Lymphangioma (LA) is a benign congenital tumor of the lymphatic system that can occur anywhere in the body that contains lymphatic vessels. It is characterized by infiltrative growth, extensive invasion of tissue spaces, and even invasion of the peripheral nervous system. There are various treatment options such as surgical excision and intratumoral injection. As the neck is a gathering place of large blood vessels and nerves, the complication rate of surgery is high and even life-threatening. Therefore, effective non-surgical treatments have been explored. In the late 1980s, Ogita, a Japanese scholar, created the method of treating lymphangioleiomyomatosis with OK-432 injection, and achieved good results. In recent years, our hospital has performed intra-focal injection of sapropterin to treat lymphangioleiomyoma in children, and achieved satisfactory results. Lymphangioleioma can be divided into 3 types according to the size of the lesion: cystic, spongy and mixed. Lymphangiectasia can occur in all parts of the body containing the lymphatic system, and about 90% of cases occur within 2 years of age. Although lymphangiectasia is a benign lesion, its infiltrative nature and close relationship with surrounding tissues make complete surgical excision very difficult, and it is associated with serious postoperative complications, such as facial nerve palsy (crooked corners of the mouth), subcutaneous effusion, celiac leakage from the wound, airway obstruction, hoarseness, and choking. Even if surgically removed, it is more likely to recur after surgery. The incidence of postoperative complications is as high as 12% to 33%, and the postoperative recurrence rate is 15-53%. Surgical complications and postoperative recurrence limit the preference for surgery as a treatment option for lymphangioleiomyomatosis. In recent years, sclerotherapy has been developed as a new method for effective treatment of lymphangioleiomyomatosis, providing an alternative to surgery for lymphangioleioma patients. In clinical practice, sclerotherapy has been found to be easier to perform, less invasive, less dangerous, and more effective, and is gradually being accepted. Previously applied in the treatment of lymphangiectasia are sclerosing agents such as pindamycin, which is an antitumor drug with inhibitory DNA synthesis and strong cytotoxicity, and its main side effects are the occurrence of interstitial pneumonia and pulmonary fibrosis, and is non-dose-related. Its severe side effects are a major concern for clinical application. Although sclerosing agents represented by pindamycin are effective for the treatment of lymphangioleiomyomatosis, limitations such as side effects limit the clinical use of these sclerosing agents. Sapylin, Sapylin, generic name: streptococcal preparation, synonym: Picinabil, OK-432, is a lyophilized mixture of Streptococcus A and penicillin G. As a non-specific immune activator, it triggers sterile inflammation, activates neutrophils, natural killer cells and cytotoxic T cells, increases neutrophils and macrophages in lymphatic sacs after injection, and induces immune cells to release inflammatory mediators, including interleukin 6 (IL-6) and tumor necrosis factor (TNF), etc. On the one hand, it increases the permeability of lymphatic sacs to make lymphatic fluid flow back. On the other hand, the intense inflammatory response induces and promotes apoptosis of lymphatic endothelial cells, promotes the proliferation of fibrous tissue, causes occlusion of lymphatic vessels and blood vessels and achieves the effect of shrinking or even complete disappearance of cystic tumor, which contributes to the shrinkage of lymphatic sacs and degeneration of lymphatic tumors, and finally makes the tumors subside significantly or completely. Poldervaart MT et al. also reported that 27% of cystic lymphangiectasias shrunk by more than 90% and 33% of patients shrunk by more than 50% without any significant There were no significant adverse effects during treatment. The results were similar to those of the present case. It was also found that sapropterin had better efficacy in cases of recurrent lymphangioleiomyoma or postoperative lymphatic effusion that could not be cured by repeated aspiration, and that sclerotherapy with streptococcal preparations was more appropriate for unresectable lymphangioleiomyoma. For the type of lymphangioleioma treated by sapropterin injection, based on the experience of this paper and combined with literature reports, the author believes that the therapeutic effect on cystic lymphangioleioma is indeed achieved with excellent therapeutic effect. Therefore, this treatment method can be the first choice of treatment for cystic lymphangiectasia. For cavernous or mixed lymphangiectasia, the drug can be spread to a considerable area of the tumor by intra-tumor injection at multiple points. Again, excellent treatment results can be achieved. Intracapsular injection of sapropterin for lymphangioleioma is a safe, effective and easy-to-operate method for treating lymphangioleioma of the neck, and it is a good method worth promoting.