Elastography in the Diagnosis of Chronic Pancreatitis
Elastography in the Diagnosis of Chronic Pancreatitis
Chronic pancreatitis is a progressive inflammatory condition where progressive fibrosis and
 calcification results in loss of physiological pancreatic function (both endocrine and
 exocrine). The structural, fibrotic changes of chronic pancreatitis can only be seen in
 advanced disease with conventional radiology tests and the diagnosis of chronic pancreatitis
 early in the disease course remains challenging. Early diagnosis and treatment of chronic
 pancreatitis can prevent the complications of pain and malnutrition and improve the quality
 of life of patients. Endoscopic ultrasound (EUS) has recently become a favoured method for
 diagnosing early structural fibrotic changes of chronic pancreatitis in clinical practice;
 however this technique is subjective with sub-optimal intra-observer agreement. A new
 technique called elastography, performed during EUS, quantitatively measures tissue stiffness
 which may give more reliable results. This study aims to assess whether EUS elastography can
 accurately identify for chronic pancreatitis.

 Patients referred for EUS examinations will be identified and recruited prospectively. The
 investigators will perform endoscopic ultrasound examinations with elastography readings in
 two groups of patients: those referred for EUS with suspicion of chronic pancreatitis and
 those referred for EUS for assessment of abdominal pain without risk factors or any other
 tests suggesting chronic pancreatitis. The elastography readings will then be compared to the
 gold standard which is a composite evaluation including standard EUS examination using
 morphological appearance (Rosemont classification), and other tests already performed
 including cross-sectional imaging (MRCP and CT), patient history and faecal pancreatic
 elastase (FEL-1).

 Patients will be identified and data collected prospectively. There is no randomization or
 blinding involved in the study as the endoscopists will need to be aware of the indication
 for referral in order to carry out a complete examination.
Chronic pancreatitis is a chronic inflammatory condition where progressive fibrosis and
 scarring leads to loss of pancreatic exocrine and endocrine function and can lead to
 development of malnutrition, weight loss, abdominal pain and impaired quality of life.
 Patients with chronic pancreatitis have a high risk of pancreatic adenocarcinoma compared to
 the general population so it is vital that they are identified early in the disease. There
 are numerous causes of chronic pancreatitis therefore early detection and treatment can
 prevent irreversible changes and symptoms developing.

 Trans-abdominal ultrasound (US), computed tomography (CT) and magnetic resonance imaging
 (MRI) are currently used to investigate patients with symptoms suggestive of chronic
 pancreatitis. These tests may, however, fail to show early changes in the bile ducts or small
 areas of inflammation in pancreatic tissue. In areas of diagnostic uncertainty, endoscopic
 ultrasound (EUS) is currently used to provide a more detailed assessment.

 EUS uses a flexible endoscope (similar to a gastroscope) passed into the stomach via the
 mouth. The EUS scope has the addition of a tiny ultrasound probe on the tip which is used to
 acquire high resolution detailed images of the pancreas and other extra luminal structures
 (lymph nodes, bile ducts, mediastinum) lying only centimeters from the tip of the probe.
 Despite the advantages of EUS, image interpretation can be extremely challenging and in the
 presence of inflammation. Morphological changes of chronic pancreatitis seen at EUS have been
 classified according to the Rosemont classification; however, the findings are subjective
 with sub-optimal intra-observer agreement.

 Elastography is an ultrasound technique used to assess stiffness of tissues in the body. It
 has established applications in detecting chronic liver disease, and improving diagnostic
 accuracy in breast and prostate cancers. Pancreatic elastography is now able to be performed
 during a standard EUS examination using the existing equipment (in a similar manner to
 Doppler). Tissue elasticity is measured and represented with different colours (on a scale of
 1 to 255). The colour signal (red-green-blue) is then superimposed on the conventional
 grey-scale image. Areas of increased stiffness are marked with dark blue, intermediate areas
 with green and soft tissue areas with red. Areas of interest are able to be marked to give an
 elasticity reading and this is also compared to a control area of stomach wall to calculate a
 ratio (strain ratio).

 Elastography has now become part of the routine EUS exam following several studies that have
 shown elastography can be successfully used to identify malignant pancreatic and lymph node
 masses with high sensitivity allowing accurate targeting of fine needle aspiration (FNA)
 biopsies and early confirmation or exclusion of cancer.

 The investigators hypothesise that changes of chronic pancreatitis can also be detected using
 elastography assisted EUS. Detecting change at an early stage will benefit patients and
 potentially reduce complications that result from chronic pancreatitis such as malnutrition,
 pain and osteoporosis.
Inclusion Criteria:

 -  Age 18 or over,

 -  Patients referred for EUS for investigation of abdominal pain without a cause found on
 assessment with MRI and FEL-1.

 -  Patients referred for EUS for chronic pancreatitis assessment based on MRI and/or
 FEL-1 testing.

 Exclusion Criteria:

 -  Patients with known solid pancreatic lesions

 -  Patients under the age of 18

 -  Patients who decline EUS examination

 -  Patients referred for EUS with indications other than epigastric pain or suspicion of
 chronic pancreatitis