Role of USG and Contrast Enhanced Computed Tomography in Diagnosis of the Local Complications of Acute Pancreatitis

e-ISSN: 0976-822X, p-ISSN:2961-6042 Available online on http://www.ijcpr.com/ International Journal of Current Pharmaceutical Review and Research 2025; 17(9); 21-26 Bhattacharya et al. International Journal of Current Pharmaceutical Review and Research 21 Original Research Article Role of USG and Contrast Enhanced Computed Tomography in Diagnosis of the Local Complications of Acute Pancreatitis Srijak Bhattacharya1, Suparna Sahu2, Malay Karmakar3 1Senior Resident, MD, Radio Diagnosis, Department of Radio-Diagnosis, Nil Ratan Sarkar Medical College and Hospital, Kolkata, West Bengal 700014 2Senior Resident, MD, Radio Diagnosis, Department of Radio-Diagnosis, Nil Ratan Sarkar Medical College and Hospital, Kolkata, West Bengal 700014 3Associate Professor, MD, Radio Diagnosis, Department of Radio-Diagnosis, Nil Ratan Sarkar Medical College and Hospital, Kolkata, West Bengal 700014 Received: 01-06-2025 / Revised: 16-07-2025 / Accepted: 27-08-2025 Corresponding Author: Dr. Suparna Sahu Conflict of interest: Nil Abstract Introduction: Acute pancreatitis (AP) is a common gastrointestinal emergency, often complicated by local manifestations such as pancreatic necrosis, pseudocysts, fluid collections, and abscesses. Timely and accurate detection of these complications is crucial for patient management and prognosis. Imaging modalities such as ultrasonography (USG) and contrast-enhanced computed tomography (CECT) play a pivotal role in diagnosis. Aims: To evaluate and compare the effectiveness of USG and CECT in identifying the local complications of acute pancreatitis. Materials and Methods: The present study is a cross-sectional study conducted at the Department of Radiodiagnosis, Nil Ratan Sircar Medical College, Kolkata, from January 2020 to June 2021. It included a total of 50 middle-aged patients with clinically suspected or biochemically/radiologically confirmed acute pancreatitis, who were referred for abdominal ultrasonography (USG) and contrast-enhanced computed tomography (CECT) from the emergency or outpatient departments. USG and CECT were performed on all patients, and the findings were recorded in a pre-designed proforma and subsequently analyzed using appropriate statistical methods. Results: In our study of 50 acute pancreatitis patients, USG showed pancreatic enlargement (head 30%, body 30%, tail 24%), heterogeneous echo texture (72%), peripancreatic collections (54%), pseudo cysts (26%), walled-off necrosis (8%), and portal vein thrombus (6%). CECT detected peripancreatic fat stranding (88%), pancreatic enlargement (head 46%, body 58%, tail 48%), fluid collections, pseudo cysts (28–30%), walled-off necrosis (6–12%), and venous thrombosis (portal 12%, splenic 4%). Overall, CT was superior in detecting pancreatic enlargement, localizing pseudo cysts, necrosisand identifying venous thrombosis or other vascular complication. Conclusion: While USG remains a useful initial, non-invasive, bedside tool for screening local complications of acute pancreatitis, CECT is the imaging modality of choice for comprehensive evaluation, accurate diagnosis, and guiding therapeutic decisions. Integration of both modalities enhances diagnostic confidence and optimizes patient care. Keywords: Acute pancreatitis, Ultrasonography, Contrast-enhanced computed tomography, pancreatic necrosis, Pseudocyst, Peripancreatic fluid collections. This is an Open Access article that uses a funding model which does not charge readers or their institutions for access and distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0) and the Budapest Open Access Initiative (http://www.budapestopenaccessinitiative.org/read), which permit unrestricted use, distribution, and reproduction in any medium, provided original work is properly credited. Introduction Acute pancreatitis (AP) is a common and potentially life-threatening condition characterized by inflammation of the pancreas, often leading to local complications such as pancreatic necrosis, pseudocysts, abscesses, and peripancreatic fluid collections [1,2]. Timely and accurate diagnosis of these complications is crucial for effective management and improved patient outcomes [3]. Imaging modalities play a pivotal role in the assessment of AP and its complications [4]. Ultrasonography (USG) is a widely available, noninvasive imaging technique that serves as an initial diagnostic tool for detecting gallstones and assessing pancreatic morphology [5,6]. However, its utility is limited by factors such as bowel gas interference, obesity, and operator dependency, which can hinder visualization of the pancreas and peripancreatic structures [7]. Contrast-enhanced computed tomography (CECT) has emerged as the gold standard for evaluating the severity and extent International Journal of Current Pharmaceutical Review and Research e-ISSN: 0976-822X, p-ISSN: 2961-6042 Bhattacharya et al. International Journal of Current Pharmaceutical Review and Research 22 of acute pancreatitis and its local complications [8,9]. CECT provides detailed anatomical information, allowing for accurate assessment of pancreatic necrosis, fluid collections, pseudo cysts, and abscesses, thereby guiding therapeutic decision-making [10]. The general objective of the study is to evaluate and compare the role of contrast-enhanced computed tomography (CECT) and ultrasonography (USG) in detecting complications of acute pancreatitis. Specifically, the study aims to assess the diagnostic accuracy, sensitivity, and specificity of USG and CECT in identifying and evaluating the local complications associated with acute pancreatitis. Materials and Methods Study Type: Cross sectional based study Study Place: Department of RadioDiagnosis, Nil rattan Sircar Medical College, Kolkata. Study Duration: 1.5 years (January 2020 to June 2021) Study Population: Patients referred for abdominal ultrasonography and contrast enhanced CT to the Department of Radiodiagnosis, Nil Ratan Sircar Medical College and hospital with clinical suspicion of acute pancreatitis, altered biochemical parameters (serum amylase and lipase) in favour of acute pancreatitis, ultrasonography suggestive of acute pancreatitis or its complications in adult patients attending emergency or getting admitted from various clinical outdoors during January 2020 to June 2021. Sample Size: 50 patients diagnosed with acute pancreatitis Inclusion Criteria • Age: 20 – 50 years • Gender: Male and Female • All the patients who are suspected of acute pancreatitis based on clinical and laboratory findings • Patients already diagnosed as having acute pancreatitis on previous radiological investigation Exclusion Criteria • Congenital pancreatic lesions • Pancreatic carcinoma and metastasis • Traumatic injury to the pancreas • Simple cyst of the pancreas • Pregnancy • Elevated serum creatinine level (>1.5mg/dl) Study Variables • USG findings • CT findings • Output Statistical Analysis: Data from the study were analyzed using SPSS software, with continuous variables (e.g., age, liver enzyme levels) expressed as mean ± SD and compared using t-tests or Mann– Whitney U tests. Categorical variables (e.g., gender, CBD stones, and complications) were presented as frequencies and percentages, and compared using Chi-square or Fisher’s exact tests. Diagnostic accuracy (sensitivity, specificity, PPV, NPV, and accuracy) was calculated for MRCP-first and EUS-first strategies, using ERCP/intraoperative findings as the reference. Kaplan-Meier analysis may be used for time-to-intervention comparisons. A p-value < 0.05 was considered significant. Result Table 1: Distribution of the USG findings USG findings Yes No N % N % Bulky Head 15 30 35 70 Body 15 30 35 70 Tail 12 24 38 76 Collection Peripancreatic 25 50 25 50 Perirenal 6 12 44 88 Thrombus Portal vein 3 6 47 94 Splenic vein 0 0 50 100 Hypoechoic 17 34 33 66 Heterogenous echo 36 72 14 28 GB/CBD Calcification 15 30 35 70 Dilated MPD 6 12 44 88 Pleural effusion 9 18 41 82 Pseudocyst 13 26 37 74 Walled - off Necrosis 4 8 46 92 International Journal of Current Pharmaceutical Review and Research e-ISSN: 0976-822X, p-ISSN: 2961-6042 Bhattacharya et al. International Journal of Current Pharmaceutical Review and Research 23 Table 2: Distribution of the CT findings CT findings Yes No N % N % Pancreatic enlargement Head 23 46 27 54 Body 29 58 21 42 Tail 24 48 26 52 Acute fluid collections Head 11 22 39 78 Body 13 26 37 74 Tail 14 28 36 72 Perirenal 14 28 36 72 Paracolic/P elvic 14 28 36 72 Pleural effusion 9 18 41 82 Pseudocyst Head 13 26 37 74 Body 15 30 35 70 Tail 15 30 35 70 Acute necrotic collections Head 3 6 47 94 Body 5 10 45 90 Tail 8 16 42 84 Perirenal 5 10 45 90 Paracolic/Pelvic 5 10 45 90 Walled - off Necrosis Head 3 6 47 94 Body 6 12 44 88 Tail 3 6 47 94 Venous thrombosis Portal vein 6 12 44 88 Splenic vein 2 4 48 96 Peripancreatic fat stranding 44 88 6 12 Pseudoaneurysm 0 0 50 100 Haemorrhage 0 0 50 100 Table 3: Comparison of the outputs between USG and CT Outputs USG CT X² value P value Enlargement Yes 28.00% 50.70% 10.795 0.001 No 72.00% 49.30% Pseudocyst Yes 26.00% 28.70% 0.183 0.668 No 74.00% 71.30% Wald off necrosis Yes 8.00% 8.00% NA NA No 92.00% 92.00% Venous Thrombosis Yes 3.00% 8.00% 4.229 0.034 No 97.00% 92.00% International Journal of Current Pharmaceutical Review and Research e-ISSN: 0976-822X, p-ISSN: 2961-6042 Bhattacharya et al. International Journal of Current Pharmaceutical Review and Research 24 Figure 1: Distribution of the USG findings Figure 2: Comparison of the outputs between USG and CT USG of Pseudocyst in the peripancreatic region Collection in both perirenal space International Journal of Current Pharmaceutical Review and Research e-ISSN: 0976-822X, p-ISSN: 2961-6042 Bhattacharya et al. International Journal of Current Pharmaceutical Review and Research 25 Pseudocyst in relation to the body of pancreas Acute Necrotic collection Splenic vein Thrombus with walled-off necrosis Portal Vein thrombus Figure 3: On USG decreased echogenicity of the pancreas was found in 17 patients (30%) with heterogenous echotexture in 36 patients (72%). Direct visualization of gall bladder or CBD calculi was noted in 15 patients (30%) while 6 patients (12%) showed a dilated MPD. Pleural effusion was noted in 9 cases (18%). Bulky head of the pancreas was seen in 15 patients (30%); Bulky body was also noted in 15 patients (30%). A bulky pancreatic tail was seen in 12 patients (24%). Peripancreatic collection was seen in 27 patients (54%) and perirenal collection in 8 patients (16%). Pseudocyst could be diagnosed on ultrasound in 13 cases (26%); Walled off necrosis could be detected in 4 cases (8%). Thrombus was detected in the portal vein on ultrasound in 3 cases (6%) but no thrombus could be detected in the splenic vein in any of the cases. On CT, Peripancreatic fat stranding was the most common finding seen in 44 patients (88%). Pancreatic head enlargement was seen in 23 patients (46%),body enlargement in 29 patients (58%) and tail enlargement in 24 patients (48%). Acute fluid collection could be seen to involve the head in 11 patients (22%), body in 13 patients (26%) and tail in 14 patients (28%). Additional perirenal and paracolic/pelvic collections were seen in 12 patients (24%) each with pleural effusion in 9 patients (18%). Well-encapsulated pseudocyst was seen in relation to the head in 13 patients (26%), the body in 15 patients (30%) and the tail in 15 patients (30%). Acute necrotic collection was seen involving the head in 3 patients (6%), body in 5 patients (10%) and tail in 8 patients (16%). Additional perirenal and paracolic/pelvic collections were seen in 4 patients each (8%). A walled off necrosis was seen involving the head in 3 patients (6%), body in 6 patients (12%) and tail in 3 patients (6%). Portal vein thrombosis could be detected in 6 patients (12%) and splenic vein thrombosis in 2 patients (4%). In our study, pancreatic enlargement was detected in 50% of the cases on CT scan as compared to 28% of cases on ultrasound. Pseudocyst could be detected in 28% of the patients on CT scan and 26% on USG. Walledoff necrosis had an equal detection rate of 8% on USG and CT. However, better localization of both pseudocyst and walled off necrosis was possible on CT. Venous thrombosis was detectable in 8% of cases on CT scan compared with 3% cases on USG. International Journal of Current Pharmaceutical Review and Research e-ISSN: 0976-822X, p-ISSN: 2961-6042 Bhattacharya et al. International Journal of Current Pharmaceutical Review and Research 26 Discussion In our study, both ultrasonography (USG) and contrast-enhanced computed tomography (CECT) were instrumental in detecting local complications of acute pancreatitis. However, CECT provided superior visualization and localization of pancreatic and peripancreatic abnormalities, consistent with findings from previous studies [11, 12, 15]. CECT’s ability to identify complications such as pancreatic necrosis, pseudocysts, and venous thrombosis aligns with its established role as the imaging modality of choice for assessing acute pancreatitis [13,14]. The Revised Atlanta Classification offers a standardized framework for categorizing acute pancreatitis and its complications, emphasizing the role of imaging in staging severity and guiding management [13,17]. Our study’s findings are consistent with this classification, highlighting the importance of accurate imaging in determining the extent of pancreatic involvement and planning appropriate interventions [16]. Furthermore, the Modified CT Severity Index (MCTSI) has been proposed as a tool to predict outcomes in acute pancreatitis by assessing the extent of pancreatic and peripancreatic involvement [14,19]. Our study supports the use of MCTSI in routine clinical practice to guide management decisions and predict patient outcomes [12, 20]. In conclusion, while USG remains a valuable tool for initial evaluation, CECT offers superior diagnostic accuracy for detecting and localizing complications of acute pancreatitis. Integrating these imaging modalities, along with standardized classification systems like the Revised Atlanta Classification and MCTSI, can enhance the management and prognostication of patients with acute pancreatitis [11–20]. Conclusion In our study, both ultrasonography and contrastenhanced CT were effective in detecting local complications of acute pancreatitis. CT provided better visualization and localization of pancreatic enlargement, pseudocysts, walled-off necrosis, and venous thrombosis compared to USG, making it a more comprehensive tool for assessing the severity and extent of pancreatic and peripancreatic involvement. References 1. Brizi MG. The role of imaging in acute pancreatitis. PMC. 2021. 2. O'Connor OJ, et al. Imaging of the complications of acute pancreatitis. 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