{'fraction_non_alphanumeric': 0.025768911055694097, 'fraction_numerical': 0.0, 'mean_word_length': 5.543478260869565, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Pancreaticoduodenectomy and its variants.

Pancreaticoduodenectomy (PD) is a complex surgical procedure involving resection of the duodenum, the pancreatic head and uncinate process, and the distal common bile duct. It is most commonly performed for periampullary malignancy but may also be indicated in select cases of chronic pancreatitis or benign periampullary tumors. When evaluating a patient for potential PD, the foremost question is determining the ability to perform an adequate (margin-negative) and safe resection. Herein, we present the surgical technique for performing a pylorus-preserving PD divided into the extirpative and reconstructive phases. There are a number of accepted alternatives to the pylorus-preserving PD as presented, and the commonly accepted alternatives will also be reviewed. The sequence of steps in the extirpative phase may vary depending on the tumor location (i.e., head, neck, and uncinate) and extent of disease, whereas reconstruction techniques may vary based on a given surgeon's training and preference. Multiple advancements in recent years, including those presented below, have helped to significantly reduce the operative mortality associated with PD.