Ultrasound guidance is an option for the treatment of cysts with polycinnamanol sclerotherapy. Ultrasound-guided monitoring under the completion of polycinnamate sclerotherapy cyst puncture, fluid extraction, injection, etc., not only reduces the pain and risk of surgery, and cysts are not easy to recur. If the efficacy of simple cyst puncture and fluid extraction is not certain, the injection of sclerosing agent into the cyst cavity after fluid extraction is effective. Polycinnamyl alcohol has local anesthesia, analgesic effect, no obvious local pain discomfort, well tolerated. As a stimulant that can cause tissue damage and swelling, it can effectively occlude and harden the cyst cavity through inflammation and mechanization to destroy the epithelial cells of the cyst wall that have the function of secretion, leading to the disappearance of the cyst. It is effective when the cyst disappears without recurrence and the diameter of the cyst is reduced by 1/2 compared with that before the treatment, and ineffective when the diameter of the cyst is reduced by less than 1/2 compared with that before the treatment, and the size of the cyst does not change.