CPT® Code 64746

Transection or avulsion of the phrenic nerve is a surgical procedure that involves the severing and/or removal of a portion of the phrenic nerve, which is primarily responsible for controlling the diaphragm and facilitating breathing. This procedure is typically performed to alleviate chronic pain that may be associated with various conditions affecting the diaphragm or surrounding structures. The phrenic nerve originates mainly from the fourth cervical nerve (C4) and also receives contributions from the third (C3) and fifth (C5) cervical nerves. It is important to note that the right and left phrenic nerves have distinct anatomical pathways. The right phrenic nerve is located deep to the scalene muscles in the neck and travels beneath the clavicle, passing through the root of the right lung and reaching the diaphragm at the caval opening, which is situated at the level of the eighth thoracic vertebra. In contrast, the left phrenic nerve follows a similar trajectory along the scalene muscle, entering the thoracic cavity and descending over the left ventricle before reaching the diaphragm. The surgical technique for transection involves grasping the nerve and dividing it, which may be followed by avulsion, where the nerve is twisted over a hemostat to remove it. Alternatively, the procedure may involve stretching, ligating, and dividing the nerve first distally and then proximally, allowing the proximal end of the nerve to retract into deeper tissues. This detailed understanding of the phrenic nerve's anatomy and the surgical approach is crucial for medical coders and billers to ensure accurate coding and billing for this complex procedure.