The study will be a single center observational study.~General information of the patient in form of duration of symptoms and duration of diagnosis,exocrine and endocrine insufficiency. Imaging findings such as main pancreatic duct stone,size,parenchymal calcification , ductal stricture and its location, using any medications such as antioxidants and pain killers .~The pain score will be estimated by Izbicki's pain score in last 6 months. Patients will receive standard of care during study period, and they won't receive any experimental therapy.~After 6months of ESWL further general information of the patient any addictions, a formal imaging and determining main pancreatic duct stone ,size ,calcifications and strictures and also usage of any medications for decreasing pain.~Pain will be calculated by Izbick's pain score in last 6 months . Comparing pain score and information investigators will evaluate predictive factors of pain relief after ESWL by logistic regression.
Extra corporeal shock wave therapy (ESWL) is recommended for pain management in patients with stone formation in pancreatic duct. ESWL can cause complete stone fragmentation and removal in 70% patients, associated with 85 to 90% pain relief.~Investigators aim to study, predictors pain relief in patients who undergo ESWL, to find out which patients will improve and which patients won't improve in terms of pain.