Giant Cystic Hygroma with Complete Encasement of the Great Vessels of the Neck in an 18 Month Old Infant

Background: Cystic hygroma is a benign condition of the lymphatic vessels. It is seen in 1 in 5000 live births. Generally lymphatic malformations are classified into microcystic and macrocystic. They commonly occur in the cervicofacial and axillary regions. The Case: A 1 year and 6 month old female child presenting with progressive right side neck swellings with later development of voice change and air hunger which is positional. Contrast enhanced CT of the neck demonstrated cystic mass with encasement of the common carotid artery and jugular vein with the mass also extending to the submandibular gland and the base of skull. After a 48 hour course of dexamethasone the patient was operated on with complete excision of the mass. Intraoperatively we also encountered right hypoglossal nerve passing through the mid part of the mass. Patient developed post-operative facial palsy with progressive improvement. Conclusion: Giant lymphatic malformations particularly in the neck region can involve great vessels and major nerves so extreme care is needed during operative interventions to avoid major operative injuries.