Tracking ENcapsulation of Pancreatic Collections in Acute Necrotizing Pancreatitis

Consecutive patients with ANP presenting to the hospital within 2 weeks from the pain onset will be recruited. They will undergo serial non-contrast MRI starting at day 15 and every 5 days thereafter, till complete encapsulation of PFC. Ultrasound evaluation of the collection will be performed on the day of MRI by a radiologist not involved in evaluation of MRI. The site and volume of collection as well as thickness and completeness of the capsule and solid content within the collection will be recorded independently by two radiologists. The timing of clinically significant (>50% of PFC show capsule) and complete encapsulation will be recorded. The proportion of collections encapsulating in each week after 2nd week of illness will be recorded. The association between timing of encapsulation and clinical/biochemical parameters will be assessed. The correlation between the degree of encapsulation and percentage of solid components will also be documented. Multivariate analysis will be performed to identify factors associated with timing of encapsulation.

• MRI (Diagnostic test): Serial MRI scans will be performed starting at day 15 from date of pain. Subsequent scans will be performed at 5 days interval till the clinically significant encapsulation (for all the collections in an individual patient) is seen.

Primary outcomes

• Timing of Encapsulation [1-2 months after initial MRI]: MRI scans will be performed

Sex: All, ages: 18 Years to 70 Years

Inclusion Criteria:

1. Acute necrotizing pancreatitis
2. Presentation to hospital within 2 weeks of pain onset

2\. Willing to give informed consent

Exclusion Criteria:

1. Contraindications to non- enhanced MRI (Claustrophobia, cardiac pacemaker, cochlear implant).
2. Acute on chronic pancreatitis
3. Mechanical ventilation, ionotropic support (precluding safe environment in MRI).
4. Drainage or aspiration of a collection prior to recruitment

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• Pankaj Gupta, Principal investigator, PGIMER, CHANDIGARH