle, which kind of highlights that this is C three. Um It is in this view that we usually tend to access ventriculomegaly. So in most babies, we expect the ventricles to be almost sleep like. And if pain l we can then measure what we called ventricular index on the slide. Again, we will discuss this in further sessions. Again, we have the se in future, we have the temporal lobes and here we have some bits of the the brain stem as well. The C four goes through the cerebellum, the body of the lateral ventricles. And we can assess the the brain stem and the cerebellum. In this view here, we have the deformis of the cerebellum, the cerebellar lobes, the C magna, we have the tertium and we have the temporal lobe here as well. Again, infusion helps to sort of avoid asymmetry when a images we can still see bits of the, the lateral ventricle and the cava septum pid. On this view, the C five view goes through the trigone of the lateral ventricle. Here, we have what I like to call the banana shaped and choroid plexus becomes obvious here. And we have, we can assess the ventricle size. We also have in some cases the, the septum validum in this case. And we have the periventricular brush um which is just white matter around the, the, the ventricle, the lateral ventricle. It can, we can sometimes assess the cerebellum and then the pa polyps. Here in C five, the CC is the most posterior slice going through the peral lobes on the occipital lobes. And here we can send for cystic changes per and again, we can use this to standardize our, our slice. The other important thing is the sagittal and parasagittal views. Here we take a slide through the midline and two parasagittal views on the left and on the right, the midline view um again, goes through the midline. Um Here we have most importantly, the copper color from a good midline. She'll highlight the copper color in full view. So she'll see the, the rostrum, the genu, the body and the splenium of the corpus callosum as well as the front of the corpus callosum. And then you can also see the cavum velum septum Callum in, in, in the midline, you can see the singular gyrus above the corpus callosum and you can see the third ventricle this is the thalamus, this is the aqueduct of Sylvius leading into the fourth ventricle and you have ac magna inferior to the cerebellum. The phonix detect and the cerebellum give give rise to what we call the Victorian lady silhouette. And if you can see this, you know, that you have a really good midline view and this helps to, you know, standardize your view. Again, in this view, the, the Mao approach should point towards the nose of the baby. And that sort of helps to standardize your image. The first part I told you s two or S four right on the left, on the right and you determine which way you wanna go first. Um It is a good view to look at the card, the card view. So here we have the head of the cardio and here you have the thalamus and the groove in between is called the CTN, the cardic notch and the groove. And that is where we tend to see geminal matrix MHS. So this view is particularly important for assessing for GMH matric hemorrhoid. You can also assess for the, the ventricular size and look for ch plexus abnormalities and chx or cysts um um posterior to the ventricle. You can assess for cystic p in the para occipital lobes as well as assess for the cerebellum as well. But most importantly, here in this view is assessing for CTN cysts or um seminal matrix hemorrhages in this group. In the most extreme S3 or S five images. The most important thing is to have a look at the fissure. That's what determines um the extreme cross over you. So you have a fissure here, you have the insulin above. And in this view, we can assess fully for any cystic perent hemorrhage or periventricular maasia in this, in this view, as well as any um in fact, or hemorrhages as well in the midline view, like I mentioned earlier, sometimes we measure what we call the resistive index and this helps to assess for encephalopathy resulting from hypoxia or other causes. Um We tend to use the anterior cerebral arch for the most. And what we tend to do is place a marker on the peak systolic velocity and place a marker on the the lowest diastolic velocity. And it comes up with the resistive index automatically after measuring um we use the pulse wave and the color and it's um in in subsequent sessions, I will discuss how we we acquire such images on the right. It's just showing the formula that we use, basically subtracting the diastolic velocity from systolic velocity and to by the systolic velocity. And that gives us the resistive index. It can be abnormal if it's too high or if it's too low. And again, we will discuss that in and subsequent sessions. These are my references and I hope to see you in in the next session. Thank you.