“ TO DETECT THE ANATOMICAL VARIANTS AND ANOMALIES OF PANCREATIC DUCT IN MAGNETIC RESONANCE CHOLANGIOPANCREATOGRAPHY ”

ABSTRACT ID: 1020

Abstract Id: IRIA -

INTRODUCTION:Magnetic resonance cholangiopancreatography (MRCP) is a relatively new technique that does not require contrast agents or biliary and pancreatic intervention. It has proved to be an extremely useful technique to noninvasively image the biliary passage and pancreatic ductal system. MRCP is performed with moderately and heavily T2-weighted sequences and it readily depicts the relatively static fluid present within the pancreatic and biliary ductal system. Current practice utilizes MRCP to provide a detailed map of anatomic variations in preoperative patients at increased risk of bile duct and pancreatic duct injury including patients with obesity, acute cholecystitis, prior abdominal surgery, patients scheduled to undergo complicated biliary reconstruction or ERCP [2,3]. MRCP is highly accurate for diagnosing anatomic variants of both the intrahepatic and extrahepatic bile ducts, cystic duct and pancreatic duct. This technique is a useful alternative to more invasive procedures like endoscopic retrograde cholangiopancreatography (ERCP), which should be used only in cases any intervention is needed. MRCP frequently demonstrates the anatomy of the biliary passage and pancreatic duct to a better advantage than ERCP as overlapping structures can be avoided by viewing the biliary passage in different projections and planes.

The aim of the study is to demonstrate the anatomical variants and anomalies in pancreatic duct using magnetic resonance cholangiopancreatography. To evaluate the prevalence of various anomalies in pancreatic duct. To assess the association of pancreatic duct anomalies with various pancreatico-biliary pathology.

AIMS & OBJECTIVES

.

INCLUSION CRITERIA

Patients referred for MRCP to the Department of Radiology for evaluation of biliary tract-pancreatic duct pathology.

EXCLUSION CRITERIA

Images which are obscured by gross pathology involving the pancreas. Poorly acquired images due to inadequate patient breath holding and motion artefacts.

MATERIALS & METHODS :N = 230(M-

114, F-116) An observational clinical evaluation study was

conducted for 255 patients who were referred for MRCP.

MRI(Philips1.5Tesla magnet)with thin section T1 and T2axial and T2coronal,SSHMRCP 3DHR and SSHMRCP/ rad were acquired.A senior consultant radiologist assessed the pancreatic duct for congenital or anatomical variations.

Image analysis: A senior consultant radiologist blindly assessed SSh MRCP rad images and MIP images of MRCP HR SENSE sequence for presence of any common and uncommon variants.

MRCP sequences:

Thick Slab sequence- Single Shot MRCP Radial sequence (SSh MRCP Rad: TR- 8000ms; TE- 800ms; flip angle 90 degrees; FOV 300mm; 40-mm thick oblique coronal slices at 0.4mm interval on breath hold) was taken with the sections passing through the porta-hepatis and rotating around a point anterior to the portal vein. The first coronal oblique image was through the tail of the pancreas and the second image was a straight coronal image with subsequent sections obtained 15° apart from previous sections. Thin Slab sequence - MRCP High Resolution Sensitivity Encoding sequence (MRCP HR SENSE: TR- 1204ms; TE- 650ms; flip angle - 90 degrees; FOV 260; 1mm thick straight coronal sections at 0.8mm interval) Maximum intensity projection (MIP) sets of MRCP HR SENSE sequence were obtained in coronal plane.

COMMON VARIATIONS EVALUATED:

VARIATIONS INVOLVING COURSE OF PANCREATIC DUCT:

VARIATIONS INVOLVING

OTHER VARIATIONS :

:

Anomalous pancreatico bilary junction with choledochal cyst.

RESULTS:

RESULTS):

CONCLUSION:Anatomical variations of pancreatic ductal system have been encountered in various levels with existence of multiple common and uncommon anomalies. MRCP is used as the modality for safer and non-invasive evaluation of pancreatico biliary diseases and in preoperative imaging of complex surgical procedures and biliary interventions. Knowledge of these variations is useful to prevent iatrogenic injuries which increase post-operative morbidity and mortality. In our study, the types of pancreatic duct variants encountered were sigmoid (62.2%), descending (14.3%), loop (6.5%), vertical (6.1%),z-type (4.8%) and persistent duct of Santorini (0.4%). No significant association between the type of ductal system and pancreatic pathology was seen. Pancreatic Divisum, Ansa pancreatica and Annular pancreas were associated with benign pathology. No malignant pathology were reported. Three out of nine cases of long common channel were associated with choledochal cysts. No cases of biliary tract or pancreatic malignancy associated with anomalous pancreatico biliary junction were reported in our study.

The present MRCP has a limited role in physiological non distended ducts. In future studies this drawbacks can be overcome by the high resolution 3T MRI with use of hepato biliary contrast agent.

Various pancreatic ductal types and anomalies can be picked up by MRCP which is safer and non invasive when compared with ERCP. Knowledge of these variationswould help in planning surgical procedures as well as preventing unwanted interventions.

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