 Hello friends and welcome to Indian Radiologist.com. In this week's video we are going to focus on an interesting case of a 47 year old female with a history of hysterectomy in the past who presented to us with severe lower abdominal pain and bleeding PV. A USG abdomen and pelvis was asked for by the casualty officer. The abdominal sonography of this patient was normal and an internal sonography was then performed which shows a normal cervix as you can see on this video. But just adjacent to the cervix towards the right of the cervix we can see a small nodular structure which is solid and eco-poor. On closer examination and zooming that area we can see it's quite irregular and appears to be adherent to the cervix and not separate from it. As we push further we can also see that it is attached to the rectal wall. On Doppler it showed moderate vascularity with a history of being operated for endometriosis. The diagnosis in this case becomes quite simple. It is nothing but deep infiltrating endometriosis or DIE. We all know that endometriosis is defined as the presence of functional endometrial glands and stroma outside the uterine cavity. And deep pelvic endometriosis as we know it commonly as deep infiltrating endometriosis is defined as subperitonal invasion by endometriotic lesions that exceed 5mm in depth. Deep pelvic endometriosis can affect the retro cervical region commonly but also the uterosecral ligaments, the rectum, the recto vaginal septum, the vagina, the urinary tract and other extraperitonal pelvic sites. Clinically like with endometriosis it is commonly associated with dysmenorrhea, dysperunia, pelvic pain and urinary tract symptoms. But it is a very important cause of infertility and that's the reason why patients usually come to us for examination. The case that we saw today was just an unusual way of presentation with acute pain and severe bleeding but commonly the patient will come to you in your ultrasound clinic for workup for infertility. The idea group has given a four step method in evaluating endometriotic lesions as well as DIE. The first step of course is the routine evaluation of the uterus and adnexa as well as the sonographic signs of adenomyosis and or presence or absence of endometrial cysts which is very commonly seen. During the scan it is not a bad idea to actually evaluate the kidneys as well to look for any hydroneftrosis or hydrourita that might occur due to an endometriotic lesion which may not be seen in the ureter on a transvaginal scan. The second step is evaluation of the transvaginal sonographic soft markers such as site specific tenderness and ovarian mobility. The third is evaluating the status of the pouch of Douglas using the sliding sign and lastly assessing DIE nodules in both the anterior and the posterior compartment. So as we see here the anterior compartment will consist of lesions that exist at the bladder base or the bladder dome. So we need to evaluate these areas well. The posterior compartment will include the rectovaginal septum and also nodules that cradle the posterior vaginal phonics the edge of the cervix as well as the rectum as was seen in our case and eventually also the utrosacral ligament posteriorly as well as the rectum and the rectosigmoid. Now as we do scans normally we see these lesions pretty commonly these endometriotic cysts that we label and measure and compare with previous scans but while doing the transvaginal scan we need to learn a few tricks that will allow us to evaluate these patients well. The first is adequate bowel preparation. We all know that the patients usually walk in directly for a transvaginal scan and there's no preparation required but when we start scanning and we get this picture with fecal shadow noted within the bowel on the left side that totally obscures the left adenis and the ovary you know that your examination is going to be suboptimal. So in this case rather than completing a suboptimal examination it is not a bad idea to call the patient next day with adequate bowel preparation. So you should see to it that the rectum and the rectosigmoid are usually collapsed and flat and you can see the wall pretty clearly. The next step is gel sonovaginography. Now what is this? This is actually a wonderful article that you all must read written by Dr. Mala Sibyl in which she outlines details of how she packs the vagina with copious amounts of gel at least 10 to 20 cc that allows a much better visualization of the posterior phonics as well as the cervix that would otherwise escape adequate optimal visualization on a regular ultrasound. The third tip of course is a sliding sign to CPOD lesions as we can see in this case we are seeing the left ovary and as we push the probe inwards gently and push it back you can see the ovary separating from the rectal wall. In this way you can note and tell very clearly whether the ovary is adherent to the rectal wall. In this technique we see whether the anterior rectum is gliding freely over the posterior aspect of the uterus and the cervix. A normal sliding motion of the uterus is regarded as a positive sliding sign and this is very important to diagnose POD lesions as well as adhesions at the pouch of Douglas between the uterus and the rectal wall. By doing this we also evaluate the rectal wall well and we look for rectal nodules that you would otherwise miss while conducting a scan without performing the sliding sign. So doing the sliding sign is a must usually when evaluating for endometriosis. We do know the limitations of TBS ultrasound of course it has a restricted field of view and it may be difficult to visualize lesions located outside the pelvis especially recto sigmoid lesions. Other common conditions that might impair lesion visualization are large ovarian cysts, sub-serosine leomaumas and of course acute retroflection of the uterus. Sometimes the uterus might be retroverted and totally adherent to the rectum and this might not allow you to see rectal nodules that you would otherwise see in a slightly mobile uterus. However ultrasound is still the first initial investigation of choice in patients in whom endometriosis is suspected and a complete detailed evaluation of the pelvic structures must be performed in order to diagnose endometriosis accurately. In most cases especially those who will be going for surgery MR of the pelvis is conducted to confirm these nodules as well as to see lesions that might escape detection on transvaginal ultrasounds especially lesions that are higher up and involving the recto sigmoid.