European Journal of Cardiovascular Medicine

Chronic pancreatitis is a long-standing inflammation of the pancreas that leads to permanent damage and impairment of its exocrine and endocrine functions. This condition can cause recurrent episodes of abdominal pain, malabsorption, and diabetes mellitus, significantly impacting the patient's quality of life. Accurate diagnosis and timely management are essential to alleviate symptoms and prevent complications.^1,2

Traditionally, the diagnosis of chronic pancreatitis has relied on clinical symptoms, laboratory tests, and imaging studies. However, clinical presentation alone can be nonspecific and overlap with other gastrointestinal disorders. Biochemical tests, including serum amylase and lipase levels, are often unremarkable in chronic pancreatitis, especially in advanced stages when the pancreas is severely damaged.^3,4

Radiological imaging plays a pivotal role in diagnosing chronic pancreatitis. Conventional radiographic methods, such as plain abdominal X-rays, can detect pancreatic calcifications but are limited in sensitivity and specificity. This has led to the widespread use of cross-sectional imaging modalities such as ultrasonography (US) and computed tomography (CT) to improve diagnostic accuracy.^5,6

Ultrasonography is a non-invasive, cost-effective, and readily available imaging technique that provides real-time visualization of the pancreas. It is particularly useful in detecting pancreatic ductal changes, calcifications, and atrophy associated with chronic pancreatitis. However, ultrasonography has limitations, including difficulty in visualizing the pancreas in obese patients or those with significant bowel gas, which can obscure the pancreatic tissue and hinder accurate assessment.^7,8

Computed tomography, on the other hand, offers detailed cross-sectional images of the pancreas and surrounding structures. It is highly sensitive in detecting pancreatic calcifications, ductal dilatation, and parenchymal changes such as atrophy and fibrosis. CT is particularly valuable in identifying complications of chronic pancreatitis, including pseudocysts, vascular involvement, and pancreatic cancer. Despite its advantages, CT is more expensive and involves exposure to ionizing radiation, which limits its use for routine follow-up.^9,10

This study aims to evaluate and compare the effectiveness of ultrasonography and CT in diagnosing chronic pancreatitis. By analyzing the strengths and limitations of each modality, we seek to determine their respective roles in clinical practice and provide recommendations for their optimal use in managing patients with suspected chronic pancreatitis

Study Design

This observational study was conducted over a period of 18 months, from December 2016 to May 2018, in the Department of Radiodiagnosis at a tertiary care hospital. The study aimed to evaluate and compare the effectiveness of ultrasonography (US) and computed tomography (CT) in diagnosing chronic pancreatitis.

Study Population

The study included patients who presented with clinical symptoms suggestive of chronic pancreatitis, such as recurrent abdominal pain, malabsorption, or diabetes mellitus, and those with elevated pancreatic enzymes. A total of 10 patients diagnosed with chronic pancreatitis were included in the study.

Inclusion Criteria

• Patients presenting with clinical symptoms indicative of chronic pancreatitis.
• Patients with elevated pancreatic enzyme levels (serum amylase and lipase).
• Patients who consented to undergo both ultrasonography and CT imaging.

Exclusion Criteria

• Pregnant patients.
• Patients who refused to undergo the imaging procedures.
• Patients with known contraindications to CT contrast media.

Study Tools and Equipment

• Ultrasonography Machine: Samsung HS 40 with a curvilinear probe (2-5 MHz frequency).
• CT Scanner: Philips MX 16-slice CT scanner.
• Contrast Media: Iopamidol for intravenous and oral contrast.

Methodology 

Patient Preparation and Consent

Informed consent was obtained from all participants after explaining the procedures, potential risks, and benefits. A detailed medical history, including any co-morbid conditions and associated habits, was recorded.

Ultrasonography

The initial evaluation was performed using a Samsung HS 40 ultrasonography machine with a curvilinear probe (2-5 MHz frequency). The pancreas was assessed for size, echogenicity, duct dilatation, calcifications, and parenchymal changes. Special attention was given to identifying atrophy and fibrosis, which are common in chronic pancreatitis. The presence of overlying bowel gas and its impact on pancreatic visualization was also noted.

Computed Tomography

CT scans were conducted using a Philips MX 16-slice CT scanner. Patients were required to fast for 6 hours before the procedure. Serum urea and creatinine levels were checked to ensure the safe administration of contrast media. For oral contrast, 20 ml of iopamidol was diluted in 1 liter of plain water and ingested one hour before the scan. Intravenous contrast was administered at a ratio of 1 ml/kg of body weight. Immediate and delayed scans were performed with 8 mm sections through the abdomen and 2 mm sections through the pancreas as needed.

Data Collection

The observations from ultrasonography and CT were independently reviewed and confirmed by experienced radiologists. Data on pancreatic visualization, size, ductal changes, calcifications, focal lesions, and extra pancreatic findings were recorded.

Statistical Analysis

Data were transferred to SPSS 22.0 for Windows software for analysis. Descriptive statistics were used to summarize the findings. Sensitivity, specificity, and positive predictive values of both imaging modalities were calculated. Comparisons were made to determine the effectiveness of ultrasonography and CT in diagnosing chronic pancreatitis and identifying complications.

Risk Management

There were no significant risks involved in this study. Ultrasonography is a non-invasive procedure, and CT scans, although involving ionizing radiation, were performed with standard safety protocols. Patients with contraindications to contrast media were excluded from the CT imaging part of the study.

The study included 10 patients diagnosed with chronic pancreatitis. The demographic analysis showed that the mean age of the patients was 29 years, with the age range spanning from 16 to 62 years. This indicates that chronic pancreatitis can affect a wide age group, although the majority of cases were found in younger adults. There was a male predominance in the study, with 7 males (70%) and 3 females (30%), reflecting the general epidemiological trend of a higher incidence of pancreatitis in males.

The age and sex distribution of the patients is detailed in Table 1. The largest groups were those aged below 20 years and those aged 21-30 years, each constituting 30% of the study population. Only one patient was identified in each of the age groups 31-40 years and above 60 years, indicating less frequent occurrence in these age brackets. The gender distribution shows a male predominance across most age groups, highlighting the higher susceptibility of males to chronic pancreatitis.

Table 1: Age and Sex Distribution of Chronic Pancreatitis Patients

The etiological analysis (Table 2) revealed that idiopathic causes were the most common, accounting for 50% of the cases. Alcoholism was the second most common cause, identified in 30% of the patients. Other etiologies included autoimmune pancreatitis and hyperlipidemia, each contributing to 10% of the cases. This distribution emphasizes the significant role of unknown and lifestyle-related factors in the development of chronic pancreatitis.

Table 2: Etiology of Chronic Pancreatitis

Ultrasonography findings (Table 3) provided crucial insights into the pancreatic alterations associated with chronic pancreatitis. The pancreas was visualized in all 10 cases, demonstrating the utility of ultrasonography in initial evaluations. A contracted pancreas was observed in 60% of the patients, while 40% had a pancreas of normal size. Echogenicity variations were also notable, with 40% of the patients showing a hyperechoic pancreas and 30% displaying a heterogeneous texture. Duct dilatation was the most prevalent finding, seen in 90% of the patients, underscoring its significance in chronic pancreatitis. Calcifications were present in 80% of the cases, highlighting chronic inflammatory changes. Pseudocysts and ascites were less common, each observed in 10% of the patients.

Table 3: Findings on Ultrasonography in Chronic Pancreatitis

CT imaging provided comprehensive visualization and detailed insights into the pancreatic and extra pancreatic changes (Table 4). Similar to ultrasonography, CT identified a contracted pancreas in 60% of the patients and a normal-sized pancreas in 40%. The echogenicity findings were consistent with those of ultrasonography, with hyperechoic pancreas and heterogeneous texture observed in 40% and 30% of the cases, respectively. CT was superior in detecting calcifications, identifying them in 90% of the patients. Additionally, CT confirmed the presence of duct dilatation in 90% of the cases and detailed the extent of pancreatic atrophy, which was noted in 60% of the patients. Pseudocysts and ascites were confirmed in the same proportions as identified by ultrasonography.

Table 4: Findings on CT in Chronic Pancreatitis

A comparison of the findings from ultrasonography and CT (Table 5) highlights the strengths and limitations of each modality. Both imaging techniques successfully visualized the pancreas in all patients. The findings of a contracted pancreas, normal size, and echogenicity variations were consistent between the two modalities. However, CT demonstrated a higher sensitivity in detecting calcifications, identifying them in 90% of the patients compared to 80% detected by ultrasonography. This underscores CT’s superior ability to detect fine calcifications and detailed structural changes. Both modalities were equally effective in identifying duct dilatation and pseudocysts, while CT provided additional detail on pancreatic atrophy, a feature less prominently detailed by ultrasonography.

Table 5: Comparison of Ultrasonography and CT Findings

The majority of patients diagnosed with chronic pancreatitis in our study were young adults, with the mean age being 29 years and a significant portion of the patients below 30 years. This finding aligns with previous research indicating that chronic pancreatitis often begins at a younger age, particularly in cases linked to genetic or idiopathic factors.^2,3,11 The male predominance (70%) observed in our study is consistent with global trends, which attribute a higher incidence of chronic pancreatitis in males primarily to higher rates of alcohol consumption.^2,12

Idiopathic chronic pancreatitis was the most common cause in our study, accounting for 50% of the cases. This high percentage reflects the global challenge in identifying specific causes for many chronic pancreatitis cases, suggesting the need for more advanced diagnostic techniques to uncover underlying etiologies.^3,4 Alcoholism was the second most common cause, noted in 30% of the patients. This finding is in line with existing literature which highlights alcohol as a major risk factor for chronic pancreatitis due to its direct toxic effects on pancreatic tissue.^7,8 The presence of autoimmune and hyperlipidemia-related pancreatitis, though less frequent, underscores the diverse etiological landscape of the disease.^5,6,13

Ultrasonography is a valuable initial imaging modality for chronic pancreatitis, given its non-invasive nature, accessibility, and ability to provide real-time imaging. In our study, ultrasonography successfully visualized the pancreas in all patients. Key findings included duct dilatation in 90% of patients, calcifications in 80%, and a contracted pancreas in 60%. These findings are significant markers of chronic pancreatitis and correlate well with previous studies that emphasize ductal changes and calcifications as primary ultrasonographic indicators of the disease.^13,14 However, ultrasonography has limitations, especially in obese patients or those with significant bowel gas, which can obscure the pancreatic tissue and hinder accurate assessment.^15,16

CT imaging provided comprehensive and detailed visualization of the pancreas, confirming and extending the findings seen on ultrasonography. CT was particularly effective in detecting calcifications, identifying them in 90% of patients, which is slightly higher than the detection rate by ultrasonography. This underscores CT's superior ability to identify fine calcifications and detailed structural changes within the pancreas.^12,14 Additionally, CT confirmed duct dilatation in 90% of cases and detailed pancreatic atrophy in 60% of patients. The ability of CT to provide clear images of the pancreas and surrounding structures makes it invaluable in diagnosing complications such as pseudocysts and ascites, which were identified in 10% of the cases each. These results are consistent with other studies that have demonstrated the high sensitivity and specificity of CT in diagnosing chronic pancreatitis and its complications.^6,8,16

Our comparative analysis of ultrasonography and CT highlights the strengths and limitations of each modality. Ultrasonography, with its non-invasive nature and cost-effectiveness, is highly suitable for initial evaluations and can effectively identify major features of chronic pancreatitis such as duct dilatation and calcifications. However, its accuracy can be compromised by patient-related factors such as obesity and bowel gas.^8,10,11 In contrast, CT provides more detailed and comprehensive imaging, particularly in detecting calcifications and structural changes like pancreatic atrophy. The higher sensitivity of CT in identifying fine calcifications and detailed pancreatic morphology underscores its role as a confirmatory tool following initial ultrasonographic assessment.^11,16 The complementary use of both modalities enhances diagnostic accuracy and provides a thorough understanding of the extent of pancreatic damage, which is crucial for effective management strategies.^12,14

Clinical Implications

The findings of this study underscore the importance of a dual-modality approach in diagnosing chronic pancreatitis. While ultrasonography should be employed as the initial diagnostic tool due to its non-invasive nature and accessibility, CT should be used to confirm the diagnosis and provide detailed assessment of the pancreatic structure and potential complications. This approach ensures comprehensive evaluation, guiding clinicians in formulating effective management plans. The high prevalence of idiopathic cases highlights the need for further research into the underlying causes of chronic pancreatitis, which could lead to more targeted diagnostic and therapeutic strategies.

In conclusion, both ultrasonography and CT are essential in diagnosing chronic pancreatitis, each offering unique advantages. Ultrasonography is valuable for initial assessments, while CT provides detailed and comprehensive evaluation, particularly in detecting calcifications and structural changes. The complementary use of these imaging modalities enhances diagnostic accuracy and aids in effective management of chronic pancreatitis. Continued research and advancements in imaging techniques are necessary to improve diagnostic capabilities and understand the diverse etiological factors contributing to chronic pancreatitis.

In conclusion, both ultrasonography and CT are essential in diagnosing chronic pancreatitis, each offering unique advantages. Ultrasonography is valuable for initial assessments, while CT provides detailed and comprehensive evaluation, particularly in detecting calcifications and structural changes. The complementary use of these imaging modalities enhances diagnostic accuracy and aids in effective management of chronic pancreatitis. Continued research and advancements in imaging techniques are necessary to improve diagnostic capabilities and understand the diverse etiological factors contributing to chronic pancreatitis.

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