Preoperative EUS Elastography for Pancreatic Texture and POPF Prediction After PD

Inclusion Criteria: * Adult patients aged 18 years or older. * Patients scheduled for elective pancreaticoduodenectomy (PD) due to pancreatic head or periampullary disease, including but not limited to: * Pancreatic cancer (all stages eligible if resectable) * Periampullary cancer * Bile duct cancer * Duodenal cancer * Patients deemed suitable for PD by the multidisciplinary pancreatic surgery team based on preoperative imaging and clinical evaluation. * Adequate organ function and physiological reserve to undergo major abdominal surgery, as determined by clinical assessment and anesthesiology evaluation. * Ability to provide written informed consent and comply with study procedures. Exclusion Criteria: * Evidence of distant metastases or locally advanced unresectable disease on preoperative imaging or clinical evaluation (e.g., liver metastases, peritoneal carcinomatosis, involvement of major vessels beyond resectability). * Previous pancreatic surgery or total pancreatectomy. * Chronic pancreatitis confirmed by clinical, radiological, or histological criteria that could confound pancreatic stiffness assessment. * Severe comorbidities or American Society of Anesthesiologists (ASA) physical status classification IV or higher, making the patient unfit for surgery. * Preoperative serum albumin less than 2.5 g/dL, indicating severe malnutrition. * Patients undergoing neoadjuvant chemotherapy or radiotherapy prior to surgery. * Pregnancy or lactation. * Contraindications to EUS (e.g., esophageal obstruction)