 Greetings, everybody. My name is Dr. Vivek Darga. I'm a junior resident at Justice K. S. Agra Medical Academy at Mangalore. Today, we are going to discuss about MDCT evaluation of acute non-traumatic vascular mesentry pathologies. Mesentry pathologies, especially mesentry ischemia, are increasing in incidents as the population ages. High morbidity and mortality rates are largely related to delayed diagnosis of these conditions. Conventional angiography has always been considered to be the gold standard for the diagnosis of ischemia, which is an invasive procedure. Whereas MDCT is now regarded as the first line imaging modality to confirm the clinical diagnosis or suggest an alternative condition, which may explain the patient's symptoms. The aims and objectives of our study was to present the characteristic multi-detector computed tomography, that is, MDCT features of non-traumatic acute vascular mesentry pathologies. Ours was a retrospective study of 15 patients, which included nine men and six women, who had underwent CECT study between January 2020 to September 2022. These CECT examinations were conducted with GE128 slice CT scanners at the Department of Radiology of Justice K. Sagrange Irritable Hospital at Mangalore. Images obtained during the RTL and the venous phases were analyzed for the presence of findings involving the mesentry in patients who presented with acute abdominal pain. And who had no history of trauma. Moving on to the results of our study, the age distribution ranged between 26 and 73 years with male predominance. The male is to female ratio for our study was 3 to 2. The causes of acute mesentry pathologies that we have covered included mesentry ischemia. So out of these 15 patients, seven cases were of mesentry ischemia, seven cases of omenital infarction, and one case of epiploic appendicitis. The demographic data of patients who presented with mesentry ischemia, sort of those seven patients, six were males, one was a female. Out of these seven patients who were diagnosed with mesentry ischemia eventually, five of these patients presented with acute abdominal pain. One patient had a history of infective endocarditis while one patient was a known case of pancreatic carcinoma. The findings in patients with mesentry ischemia, the most common finding that we found was hypo enhancement of small intestinal walls, small intestinal loops followed by peaches of small intestinal obstruction, pneumatosis intestinalis, and the presence of SMA thrombosis. While mild asitis was seen in two patients, which was the least common finding in our study. So here we can see axial and acetyl image, arterial phase, amyp image, which shows the presence of a thrombus in the superior mesentry cartilage. So here we can see there is absence of contrast filling, which suggests presence of thrombus. This is an axial image which shows the bobble loops being very thinned out, which is what we call as paper thin small bobble loops. So because of ischemia, the bobble walls will become very paper thin. Some of the patients also presented with features of small bobble loops. Here we can see there are multiple dilated small bobble loops with air fluid levels and prominent valvular conventus. Here we can see air density is noted within the wall of the small bobble, which is called as pneumatosis intestinalis. And the pneumatosis intestinalis was quite severe in one case, which also extended to involve the portal vein and its branches. So here we can see the axial image and the coronal image showing the presence of air within the portal vein radicals. The second condition that we considered was omental infarction. So we had seven cases out of which four were males, three were females. So these cases were clinically presented as right lower abdominal pain, who were clinically diagnosed as acute appendicitis in four instances. While these patients presented with right upper abdominal pain and clinically they were suspected to have acute cholecystitis in two cases. Whereas one patient was a female who presented with left lower abdominal pain. She had a history of hemorrhage exist in the left ovary in the previous scans. So based on that, this presentation was clinically suspected to be a rupture of that hemorrhage left ovarian cyst. So we performed in the city of these patients and the clinical finding that we found in all of these cases was, so there was involvement of the greater omentum. The lesion or the fat density, fat standing that we saw was about round to oval in shape. It was a fat density lesion with fat standing. And we could not define any continuous or any peripheral margin for this lesion. Etiology of omental infarct, primary infarct as we'll discuss ahead. So in these cases, we could not find the cause of this infarct. So hence the name primary infarct was about five cases. And secondary infarct, so these patients who had secondary infarct, they had a history of inguinal hernia previously. So that was the cause of omental infarct because of the torsion in these cases. Moving on to MD60 features of omental infarction. So something assigned that is typically described as world sign. So it appears as streaks due to the whirling of omentum on its vessels in a concentrated pattern. Usually these lesions measures more than five centimeters are about triangle, oval or round in shape. They are heterogeneous, fat density lesion and they do not have any enhancing room. Usually these are not associated with any bobble ball technique. However, if the omental infarct is close to any adjacent bobble loop, so a reactive wall technique in those particular loops can be seen. So this is what is defined as the world sign. So the arrow that you see here, so this was about hazy omentum with concentric hyperdensity and whirling pattern. As you can see, it's like a cyclone as it whirls around. In the right iliac fossa and which is abutting the cecum posteriorly as marked in the image. This was another case which showed a fat density lesion with hyperattinuating streak infiltration between the abdominal wall anteriorly and the transverse column posteriorly. So this was a case of omental infarct in the right iliac fossa. So the patient presented with RIF twin and clinically what was suspected from the surgery department was likely acute appendicitis. However, this was the CCT finding. This was another case which demonstrated actual and coronal contrast images showing oval fat density lesions. Again, we can see that bobble sign and streaky appearance with the broad base towards the parietal peritonium. The region was noted here again between the ascending column and the anterior abdominal wall. Another image, again, here, we do not see the classic wall sign. However, we can see very hazy and a streaky appearance of fat density mass in the right iliac fossa, which is again abutting the parietal peritonium. And this was one case which was a case of secondary omental infarction. So this was area of fat density, as you can see this curved arrow herniating into the right inguinal region. So the patient already had right inguinal hernia and the omentum was content of it. So because of the omentum twisting, the omentum, regional omentum underwent infarction, which gave rise to patients symptoms. The third entity that was epiploic appendicitis, we encountered one case that one case was a female. So this, again, a patient presented with left lower quadrant pain and she was suspected to have ruptured hemorrhagic ovaliancyst again based on a previous ultrasound report. So it was just clinical suspicion. So the finding that we found in this particular patient with epiploic appendicitis was a paracolonic void fatty mass. It was well-defined hyper-retinuating rim around the mass. So unlike omentum infarction, here we could make out a very well-defined hyper-retinuating rim and occasionally a central high attenuation was found. So the reason for all of these findings was why do we see it as an ovoid fatimus because epiploic appendicitis, they are usually tubular fatty structures. A well-defined hyper-retinuting rim was found because it represents the inflamed peritoneal lining surrounding it. And why do we find a central high attenuation areas? The reason for that being the thrombose vessels in the center and because of the hemorrhage, the area appears hyper-dense. So this was that image which showed a very well-defined rim enhancement here and central high density because of the hemorrhage. And this peripherally enhancing rim represents peritoneal inflammation. So this was a case of epiploic appendicitis in the left ilac fossa, but clinically the patient was suspected to be having a ruptured hemorrhagic system. Moving on to the discussion part. So mesentric ischemia occurs when there is compromised blood flow to the small intestine. It is typically classified into two types, acute mesentric ischemia and chronic mesentric ischemia. We'll be dealing only with acute mesentric ischemia. So in acute mesentric ischemia, as we move ahead, the causes can be because of either occlusion to the arteries or vessels or it could be non-occlusive. So when we talk about occlusive, it could be either occlusion to the arterial supply or occlusion to the venous supply. So again, in arterial supply, a thrombus would be forming or eventually it may embolize. Whereas in venous, the occlusion would be definitely because of thrombosis. So acute mesentric ischemia is one of the most serious and life-threatening abdominal conditions with an estimated mortality ranging up to as high as 80%. Amboli to the SMA, supidine mesentric artery, are typically associated with cardiac arrhythmia such as atrial fibrillation. Now why is SMA very prone to be getting involved in it? Because SMA has a white caliber lumen and it has a narrow angle takeoff as it originates from the abdominal aorta below the celiac axis. And hence, these conditions make the supidine mesentric artery more susceptible to these amboli. So if you have a large embolus, it will most often lodge in the proximal part of SMA because a larger embolus will not be able to go beyond it. And hence, it will result in extensive involvement. Whereas smaller emboli will lodge further more distally and may affect only small segments of bobble and owing to availability of collateral flow, the rest of the bobble loop may be saved or may not be involved. Just like we mentioned about occlusion of the arteries. So ischemia can also occur because of thrombosis of the mesentric veins. However, it's a very lesser common cause of mesentric ischemia. So patients particularly with hypercoagulable states or who have polycythemia or patients who are taking oral contraceptives are susceptible in presenting with thrombosis of mesentric veins leading to ischemia. These were the causes of, these were the occlusive causes of mesentric ischemia. However, there could be some causes like non-occlusive causes. So these occur when there is a decrease in the blood pressure typically associated with either cardiac failure, trauma, widespread sepsis leading to septic shock or certain drugs like cocaine which result in splanknic vasoconstriction to preserve blood flow to the heart and the brain. So in these conditions, what is happening? As such, there is no occlusion in the vessels supplying it, but because of the decreased blood pressure, the condition may arise that is mesentric ischemia. So embolied with the supidermesentric artery accounts for approximately 50% of the cases. As we mentioned, the white calibre lumen and an arrow angle takeoff from the abdominal aorta. These are the conditions that usually will tend to involve the SMM more than the other arteries. The second condition is omenital infarction that we discussed. So the created omentum is a large paternal fold and is continuous with the visceral peritorium of the stomach and the transverse column. It contains fat and blood vessels. Most commonly, infarction occurs on the right side and it is likely due to a long and mobile omentum. However, this need not be necessary. Omentum, as we know, it covers the entire abdomen and hence, omental infarction can take place anywhere. This omental infarction works classified by Lettna at all in 1952 and it has been cited in many studies. So the classification that they give is into primary and the secondary. So secondary omental infarction is caused due to torsion of omental vessels caused by a decision between the omentum and any pathological foca. So in our case, the pathological foca was vernia. It could also involve surgical scar or any tumor. So because of these conditions, the regional omentum may undergo torsion and hence may undergo infarction. Whereas primary omental infarction is called when we could not identify any cause. The third condition was epiploic appendicitis. So again, this is a very close differential diagnosis on CT for omental infarction. So appendices epiploic are pedunculated fatty structures which arise from the serosal surfaces of the colon. So what basically is the pathophysiology of epiploic appendicitis is these are pedunculated, shaped and they're quite mobile. So sometimes they can undergo spontaneous torsion as a result of which they could either undergo ischemia or hemorrhagic infarction, which will lead to local inflammatory process and hence later on inflammation leading to epiploic appendicitis. So what happens is when they undergo torsion and when they bleed, so it will have a central hypertensive region and the peripheral rim that we discussed is because of the peritonal inflammation. These are the three conditions. So the take home message from today's paper presentation is that MDCT depicts misintric ischemia and its underlying causes also its severity. Knowledge of imaging findings of various misintric pathologists can guide further life-saving interventions in serious conditions like acute misintric ischemia. At the same time, it can also avoid unnecessary surgical interventions in self-limiting diseases like appendicitis and omental infarction. So all these cases of omental infarction and appendicitis in our institute were treated conservatively for two to three weeks and all of these patients had basically no symptoms after that treatment period and hence unnecessary surgical intervention including laparoscopy or laparotomy was prevented in all these cases because of the diagnosis based on MDCT features. Omental infarction should be considered important in the differential diagnosis of acute abdominal pain which can mimic acute appendicitis. These were the references for my discussion. My name is Dr. Vivek Ramesh Nelda. Thank you. Thank you very much.