CPT® Code 38555

The procedure described by CPT® Code 38555 involves the excision of a cystic hygroma located in the axillary or cervical region, accompanied by deep neurovascular dissection. A cystic hygroma, also known as a cystic lymphangioma, is characterized by the presence of one or more cysts filled with lymphatic fluid, which results from a blockage in the lymphatic system. These cysts can be congenital, meaning they are present at birth, or they may develop later in life. The excision process begins with an incision through the skin and subcutaneous tissue that covers the cystic hygroma. In cases where the cyst is situated in the axilla, the surgeon must carefully open deeper tissues to expose the cystic mass, ensuring that surrounding nerves and blood vessels are preserved during dissection. If the cystic hygroma is located in the neck, the procedure involves incising the platysma muscle and creating subplatysmal flaps. The depth of the cystic mass may necessitate further dissection of deeper tissues, which requires meticulous care to avoid damaging critical structures such as the carotid sheath, which houses the carotid artery, internal jugular vein, and vagus nerve. The dissection continues until the cystic sac is completely separated from the surrounding tissues, allowing for its removal. In instances where multiple cystic sacs are present, each sac is dissected and excised individually. This procedure is distinct from CPT® Code 38550, which is used for the excision of a cystic hygroma that does not require deep neurovascular dissection.