 I am here to present a comparative study of the role of CT and ultrasonography in blunt abdominal trauma. Ames and objectives to study various radiological findings associated with blunt abdominal trauma to analyze and compare the efficacy of ultrason and CT in the diagnosis of blunt abdominal trauma to compare the individual merits and demerits and their superiority in the diagnosis. In this prospective study, 30 cases of blunt abdominal trauma were evaluated by Ultrason and CT in the Department of Radiology, BGMC Amhadabad between January 2021 to May 2021. Patients with abnormal physical examinations and abdominal symptoms, macroscopic hematuria, progressive abdominal distension, abdominal tenderness were included in the study. All patients underwent both CT and Ultrason and the time gap between the two was tried to keep the minimum. Ultrason was performed using the Samsung Okavix machine and CT was performed using 128 slice Siemens Sumetum Definition machine. Imagine technique was plain CT followed by IV contrast, oral induction contrast was given as per patient needs. Images were acquired following contrast in arterial venous and delayed phases. Reconstruction of the images with 1.25 mm sections was done. Multiplenar reformation and 3D reconstruction were done when wherever necessary. 70 ml of IV contrast was given, pre-scanned delay of 22 seconds for arterial and 48 seconds for venous phase was given and 5 minute delay was given in case of renal injuries, mainly to evaluate pelvic-alysal system injuries. No routine sedation was done. All images were viewed in soft tissue as well as long window settings beside bone window. Observation and analysis, blunt trauma in this series as health care in the world was found to be affecting the relatively younger age group 20 to 40 years who occupy about 58% and much more common in the male population, liver and spleen trauma. A liver injury accounted for about 50% on USG and about 67% on CT and spleen accounted for about 7% and 17% on USG and CT respectively. CT had detected 5 cases of hepatic trauma that were missed on USG and most of them were grade 1 injuries. CT had detected 3 cases of spleenic trauma which were missed on USG. Of these 2 were grade 1 and 1 was grade 3 injury. This is AAST grading for liver injury and spleen injury. Grade 4 and grade 5 includes vascular injuries, renal and pancreatic trauma, renal injuries occupy about 17% on USG and about 20% on CT. Pancreatic injuries occupy about 3% on USG and 13% on CT. CT had detected 1 case of renal trauma missed by USG which is a grade 1 injury and CT had detected 3 cases of renal trauma missed on USG due to obscuration by bubble gas. These are the AAST grading for kidney as well as pancreatic injuries. Coming to bladder and bowel injuries. In this study CT detected 1 case of bladder injury which was missed on USG. The reason for this could be the partially filled bladder and also CT's historiography was done when there was a doubt on blind scan. CT detected 1 case of bubble injury missed on USG which was 3% among all the cases of blunt injury to the abdomen. Though accurate localization was not possible pneumo peritoneum was found to be highly specific for bubble injuries in the form of perforation. Coming to hemoperitoneum. In this study there were 25 cases of hemoperitoneum which were detected both on USG and CT which is 83% among all the cases of blunt injury to the abdomen. And there were 3 cases of retroperitone hemorrhage which were detected on USG and CT which is 10% among all cases of blunt injury to the abdomen. And there were 2 cases of peritoneum which were not detected on USG but were detected on CT and which accounts for about 7% of cases of blunt injury to the abdomen. CT also picks up spine fractures. It is particularly excellent in depicting pelvic fractures also. This is the sensitivity and specificity of USG as compared to CT. In USG performed poor in detecting bladder and bubble injuries and also in periter wall hematoma and also in spleen and pancreatic injuries. These are the positive predictive value and negative predictive value of USG. Discussion The challenge in imaging of abdominal trauma is to accurately identify injuries requiring early exploration and at the same time avoid unnecessary operative intervention in cases that can be managed conservatively. In recent years CT and USG have replaced all other modalities of investigation up to a greater action. Omission of oral contrast agent in suspected bubble injury cases was not to be of any significant disadvantage in this series as one bubble injury which was detected on CT was confirmed on surgical exploration. Results In this study hepatic trauma was the most common injury detected on both USG and CT and this is a variation from standard surgical description of more common splenic injuries. The reason might be that surgically occult liver lesions are picked up more with the use of abdominal CT. Renal and spleen injuries were also common and were the most common injuries detected after hepatic trauma on both USG and CT. Pancreatic and urinary bladder trauma were low in frequency in accordance with literature. Immoperative is quite high in incidents probably derived from multiple sources. Few cases of retroperitone injuries, abdominal and pelvic fractures were also detected mainly by CT. Compared with CT, USG has low sensitivity for pancreatic, bubble and bladder injuries. Compared with USG, CT is extremely accurate and valuable in predicting occult bubble injuries in the form of traumatic perforations even without the use of contrast opacification of bubble. USG along with CT has a very vital role in accurate diagnosis, source localization, quantification, management decision making in hemoperitoneum. CT is excellent in diagnosis of associated injuries of spine, pelvis, skeleton and hence it is a single setting complete examination technique for a trauma patient. Conclusion CT is a superior diagnostic modality in the diagnosis of abdominal trauma. USG can be valuable in investigation, however USG can miss crucial injuries and may lead to inappropriate management in some patients. Hence it is imperative that all USG positive cases should be followed by CT. Similarly, CT must also be performed in symptomatic patients with negative USG scans and in patients with suboptimal USG scans. Although a higher USG or CT scoring of hemoperitoneum increases the chances of surgical management, hemodynamic instability and accurate imaging diagnosis or the main determinants which dictate the type of management strategy. It appears that asymptomatic patients with normal clinical examination and ultrason scans can be followed up without CT scan or indoor admission, restricting CT for only USG positives and USG negative symptomatic patients and for unsatisfactory USG examinations. These are the references I took for my study, thank you.