 Hello everybody, I am Dr. Avneesh Kandil, Lead Consultant Radiologist at ASTEMM Scottical. I am also a faculty member of Indian Radiologist and I am very passionate about teaching and making things a bit more simpler. So in this current video I am going to be talking about Sonological Assessment of the Endometrium and the points that we need to be considering when we are evaluating the endometrium and how exactly do we approach it. So I hope this is useful for you. Thank you. This is Sonological Assessment of the Endometrium. Endometrium has a wide spectrum of appearance, it is a very dynamic structure and it is pretty variable during the various phases of the menstrual cycle and there is a lot of variations seen in the various age groups also. So knowing the difference in the different age groups and the difference in the appearance during the various phases of the menstrual cycle is important for us to know which is normal and identify which is abnormal. The optimal modality of choice for imaging the endometrium is a transvaginal scan. So when we are evaluating the endometrium like I mentioned before, there is a variation in the different age groups. So we have to know what is normal and what is not normal for the different age groups. During the neonatal period there is, there can be minimal residual hormonal influence because of which the endometrium may appear to be prominent or thickened though we expect it to be thin in the premenstrual phase or the premenarcal phase but still in neonates it can be prominent because of residual maternal hormonal influence. But further from this in any of the years prior to the pre-puberter age the hormonal influence from the maternal hormones has regressed and so we see an endometrium which is thin and uniform that's what the normal appearance will be. Then in the reproductive age group there is a lot of variation based on which phase of the menstrual cycle that the patient is in. So we will be dealing with it in detail further on. Then comes the postmenstrual or the postmenopausal age group during this period the estrogen hormone influence has regressed and so there is an atrophy of the functional layer. This leaves behind just the basal layer which is a thin and uniform layer and we expect it to be thin and uniform and anywhere less than 5 millimeters. This is accounting for the fact that the patient might be on a hormone replacement therapy also even then we expect that the endometrial canal or the endometrial thickness should be uniform and thin and measures less than 5 millimeters. So what is it that we are assessing in the endometrium? We look at the thickness of the endometrium. We correlate this thickness with the age of the patient that we mentioned the different age groups and the appearances during the different age groups. We correlate it with which phase of the menstrual cycle that the patient is in. Further from the thickness we look at the echogenicity of the endometrium. We look at the homogeneity of the endometrial texture if it is homogeneous or heterogeneous if we are seeing any focal echogenic or focal hypoechoic structures within. We look at the contour of the endometrium we look for any bulges in the endometrium or we look for any indentations or in growth center of the endometrium. We also have to look for any vascularity in areas of increased vascularity or any focal area of altered echotexture with any change in the vascularity. We have to assess all of these things when we look at the endometrium. So how do we measure the endometrium? The ideal technique would be to employ a transveginal scan but for the patients in whom we cannot do a transveginal scan we can go ahead with a transabdominal scan. Either ways the measurement of the endometrium is done in a metcichietal plane in the long axis and during this the entire endometrial lining needs to be visualized right up to the endocervical canal and we have to measure the thickest echogenic area of the endometrium for getting the right endometrial thickness. This means that from one basal interface to the other basal interface or from one echogenic end of the endometrium to the other echogenic end at the widest part is the endometrial thickness. So what are the things that we have to bear in mind when we do this? The part beyond the echogenic end of the endometrium or the basic layer of the endometrium is the hypoechoic myometrium or the inner myometrium or the junctional zone and this should not be included when we measure the endometrium. Very often we do see minimal fluid within the endometrial canal and when we are measuring the endometrial thickness this endometrial fluid should not be accounted for in the measurement. So what are the layers of the endometrium? On the left side of the screen we can see a transfer channel scan of the uterus which is showing us a trilaminar appearance of the endometrium and the outer echogenic area of the endometrium is the basal layer. The lining within it the hypoechoic area within this echogenic area is the functional layer and the central echogenic line that we are seeing is the endometrial canal. Now the thin hypoechoic area that we are seeing beyond the basal layer is the inner myometrium, the hypoechoic myometrium, inner myometrium or the junctional zone and we specifically make a note of this when we are looking for the adenomyces. So what are the layers of endometrium? The layers of the endometrium are the basal layer and the functional layer. The basal layer is the one which is adherent to the myometrium. It is the supporting layer and which helps it regenerate. The inner layer is the functional layer. It overlies the basal layer. This is the layer which responds to the hormonal stimulation. So this is the layer which undergoes changes during the various phases of the menstrual cycle. This is the layer which prepares for the implantation and the one which gets shredded during the menstrual phase. So what are the phases? We said there's a change in the endometrial lining during the various phases of the menstrual cycle. So what are the various phases? There's the menstrual phase which is the beginning of the cycle. Then we have the proliferative phase which has the early and the late proliferative phase and the secretory phase. So let's look at the different appearances during the various phases. The menstrual cycle which is beginning with menstrual phase, it lasts from the first of the fifth day and during this time the functional layer has shed. The endometrium is the thinnest during this menstrual phase and it appears like an echogenic thin line measuring from 1 to 4 millimeters. Then we have the early proliferative phase which lasts from 6 to 14 days. During this period there is an increase in the hormonal influence. As a result of which there's a proliferation of the basal layer. There's development of blood vessels and glandular tissue and so the endometrium appears more echogenic than it was in during the menstrual phase and it measures from between 5 to 7 millimeters. Then we have the late proliferative phase or the peri ovulatory phase which lasts from 15 to 17 days. During this phase we have the glands, the blood vessels and stroma increasing. There is a twilight appearance of the endometrium and it can measure up to 11 millimeters. Last part of the cycle is the secretory phase which is lasting from 18 to 28 days during a normal cycle. During this part the functional layer is the most edematous. There's stromal edema, there's a lot of mucus, a lot of glycogen because of all this the endometrium is very edematous so it appears thick and echogenic and has posterior acoustic enhancement and the thickness of the endometrium during this phase can go up to 16 millimeters. The thing that we have to bear in mind during this with all of this is that none of these numbers are hard and fast rules. You can have a thickness which might go beyond these set limits and yet be normal. So if the patient is asymptomatic we can follow up the patient in the next cycle to assert that it was just a change in the numbers. It can very well be a normal endometrium and still waver from the normal thickness that has been mentioned. So what are the various tips that we need to bear in mind other than what we have already mentioned? When we look at the endometrium I mentioned we measure the thickness of the endometrium in the mid-segital plane but that is not the only way to look at the endometrium that is the plane in which we measure the thickness of the endometrium but we have to look at the endometrium in its entirety. So the endometrium needs to be seen in the longitudinal and the transverse plane and from one corner to the other corner to ensure that there is no focal elation, no focal irregularity in the endometrium in any part of the endometrium along its entire length. Further from this we have to look at the endometrial texture. We have to be sure there is no focal lesion, echogenic or hypoechoic and because an endometrial carcinoma, polyps they all can present as they all normally present as focal lesions. When we have fluid within the canal I mentioned earlier also we should not measure it when we look at the endometrial thickness. So what do we do other than that? We have to measure each layer of the endometrium separately and then add it like supposing look at the picture on the right hand side of the screen. We see that there is minimal fluid in the canal so you look at the endometrial measurement of the anterior lining and the posterior lining and add on both of these supposing it is 2 millimeters and 2 millimeters the endometrial thickness becomes 4 millimeters. Many a times due to various reasons like presence of fibroids, obesity of the patient, position of the uterus we may not be able to look at the endometrium properly. If this happens we should mention that the endometrium is poorly seen because we saying giving a measurement of the endometrium and mentioning that it is normal might pass that patient off as a normal patient but that patient might be having a subtle abnormality or a subtle endometrial malignancy or a polyp which might go unseen. So what do we do for these patients in which we are not able to see the endometrium properly? The next thing that we look for in these patients is a sonosalpingogram which is instilling fluid into the endometrial canal which helps us delineate the endometrial cavity and the endometrial lining beautifully and very subtle lesions can also be delineated beautifully with a sonosalpingogram so for all the patients on whom we are not able to look at the endometrial lining well a sonosalpingogram is recommended and another thing that we need to bear in mind is long-term usage of OCP can cause thinning of endometrium so when we see the various things our appearance or the thickness of the endometrium we have to make sure we are keeping in mind the age the phase and the probability that the patient is under God is using is having some other medications which might be influencing the endometrial thickness so with this we understand that endometrium is influenced by a lot of factors and knowing these factors will help us determine whether the endometrium is normal and the ways that the endometrium is looked for is not just the thickness but also the ecotexture the ecogenicity ecotexture the contour the bulge indentation vascularity of the endometrium so always look at the entire picture and don't just stop with what you see so there's a lot of things that comes further in the endometrial pathology which will be taken up one by one as it comes