Q: Given a passage with a question and an answer to that question, classify if the answer actually answers the question into 'yes' or 'no'. Output 'yes' if the answer answers the question and output 'no' if the answer does not answer the question.
Question: Does hepaticoplasty prevent cholangitis after pancreaticoduodenectomy in patients with small bile ducts?
Answer: The ratio of postoperative reduction of the bile duct diameter to that before surgery was found to be the only risk factor for cholangitis after PD. Patients with a small bile duct of 15mm in diameter preoperatively might benefit from hepaticoplasty to widen the bile duct diameter and prevent cholangitis after PD.
A:
yes