Comparison of contrast-enhanced CT with diffusion -weighted MRI in the Evaluation of patients with acute biliary pancreatitis

Diffusion-weighted Imaging: New Paradigm in Diagnosis of Early Acute Pancreatitis

BACKGROUND

Diffusion-weighted imaging (DWI) has come up as a newer diagnostic modality for the diagnosis of early functional changes in various organs including the pancreas. DWI has shown the ability of early and accurate diagnosis of inflammatory pathologies, before the appearance of morphological changes on imaging.

OBJECTIVES

The objectives of this study were to study the diagnostic accuracy of DWI in the diagnosis of early acute interstitial pancreatitis.

MATERIALS AND METHODS

The present retrospective observational study was conducted at the department of radiodiagnosis of a tertiary teaching hospital for 1 year. Fifty patients who underwent magnetic resonance imaging of the pancreas with clinical or laboratory diagnosis of early pancreatitis were included in the study. The diagnostic accuracy of DWI was analyzed on the basis of quantitative (apparent diffusion coefficient [ADC] values) evaluation in the diagnosis of early acute pancreatitis. Threshold values for ADC were derived for differentiation of inflamed versus normal pancreas. Sensitivity, specificity, positive predictive value (PPV), and negative predictive values (NPV) were obtained by drawing the receiver operating characteristic (ROC) curve.

RESULTS

The mean ADC values in the patient group (0.882 × 10 -3 mm 2 /s ± 0.102) were significantly lower than the control group (1.178 × 10 -3 mm 2 /s ± 0.232) with P < 0.001. The ROC curve deciphered a cutoff value of 0.937 × 10 -3 mm 2 /s with a sensitivity of 84%, specificity of 86%, PPV of 85.71%, and NPV of 84.31% for diagnosis of acute pancreatitis using quantitative ADC values.

CONCLUSION

DWI can thus be a succinct modality for early diagnosis of pancreatitis with excellent diagnostic accuracy and superlative advantage of lack of contrast and radiation in comparison to computed tomography scan.

Correlation between Balthazar CT grading, CECT necrosis volume, attenuation value, and prognosis of patients with acute necrotizing pancreatitis

To analyze the correlation between Balthazar CT grading and contrast-enhanced CT necrosis volume and attenuation value and prognosis of patients with acute necrotizing pancreatitis. Ninety-two patients with acute necrotizing pancreatitis who were treated in the hospital were selected between June 2019 and June 2021, and they were divided into the poor prognosis group and the good prognosis group according to the clinical prognosis at 6 months of follow-up. Balthazar CT, contrast-enhanced CT necrosis volume, and attenuation value were compared between the 2 groups. Multivariate logistic regression analysis was used to analyze the influencing factors. Receiver operating characteristic curve was adopted to analyze the predictive value. Among the 92 participants, there were 28 cases with good prognosis (30.43%) and 64 cases with poor prognosis (69.57%). The Acute Physiology and Chronic Health Evaluation II score, C-reactive protein, urea nitrogen, Balthazar CT, necrotic volume, and average attenuation value of the poor prognosis group were significantly higher than those of the good prognosis group (all P values <.05). The results of the multivariate logistic analysis showed that Balthazar CT grade, necrotic volume, and average attenuation value were independent risk factors for poor prognosis in patients with acute necrotizing pancreatitis (all P values <.05). The area under the curve of Balthazar CT grade, necrotic volume, average attenuation value, and the joint detection in predicting the prognosis of patients with acute necrotizing pancreatitis were 0.765, 0.624, 0.764, and 0.861, respectively. The Balthazar CT grading, necrosis volume, and average attenuation value are significantly higher among patients with acute necrotizing pancreatitis complicated with poor prognosis, and they are also independent risk factors for poor prognosis in patients with acute necrotizing pancreatitis, and can help clinically predict the prognosis of patients with acute necrotizing pancreatitis, and the combined detection has better application effects.

Emerging imaging techniques for acute pancreatitis

Acute pancreatitis (AP) is caused by acute inflammation of the pancreas and adjacent tissue and is a common source of abdominal pain. The current CT and MRI evaluation of AP is mostly based on morphologic features. Recent advances in image acquisition and analysis offer the opportunity to go beyond morphologic features. Advanced MR techniques such as diffusion-weighted imaging, as well as T1 and T2 mapping, can potentially quantify signal changes reflective of underlying tissue abnormalities. Advanced analytic techniques such as radiomics and artificial neural networks (ANNs) offer the promise of uncovering imaging biomarkers that can provide additional classification and prognostic information. The purpose of this article is to review recent advances in imaging acquisition and analytic techniques in the evaluation of AP.